72 results on '"CORRELACION GENETICA"'
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2. Assessing the phenotypic variation, heritability and genetic advance in bread wheat (Triticum aestivum L.) candidate lines grown under rainfed semi-arid region of Algeria.
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Lamara, Asma, El Abidine Fellahi, Zine, Hannachi, Abderrahmane, and Benniou, Ramdane
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WHEAT , *ARID regions , *PHENOTYPIC plasticity , *WHEAT breeding , *GENETIC variation , *GRAIN yields , *DRY farming , *HERITABILITY - Abstract
The genetic improvement of any breeding population largely depends upon the magnitude of genetic variability present. This study was carried out to estimate parameters of the genetic variation among 13 quantitative traits of bread wheat evaluated at INRAA-Setif institute (Algeria) during the 2020--2021 crop season in a rainfed environment. 34 genotypes including four control checks were planted in a randomized complete block design with three replications. Genotypes showed significant variations for almost all the studied traits. Proline content, spikes weight, and grain yield exhibited a high genotypic coefficient of variation along with moderate to high heritability coupled with a high genetic gain, suggesting the implication of additive gene action. The number of spikes, spikes weight, and thousand kernel weight were significantly and positively correlated with grain yield at both phenotypic and genotypic levels. Path analysis results showed that spikes weight is an important route through which most of the measured traits influenced indirectly grain yield. Lines L1, L20, L28, L16, and L18 exhibited a sizeable grain yield advantage, which suggests they are potential candidates for future release and could be incorporated into the wheat breeding programs as parents to improve yield in the rainfed environments of Algeria. [ABSTRACT FROM AUTHOR]
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- 2022
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3. Genetic parameters for ultrasound-evaluated carcass and body traits in Anglo-Nubian goats.
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Figueiredo-Filho, Luiz A. S., Sarmento, José L. R., Campelo, José E. G., Santos, Natanael P. S., Sena, Luciano S., and Torres, Tatiana S.
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GOAT breeds , *BODY size , *GOATS , *GENETIC correlations , *MEAT quality - Abstract
Meat goat breeding programs should prioritize the identification and selection of genetically superior animals for traits related to meat quality and carcass yield in order to increase the value of the final product. Objective: To estimate (co)variance components and genetic parameters for ultrasound-measured carcass traits, body size and body weight in Anglo- Nubian breed goats raised in the Mid-North region of Brazil. Methods: (Co)variance components and genetic parameters were estimated using the single and two-trait animal model analyses via Bayesian inference for loin eye dimensions (area, length, and depth), sternal fat thickness, rump height, chest circumference and depth, leg perimeter, and body weight. Results: Heritability estimates were higher when two-trait analyses were used. This finding implies that it is possible to recover part of the additive genetic variance included in the residual variance due to the correlation between traits. Genetic correlations between carcass and body size traits showed different magnitudes. On the other hand, genetic correlations between the traits related to muscularity showed high magnitudes. Conclusions: Body weight was not a good indicator of muscularity; therefore, it is not recommended as a criterion for indirect selection to improve carcass traits of Anglo-Nubian goats. Leg perimeter and chest circumference may be important to construct selection indexes in meat goat breeding programs. [ABSTRACT FROM AUTHOR]
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- 2021
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4. Efecto de la selección genética en contra de las emisiones de metano sobre los componentes de la leche.
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Calderón-Chagoya, Rene, Heberth Hernández-Medrano, Juan, de Jesús Ruiz-López, Felipe, García-Ruiz, Adriana, Eliezer Vega-Murillo, Vicente, Israel Mejía-Melchor, Enoc, Garnsworthy, Phil, and Iván Román-Ponce, Sergio
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MILKFAT , *MILK proteins , *GENETIC correlations , *MILK yield , *HAIR follicles - Abstract
This study aimed to estimate the response to selection through different selection indices between methane production and milk production and its components in specialized tropical, dual-purpose, and family dairy systems. Methane emissions were sampled during milking using the Guardian-NG gas monitor; milk samples were collected individually during methane sampling. DNA was extracted from the hair follicles of all the animals included in this study. The variance and covariance components were estimated using the mixed model methodology. Due to the incomplete genealogical information, molecular markers were used to build the genomic relationship matrix (Matrix G). The estimated heritability for methane emissions during milking was 0.18 and 0.32 for the univariate and bivariate analysis, respectively. The genetic correlation between the milk fat and protein percentages and methane emissions during milking was negative, -0.09 and -0.18, respectively. The response to selection, estimated through selection indices, demonstrated that it is feasible to reduce methane emissions up to 0.021 mg/L during milking in five generations without detriment to milk components. [ABSTRACT FROM AUTHOR]
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- 2021
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5. Parámetros genéticos en la varianza residual de variables de comportamiento en toros de lidia.
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Domínguez-Viveros, J.
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GENETIC correlations , *MULTIVARIATE analysis , *GENOTYPE-environment interaction , *HERITABILITY , *VARIANCES - Abstract
The objectives were to analyze the presence of genetic variance in the residual variance of behavior notes in fighting bulls. From a livestock ranch, the conditional residuals were analyzed (RCON; ê = y - [y|a] = y - Xß - Za) and marginal (RMAR; = y - [y] = y - Xß), from the notes of horse tienta (n, 2369), foot tienta (n, 1432), horse bullfight (n, 792) and foot bullfighter (n, 820); in two databases: BD1, logarithmic transformation; BD2, logarithmic transformation eliminating extreme data (x ±2s). With the MTDFREML software, a multivariate analysis (four notes) was performed within the residual type and for each database; heritability (h) and genetic correlations (rg) were calculated through variables. The h2 ranged between 0.14 and 0.96, with an average value of 0.58; h2 of RMAR in BD2 presented above estimates (> 0.78). These results show genetic variability in the residual variance and present the possibility of response to selection (environmental channeling) to reduce environmental variance. The selection for residual variance can improve the response to the concepts of resilience, plasticity, robustness and rusticity. The rg were positive, in the range of 0.01 to 0.99 and an average value of 0.79; with these rg there may be a correlated response in the residuals of the four notes. [ABSTRACT FROM AUTHOR]
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- 2020
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6. Genetic parameters and association between agronomic traits in special-grain common bean (Phaseolus vulgaris L.) genotypes.
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Giroletta dos Santos, Carla Medianeira, dos Santos Silva, Jeferson Antonio, Prevedel Capristo, Denise, Matinho Correa, Agenor, and Pereira Ribeiro, Larissa
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COMMON bean , *GENETIC correlations , *PLANT breeding , *PATH analysis (Statistics) , *GRAIN yields , *TRAIT intercorrelations , *GENOTYPES - Abstract
Estimates of genetic parameters allow to determine the genetic variability present in a population, constituting one of the initial steps in a breeding program. The objectives of this study were to estimate genetic parameters and identify agronomic traits directly and indirectly correlated with grain yield (GY), as well as to estimate their direct and indirect effects on the yield of special-grain common bean genotypes. The experiment was carried out in the 2016/2017 season, in a complete blocks design, with three repetitions. The evaluated traits were days to flowering, days to maturity, first pod height, plant height, number of pods per plant, number of grains per pod, mass of hundred grains, and grain yield. Data were subjected to analysis of variance, and genetic parameters were estimated followed by phenotypic and genotypic correlations. Phenotypic and genotypic correlations were split into direct and indirect effects by path analysis. The studied population seemed promising for breeding purposes considering most traits. Correlation and path analyses indicated that there was a positive direct effect of days to maturity on grain yield. The traits days to maturity and mass of hundred grains can be used in indirect selection aiming at higher grain yield. Path analysis also revealed that the indirect effects of number of pods per plant and number of grains per pod should be taken into consideration in the genetic breeding of the common bean for the increased grain yield. [ABSTRACT FROM AUTHOR]
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- 2020
7. Valoración genética de unidades comportamentales en una ganadería de lidia colombiana.
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Calero Quintero, David, Uribe Ceballos, José Reinel, Bartolomé Rodríguez, Daniel José, Muñoz Flores, Jaime Eduardo, and González Valencia, María Fernanda
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GENETIC correlations , *RANCHES , *BREEDING , *CONSANGUINITY , *ANIMAL behavior , *STALLIONS , *HORSE breeding - Abstract
An ethogram was designed to disaggregate the behaviour of fighting cattle, quantify bravery and consolidate selection. 933 females and 787 males from the Colombian cattle ranch "Ernesto González Caicedo" (EGC), Santa Coloma lineage, at Popayán, Cauca, Colombia, were analysed. The behavioral units (UC) identified were fixity (FIJ), starting distance (DIS), readiness (PRO), reloading (RGR), absence of pain (DOL), degree of jealousy (GEN), distance (RDO), humiliating (HUM), repeat (REP), lunge type (TEM), bottom (FON), strength (FZA) and absence of defects (AUD). Information was analysed with DeLidia® software, developed for this research. The CU were adjusted according to the effect of age, consanguinity, weight, sex, place, type of celebration, number of rods, bullfighter and picador. Inheritance indices, phenotypic and genetic correlations, and breeding values of stallions were estimated. The resulting h2 values for the UC FZA and REP were 0.06 ± 0.03 and 0.36 ± 0.026, respectively, with an average of 0.21 ± 0.05 for all UC. All rg were positive except for those involved with FZA. The lowest positive value of rg was 0.1 for GEN and HUM, while the highest was 0.79 for FIJ and RDO. Trends of VG were positive and different from zero (P <0.01), except FZA (-0.004 ± 0.0004). The gain per year, as a percentage part of the mean, was -0.191% for FZA and 1.024% for REP. Resultant h2 and VG suggest their usefulness in selection programs, favouring greater genetic progress. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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8. Genetic parameters between somatic cell score and production traits for Holstein cattle in Southern Brazil.
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Romano, Gabrieli S., Pinto, Luis Fernando B., Valloto, Altair A., Horst, José-Augusto, and Pedrosa, Victor B.
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SOMATIC cells , *HOLSTEIN-Friesian cattle , *DAIRY cattle , *HEALTH of cattle , *MILK yield , *GENETIC correlations , *MILK quality - Abstract
Background: Somatic cell score is an important parameter to predict milk quality and health of cows. However, in countries like Brazil, this trait is still not selected on a large scale, and no genetic parameters are reported in the literature. Objective: To estimate the variance components and genetic parameters for somatic cell score, milk yield, fat yield, protein yield, fat percentage, and protein percentage in Holstein cows. Methods: Records from 56,718 animals were used to estimate variance components, heritability, and genetic correlations using a multi-trait animal model by the REML method. Results: The heritability estimates were 0.19 for somatic cell score, 0.22 for milk yield, 0.26 for fat yield, 0.18 for protein yield, 0.61 for fat percentage, and 0.65 for protein percentage. The estimates of genetic correlations among analyzed traits ranged from -0.50 to 0.82. Conclusion: The low heritability observed for somatic cell score indicates that selection for this trait should result in benefits related to animal health and milk quality, but only in the long term. The low correlation between productive traits and somatic cell score indicates that inclusion of somatic cell score in animal breeding programs does not interfere negatively with the genetic selection for milk yield or solids. [ABSTRACT FROM AUTHOR]
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- 2020
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9. ASOCIACIÓN GENÉTICA DEL ÍNDICE DE PRODUCTIVIDAD ANUAL CON CARACTERÍSTICAS REPRODUCTIVAS Y DE CRECIMIENTO EN BOVINOS PRODUCTORES DE CARNE.
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Ángel Hidalgo-Moreno, Jorge, Núñez-Domínguez, Rafael, Domínguez-Viveros, Joel, Ramírez-Valverde, Rodolfo, and Rodríguez-Almeida, Felipe
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GENETIC correlations , *COW-calf system , *MAXIMUM likelihood statistics , *ANIMAL models in research , *HERITABILITY , *CALVES , *BIVARIATE analysis , *CATTLE fertility - Abstract
The reproductive performance of the cow and its maternal ability affect the profitability of the cow-calf production systems. The objective of this study was to estimate components of (co) variance, heritability (h2) for the annual productivity index (PI), age at first calving (AFC), calving interval (CI) and weaning weight (WW), and genetic correlations (rg) among these traits, as well as the response to the selection in PI. The PI was calculated as the WW of the calf times 365, divided by the CI. The performance records used are from Brangus Negro (BN), Salers (SA) and Suizo Europeo (SE) cattle, coming from ranches in several Mexican states; the pedigree included 68 474 (BN), 15 594 (SA) and 187 294 (SE) animals. Univariate and bivariate analysis, which consider the animal model, were performed to estimate components of (co) variance and genetic parameters using the restricted maximum likelihood method, with the ASReml program. The direct h2 for PI varied from 0.06 to 0.12, for AFC from 0.01 to 0.15, for CI from 0.07 to 0.12 and for WW from 0.15 to 0.23. The estimators of rg ranged from -0.09 to -0.76 for PI-AFC, from -0.90 to -0.93 for PI-CI and from 0.17 to 0.97 for PI-WW. The selection for WW resulted in higher PI correlated changes (between 0.06 and 1.53 kg cow-1 year-1) than those obtained when using the direct selection for PI. The genetic correlations of PI with the other traits were favorable. The selection for WW, and then for PI, can genetically improve the annual productivity of cows. [ABSTRACT FROM AUTHOR]
- Published
- 2019
10. Single- and multiple-trait BLUP in genetic selection of parents and hybrids of grain sorghum.
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Oliveira de Souza, Nadson, Silva Alves, Rodrigo, Teodoro, Paulo Eduardo, Aparecida Silva, Lidiane, Dessaune Tardin, Flávio, Baldoni Tardin, Aisy, Vilela de Resende, Marcos Deon, and Lopes Bhering, Leonardo
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SORGHUM , *GRAIN yields , *GENOTYPES , *LIKELIHOOD ratio tests , *RESTRICTED maximum likelihood (Statistics) - Abstract
To increase yield, breeding programs must search for innovative and efficient methodologies for the development and selection of superior genotypes. Therefore, this study aimed to compare the single- and multiple-trait best linear unbiased prediction (BLUP) in genetic selection of parents and hybrids of grain sorghum. For this, an experiment conducted in alpha-lattice design with two replications was used. Flowering time (FT), plant height (PH), and grain yield (GY) were evaluated in 502 grain sorghum hybrids obtained by the cross of ten restorer lines and 54 male-sterile lines. Variance components were estimated via restricted maximum likelihood (REML). Significant effects of restorer lines, of male-sterile lines, and of specific combining ability were detected by the likelihood ratio test (LRT). The estimates of variance components, genetic parameters, and correlations were similar when obtained via single- and multiple trait-BLUP. Considering hybrids, the multiple-trait BLUP resulted in slightly higher predicted selection gain for the three evaluated traits and, therefore, can be efficiently applied in the genetic selection of grain sorghum. [ABSTRACT FROM AUTHOR]
- Published
- 2019
11. Evaluación genética para características de peso en ganado Brahman comercial.
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Bedoya O., Christian, Alzate R., Jovany, Ángel C., Juan, Escobar R., Carlos, and Calvo C., Samir
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ZEBUS , *BIRTH weight , *GENETIC correlations , *BIRTH certificates , *HERITABILITY , *CATTLE reproduction , *PREGNANCY in animals - Abstract
Objective. Evaluate genetically the traits of birth weight and weaning weight in commercial Brahman cattle. Materials and methods. A total of 1.015 records of birth weight (BWT) and weaning weight adjusted to 270 days (WW270), were evaluated. Data correspond to the offspring born between 2002 and 2014 belonging to "La Envidia" farm, located in the municipality of Planeta Rica, Córdoba. A bi-character animal model that included, additive genetic effect, maternal effect and sex, month, year and age at weaning as fixed effects, was used. Genetic parameters were estimated using the MTDF-REML software. Results. The average and coefficient of variation (CV) of BWT was 29.62±3.13 kg and 10.59%, respectively. The mean and CV for WW270 was 216.71±26.97 kg and 12.45%, respectively. The estimates of direct heritability were 0.44±0.143 and 0.39±0.12 for BWT and WW270, respectively. Maternal heritability was 0.09±0.092 and 0.42±0.087 for BWT and WW270, respectively. The estimated genetic and phenotypic correlation between the evaluated characteristics was 0.11 and 0.13, respectively; with genetic progress per year of -2.02 kg for BWT and 7.81 kg for WW270. Conclusion. The estimations of heritability indicate the existence of direct additive genetic variability, evidencing the opportunity of genetic gain through selection. However, environment have a great influence on birth weight and weaning weight traits, which is why special attention should be paid to the handling and nutrition of females during pregnancy and of calves from birth to weaning. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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12. Efectos genéticos en el crecimiento predestete de corderos Hampshire.
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Rodriguez-Almeida, F. A., Pérez-Camacho, C., Domínguez-Viveros, J., and de la Cruz-Colín, L.
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The 30-day weight (P30; 1072) and the weaning (P75; 1750) of 10 flocks were analyzed in Hampshire lambs, to develop two objectives: to evaluate the expression of the genetic effects in the pre-weaning growth, and to analyze the possible implications in the genetic progress. The analyzes were univariate (ANAU) and bivariate (ANAB), through mixed models that included the fixed effects of contemporary groups and the covariable age of the mother; and as random, the direct and maternal genetic effects, the genetic covariance between them and the maternal effects of the permanent environment. Direct herilabilily (h²) and maternal (m²), genetic correlations (rdm), and genetic values (VG) were estimated. With the rank correlations (CR) in the VG, the ranking of the population and of the sire was analyzed; in addition, the genetic trends (TG) of the VGs were analyzed. The h² was in the range of 0.14±0.03 to 0.19±0.04; the m² in ANAU was 0.08±0.04 and 0.02±0.03, with ANAB the estimate was of 0.22±0.05 and 0.13±0.03. The rdm of ANAU was +1±0.15 in P30 and -1±0.18 in PD, changing in the ANAB to -0.46±0.10 and -0.20±0.07, respectively. The behavior of the TG in the ANAU was associated to the magnitude and sign of the rdm; likewise, the rdm of the ANAU implied changes in the ranking of sires, which was reflected in the TG and the CRs. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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13. Parámetros y tendencias genéticas de variables de crecimiento para bovinos Romosinuano en México.
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Martínez Rocha, Ricardo E., Valverde, Rodolfo Ramírez, Domínguez, Rafael Núñez, and García Muñiz, José G.
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Introduction: Romosinuano cattle is a breed originated in Colombia, but in Mexico there are organized breeders since two decades ago. This breed has a small population size in Mexico and no published studies documenting basic aspects to establish a breeding program were found. The objective of this study was to estimate genetic parameters for birth weight (BW) and weaning weight adjusted to 240 d (WW), as well as to document genetic trends for both traits, in the Romosinuano cattle population of Mexico. Method: The database was provided by “Asociación Mexicana de Criadores de Ganado Romosinuano y Lechero Tropical A. C". A total of 895 and 517 records of BW and WW were used. The pedigree included 4,537 animals born between 1950 and 2016. Analyses were carried out with the ASReml program. Preliminarily, univariate models were used to identify the best one for each trait, through the likelihood ratio test. The bivariate animal model included the fixed effects of contemporary group (year-herd-season-sex), calving age as linear and quadratic covariate, and the linear covariate proportion of Romosinuano gene. The random effects were direct additive genetic and sire by contemporary group interaction for both traits, plus maternal additive genetic for WW. Genetic trends were estimated using linear regression of average breeding values on birth year of the animals. Results: Estimations of direct heritability for BW and WW were 0.19 ± 0.09 and 0.21 ± 0.12. Maternal heritability for WW was 0.04 ± 0.05. The proportion of phenotypic variance explained by the interaction of sire by contemporary group were 0.21 ± 0.05 and 0.11 ± 0.08, for BW and WW, respectively. The genetic correlation between BW and WW was strong and positive (0.69 ± 0.28). Genetic trends for BW and WW were not different from zero (P > 0.05). Conclusion: The heritability estimates for BW and WW showed enough genetic variability to implement a selection program for these traits. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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14. Study of the Host Genetic Control over the Ruminal Microbiota and their Relationships with Methane Emissions in Dairy Cattle
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Alejandro Saborío Montero
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Genetic correlation ,Holobiability ,Microbiota ,Correlación genética ,Principal component analysis ,Metano ,Microbiota relationship matrix ,Matriz de relación de la microbiota ,Microbiability ,Heritability ,Heredabilidad ,Microbiome ,Methane ,Microbioma - Abstract
[ES] El análisis del control genético del hospedador sobre su microbiota ha sido señalado recientemente como un tema prometedor en diferentes campos de estudio. La relación entre el holobionte hospedador-microbioma y los fenotipos en el ganado lechero podría conducir a nuevos conocimientos en los programas de selección genética. Dentro de esta tesis doctoral, se realizó la estimación y análisis a través de diferentes enfoques estadísticos con el objetivo de desentrañar el control genético del hospedador sobre la microbiota en ganado lechero. Además, se analizó el rasgo de concentración de metano como un fenotipo potencial para ser incluido en el programa de mejora de ganado lechero español. Mayor abundancia relativa de la mayoría de los eucariotas (principalmente protozoos ciliados y hongos) y algunas arqueas (Methanobrevibacter spp. Methanothermus spp. y Methanosphaera spp.) fueron factores de riesgo para ser clasificadas en la categoría alta. Se propuso un conjunto de modelos de ecuaciones estructurales (SEM) de tipo recursivo dentro de un marco de Cadenas de Markov Monte Carlo (MCMC) para analizar conjuntamente la relación hospedador-metagenoma-fenotipo. Se estableció un modelo bivariado no-recursivo como punto de referencia. La heredabilidad de CH4 se estimó en 0,12 ± 0,01 en ambos modelos, recursivo y no recursivo. Asimismo, las estimaciones de heredabilidad para la abundancia relativa de los taxones se superpusieron entre los modelos y variaron entre 0.08 y 0.48. Las correlaciones genéticas entre la composición microbiana y el CH4 variaron de -0,76 a 0,65 en el modelo bivariado no recursivo y de -0,68 a 0,69 en el modelo recursivo. Doce matrices de relación de microbiota (K) fueron construidas a partir de diferentes métricas de distancia del microbioma, con el objetivo de comparar su desempeño dentro de un marco de estimación de componentes de varianza para CH4 y toda la microbiota. Análisis de simulación (n = 1000) y datos reales fueron desarrollados considerando cuatro modelos posibles: un modelo genómico aditivo (GBLUP), un modelo de microbioma (MBLUP), un modelo de efectos genéticos y microbioma (HBLUP) y un modelo de efectos de interacción genético, microbioma y genético × microbioma (HiBLUP). Un nuevo término "Holobiabilidad" fue definido para referirse a la proporción de la varianza atribuible a los efectos del holobionte hospedador-microbioma. Las estimaciones a partir de datos reales usando HiBLUP variaron dependiendo de la K utilizada y estuvieron entre 0.15-0.17, 0.15-0.21 y 0.42-0.59 para heredabilidad, microbiabilidad y holobiabilidad, respectivamente. El conjunto de datos de microbioma fue agregado a través de análisis de componentes principales (PCA), en pocos componentes principales (PCs) que fueron utilizados como aproximaciones del metagenoma central. Parte de la variabilidad condensada en estos PC está controlada por el genoma de la vaca, con estimaciones de heredabilidad para el primer PC (PC1) de ~ 0,30 en todos los niveles taxonómicos, con una gran probabilidad (> 83%) de que la distribución posterior sea > 0,20 y con un intervalo de mayor densidad posterior al 95% (95% HPD) no conteniendo cero. La mayoría de las estimaciones de correlación genética entre PC1 y metano fueron grandes (>0,70) en todos los niveles taxonómicos, con la mayor parte de la distribución posterior (> 82%) siendo > 0,50 y con su 95% HPD no conteniendo cero. Estos resultados sugieren que todo el metagenoma del rumen regula recursivamente las emisiones de metano en las vacas lecheras, y que tanto el CH4 como las composiciones de la microbiota están parcialmente controladas por el genotipo del hospedador. Las variables agregadas (PC) propuestas podrían ser usadas en programas de mejora de animales para reducir las emisiones de metano en las generaciones futuras., [CA] L'anàlisi del control genètic de l'hoste sobre la seva microbiota s'ha assenyalat recentment com un tema prometedor en diferents camps d'estudi. La relació entre el holobiont hoste-microbioma i els fenotips en bovins de llet podria conduir a nous coneixements en els programes de cria. Dins d'aquest doctorat es van realitzar tesis, estimacions i anàlisis mitjançant diferents enfocaments estadístics amb l'objectiu de desentranyar el control genètic de l'hoste sobre la microbiota en bestiar lleter. A més, es va analitzar el tret de concentració de metà com a fenotip potencial a incloure en el programa espanyol de cria de bestiar lleter. La major abundància relativa de la majoria dels eucariotes (principalment protozous i fongs ciliats) i algunes arquees (Methanobrevibacter spp. Methanothermus spp i Methanosphera spp.) Van ser factors de risc per classificar-se en les categories altes. Es va proposar un conjunt de models d'equacions estructurals (SEM) de tipus recursiu dins d'un marc de cadena Markov Monte Carlo (MCMC) per analitzar conjuntament la relació hoste-metagenoma-fenotip. Es van establir models no recursius com a referència. L'heretabilitat del CH4 es va estimar en 0,12 ± 0,01 en ambdós models, recursius i no recursius. De la mateixa manera, les estimacions d'heretabilitat de l'abundància relativa dels tàxons es van superposar entre models i van oscil·lar entre 0,08 i 0,48. Les correlacions genètiques entre la composició microbiana i el CH4 van oscil·lar entre -0,76 i 0,65 en els models bivariables no recursius i de -0,68 a 0,69 en els models recursius. Dotze matrius de relació de microbiota (K) de diferents mètriques de distància de microbiomes, amb l'objectiu de comparar el seu rendiment dins d'un marc d'estimació de components de variància per CH4 i anàlisi de microbiomes sencers en simulació (n = 1000, 25 rèpliques) i es van realitzar dades reals , considerant quatre possibles models: un model genòmic additiu (GBLUP), un model de microbioma (MBLUP), un model d'efectes genètics i microbiomes (HBLUP) i un model d'efectes d'interacció genètics, microbiomes i genètics × microbiomes (HiBLUP). Es va definir un nou terme "Holobiabilitat" per referir-se a la proporció de la variància fenotípica atribuïble als efectes holobiont del microbioma host. Les estimacions de dades reals mitjançant HiBLUP van variar en funció de la K utilitzada i van oscil·lar entre 0,15-0,17, 0,15-0,21 i 0,42-0,59 per heretabilitat, microbiabilitat i holobiabilitat, respectivament. El conjunt de dades de microbiomes es va agregar mitjançant l'anàlisi de components principals (PCA) en pocs components principals (PC) que es van utilitzar com a proxies del metagenoma principal. Part de la variabilitat condensada en aquestes PC està controlada pel genoma de la vaca, amb estimacions d'heretabilitat per a la primera PC (PC1) de ~ 0,30 a tots els nivells taxonòmics, amb una gran probabilitat (> 83%) de la distribució posterior> 0,20 i amb un 95% més alt interval de densitat posterior (95% HPD) que no conté zero. La majoria de les estimacions de correlació genètica entre PC1 i metà eren grans (>0,70) en tots els nivells taxonòmics, amb una gran part de la distribució posterior (> 82%)> 0,50 i amb un 95% de HPD que no contenia zero. Aquests resultats suggereixen que tot el metagenoma del rumen regula recursivament les emissions de metà en vaques lleteres i que tant el CH4 com les composicions de microbiota estan parcialment controlades pel genotip de l'hoste. Les variables agregades proposades (PC) es podrien utilitzar en programes de cria d'animals per reduir les emissions de metà en les generacions futures., [EN] The analysis of the host genetic control over its microbiota has recently been pointed out as a promising theme in different fields of study. The relationship between the host-microbiome holobiont and phenotypes in dairy cattle could lead to new insights in breeding programs. Within this Ph.D. thesis, estimation and analysis through different statistical approaches were performed aiming to unravel the host genetic control over the microbiota in dairy cattle. Besides, methane concentration trait was analyzed as a potential phenotype to be included in the Spanish dairy cattle breeding program. Higher relative abundance of most eukaryotes (mainly ciliate protozoa and fungi) and some archaea (Methanobrevibacter spp. Methanothermus spp and Methanosphera spp.) were risk factors for being classified in the high categories. a set of structural equation models (SEMs) of a recursive type within a Markov chain Monte Carlo (MCMC) framework was proposed to jointly analyze the host-metagenome-phenotype relationship. Non-recursive models were set as benchmark. Heritability of CH4 was estimated at 0.12 ± 0.01 in both, the recursive and non-recursive, models. Likewise, heritability estimates for the relative abundance of the taxa overlapped between models and ranged between 0.08 and 0.48. Genetic correlations between the microbial composition and CH4 ranged from -0.76 to 0.65 in the non-recursive bivariate models and from -0.68 to 0.69 in the recursive models. Regardless of the statistical model used, positive genetic correlations with methane were estimated consistently for the 7 genera pertaining to the Ciliophora phylum, as well as for those genera belonging to the Euryarchaeota (Methanobrevibacter sp.), Chytridiomycota (Neocallimastix sp.) and Fibrobacteres (Fibrobacter sp.) phyla. Twelve microbiota relationship matrices (K) from different microbiome distance metrics were built, aiming to compare its performance within a variance component estimation framework for CH4 and whole microbiome analysis on simulation (n = 1000, 25 replicates) and real data were performed, considering four possible models: an additive genomic model (GBLUP), a microbiome model (MBLUP), a genetic and microbiome effects model (HBLUP) and a genetic, microbiome and genetic × microbiome interaction effects model (HiBLUP). A new term "Holobiability" was defined to refer to the proportion of the phenotypic variance attributable to the host-microbiome holobiont effects. Estimates from real data using HiBLUP varied depending on the K used and ranged between 0.15-0.17, 0.15-0.21 and 0.42-0.59 for heritability, microbiability and holobiability, respectively. The microbiome dataset was aggregated through Principal Component Analysis (PCA) into few principal components (PCs) that were used as proxies of the core metagenome. Part of the variability condensed in these PCs is controlled by the cow genome, with heritability estimates for the first PC (PC1) of ~0.30 at all taxonomic levels, with a large probability (>83%) of the posterior distribution being > 0.20 and with the 95% highest posterior density interval (95%HPD) not containing zero. Most genetic correlation estimates between PC1 and methane were large (>0.70) at all taxonomic levels, with most of the posterior distribution (>82%) being >0.50 and with its 95%HPD not containing zero. These results suggest that rumen's whole metagenome recursively regulate methane emissions in dairy cows, and that both CH4 and the microbiota compositions are partially controlled by the host genotype. The purposed aggregated variables (PCs) could be used in animal breeding programs to reduce methane emissions in future generations., This research was financed by RTA2015-00022-C03-02 (METALGEN) project from the national plan of research, development and innovation 2013-2020 and the Department of Economic Development and Competitiveness (Madrid, Spain). We thank the regional Holstein Associations and farmers collaborating in the project. Computational support from the High-Performance Computing Centre in Galicia (Spain) is acknowledged. Alejandro Saborío-Montero acknowledges the scholarship from Universidad de Costa Rica for his doctorate studies which partially conducted to the progress of this study.
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- 2022
15. Accuracy of genomic values predicted using deregressed predicted breeding values as response variables.
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Ramírez-Flores, Fernanda, López-Ordaz, Rufino, Domínguez-Viveros, Joel, García-Muñiz, José Guadalupe, and Ruíz-Flores, Agustín
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GENOMES , *PLANT breeding , *PLANT genetics , *GENETIC research , *PHENOTYPES , *GENOTYPES , *GENETICS - Abstract
Highly accurate predicted genetic values must be obtained at an early age to promote rapid genetic progress. The objectives of this study were to compare accuracies (R2) of genomic values (GVs) and to estimate genetic correlation between true genetic values and genomic values obtained using predicted breeding values (EBV) and deregressed EBV (DEBV) as response variables. A first population, effective population size 800 and 100 generations, was simulated using the QMSim program to generate linkage disequilibrium. Thereafter, 20 males and 200 females were used to generate a second 14-generation population, with 6,400 individuals per generation and its corresponding phenotype and genotype in SNP terms. Generations 7 to 14 of the second population were used in several combinations as training (PEn) and evaluation (PEv) subpopulations. GVs, their accuracies, and genetic correlations were obtained using the GenSel and ASREML programs. When PEn was the largest, the mean R2 of GV was the highest, 0.77 ± 0.01. The closer PEn was to PEv, the higher the R2, and correspondingly, the lower the predicted error variance. The trends for R2 and PEV held true for both EBV and DEBV used as response variables. Genetic correlation estimates between true genetic values and GVs varied from 0.41 to 0.53 in the two scenarios studied. They decreased when PEn and PEv were farther apart. There were only slight advantages of using DEBVs as response variables over using EBVs. [ABSTRACT FROM AUTHOR]
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- 2017
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16. Genetic evaluation of dystocia and its relationship with productive and reproductive traits in Holstein cows.
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Salimi, Mohammad Hossein, Hossein-Zadeh, Navid Ghavi, Shadparvar, Abdol Ahad, and Eghbal, Ali Reza
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DYSTOCIA , *HOLSTEIN-Friesian cattle , *MILK yield , *CATTLE breeding , *GENETIC correlations , *HERITABILITY , *CATTLE - Abstract
Background: dystocia is one of the most economically significant secondary traits in dairy cows and has adverse effects on the subsequent survival, health, and performance of mothers and offspring. Objective: the aim of this study was to estimate direct and maternal genetic parameters for calving ease (CE) and its relationship with productive and reproductive traits in Iranian Holstein cows. Methods: data from 1991 through 2011 were collected from the Animal Breeding Center of Iran, and contained 132,831 records of CE, 183,203 records of productive traits including 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305) and 305-d adjusted protein yield (PY305), and 129,199 records of reproductive traits including days open (DO), days to first service (DFS) and calving interval (CI). Univariate and bivariate linear animal models were used for the analysis of traits in two different models on which direct genetic effect (model 1) and direct + maternal genetic effects (model 2) using AI-REML algorithm were included. Results: estimated heritabilities for CE in model 1 were 0.02 in univariate and 0.02-0.03 in bivariate analyses. Direct and maternal heritabilities in model 2 were 0.02 and 0.002 for univariate, and 0.03 and 0.0004-0.006 in bivariate analyses, respectively. Genetic correlations between direct effects of CE with MY305, FY305, and PY305 were -0.99, 0.02 and -0.07 in model 1, and -0.2, -0.02 and -0.13 in model 2, respectively. Conclusion: this study suggested that a selection index that includes both direct and maternal effects should be included in CE breeding programs. [ABSTRACT FROM AUTHOR]
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- 2017
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17. Parámetros genéticos para caracteres asociados a la curva de crecimiento de bovinos Tropicarne.
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Domínguez-Viveros, Joel, Rodríguez-Almeida, Felipe Alonso, Núñez-Domínguez, Rafael, Ramírez-Valverde, Rodolfo, and Ortega-Gutiérrez, Juan Ángel
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- 2017
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18. Genetic parameters for ultrasound-evaluated carcass and body traits in Anglo-Nubian goats
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Tatiana Saraiva Torres, Luciano Silva Sena, Natanael Pereira da Silva Santos, José Elivalto Guimarães Campelo, José Lindenberg Rocha Sarmento, and Luiz A. S. Figueiredo-Filho
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seleção ,calidad de carne ,heritability ,meat quality ,parámetros genéticos ,(co)variance ,genetic parameters ,Anglo-Nubian ,índice de seleção ,selection index ,bayesian inference ,ultrasonografía ,animal production ,parâmetros genéticos ,producción animal ,ultrasonography ,heredabilidad ,genetic correlation ,Breed ,Animal culture ,inferencia Bayesiana ,anglonubian ,qualidade da carne ,goats ,Rump ,selection ,Anglonubian ,Biology ,Genetic correlation ,heredabilidade ,SF1-1100 ,Perimeter ,correlação genética ,Animal science ,Gibbs sampling ,Genetic variation ,Anglonubiana ,canal ,Selection (genetic algorithm) ,(co)variancia ,General Veterinary ,(co)variância ,cabras ,caprinocultura ,Heritability ,inferência Bayesiana ,muestreo de Gibbs ,produção animal ,selección ,carcaça ,Animal Science and Zoology ,gibbs sampling ,correlación genética ,índice de selección ,amostragem de Gibbs ,ultrassonografia ,carcass - Abstract
Background: Meat goat breeding programs should prioritize the identification and selection of genetically superior animals for traits related to meat quality and carcass yield in order to increase the value of the final product. Objective: To estimate (co)variance components and genetic parameters for ultrasound-measured carcass traits, body size and body weight in Anglo- Nubian breed goats raised in the Mid-North region of Brazil. Methods: (Co)variance components and genetic parameters were estimated using the single and two-trait animal model analyses via Bayesian inference for loin eye dimensions (area, length, and depth), sternal fat thickness, rump height, chest circumference and depth, leg perimeter, and body weight. Results: Heritability estimates were higher when two-trait analyses were used. This finding implies that it is possible to recover part of the additive genetic variance included in the residual variance due to the correlation between traits. Genetic correlations between carcass and body size traits showed different magnitudes. On the other hand, genetic correlations between the traits related to muscularity showed high magnitudes. Conclusions: Body weight was not a good indicator of muscularity; therefore, it is not recommended as a criterion for indirect selection to improve carcass traits of Anglo-Nubian goats. Leg perimeter and chest circumference may be important to construct selection indexes in meat goat breeding programs. Resumen Antecedentes: los programas de mejoramiento de caprinos de carne deben priorizar la identificación y selección de animales genéticamente superiores para características relacionadas con la calidad de la carne y rendimiento de la canal, con el fin de agregar valor al producto final. Objetivo: estimar los componentes de (co)varianza y parámetros genéticos para características de canal obtenidas por ultrasonografía, características de tamaño y peso corporal en caprinos de la raza Anglonubiana, criados en la región medio-norte de Brasil. Métodos: los componentes de (co)varianza y parámetros genéticos fueron estimados mediante un modelo animal usando análisis uni y bi-carácter vía metodología Bayesiana para las dimensiones del ojo de lomo (área, profundidad y longitud), grosor de la grasa esternal, altura de la grupa, circunferencia y profundidad torácica, perímetro de la pierna y peso corporal. Resultados: las estimativas de heredabilidad obtenidas a partir del análisis bi-carácteristico fueron mayores que las obtenidas a partir del análisis uni-carácteristico. Este supuesto implica que es posible recuperar parte de la variancia genética aditiva incluida en la variancia residual, debido a la correlación entre las características. Las correlaciones genéticas entre las características de canal y las medidas corporales presentaron diferentes magnitudes. Por otro lado, las correlaciones genéticas entre las características relacionadas con musculatura presentaron alta magnitud. Conclusiones: el peso corporal no fue un buen indicador de musculatura; por eso no es recomendado como criterio de selección indirecta para mejorar la canal de caprinos Anglonubianos. El perímetro de la pierna y la circunferencia del pecho pueden ser importantes para la construcción de índices de selección en programas de mejoramiento de carne caprina. Resumo Antecedentes: programas de melhoramento de caprinos de corte devem priorizar a identificação e seleção de animais geneticamente superiores para características relacionadas à qualidade da carne e rendimento de carcaça, para aumentar o valor ao produto final. Objetivo: estimar componentes de (co)variância e parâmetros genéticos para características de carcaça obtidas por ultrassonografia, características de tamanho e peso corporal em caprinos da raça Anglo-Nubiana criados na região Meio-Norte do Brasil. Métodos: os componentes de (co)variância e parâmetros genéticos foram estimados usando análises uni e bicaracterísticas de um modelo animal via metodologia Bayesiana para área, profundidade e comprimento de olho de lombo, espessura da gordura esternal, altura da garupa, circunferência e profundidade torácica, perímetro da perna e peso corporal. Resultados: as estimativas de herdabilidade obtidas a partir das análises bicaracterísticas foram maiores que as obtidas a partir das análises unicaracterísticas. Esse resultado implica que é possível recuperar parte da variância genética aditiva incluída na variância residual devido à correlação entre as características. As correlações genéticas entre as características de carcaça e as medidas corporais apresentaram magnitudes variáveis. Por outro lado, as correlações genéticas entre as características relacionadas à musculosidade apresentaram altas magnitudes. Conclusões: o peso corporal não se mostrou um bom indicador de muscularidade, de modo que não é recomendado como critério de seleção indireta para melhorar a carcaça de caprinos Anglo-Nubiano. O perímetro de perna e a circunferência torácica podem ser importantes para a construção de índices de seleção em programas de melhoramento de carne caprina.
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- 2020
19. Valoración genética de unidades comportamentales en una ganadería de lidia colombiana
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José Reinel Uribe Ceballos, Daniel José Bartolomé Rodríguez, Jaime Eduardo Muñoz-Flores, María Fernanda González-Valencia, and David Calero Quintero
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Genetic correlation ,Etología ,Correlación genética ,Ethology ,Soil Science ,Horse ,Biology ,Etograma ,Hereditary traits ,Ethogram ,Heritability ,Valores genéticos ,Heredabilidad ,Animal science ,Head position ,Hum ,Unidades comportamentales ,Breeding values ,Behavior traits ,Agronomy and Crop Science - Abstract
Resumen Se diseñó un etograma para desagregar el comportamiento del ganado de lidia, cuantificar la bravura y consolidar la selección. Se analizaron 933 hembras y 787 machos de la ganadería colombiana “Ernesto González Caicedo” (EGC), encaste Santa Coloma, en Popayán, Cauca, Colombia. Las unidades comportamentales (UC) identificadas fueron fijeza (FIJ), distancia de arrancada (DIS), prontitud (PRO), recargar (RGR), ausencia de dolor (DOL), grado de encelamiento (GEN), recorrido (RDO), humillar (HUM), repetir (REP), tipo de embestida (TEM), fondo (FON), fuerza (FZA) y ausencia de defectos (AUD). La información se analizó con el software DeLidia®, desarrollado para esta investigación. Las UC se ajustaron según el efecto de la edad, consanguinidad, peso, sexo, lugar, tipo de festejo, número de varas, torero y picador. Se estimaron índices de herencia, correlaciones fenotípicas y genéticas y valores de cría de sementales. Los valores resultantes de h2 para la UC FZA y REP fueron de 0.06±0.03 y 0.36±0.026, respectivamente, con un promedio de 0.21±0.05 para todas las UC. Todas las rg fueron positivas a excepción de las involucradas con FZA. El valor positivo más bajo de rg fue de 0.1 para GEN y HUM, mientras el más alto fue de 0.79 para FIJ y RDO. Las tendencias de los VG fueron positivas y diferentes de cero (P
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- 2020
20. Genetic parameters between somatic cell score and production traits for Holstein cattle in Southern Brazil
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Gabrieli de Souza Romano, José-Augusto Horst, Luís Fernando Batista Pinto, Victor Breno Pedrosa, and Altair Antônio Valloto
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Animal breeding ,herdabilidade ,Restricted maximum likelihood ,Somatic cell ,produção de leite ,calidad de leche ,componentes de varianza ,heritability ,somatic cell score ,Biology ,mastitis ,milk quality ,SF1-1100 ,Genetic correlation ,milk yield ,Animal science ,genetic parameters ,medicine ,componentes de variância ,Selection (genetic algorithm) ,escore de células somáticas ,Holstein ,General Veterinary ,conteo de células somáticas ,producción de leche ,parâmetros genéticos ,modelo multicaracterística ,Heritability ,medicine.disease ,genetic correlation ,heredabilidad ,qualidade do leite ,Animal culture ,multi-trait model ,Mastitis ,raça Holandesa ,selección genetica ,correlação genéticas ,mastite ,seleção genética ,Trait ,holstein ,variance components ,modelo multicaracteristico ,Animal Science and Zoology ,correlación genética ,parametros geneticos - Abstract
Background: Somatic cell score is an important parameter to predict milk quality and health of cows. However, in countries like Brazil, this trait is still not selected on a large scale, and no genetic parameters are reported in the literature. Objective: To estimate the variance components and genetic parameters for somatic cell score, milk yield, fat yield, protein yield, fat percentage, and protein percentage in Holstein cows. Methods: Records from 56,718 animals were used to estimate variance components, heritability, and genetic correlations using a multi-trait animal model by the REML method. Results: The heritability estimates were 0.19 for somatic cell score, 0.22 for milk yield, 0.26 for fat yield, 0.18 for protein yield, 0.61 for fat percentage, and 0.65 for protein percentage. The estimates of genetic correlations among analyzed traits ranged from -0.50 to 0.82. Conclusion: The low heritability observed for somatic cell score indicates that selection for this trait should result in benefits related to animal health and milk quality, but only in the long term. The low correlation between productive traits and somatic cell score indicates that inclusion of somatic cell score in animal breeding programs does not interfere negatively with the genetic selection for milk yield or solids.Keywords: Holstein; genetic correlation; genetic parameters; heritability; mastitis; milk quality; milk yield; multi-trait model; somatic cell score; variance components. Resumen Antecedentes: El conteo de células somáticas es un parámetro importante para predecir la calidad de la leche y la salud de las vacas. Sin embargo, en países como Brasil, esta característica aún no se selecciona a gran escala y no se reportan parámetros genéticos en la literatura. Objetivo: Estimar los componentes de varianza y parámetros genéticos para el conteo de células somáticas, producción de leche, producción de grasa, producción de proteína, porcentaje de grasa y porcentaje de proteína en vacas de la raza Holstein. Métodos: Se usaron registros de 56.718 animales para estimar los componentes de la varianza, heredabilidad y correlaciones genéticas usando un modelo animal multicaracterístico por medio del método REML. Resultados: Las estimaciones de heredabilidad fueron 0,19 para el conteo de células somáticas, 0,22 para la producción de leche, 0,26 para la producción de grasa, 0,18 para producción de proteína, 0,61 para el porcentaje de grasa y 0,65 para el porcentaje de proteína. Las estimaciones de correlación genética entre las características analizadas variaron entre -0,50 a 0,82. Conclusión: La baja heredabilidad encontrada para conteo de células somáticas demostró que la selección para esta característica podría resultar en beneficios para la salud animal y calidad de la leche, pero sólo a largo plazo. La baja correlación genética existente entre las características productivas y el conteo de células somáticas indica que la inclusión del conteo de células somáticas en programas de selección no interfiere negativamente en la selección genética para la producción de leche o sólidos.Palabras clave: calidad de leche; correlación genética; conteo de células somáticas; componentes de varianza; heredabilidad; Holstein; mastitis; modelo multicaracteristico; parametros geneticos; producción de leche; selección genetica. Resumo Antecedentes: O escore de células somáticas é um parâmetro importante para a predição da qualidade do leite, bem como para a saúde das vacas. No entanto, em alguns países como o Brasil, essa característica não é selecionada em larga escala e não há parâmetros genéticos disponíveis na literatura. Objetivo: Estimar os componentes de variância e parâmetros genéticos para o escore de células somáticas, produção de leite, produção de gordura, produção de proteína, porcentagem de gordura e porcentagem de proteína em vacas da raça Holandesa. Métodos: Foi utilizado um total de 56.718 animais para estimar os componentes de variância, herdabilidade e correlações genéticas, considerando-se o modelo animal multicaracterística por meio do método REML. Resultados: As estimativas de herdabilidade foram de 0,19 para o escore de células somáticas, 0,22 para a produção de leite, 0,26 para a produção de gordura, 0,18 para produção de proteína, 0,61 para a porcentagem de gordura e 0,65 para a porcentagem de proteína. As estimativas de correlação genética entre as características analisadas variaram entre -0,50 a 0,82. Conclusão: A baixa herdabilidade encontrada para o escore de células somáticas demonstrou que a seleção para esta característica poderá resultar em benefícios para a saúde animal e qualidade do leite, porém, somente a longo prazo. A baixa correlação genética existente entre as características produtivas e o escore de células somáticas demonstrou que a inclusão do escore de células somáticas em programas de seleção não causa interferência negativa na seleção genética para a produção de leite ou sólidos.Palavras-chave: componentes de variância; correlação genéticas; escore de células somáticas; herdabilidade; mastite; modelo multicaracterística; parâmetros genéticos; produção de leite; qualidade do leite; raça Holandesa; seleção genética.
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- 2020
21. Correlaciones fenotípicas, ambientales y genéticas en berenjena Phenotypic, genotypic and environmental correlations in eggplant
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Hermes Araméndiz Tatis, Carlos Enrique Cardona Ayala, and Miguel Mariano Espitia Camacho
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Solanum melongena ,solanacea ,calidad de la planta ,rendimiento de fruto ,correlación genética ,solanaceae ,plant quality ,fruit yield ,genetic correlation ,Agriculture - Abstract
En el Centro de Investigaciones Turipaná de la Corporación Colombiana de Investigaciones (Corpoica) (Cereté, Córdoba, Colombia -8° 31' N y 75° 58' O, a 13 m.s.n.m) se estudiaron las correlaciones, ambientales y genéticas entre seis caracteres de 24 cultivares de berenjena (Solanum melongena). Para el efecto se utilizó un diseño de bloques completamente al azar con tres repeticiones y unidades experimentales de 10 m². Los resultados mostraron que las correlaciones fueron de mayor o igual magnitud que las fenotípicas, mientras que las ambientales fueron de escaso valor. El número de frutos y el rendimiento estuvieron genéticamente correlacionados (r = 0.56, P < 0.01), la longitud y la resistencia del fruto mostraron correlación genética negativa (r = -0.68, P < 0.01) y entre el rendimiento y peso de fruto la correlación fue muy baja (r = 0.04). El número de frutos y su peso de frutos se correlacionaron de manera negativa (r =-0.63, P < 0.01). El número de frutos por planta puede ser utilizado como criterio de selección para la obtención de cultivares de berenjena de altos rendimientos.The phenotypic, genotypic and environmental correlations between six characters of 24 cultivars of eggplant (Solanum melongena) were studied in the research centre of Turipaná of Corpoica (Cereté- Córdoba-Colombia -8° 31' N and 75° 58' W, 13 m.a.s.l.). A completely randomized block design was used with three repetitions and experimental units of 10 m2. The analyses showed that genetic correlations were of higher or equal magnitude to the phenotypic correlations, while the environmental ones had low effects on the results. The number of fruits and the yield showed a positive and highly significant (r = 0.56, P < 0.01) genetic correlation. A negative and highly significant (r = -0.68, P < 0.01) genetic correlation was observed between fruit length and fruit strength. No correlation was detected between yield and fruit weight (r = 0.04). Fruit number and fruit weight showed a negative and highly significant genetic correlation (r =-0.63, P < 0.01). It is suggested that the number of fruits per plant could be used as a selection criterium to obtain high yield eggplant cultivars.
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- 2009
22. Genetic parameters of growth traits in Cuban Zebu through the multi-trait animal model and reaction norm model.
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Rodríguez, Yusleiby, de León, Raquel Ponce, and Rodríguez, Manuel
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ZEBUS , *CATTLE genetics , *CATTLE growth , *GENETIC correlations , *NATURE & nurture , *GENETIC models , *CATTLE - Abstract
A multi-trait animal model (15,904 data) and a reaction norm model (13,068 data) were studied, in order to estimate genetic parameters and environmental awareness of the weight at 18 months (P18) and (TDG) of Cuban Zebu during the performance test for future sires. The animals were born between 1981 and 2012 and were the offspring of 295 parents. Multi-trait animal model allowed to obtain the solutions of fixed effect of from the group of contemporaries, heritabilities and genetic tendencies of P18 and trial daily gain TDG. Later, a reaction norm model of sire type was considered, with the group of contemporaries (herd-year-three-month period of animal birth) as fix effect the effect of random regression of sire (cubic, square and linear Legendre polynomials) through an environmental gradient, expressed as solution of fix effect, so a total of 6 environmental classes were created. Estimated values of heritability, through the animal model, were 0.20 ± 0.02 and 0.28 ± 0.02 for TDG and P18, respectively, with a genetic correlation of 0.94 among them. Using the reaction norm model, the estimates varied from 0.13±0.04 to 0.43±0.08, and the highest corresponded to favorable environments or positive gradients. Correlation values, very close to 1, indicate the non-existence of genotype x environment interaction in most of the cases. However, there may be correlations lower than 0.8 in the most unfavorable environment, which indicates that sires selected in favorable environments may not have the same performance after passing to unfavorable environments. [ABSTRACT FROM AUTHOR]
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- 2015
23. Estimation of genetic and phenotypic parameters of some important economic traits in Khazak native hen in Iran.
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Ebrahimzadeh-Allahabad, Ahmad, Mahmodian, Zhila, Pezeshkian, Zahra, and Mollaei, A.
- Abstract
Copyright of Animal Genetic Resources is the property of Cambridge University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2015
- Full Text
- View/download PDF
24. Parámetros genéticos y tendencias genéticas para características de comportamiento en ganaderías de lida mexicanas.
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Domínguez-Viveros, Joel, Rodríguez-Almeida, Felipe Alonso, Núñez-Domínguez, Rafael, Ramírez-Valverde, Rodolfo, and Ruiz-Flores, Agustín
- Subjects
- *
ANIMAL genetics , *HERITABILITY , *BULLFIGHTS , *RANCHES , *ANIMAL herds , *GENETIC correlations - Abstract
The aims of this study were to estimate variance components; calculate heritability (h²) and genetic correlations (rg) predict breeding values (VG) and evaluate their trends over time. Behavior information was analyzed for four Mexican bullfighting ranches: Los Encinos (ENC), Montecristo (MCR), San José (SJO) y Fernando de la Mora (FMO). The analyzed information included was horse tienta (TC), foot tienta (TP), horse bullfight (LC) and foot bullfight (LP). The number of observations ranged from 154 to 2,369, the number of animals in the pedigrees varied from 3,246 to 8,962. Multivariate analyses were conducted using the MTDFREML software. The estimates of h² were from medium to high magnitude, in a range from 0.09±0.05 to 0.47±0.22, and an average of 0.28±0.09. The average of h² by trait was 0.33±0.06 for TC and TP, 0.23±0.14 for LC and 0.27±0.12 for LP. All rg were positive and higher than 0.50, with the exception of TP and LP (0.44±0.38) in FMO, and TC and LP (0.28±0.14) in MCR. The average of the rg within ranches was 0.71±0.14 in MCR, 0.77±0.35 in FMO, 0.78±0.18 in ENC, and 0.85±0.31 in SJO. The trends of the VG were positive and nonzero (P<0.02), with the exception of LP in FMO (P>0.05). The magnitude of the genetic gain per year, as a percentage of the mean, ranged from 0.19% in LC of FMO to 1.5% in TP of ENC. The variability of VG suggests its use in breeding programs to promote greater genetic progress. [ABSTRACT FROM AUTHOR]
- Published
- 2014
25. Path analysis in characteristics of sweet potato clones aiming ethanol yield.
- Author
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Magalhães de Lázari, Thiago, Silveira, Márcio Antônio da, Parente Dourado, Daisy, des Ribeiro de Miranda, Flávia Fernan, and Muraishi, Cid Tacaoca
- Subjects
SWEET potatoes ,PATH analysis (Statistics) ,ETHANOL - Abstract
Copyright of Brazilian Journal of Applied Technology for Agricultural Science / Revista Brasileira de Tecnologia Aplicada nas Ciências Agrárias is the property of Brazilian Journal of Applied Technology for Agricultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
- Full Text
- View/download PDF
26. CONSANGUINIDAD Y ESTIMACIÓN DE PARÁMETROS GENÉTICOS PARA MORFOLOGÍA DEL CABALLO LUSITANO EN MÉXICO.
- Author
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Domínguez-Viveros, J., Rodríguez-Almeida, F. A., and Ortega-Gutiérrez, J. Á.
- Abstract
The Lusitano horse breeders association in Mexico proposed the development of genetic evaluation for morphological traits (VM: headneck (CC), withers (CR), chest (PC), back and loin (DR) and croup (GR)) considered in the selection criteria; however, in earlier studies found high levels of inbreeding (F; 6,6 % average), with constant trend. The objectives were to analyze the effects of F through three indicators (IDF: F of animal (IF); average correlation coefficient (CRP); and, change rate of F (ΔF)) on the average performance, the estimate of heritability (h2) and genetic correlation (rg) for the VM. Including alternately the IDF as covariate of first order were performed four univariate analysis (UNV) for each VM, and four multivariate analyses with the five VM. The covariate solutions of IDF were equal to zero (p>0,05). The h2 with the UNV ranged from 0,08 (DR) to 0,30 (CC), the general average was 0,18. The maximum change with IDF was 0,01. In the MUV, the h2 ranged from 0,11 to 0,35, the general average was 0,198; in the rg, the average without IDF was 0,53, in the interval of 0,01 to 0,97; with IDF the average was 0,59, with estimates above 0,20. The h2 of UNV vs. MUV without IDF were similar. For PC and GR the h2 decreased 0,03 of UNV to MUV with IDF; to contrast of CC, CR y DR with increments of 0,06. Inside MUV, for CC, CR and DR the h2 increased with IDF, with more effect CRP; however, in PC and GR decreased, with more effect of F. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
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27. Path analysis under multiple-trait BLUP: application in the study of interrelationships among traits related to cotton fiber length
- Author
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Francisco José Correia Farias, João Romero do Amaral Santos de Carvalho Rocha, Larissa Pereira Ribeiro Teodoro, Paulo Eduardo Teodoro, Luiz Joaquim Castelo Branco Carvalho, Leonardo Lopes Bhering, Marcos Deon Vilela de Resende, and Rodrigo Silva Alves
- Subjects
Mixed model ,Restricted maximum likelihood ,Gossypium hirsutum ,selección genética ,Plant Science ,Best linear unbiased prediction ,Residual ,Genetic correlation ,Food processing and manufacture ,lcsh:Agriculture ,Statistics ,Path analysis (statistics) ,Selection (genetic algorithm) ,Mathematics ,lcsh:TP368-456 ,lcsh:S ,Agriculture ,genotipo x ambiente ,TP368-456 ,lcsh:Food processing and manufacture ,selección genética ,correlación genética ,Trait ,correlación genética ,Modelo mixto ,Agronomy and Crop Science - Abstract
Multi-trait best linear unbiased prediction (BLUP) is, generally, the most appropriate method to genetic evaluation because it considers the genetic and residual correlations among traits and conduct to higher selection accuracy. Thus, the present study aimed to identify traits correlated to the fiber length via path analysis under multi-trait BLUP for the cotton breeding. To this end, thirty-six elite lines were evaluated in three environments and phenotyped for many traits related to fiber quality and agronomic traits. Variance components were estimated via residual maximum likelihood (REML). The genetic correlation coefficients among traits were obtained through mixed model output, and to graphically express these results a correlation network was built. Subsequently, we performed path analysis considering fiber length as a principal dependent variable. Genetic parameters obtained by multi-trait BLUP model indicate that the phenotypic variance for most traits is mostly composed of residual effects, which reinforces the need for using more accurate statistical methods such as multi-trait BLUP. The results found for genetic correlations and path analysis under multi-trait BLUP reveal the difficulty of selection based on important fiber quality traits, especially fiber length, since most traits show very low cause-and-effect relationship, and other important traits present undesirable cause-and-effect relationship. Highlights Multiple-trait BLUP is the most appropriate method to predict genetic values. This is the first study in cotton to perform path analysis under multiple-trait BLUP. The findings of this study indicate that there is no genotype presenting all desirable traits.
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- 2020
28. Single- and multiple-trait BLUP in genetic selection of parents and hybrids of grain sorghum
- Author
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Nadson Oliveira de Souza, Rodrigo Silva Alves, Paulo Eduardo Teodoro, Lidiane Aparecida Silva, Flávio Dessaune Tardin, Aisy Baldoni Tardin, Marcos Deon Vilela de Resende, and Leonardo Lopes Bhering
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Fitomejoramiento ,Genetic correlation ,lcsh:TP368-456 ,Dialelo parcial ,lcsh:S ,Correlación genética ,food and beverages ,Agriculture ,TP368-456 ,Food processing and manufacture ,Plant breeding ,lcsh:Agriculture ,dialelo parcial ,lcsh:Food processing and manufacture ,correlación genética ,Modelos mixtos ,Partial diallel ,heterosis ,Heterosis ,correlación genética ,fitomejoramiento ,Mixed model methodology ,modelos mixtos - Abstract
To increase yield, breeding programs must search for innovative and efficient methodologies for the development and selection of superior genotypes. Therefore, this study aimed to compare the single- and multiple-trait best linear unbiased prediction (BLUP) in genetic selection of parents and hybrids of grain sorghum. For this, an experiment conducted in alpha-lattice design with two replications was used. Flowering time (FT), plant height (PH), and grain yield (GY) were evaluated in 502 grain sorghum hybrids obtained by the cross of ten restorer lines and 54 male-sterile lines. Variance components were estimated via restricted maximum likelihood (REML). Significant effects of restorer lines, of male-sterile lines, and of specific combining ability were detected by the likelihood ratio test (LRT). The estimates of variance components, genetic parameters, and correlations were similar when obtained via single- and multiple trait BLUP. Considering hybrids, the multiple-trait BLUP resulted in slightly higher predicted selection gain for the three evaluated traits and, therefore, can be efficiently applied in the genetic selection of grain sorghum. Para incrementar el rendimiento, los programas de mejoramiento deben buscar metodologías innovadoras y eficientes para el desarrollo y la selección de genotipos superiores. De esta forma, este estudio tuvo como objetivo comparar la mejor predicción lineal no viciada (BLUP) mono y múltiple característica, en la selección genética de parentales e híbridos de sorgo granelero. Para esto, fue usado un experimento con diseño alfa latice con dos repeticiones. Se evaluó el tiempo de floración (FT), la altura de planta (AP) y el rendimiento de granos (GY) en 502 híbridos de sorgo, obtenidos por el cruzamiento entre diez líneas restauradoras y 54 líneas macho estériles. Los componentes de varianza se estimaron mediante el método de máxima verosimilitud restringida (REML). Observamos que varias veces el BLUP múltiple característica da como resultado estimaciones de correlación genética más precisas. En este trabajo, se encontraron mayores correlaciones entre FT y GY a través de BLUP múltiple característica. Estos resultados llevaron a mayores ganancias genéticas para la selección de híbridos en comparación con BLUP mono característica.
- Published
- 2019
29. Parámetros genéticos de las características andrológicas en la especie bovina.
- Author
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Silva, M. R., Pedrosa, V. B., Silva, J. B. C., Herrera, L. G. G., Eler, J. P., and Albuquerque, L. G.
- Subjects
ANIMAL genetics ,ANDROLOGY ,BOS ,HERITABILITY ,GENETIC correlations ,FERTILITY ,CATTLE herding ,PHYSIOLOGY ,CATTLE - Abstract
Copyright of Archivos de Medicina Veterinaria is the property of Universidad Austral de Chile, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2012
- Full Text
- View/download PDF
30. GANANCIA GENÉTICA ESPERADA EN Acacia mangium EN LOS CHILES, ZONA NORTE DE COSTA RICA.
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Pavlotzky-Blank, Benjamín and Murillo-Gamboa, Olman
- Subjects
- *
MANGIUM , *PROGENY tests (Botany) , *PLANT growth , *GENETIC research , *PLANT genetics , *PROVENANCES of cultivated plants , *GENETIC correlations , *PLANTS - Abstract
An Acacia mangium Wild. progeny test conformed by 25 families was evaluated with the objective of selecting the best materials in growth and stem quality. The trial was established in Los Chiles, Northern Costa Rica in 2006, and evaluated in 2007 and in 2010. Genetic materials came from breeding selections obtained by GENFORES, a tree improvement and gene conservation cooperative, in Costa Rica and Colombia. Each family was represented by 48 progenies, split in four pairs randomly distributed within each of the six blocks of the trial. DBH, DBH increment, survival rate, number of commercial logs per tree, forking, forking height and log quality of the first four logs were evaluated. Wood commercial volume per tree and hectare was estimated. Data was analyzed with SELEGEN software from EMBRAPA in order to obtain all genetic parameters for the breeding population. All traits showed family mean heritability values over 0.68. Genetic gain in commercial volume per hectare was estimated as 40.8%, when selecting as progenitors the two best individuals from the top twelve families at four year old, which corresponds to an expected commercial volume/ ha at this age of 91.65 m³/ha, based on a growth rate of 22.9 m³/ha/year. The two columbian provenances are significantly superior to the rest of the evaluated materials. Genetic correlations among traits show diameter growth rate early expressed in this tree species, therefore, there is a potential usage of this trait in early selection thus, shortening future selections. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
31. SELECCIÓN DE LÍNEAS DE PIMIENTO (Capsicum annuum L.) PARA SER UTILIZADAS COMO PROGENITORAS EN LOS PROGRAMAS DE OBTENCIÓN DE HÍBRIDOS.
- Author
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Rodríguez, Yaritza and Depestre, T. L.
- Published
- 2005
32. Evaluación genética de 14 variedades de crisantemo (Chrysanthemum X Morifolium Ramat.) y estimación del valor genético esperado para 6 rasgos de importancia agronómica y económica
- Author
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Munera-Manco, Mateo, Calvo-Cardona, Samir Julián, and Universidad Católica de Oriente. Facultad de Posgrados
- Subjects
Genetic correlation ,Recursos genéticos vegetales ,Semillas transgénicas ,Chrysanthemum ,Genética vegetal ,Correlación genética ,Phenotypic correlation ,Genetic parameters ,Parámetros genéticos ,Heritability ,Heredabilidad ,Selección indirecta ,Correlación fenotípica ,Mejoramiento selectivo de las plantas ,Indirect selection - Abstract
Varios trabajos han reportado la naturaleza cuantitativa de la herencia de la resistencia a nematodos del género Meloidogyne en plantas y, a pesar de que es una enfermedad de importancia en la producción de Crisantemo, no hay trabajos que reporten la estimación de parámetros genéticos para el rasgo y su correlación genética con otros rasgos de importancia agronómica o económica. Este trabajo tuvo como objetivo realizar una evaluación genética de 14 variedades de crisantemo, con el fin de estimar los parámetros genéticos y los valores genéticos esperados para 6 rasgos de importancia agronómica y comercial. Para este estudio se sembraron 14 variedades de crisantemo con 5 individuos por variedad, bajo condiciones de invernadero, en una parcela con altas poblaciones de nematodos del género Meloidogyne (entre 400-600 individuos en 100 gramos de suelo), durante dos temporadas de producción, entre 2018-2019. Allí se midió la altura en punto de corte, el peso del tallo a 70 cm de longitud, el número de flores por tallo, el número de nudos por gramo de raíz, el tiempo de respuesta y la vida en florero. También, se estimaron los parámetros genéticos (heredabilidad y correlación genética), los valores genéticos esperados y las correlaciones fenotípicas para todos los rasgos, usando inferencia bayesiana. Como resultado de la investigación se encontraron valores de heredabilidad entre h²=0.21 y h²=0.48 para todos los rasgos. Además, se encontró una correlación genética alta y negativa entre el rasgo vida en florero y severidad de la infección (-0.63). Estos resultados demuestran la posibilidad de realizar selección indirecta de rasgos en los programas de mejoramiento genético en Crisantemo. Several papers have reported the quantitative nature of the inheritance of tolerance to nematodes of the genus Meloidogyne in plants and, despite, it is an important pest in chrysanthemum production there are no research on the estimation of genetic parameters for the trait and its genetic correlation with other agronomic or economic traits. The objective of this work was to carry out a genetic evaluation of 14 varieties of chrysanthemum in order to estimate the genetic parameters and the expected genetic values of 6 traits of agronomic and commercial importance. Fourteen varieties of chrysanthemum were planted under greenhouse conditions with 5 individuals per variety in a plot with high populations (between 400-600 individuals in 100 grams of soil) of nematodes from the Meloidogyne´s genus during two seasons of production between 2018-2019; height was measured at harvest point, weight of the stem was measured at 70cm length; number of flowers per stem, number of nodes per gram of root, response time and vase life were, also, measured. Genetic parameters (heritability and genetic correlation), expected genetic values and phenotypic correlations for all traits were estimated using Bayesian inference. Mean heritability values were found for all the traits (h² = 0.21-0.48) and a high and negative genetic correlation was found between the vase life and the severity of the infection (-0.63). These results show the possibility of indirect selection of traits in Chrysanthemum breeding programs. Rionegro
- Published
- 2019
33. Genetic evaluation for weight traits in commercial Brahman cattle
- Author
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Bedoya O, Christian, Alzate R, Joyany, Ángel C, Juan, Escobar R, Carlos, and Calvo C, Samir
- Subjects
modelo animal ,beef cattle ,genetic progress ,Correlación genética ,Animal model ,ganado de carne ,CAB) [progreso genético (Fuente] ,heredabilidad ,genetic correlation ,CAB) [heritability (Source] - Abstract
RESUMEN Objetivo. Evaluar genéticamente las características de peso al nacimiento y peso al destete en una población de ganado Brahman comercial. Materiales y métodos. Se analizaron 1.015 registros de peso al nacimiento (PN) y peso al destete ajustado a los 270 días (PA270) de crías entre los años 2002 y 2014 pertenecientes a la hacienda La Envidia, ubicada en el município de Planeta Rica, Córdoba. Se utilizó un modelo animal bi-carácter que incluyó efectos fijos de sexo, mes, año y edad al destete, efecto genético aditivo y el efecto materno, estimando los parámetros genéticos con el software MTDF-REML. Resultados. Se encontró un promedio para PN de 29.62±3.13kg y coeficiente de variación (CV) del 10.6%. La media para PA270 fue de 216.713±26.97 kg y CV 12.5%. Los estimados de heredabilidad directa (h2d) fueron de 0.44±0.14 y 0.39±0.12 para PN y PA270, respectivamente. La heredabilidad materna (h2m) fue de 0.09±0.092 y 0.42±0.087 para PN y PA270, respectivamente. La correlación genética y fenotípica estimada entre las características evaluadas fue de 0.11 y 0.13, respectivamente; con progreso genético por ano para PN de -2.02 kg y 7.81 kg para PA270. Conclusiones. Las estimaciones de heredabilidad indican la existencia de variabilidad genética aditiva directa, evidenciando la oportunidad de ganancia genética por medio de selección. Sin embargo, las características de peso al nacer y peso del destete presentan gran influencia del ambiente, por lo cual se debe poner especial atención al manejo y la nutrición de las hembras durante la gestación y de los terneros desde el nacimiento hasta el destete. ABSTRACT Objective. Evaluate genetically the traits of birth weight and weaninq weight in commercial Brahman cattle. Materials and methods. A total of 1.015 records of birth weight (BWT) and weaning weight adjusted to 270 days (WW270), were evaluated. Data correspond to the offspring born between 2002 and 2014 belonging to "La Envidia" farm, located in the municipality of Planeta Rica, Córdoba. A bi-character animal model that included, additive genetic effect, maternal effect and sex, month, year and age at weaning as fixed effects, was used. Genetic parameters were estimated using the MTDF-REML software. Results. The average and coefficient of variation (CV) of BWT was 29.62±3.13 kg and 10.59%, respectively. The mean and CV for WW270 was 216.71±26.97 kg and 12.45%, respectively. The estimates of direct heritability were 0.44±0.143 and 0.39±0.12 for BWT and WW270, respectively. Maternal heritability was 0.09±0.092 and 0.42±0.087 for BWT and WW270, respectively. The estimated genetic and phenotypic correlation between the evaluated characteristics was 0.11 and 0.13, respectively; with genetic progress per year of -2.02 kg for BWT and 7.81 kg for WW270. Conclusions. The estimations of heritability indicate the existence of direct additive genetic variability, evidencing the opportunity of genetic gain through selection. However, environment have a great influence on birth weight and weaning weight traits, which is why special attention should be paid to the handling and nutrition of females during pregnancy and of calves from birth to weaning.
- Published
- 2019
34. Parâmetros produtivos e genéticos da produção in vitro de embriões em bovinos Nelore no Acre
- Author
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PINHEIRO, A. K. and Antônia Kaylyanne Pinheiro, Universidade Federal do Acre (Ufac).
- Subjects
Gado de Corte ,Eficiência Reprodutiva ,Genetic correlation ,Reprodução Animal ,Animal reproduction ,Correlación genética ,Gado Nelore ,Beef cattle ,Desempeño reproductivo ,In vitro culture ,Amazonia Occidental ,Acre ,Heredabilidad ,Cultura In Vitro ,Reproductive performance ,Nellore ,Raza de bovinos Nelore ,Heritability ,Ganado de carne ,Cultivo in vitro ,Reproducción de animales ,Parâmetro Genético ,Amazônia Ocidental ,Western Amazon - Abstract
No Acre, a partir do ano 2000, verifica-se aumento na demanda para produção in vitro de embriões. Contudo, diversos fatores ambientais e genéticos interferem na produção de oócitos, embriões e taxa de prenhez. O objetivo deste trabalho foi avaliar os parâmetros produtivos e genéticos da produção in vitro de embriões da raça Nelore no Acre. Foram utilizados dados de 1.292 sessões de aspirações foliculares realizadas em 571 doadoras, fornecidos pela empresa In Vitro Acre. Foram analisadas as variáveis: Número Total de Oócitos, Número Total de Embriões Clivados, Número Total de Embriões Produzidos e Número Total de Prenhez, e os Percentuais de Conversão de Oócitos para Embriões, Conversão de Embriões para Prenhez e Conversão de Oócitos para Prenhez. Foram calculados os parâmetros produtivos, os efeitos genéticos e não genéticos que influenciam na expressão de cada uma delas. Observou-se médias gerais para número de oócitos, embriões e prenhezes por aspiração/vaca de 30,05; 9,82 e 3,03; respectivamente. Para as taxa de Conversão de Oócito/Embrião; Embrião/Prenhez e Oócito/Prenhez obtiveram-se valores de 34,19; 38,39 e 10,68%, respectivamente. Os efeitos não genéticos significativos foram: efeito de fazenda, touro, idade da doadora, ano e tipo de sêmen para todas as variáveis avaliadas e efeito de estação do ano para as variáveis Número Total de Embriões Clivados e Número Total de Prenhez. Observou-se herdabilidade de magnitude baixa a média, indicando variabilidade genética para as variáveis relacionadas à produção de oócitos, embriões e prenhezes. As correlações fenotípicas e genéticas estimadas entre as variáveis Número Total de Oócitos, Embriões e Prenhezes foram positivas e de alta magnitude indicando que a seleção para aumento na produção de oócitos resulta em aumento na produção de embriões e nas taxas de prenhezes. Conclui-se que há variabilidade genética justificando a seleção de doadoras para produção de oócitos, embriões e prenhezes e que atenção deve ser dada a melhoria dos efeitos ambientais para aumentar a eficiência da produção in vitro de embriões. In Acre, from the year 2000, there is an increase in the demand for in vitro production of embryos. However, several environmental and genetic factors interfere in the production of oocytes, embryos and pregnancy rate. The objective of this work was to evaluate the productive and genetic parameters of the in vitro production of Nelore embryos in Acre. Data from 1,292 follicular aspiration sessions were used in 571 donors, provided by In Vitro Acre company. The following variables were analyzed: Total Oocytes, Total Number of Clotted Embryos, Total Number of Produced Embryos and Total Number of Pregnancy, and the Percentages of Oocyte Conversion for Embryos, Conversion of Embryos for Pregnancy and Conversion of Oocytes for Pregnancy. The productive parameters and the genetic and non-genetic effects that influence the expression of each of them were calculated. Overall averages were observed for number of oocytes, embryos and pregnancy per suction/cows of 30.05; 9.82 and 3.03; respectively. For the rates of Oocyte / Embryo Conversion; Embryo / Pregnancy and Oocyte / Pregnancy, the values were 34.19; 38.39 and 10.68%, respectively. The non-genetic significant effects were: farm effect, bull, donor age, year and type of semen for all variables evaluated and season of the year effect for the variables Total Number of Clotted Embryos and Total Number of Pregnancy. Heritability of low to medium magnitude was observed, indicating genetic variability for the variables related to the production of oocytes, embryos and pregnancy. The estimated phenotypic and genetic correlations among the variables Total Number of Oocytes, Embryos and Pregnancy were positive and of high magnitude, indicating that the selection for increase of oocyte production results in an increase of embryo production and in pregnancy rates. It is concluded that there is genetic variability justifying the selection of donors for oocyte, embryo and pregnancy production and that attention should be given to improving environmental effects to increase the efficiency of in vitro embryo production. Keywords: Made available in DSpace on 2020-01-21T00:33:43Z (GMT). No. of bitstreams: 1 26951.pdf: 1074326 bytes, checksum: 9ab8cfbc039bb6688e9fba6b27d33671 (MD5) Previous issue date: 2019 Dissertação (Mestrado em em Ciência Animal) - Programa de Pós-graduação em Sanidade e Produção Animal Sustentável na Amazônia Ocidental, Universidade Federal do Acre, Rio Branco. Orientador: José Marques Carneiro Junior.
- Published
- 2019
35. GANANCIA GENÉTICA ESPERADA E INTERACCIÓN GENOTIPO-AMBIENTE EN Acacia mangium EN LA ZONA NORTE DE COSTA RICA.
- Author
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Pavlotzky, Benjamín and Murillo, Olman
- Subjects
- *
MANGIUM , *GENOTYPE-environment interaction , *TREE growth , *PROGENY tests (Botany) , *GENETIC correlations , *PLANTS - Abstract
Two Acacia mangium Willd. progeny tests were evaluated, pursuing an increment in the profitability of commercial plantations. The 25 open-pollinated families were established in Los Chiles and San Carlos, northern region of Costa Rica, in year 2006, and evaluated in 2007 and in 2010. Genetic material came from plus tree selections obtained by GENFORES, a costarican tree-improvement and gene-conservation cooperative. In each trial, families were represented by 48 progenies, planted in 4 pairs randomly distributed within each of the 6 blocks. In 2010, DBH, survival rate, commercial number of logs per tree, forking, forking height and log quality in the first 4 logs, were evaluated. Based on these measurements, wood commercial volume per tree and per hectare were estimated. Data was analyzed with SELEGEN software from EMBRAPA, Brasil, in order to determine all genetic parameters of the breeding population. All traits evaluated showed family mean heritability values over 0.46. Genetic gain in commercial volume per hectare was estimated as 55.8%, when selecting as parents the 2 best individuals from the top 12 families, which would correspond to an expected commercial volume⋅ha-1, at 4 years age, of 78.93 m³⋅ha-1 (around 20 m³⋅ha-1⋅year-1). The 2 Colombian provenances were significantly superior in growth to the rest of the evaluated materials. No significant gene-environment interaction was observed between both sites. Genetic correlations among evaluated traits showed that diameter growth rate is expressed early in this tree species, thus could be used in shortening future selections. [ABSTRACT FROM AUTHOR]
- Published
- 2014
36. Avaliação genética de distocia e sua relação com características produtivas e reprodutivas em vacas da raça Holandesa
- Author
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Hossein Salimi, Mohammad, Hossein-Zadeh, Navid Ghavi, Shadparvar, Abdol Ahad, and Eghbal, Ali Reza
- Subjects
desempenho produtivo ,calving difficulty ,dairy cow ,productive performance ,dificultad de parto ,parâmetros genéticos ,dificuldade de parto ,genetic correlation ,correlação genética ,genetic parameters ,parámetros genéticos ,correlación genética ,rendimiento productivo ,vaca lechera ,vaca de leiteria - Abstract
Background: dystocia is one of the most economically significant secondary traits in dairy cows and has adverse effects on the subsequent survival, health, and performance of mothers and offspring. Objective: the aim of this study was to estimate direct and maternal genetic parameters for calving ease (CE) and its relationship with productive and reproductive traits in Iranian Holstein cows. Methods: data from 1991 through 2011 were collected from the Animal Breeding Center of Iran, and contained 132,831 records of CE, 183,203 records of productive traits including 305-d adjusted milk yield (MY305), 305-d adjusted fat yield (FY305) and 305-d adjusted protein yield (PY305), and 129,199 records of reproductive traits including days open (DO), days to first service (DFS) and calving interval (CI). Univariate and bivariate linear animal models were used for the analysis of traits in two different models on which direct genetic effect (model 1) and direct + maternal genetic effects (model 2) using AI-REML algorithm were included. Results: estimated heritabilities for CE in model 1 were 0.02 in univariate and 0.02-0.03 in bivariate analyses. Direct and maternal heritabilities in model 2 were 0.02 and 0.002 for univariate, and 0.03 and 0.0004-0.006 in bivariate analyses, respectively. Genetic correlations between direct effects of CE with MY305, FY305, and PY305 were -0.99, 0.02 and-0.07 in model 1, and -0.2, -0.02 and -0.13 in model 2, respectively. Conclusion: this study suggested that a selection index that includes both direct and maternal effects should be included in CE breeding programs. Resumen Antecedentes: la distocia es uno de los rasgos secundarios económicamente más significativos en las vacas lecheras y tiene efectos adversos sobre la posterior supervivencia, salud y el rendimiento de las madres e hijos. Objetivo: estimar parámetros genéticos directos y maternos para facilidad de parto (CE) y su relación con las características productivas y reproductivas en vacas Holstein iraníes. Métodos: se recogieron datos desde 1991 hasta 2011 en el Centro de Reproducción Animal de Irán, que contenían 132.831 registros de la CE, 183.203 registros de características productivas, incluyendo 305-d ajustado la producción de leche (MY305), 305-d de rendimiento graso ajustado (FY305) y 305-d de producción de proteína ajustada (PY305), y 129.199 registros de características reproductivas, incluyendo días abiertos (DO), días al primer servicio (DFS) y el intervalo entre partos (CI). Se utilizaron modelos animales lineales univariantes y bivariantes para el análisis de rasgos en dos modelos diferentes en los que se incluyeron el efecto genético directo (modelo 1) y los efectos genéticos maternos directos + (modelo 2) usando el algoritmo AI-REML. Resultados: las heredabilidades estimadas para la CE en el modelo 1 fueron 0,02 en uni y 0,02-0,03 en los análisis bivariados. Las heredabilidades directas y maternas en el modelo 2 fueron 0,02 y 0,002 para univariado, y 0,03 y 0,0004 a 0,006 en el análisis bivariado, respectivamente. Las correlaciones genéticas entre los efectos directos de la CE con MY305, FY305 y PY305 fueron -0,99, 0,02 y -0,07 en el modelo 1 y -0,2, -0,02 y -0,13 en el modelo 2, respectivamente. Conclusión: este estudio sugiere que un índice de selección que incluye tanto los efectos directos y maternos se debe incluir en los programas de mejoramiento de la CE. Resumo Antecedentes: distocia é uma das características secundárias economicamente mais significativas em vacas leiteiras e tem efeitos adversos sobre a subsequente sobrevivência, saúde e desempenho de mães e filhos. Objetivo: o objetivo deste estudo foi estimar parâmetros genéticos direto e maternos para facilidade de parto (CE) e sua relação com características produtivas e reprodutivas em vacas da raça Holandesa iranianos. Métodos: dados de 1991 a 2011 foram coletados a partir do Centro de Melhoramento Animal do Irã, estes continham 132.831 registros da CE, 183.203 registros de características produtivas, incluindo 305-d rendimento ajustado leite (P305), 305-d produção de gordura ajustada (FY305) e 305-d rendimento ajustado proteína (PY305), e 129.199 registros de características reprodutivas, incluindo jornadas de portas abertas (DO), dias para o primeiro serviço (DFS) e intervalo entre partos (CI). Modelos animais lineares univariados e bivariados foram utilizados para a análise de características em dois modelos diferentes em que foram incluídos efeito genético direto (modelo 1) e efeitos genéticos maternos diretos + (modelo 2) usando o algorítmo AI-REML. Resultados: a herdabilidade estimada para CE no modelo 1 foi 0,02 na análise univariada e 0,02-0,03 na análise bivariada. A herdabilidade direta e materna no modelo 2 foi 0,02 e 0,002 para univariada, e 0,03 e 0,0004-0,006 na bivariada, respectivamente. As correlações genéticas entre os efeitos diretos da CE com P305, FY305 e PY305 foram -0,99, 0,02 e -0,07 no modelo 1 e -0,2, -0,02 e -0,13 no modelo 2, respectivamente. Conclusão: este estudo sugere que um índice de seleção que inclua efeitos diretos e maternos deve ser incluído em programas de melhoramento para CE.
- Published
- 2017
37. Correlaciones genotípicas, fenotípicas y ambientales, y análisis de sendero en tomate de árbol (Cyphomandra betacea Cav. Sendt.)
- Author
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Liz Katherine Lagos Santander, Franco Alirio Vallejo, Tulio César Lagos Burbano, and DAVID DUARTE
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Fitomejoramiento ,phenotypic correlation ,Genetica ,Agronomia ,Análisis de sendero ,lcsh:S ,genetic correlation ,63 Agricultura y tecnologías relacionadas / Agriculture ,lcsh:Agriculture ,mejoramiento genetico ,Cyphomandra betacea ,path analysis ,6 Tecnología (ciencias aplicadas) / Technology ,correlación genética ,correlación fenotípica ,environmental correlation ,correlación ambiental - Abstract
En el estudio se evaluaron diferentes componentes de producción y se estimaron las correlaciones fenotípicas, genéticas y ambientales, considerando nueve variables relacionadas con el tamaño y la calidad del fruto de tomate de árbol (Cyphomandra betacea Cav. Sendt.); igualmente se establecieron los efectos directos e indirectos de las variables componentes de calidad sobre el peso del fruto. Para el efecto se utilizaron los datos existentes de 81 híbridos (72 híbridos interpoblacionales y nueve testigos) dispuestos en tres repeticiones, en condiciones del departamento de Nariño, Colombia. Los resultados obtenidos indicaron que las correlaciones genotípicas fueron superiores a las fenotípicas y ambientales. El peso de fruto (PF) presentó las mayores correlaciones genéticas con el peso de semilla por fruto (rG = 0.97) y con el peso de pulpa más semilla (rG = 0.92). El análisis de sendero con base en correlaciones genotípicas mostró que el peso de pulpa más semilla fue la variable que tuvo el mayor efecto directo sobre el PF (1.353). Esto demuestra que una selección por peso de fruto da como resultado un aumento en peso de pulpa más semilla. Teniendo en cuenta las correlaciones fenotípicas, este análisis permitió establecer que los efectos directos de peso de semilla de fruto (PSF) y peso de pulpa más semilla (P +S) (1.166 y 0.743, respectivamente) son los que más contribuyen al PF. The study different production components were evaluated and phenotypic, genetic and environmental correlations were estimated, considering nine characters related to the size and quality of tomato tree fruit (Cyphomandra betacea Cav Sendt.), also settled the direct and indirect effects of the component variables of quality on fruit weight. To effect the existing data of 81 hybrids (72 interpopulation hybridsand nine witnesses) arranged in three replications, under the Department of Nariño, Colombia were used. The results indicated that genotypic correlations were higher than phenotypic and environmental. The fruit weight (PF) presented the highest genetic correlations with seed weight per fruit (rG = 0.97) and with more seed pulp weight ( rG = 0.92 ) . Path analysis based on genotypic correlations showed 216 that more seed pulp weight was the variable that had the most direct effect on the PF (1.353). This shows that a selection of the fruit weight results in an increase in weight of pulp more seed. Given the phenotypic correlations, this analysis established that the direct effects of seed weight of fruit (PSF)and more seed pulp weight (P + S ) (1.166 and 0.743 , respectively ) are the largest contributors to PF.
- Published
- 2013
38. Etograma para la cuantificación de la bravura y la evaluación genética en hatos de lidia
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Calero Quintero, David, Muñoz Florez, Jaime Eduardo, Daniel, Bartolomé Rodriguez, and José Reinel, Uribe Ceballos
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Genetic correlation ,Etología ,Correlación genética ,Ethology ,Etograma ,Ethogram ,63 Agricultura y tecnologías relacionadas / Agriculture ,Heritability ,Valores genéticos ,Heredabilidad ,Unidades comportamentales ,59 Animales / Animals ,Breeding values ,Behavior traits - Abstract
Se diseñó un etograma para desagregar el comportamiento del ganado de lidia durante las faenas de tienta y de lidia, con el propósito de cuantificar la bravura y dar mayor objetividad en la selección. El estudio se realizó en la ganadería colombiana de Ernesto González Caicedo, con encaste Santa Coloma, ubicada en el municipio de Popayán. Las variables etológicas identificadas fueron: fijeza, prontitud, distancia de arrancada, recargar, ausencia de dolor, grado de encelamiento, recorrido, humillar, repetir, tipo de embestida, y fuerza. El número de individuos analizados fue 1720 (933 hembras y 787 machos). Toda la información se recopiló y procesó con el software para ganaderías bravas DeLidia (v. 2.0.1505), desarrollado especialmente para este estudio y con el que se evaluó el comportamiento de los animales durante la tienta y la lidia. Se evaluaron los efectos que sobre las variables etológicas tuvieron la consanguinidad, el sexo, lugar, tipo de festejo, número de varas y torero. Se estimaron para cada una de ellas las frecuencias fenotípicas, los índices de herencia, las correlaciones fenotípicas, genéticas, y los valores de cría de los sementales empleados. Los valores de h2 fueron de bajos a moderados, entre 0.06±0.03 y 0.36±0.026, correspondientes a las unidades comportamentales de FZA y REP; el promedio de todas las unidades fue de 0.21±0.05. Todas las rg fueron positivas a excepción de las involucradas con FZA que dieron negativas; el valor positivo más bajo de rg fue de 0.1 para GEN y HUM, mientras el más alto fue de 0.79 para FIJ y RDO. Las tendencias de los VG fueron positivas y diferentes de cero (P0.01), excepto FZA que dio negativo (-0.004±0.0004). Las ganancias por año, como parte porcentual de la media, estuvieron entre -0.191 % para FZA y 1.024% para REP. Los resultados encontrados para h2 y VG en este estudio sugieren su utilidad en programas de selección, favoreciendo un mayor progreso genético. //Abstract: An ethogram was designed to disaggregate the behavior of fighting cattle through tienta and lidia not only to quantify the bravery but also have greater objectivity in the selection. The study was conducted in the Colombian Farm of Ernesto Gonzalez Caicedo, mating with a line from Santa Coloma, located in the city of Popayan. The ethological variables identified were: concentration, readiness, distance, desire to push the (mount) horse, pain manifestation, focus and concentration during the attack of the (mount) horse, trajectory of charge, lowering of head, repetition, type of lunge and strength. The total number of animals analyzed was 1720 (933 cows and 787 bulls). All information was collected and processed with the specific and purpose built software, DeLidia (v. 2.0.1505) in order to study and evaluate the behavior of the animals during tienta or lidia. The evaluations included consanguinity, sex, location, type of show, number of varas, lancer and bullfighter. Each instance was evaluated for phenotypic responses, hereditary traits, genetic correlations, and breeding values of sires used. The estimates of h2 were from low to moderate magnitude, between 0.06±0.03 and 0.36±0.026, corresponding to the behavioral units FZA and REP; the average of all units was 0.21±0.05. All rg values were positive excep those involved with FZA that were negative; the lowest positive value of rg was 0.1 for GEN and HUM, while the highest was 0.79 for FIJ and RDO. VG trends were positive and different from zero Doctorado
- Published
- 2016
39. Estimación de parámetros genéticos para producción de leche en búfalas (Bubalus bubalis) de segundo y tercer parto mediante modelos de regresión aleatoria
- Author
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Pineda Sierra, Sebastián, Agudelo Gómez, Divier Antonio, and Cerón Muñoz, Mario Fernando
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Heritability ,Genetic correlation ,Heredabilidad ,Correlacion genética ,Legendre polynomials ,Polinomios de Legendre - Abstract
Genetic parameters and covariance functions for test day (TD) of milk yield in buffaloes in Colombia by random regression models (MRA) with orthogonal Legendre polynomials (LP) were estimated. Records of 16738 and 14275 TD of 2284 and 1987 animals of second (L2) and third (L3) lactation were used, respectively. The average lactation curve of the population fixed effect and additive genetic and permanent environment random effect were estimated by MRA using third to sixth LP order and the residuals variances were modeled using homogeneous and heterogeneous structures. The best model was obtained with a third, fifth and fourth LP order for fixed curve of the population, genetic and permanent environment effects, respectively and fourth heterogeneous residual variances for L2 and L3 lactation. The estimated heritabilities varied between 0.05 and 0.24. The estimates of genetic correlations were highest between adjacent days. It is concluded that the application of MRA in L2 and L3 lactation described properly genetic parameters for milk yield in buffaloes. RESUMEN: Se estimaron los parámetros genéticos y las funciones de covarianzas para la producción de leche en el día de control (PDCL) en búfalas de Colombia, mediante análisis de regresión aleatoria con polinomios ortogonales de Legendre (LP). Se utilizaron registros de 16,738 y 14,275 PDCL de 2,284 y 1,987 animales de segunda (L2) y tercera (L3) lactancia, respectivamente. La media de la curva lactancia fija de la población y los efectos aleatorios ambiente genético y permanente aditivo se estimaron por MRA utilizando LP de tercer a sexto orden y varianzas residuales de estructuras homogéneas y heterogéneas. El mejor modelo se obtuvo por tercera, quinta y cuarta orden de LP para estimar la curva fija de la población, el efecto genético y de ambiente permanente, respectivamente, y cuarto varianzas residuales heterogéneos para las lactancias L2 y L3. Las heredabilidades estimadas variaron entre 0.05 y 0.24. Las estimaciones de las correlaciones genéticas fueron más altas entre los días adyacentes. Se concluye que la aplicación de los modelos de regresión aleatoria en L2 y L3 lactancia describen correctamente los parámetros genéticos para la producción de leche en los búfalos. COL0006779
- Published
- 2015
40. Ganancia genética esperada e interacción genotipo-ambiente en Acacia mangium en la zona norte de Costa Rica
- Author
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Benjamín Pavlotzky and Olman Murillo
- Subjects
ensayos genéticos ,lcsh:S ,costa rica ,lcsh:S1-972 ,provenances ,genetic correlation ,lcsh:Agriculture ,mejoramiento genético ,interacción genotipo-ambiente ,tree improvement ,genotype-environment interaction ,correlación genética ,lcsh:Agriculture (General) ,progeny test ,acacia mangium - Abstract
Two Acacia mangium Willd. progeny tests were evaluated, pursuing an increment in the profitability of commercial plantations. The 25 open-pollinated families were established in Los Chiles and San Carlos, northern region of Costa Rica, in year 2006, and evaluated in 2007 and in 2010. Genetic material came from plus tree selections obtained by GENFORES, a costarican tree-improvement and gene-conservation cooperative. In each trial, families were represented by 48 progenies, planted in 4 pairs randomly distributed within each of the 6 blocks. In 2010, DBH, survival rate, commercial number of logs per tree, forking, forking height and log quality in the first 4 logs, were evaluated. Based on these measurements, wood commercial volume per tree and per hectare were estimated. Data was analyzed with SELEGEN software from EMBRAPA, Brasil, in order to determine all genetic parameters of the breeding population. All traits evaluated showed family mean heritability values over 0.46. Genetic gain in commercial volume per hectare was estimated as 55.8%, when selecting as parents the 2 best individuals from the top 12 families, which would correspond to an expected commercial volume.ha -1 , at 4 years age, of 78.93 m 3 .ha -1 (around 20 m 3 .ha -1 .year -1 ). The 2 Colombian provenances were significantly superior in growth to the rest of the evaluated materials. No significant gene-environment interaction was observed between both sites. Genetic correlations among evaluated traits showed that diameter growth rate is expressed early in this tree species, thus could be used in shortening future selections. Se evaluaron 2 ensayos de progenie de Acacia mangium Willd., con el objetivo de con- tribuir a aumentar su rentabilidad en plantaciones comerciales. Las 25 familias de polinización abierta fueron establecidas en el 2006 en los cantones de Los Chiles y San Carlos, zona norte de Costa Rica, y evaluados en 2007 y 2010. El material genético provino de selecciones de árbo- les plus realizadas por GENFORES, cooperativa costarricense de conservación y mejoramiento genético forestal. Cada accesión estuvo represen- tada por 48 progenies, divididas en 4 parejas de individuos, aleatoriamente distribuidas dentro de cada uno de 6 bloques del ensayo. En la medición del 2010 se evaluó el DAP, tasa de sobrevivencia, número de piezas comerciales por árbol, presen- cia de bifurcación, altura de bifurcación y cali- dad de las primeras 4 trozas. Con base en estas mediciones, se estimó el volumen comercial por árbol y por hectárea. Los datos fueron analizados mediante el software especializado SELEGEN de EMBRAPA, Brasil, con el fin de determinar todos los parámetros genéticos de la población de mejoramiento. Todos los caracteres evaluados exhibieron valores de heredabilidad familiar media superior a h 2fM >0,46. La ganancia genética estimada en volumen comercial por hectárea fue de 55,8%, si se selecciona como progenitores los 2 mejores individuos dentro de las mejores 12 familias del ranking, lo que corresponde a una producción en volumen comercial de 78,93 m 3 .ha -1 a los 4 años (aproximadamente 20 m 3 .ha -1 .año -1 ). Las 2 procedencias colombianas exhibieron un crecimiento significativamente superior a todo el resto de materiales evaluados. No se observó interacción genotipo-ambiente significativa entre ambos sitios. Las correlaciones genéticas entre los caracteres evaluados mostraron que la tasa de crecimiento del DAP se expresa tempranamente en esta especie, y por tanto, podría ser utilizada en una reducción a futuro del proceso de selección.
- Published
- 2014
41. Parámetros Genéticos del Crecimiento Temprano de Familias de Medios Hermanos de Pinus Pseudostrobus Lindl. En Michoacán, México
- Author
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Sánchez Vargas, Nahum, Cambrón Sandoval, Victor, Sáenz Romero, Cuauhtemoc, and Vargas Hernández, Jesús
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Early selection ,Genetic correlation ,Revistas ,Geografía ,Correlación edad-edad ,Facultad de Ciencias Forestales y Ambientales ,Selección temprana ,Artículos [Revista Forestal Venezolana] ,Correlación genética ,Heritability ,Heredabilidad ,Medio Ambiente ,Age-age correlation ,Revista Forestal Venezolana - Abstract
Pinus pseudostrobus es una de las principales especies forestales de México y particularmente de Michoacán. El tiempo es un factor importante en el mejoramiento genético, por lo que frecuentemente se hacen evaluaciones tempranas que permiten seleccionar las mejores familias que serán establecidas en campo. El objetivo de este trabajo fue evaluar los parámetros genéticos del crecimiento inicial de 15 familias de medios hermanos de P. pseudostrobus a través del tiempo. Se midió la altura y diámetro en un ensayo de progenies de medios hermanos, con un diseño de bloques completos al azar a los dos, cuatro y seis meses de edad y se relacionaron con el número de yemas aciculares, longitud de cotiledón (CL), largo, ancho y grueso de semilla. La heredabilidad individual para altura fue más elevada (h2i = 0,70) que para diámetro (h2i = 0,26), mientras que a nivel de medias de familia la heredabilidad fue similar para estas características (h2f = 0,96 y h2f = 0,87, respectivamente); LCN y altura mostraron la mayor correlación genética (rg = 0,59); las correlaciones genéticas edad-edad se reducen más rápidamente al aumentar la diferencia de edades para altura que para diámetro de planta. Los resultados evidencian posibilidades de selección temprana con base en la altura y de selección a través del tiempo con base en el diámetro. 65-76 Semestral
- Published
- 2014
42. Correlaciones genotípicas, fenotípicas y ambientales, y análisis de sendero en tomate de árbol (Cyphomandra betacea Cav. Sendt.)
- Author
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Lagos Santander, Liz Katherine, Vallejo, Franco Alirio, Lagos Burbano, Tulio César, and Duarte Alvarado, David Esteban
- Subjects
phenotypic correlation ,Cyphomandra betacea ,Análisis de sendero ,path analysis ,correlación genética ,genetic correlation ,correlación fenotípica ,correlación ambiental ,environmental correlation - Abstract
En el estudio se evaluaron diferentes componentes de producción y se estimaron las correlaciones fenotípicas, genéticas y ambientales, considerando nueve variables relacionadas con el tamaño y la calidad del fruto de tomate de árbol (Cyphomandra betacea Cav. Sendt.); igualmente se establecieron los efectos directos e indirectos de las variables componentes de calidad sobre el peso del fruto. Para el efecto se utilizaron los datos existentes de 81 híbridos (72 híbridos interpoblacionales y nueve testigos) dispuestos en tres repeticiones, en condiciones del departamento de Nariño, Colombia. Los resultados obtenidos indicaron que las correlaciones genotípicas fueron superiores a las fenotípicas y ambientales. El peso de fruto (PF) presentó las mayores correlaciones genéticas con el peso de semilla por fruto (rG = 0.97) y con el peso de pulpa más semilla (rG = 0.92). El análisis de sendero con base en correlaciones genotípicas mostró que el peso de pulpa más semilla fue la variable que tuvo el mayor efecto directo sobre el PF (1.353). Esto demuestra que una selección por peso de fruto da como resultado un aumento en peso de pulpa más semilla. Teniendo en cuenta las correlaciones fenotípicas, este análisis permitió establecer que los efectos directos de peso de semilla de fruto (PSF) y peso de pulpa más semilla (P + S) (1.166 y 0.743, respectivamente) son los que más contribuyen al PF. The study different production components were evaluated and phenotypic, genetic and environmental correlations were estimated, considering nine characters related to the size and quality of tomato tree fruit (Cyphomandra betacea Cav Sendt.), also settled the direct and indirect effects of the component variables of quality on fruit weight. To effect the existing data of 81 hybrids (72 interpopulation hybrids and nine witnesses) arranged in three replications, under the Department of Nariño, Colombia were used. The results indicated that genotypic correlations were higher than phenotypic and environmental. The fruit weight (PF) presented the highest genetic correlations with seed weight per fruit (rG = 0.97) and with more seed pulp weight ( rG = 0.92 ) . Path analysis based on genotypic correlations showed that more seed pulp weight was the variable that had the most direct effect on the PF (1.353). This shows that a selection of the fruit weight results in an increase in weight of pulp more seed. Given the phenotypic correlations, this analysis established that the direct effects of seed weight of fruit (PSF) and more seed pulp weight (P + S ) (1.166 and 0.743 , respectively ) are the largest contributors to PF.
- Published
- 2013
43. Importancia de la interacción genotipo x ambiente en rasgos de producción en ganado lechero
- Author
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Nicacia Hernández-Hernández, Gaspar Manuel Parra-Bracamonte, Juan Carlos Martínez-González, and Eugenia Guadalupe Cienfuegos-Rivas
- Subjects
0301 basic medicine ,SciELO ,business.industry ,Correlación genética ,0402 animal and dairy science ,04 agricultural and veterinary sciences ,General Medicine ,Biology ,040201 dairy & animal science ,Genetic correlation ,Biotechnology ,03 medical and health sciences ,030104 developmental biology ,Genetic resources ,Multidisciplinarias (Ciencias Sociales) ,ganado lechero ,Genotype ,Production (economics) ,business ,Dairy cattle ,Selection (genetic algorithm) - Abstract
El ganado bovino lechero expresa con diferente nivel de eficiencia su potencial genético dependiendo de la región en que se desarrolla; a este efecto se le denomina interacción genotipo x ambiente (IGA), y puede afectar la eficiencia de los programas de mejoramiento genético. Este fenómeno debe ser considerado al importar recursos genéticos de otros países e incluso de otras regiones dentro de un mismo país. El objetivo de este trabajo fue analizar los principales aspectos de la IGA en el mejoramiento genético de ganado bovino lechero. Los programas de mejoramiento genético deben estar basados en el registro de las operaciones que se realizan en cada una de las unidades de operación, lo que permitirá establecer cuales fueron los principales factores que influyeron en la expresión del potencial genético y su reflejo en la producción alcanzada. Se concluye que la selección de los sementales de la próxima generación deberá realizarse en las mismas condiciones donde se usarán sus progenies, buscando minimizar la IGA. Archivo XML (SciELO)
- Published
- 2016
44. Parámetros genéticos en características de crecimiento y densidad de la madera en progenies de Eucalyptus grandis
- Author
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Harrand, Leonel
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Early selection ,Genetic correlation ,Pilodyn ,Correlación edad-edad ,Selección temprana ,Correlación genética ,Genetic stability ,Response to selection ,Respuesta a la selección ,Heritability ,Maestría ,Heredabilidad ,Age-age correlation ,Estabilidad genética ,Selección indirecta ,Forestal ,Indirect selection ,Densidad de la madera ,Wood density - Abstract
Con el fin de determinar la estructura genética de las características de crecimiento y densidad de la madera (evaluada de manera directa y a través de la penetración del Pilodyn) y estimar la respuesta esperada a la selección masal en una población de Eucalyptus grandis formada por familias del NE de Queensland (Australia), se evaluó un ensayo de progenies a los 4.5 y 8.5 años de edad, establecido en tres sitios del NE argentino. Aunque se encontró una amplia variabilidad genética en todas las características evaluadas, las características de crecimiento [diámetro (DAP), altura (HT) y volumen (VOL)] mostraron diferente estructura y grado de control genético con respecto a las otras características [rectitud de fuste (FORM), proporción de corteza (COR) y penetración de Pilodyn (PILO)]; el efecto de orígenes fue importante en estas últimas y despreciable en las primeras; además, la heredabilidad individual de las características de crecimiento (0.11 – 0.16) fue menor que la de las otras características (0.20 – 0.35). Las correlaciones genéticas entre sitios fueron suficientemente altas (rgB >0.6) en todas las características como para considerar que la interacción genotipo-ambiente no afectaría al programa de selección. Las correlaciones genéticas entre las características de crecimiento fueron altas (rg>0.8), y prácticamente nulas entre éstas y FORM. PILO solo tuvo correlaciones moderadas con HT y COR. Las correlaciones edad-edad en las características de crecimiento y FORM fueron muy altas (rg>0.9). FORM, VOL y PILO a los 8.5 años de edad presentaron las mayores respuestas relativas a la selección, con valores de 8.74, 7.81 y 5.09%, respectivamente. DAP fue más eficiente (97%) que HT (90%) para aumentar el volumen por selección indirecta. La selección temprana (a los 4.5 años) para las características de crecimiento y rectitud de fuste presentó una eficiencia relativa por año superior al 155% con respecto a la selección directa a los 8.5 años de edad. Dado que PILO mostró un control genético más elevado (h2 = 0.33) que la densidad de la madera (h2 = 0.22) y una alta correlación genética con ésta (rg = -0.86) la selección indirecta por medio del Pilodyn puede ser tan eficiente como la selección directa pero con un ahorro del 95% del costo. Los resultados señalan que es posible llevar a cabo un programa de mejora genética manejando las características evaluadas de manera independiente o combinada, sin impactar de manera significativa sobre las demás, y utilizar selección temprana para las características de crecimiento y forma del tronco con un ahorro importante de tiempo y dinero.______With the purpose of determining the genetic structure of growth traits and wood density (evaluated directly and through Pilodyn penetration) and to estimate the expected response to masal selection in a Eucalyptus grandis population formed by families from NE Queensland, Australia, a progeny test established in three sites in NE Argentina was evaluated at 4.5 and 8.5 years of age. Although a broad genetic variability was found in all traits assessed, growth traits [diameter (DBH), height (HT) and volume (VOL)] showed different genetic structure and degree of genetic control with respect to the other traits [stem straightness (FORM), bark proportion (COR) and Pilodyn penetration (PILO)]. The origin effect was important in the latter traits and negligible in the former. Also, individual heritability of growth traits (0.11-0.16) was lower than that of the other traits (0.20-0.35). Genetic correlations between sites for all traits were high enough (rgB >0.6) to indicate that genotype-environment interaction would not affect the selection program. Genetic correlations between growth traits were high (rg>0.8), and negligible between these and FORM. PILO correlated only moderately with HT and COR. Age-age correlations for growth traits and FORM were very high (rg>0.9). FORM, VOL and PILO at 8.5 years-old presented the highest relative responses to selection, with 8.74, 7.81 and 5.09%, respectively. DAP is more efficient (97%) than HT (90%) to increase volume by indirect selection. Early selection (at age 4.5 years) for growth traits and stem straightness presented a relative efficiency per year superior to 155% with regard to direct selection at 8.5 years. Since PILO showed a higher genetic control (h2 = 0.33) that wood density (h2 = 0.22) and a high genetic correlation with it (rg = -0.86), indirect selection using the Pilodyn can be as efficient as direct selection but saving 95% of the cost. Results suggest that it is possible to conduct a genetic improvement program using the traits evaluated, independently or combined, without impacting in a significant way on the others, and to use early selection for growth traits and stem straightness with important savings in time and money.
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- 2012
45. Modelación de parametros genéticos mediante regresión aleatoria en búfalos lecheros
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July Gómez, Humberto Tonhati, V. Elmer Tapia, V. Donicer Montes, Júnior Sousa, and Naudin Hurtado-Lugo
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Ambiente ,Polynomial ,modelo animal ,animal model ,lcsh:S ,Ice calving ,General Medicine ,Residual ,genetic correlation ,Crossbreed ,lcsh:S1-972 ,lcsh:Agriculture ,Statistics ,Herd ,Additive genetic effects ,correlación genética ,lcsh:Animal culture ,Akaike information criterion ,lcsh:Agriculture (General) ,environment ,Dairy cattle ,Mathematics ,lcsh:SF1-1100 - Abstract
Los modelos de regresión aleatoria (MRA) son utilizados para estudiar las curvas de lactancia individuales como desvíos de la media, mediante el uso de polinomios ordinarios de funciones lineales. Fueron analizados 5.386 registros para La PDC de 1.546 primeras lactancias de búfalas mestizas, hijas de 30 toros y 446 búfalas, entre 1998 y 2005. Los componentes de varianza fueron estimados utilizando el paquete estadístico WOMBAT. El modelo incluyó como aleatorios los efectos genéticos aditivo y de ambiente permanente, como efectos fijos los grupos contemporáneos (mes y año del control) y edad de la búfala al parto (efecto lineal y cuadrático). Las varianzas residuales fueron modeladas utilizando clases de varianza con 4 clases residuales. Los resultados de los criterios de información de Akaike y de Bayesiano de Schwarz, sugirieron que el modelo que considero el 7 orden del polinomio de Legendre para el efecto aditivo y el 6 orden polinomial para el efecto de ambiente permanente fue el mejor. Las heredabilidades variaron desde 0,10 hasta 0,33 a lo largo de la lactancia. En conclusión, los MRA son apropiados para estudiar la curva de lactancia en búfalos lecheros en este rebaño.
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- 2012
46. Ganancia genética esperada en Acacia mangium en Los Chiles, zona norte de Costa Rica
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Benjamín Pavlotzky-Blank and Olman Murillo-Gamboa
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education.field_of_study ,biology ,Population ,correlación genética ,lcsh:S ,Soil Science ,progenie ,Forestry ,Heritability ,biology.organism_classification ,Genetic correlation ,lcsh:Agriculture ,Mejoramiento genético ,procedencias ,Genetic gain ,Acacia mangium ,education ,Agronomy and Crop Science ,Hectare ,Tree species ,Selection (genetic algorithm) ,Food Science - Abstract
Ganancia genética esperada en Acacia mangium en Los Chiles, zona norte de Costa Rica. Con el objetivo de seleccionar los materiales de mayor crecimiento y calidad de fuste en Acacia mangium, se evaluó un ensayo de progenie de Acacia mangium Willd. conformado por veinticinco familias.El ensayo fue establecido en Los Chiles, zona norte de CostaRica, en 2006 con evaluaciones en el 2007 y en 2010. Se utilizó material genético seleccionado por la Cooperativa de Conservación y Mejoramiento Genético Forestal “GENFORES”,en Costa Rica y Colombia. Cada familia estuvo representada por 48 progenies, plantadas en cuatro parejas distribuidas enforma aleatoria dentro de cada uno de los seis bloques delensayo. Se evaluó el diámetro a la altura de pecho “DAP”,incremento en DAP, adaptabilidad al sitio, número de trozas comerciales, bifurcación, altura de bifurcación, calidad de las primeras cuatro trozas. Se determinó el volumen de maderacomercial por árbol y hectárea. Los datos fueron analizadospor medio del software SELEGEN de EMBRAPA para obtenerlos parámetros genéticos. Todos los caracteres registraron valores de heredabilidad media familiar superiores a 0,68.Si se seleccionaran los dos mejores individuos dentro de las mejores doce familias, se obtendría una ganancia genética del40,8% en volumen comercial/ha a los cuatro años de edad.Esta ganancia corresponde a un volumen comercial de 91,65m3/ha, a una tasa de 22,9 m3/ha/año. Las dos procedencias derivadas de Colombia son significativamente superiores a los demás materiales evaluados. El análisis de correlación genética entre caracteres muestra que la tasa de crecimiento diamétrico se expresa desde temprana edad en esta especie, lo que podría ser utilizado a futuro en una selección a menor edad.
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- 2012
47. Alternativas de mejora de Pinus pinaster Ait. en la zona interior de Galicia
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Mata Pombo, Raúl de la, Zas Arregui, Rafael, and Merlo Sánchez, Esther
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Genetic correlation ,Resistencia a la sequía ,Plasticidad fenotípica ,Matriz de varianzas-covarianzas ,REML estimation ,Adaptación ambiental ,Área de mejora ,Breeding areas ,Interacción con cambios de ranking ,Pinus pinaster ,Phenotypic plasticity ,Progeny trial ,Programa de mejora ,Ensayo de procedencias ,Híbridos interprocedencia ,2417.14 Genética Vegetal ,Estimación REML ,Ensayo de progenies ,Biomass allocation ,Modelos mixtos ,Genotype × environment interaction ,Seed origin ,Climate change ,Cambio climático ,Mixed models ,Genetic resources ,Interacción genotipo × ambiente ,Provenance trial ,Interprovenance hybrids ,Spatial analysis ,Correlación genética ,Análisis espacial ,Drought resistance ,Breeding program ,Environmental adaptation ,Variance-covariance matrix ,Crossover interaction ,2409.03 Genética de Poblaciones ,Estabilidad ambiental ,Recursos genéticos ,Fuente semillera ,Environmental stability ,Distribución de biomasa - Abstract
298 p., [EN] Maritime pine (Pinus pinaster Ait.) occurs naturally in a wide variety of sites around SW Europe, from typical Mediterranean climates to areas in Northern Spain and France with a strong Atlantic influence. Within its distribution range populations are strongly differentiated, showing strong adaptations to local environmental conditions. Both climates encounter each other in Galicia, where two bioclimatic regions can be differentiated: coastal and inland. The inland region is a boundary area where the Atlantic climate of the coastal region meets with the typical Mediterranean climate of Central Spain. Compared to the Atlantic coast, climate in this area has a pronounced summer drought, lower annual precipitation, and higher annual thermal oscillation. Despite the high productivity and ecological importance of maritime pine in inland Galicia, local forest reproductive material (FRM) of high genetic quality is not available for this area. Seed sources originating elsewhere and of unknown adaptation to this area are commonly used for reforestation. Looking for alternative material that performs well in the inland region has become a primary objective in order to provide immediate seed sources suitable for planting in this area., As a first approximation, we analyzed the performance of six Mediterranean provenances in three sites in the interior of Galicia seven year after planting. Provenances coming from the mildest climates grew faster but showed inferior stem form. The provenance ´ site interaction was weak, although some significant provenance rank changes were observed in the driest site. Among the tested provenances, Serranía de Cuenca showed good growth in all sites and acceptable stem form, being thus a potential recommended material for using in the area. The Albarracín origin also showed good results, with excellent stem form and acceptable growth, especially in the driest site. A combined spatial analysis allowed us to compare the tested provenances with improved materials from Coastal Galicia (GC) and Western Australia (WA) breeding programs planted in adjacent progeny trials. Although the differences were small, the Atlantic material of both breeding programs performed slightly better than the Mediterranean provenances, and represents a recommended alternative material for use in reforestation in this transitional climate region., Based on the good performance of the coastal material in the inland region, and with the aim of exploiting the genetic gains of both breeding programmes, we analyzedthe performance in field conditions of improved families of the GC and WA breeding programmes. Growth, stem characteristics and branch habit were evaluated in five progeny trials established following a coastal-to-inland gradient. Likelihood-based analyses were used to estimate genetic correlations between environments and to test statistically for causes and patterns of genotype ´ environment interaction. The results indicated that there is not sufficient evidence to subdivide Galicia into the two current deployment areas. Interaction patterns do not reveal significant differences between zones, and crossover interactions for height growth appeared both between and within areas. On the inland sites, the Atlantic improved materials clearly outperformed unimproved seedlots tested in adjacent provenance trials, suggesting the feasibility of using both the CG and WA breeding materials as sources of FRM for reforestation in inland Galicia. Of the two, the WA material showed excellent results for all traits. The inclusion of this material into the Galician maritime pine breeding population should be strongly considered., Based on the results above, and aiming to better understand the interaction patterns we integrated the whole collection of genetic trials of the GC breeding program. We analyse then plasticity patterns across regions in the GC breeding population to assess the suitability of current breeding areas and how genetic material will likely respond to future climate. Total height three and eight years after plantation was assessed in 16 trials established along the coast and in inner Galicia. Clustering of environments with similar genotypic performance, family sensitivities to climatic factors and stability analyses were performed. Sizeable genetic variation in plasticity was found among families, and crossover genotype × environment interactions were detected within and between regions. Therefore, it was unfeasible to regionalize Galicia into alternative areas of stable genotypic performance. Only the cold regime was found to noticeably underlie the array of phenotypic responses to changing environmental conditions. Results suggest that previous delimitation in two breeding areas is pointless, and indicate reduced effects of a changing climate towards Mediterranean conditions on decreasing population fitness., As a final line of research, we assessed the drought response under controlled conditions of different origins of the species and their synthetic hybrids. The analysis of phenotypic plasticity of growth and biomass allocation traits allowed us distinguishing common and divergent patterns between populations. In general, plants under stress, rather than redirect their resources towards suitable structures to deal with drought suchroots, they could be showing a conservative strategy by reducing their growth investment and delaying the ontogenic progress. Besides, biomass allocation was under strong genetic control following a clear geographic pattern with population divergence that segregated populations into two main groups: i) Atlantic populations that showed increased investment in growth structures, and ii) Mediterranean populations that showed water stress tolerance strategies prioritizing root investment and a more conservative resource allocation pattern. Dominance of the mediterranean-like behaviour was also detected in the tested hybrids, since populations were grouped within the Mediterranean group whenever one of its parents had this origin. Neither of the hybrids showed a height growth higher than the GC breeding population, and only Soria-Burgos × Carballiño population had proper growth while maintaining a pattern of biomass allocation more adapted to drought, which may indicate its suitability for use in inland Galicia., [ES] El pino marítimo (Pinus pinaster Ait.) se distribuye por una amplia variedad de ambientes en el SO de Europa, desde los típicos climas Mediterráneos hasta áreas en Francia y en el Norte de España con marcada influencia oceánica. Dentro de su área de distribución natural las poblaciones aparecen altamente diferenciadas, mostrando adaptaciones locales a las condiciones ambientales. Ambos climas se encuentran en Galicia, donde se pueden distinguir dos regiones bioclimáticas: la costera y la interior. La región interior es un área fronteriza donde el clima Atlántico de la costa se encuentra con el típico clima Mediterráneo de España Central. En comparación con la costa Atlántica, el clima en esta área tiene una pronunciada sequía estival, baja precipitación anual, y más alta oscilación térmica. A pesar de la alta productividad y la importancia ecológica del Pino marítimo en el interior de Galicia, no existe material forestal de reproducción (MFR) de calidad para esta región, y frecuentemente se utiliza material de otros orígenes con dudosa adaptación. La búsqueda de material alternativo con buen comportamiento en la región interior se ha convertido en un objetivo fundamental con el fin de proporcionar de manera inmediata fuentes de semilla aptas para la plantación en esta área., Como primera aproximación, se analizó el comportamiento de seis procedencias Mediterráneas en tres sitios del interior de Galicia siete años después de la plantación. Las procedencias de los climas más suaves crecieron más rápido pero mostraron formas del fuste de peor calidad. La interacción procedencia × sitio fue débil, aunque se observaron cambios de ranking significativos en el sitio más seco. De entre las procedencias ensayadas, Serranía de Cuenca mostró buen crecimiento y forma del fuste aceptable en todos los sitios, siendo un material recomendado para ser usado en la región. El origen de Albarracín mostró también buenos resultados, con excelentes formas del fuste y crecimiento aceptable, especialmente en el sitio más seco. El análisis espacial combinado nos permitió comparar las procedencias ensayadas con materiales de los programas de mejora de Galicia-Costa (GC) y Australia Occidental (WA) plantados en los ensayos de progenie adyacentes. Aunque las diferencias fueron pequeñas, el material Atlántico de ambos programas se comportó ligeramente mejor que las procedencias Mediterráneas, suponiendo un material alternativo recomendado para su uso en repoblaciones en esta región climática de transición., En base al buen comportamiento del material costero en la región interior, y con el objetivo de aprovechar la ganancia genética de los programas de mejora de GC y WA, se analizó el comportamiento en condiciones de campo de distintas familias de ambos programas. Se evaluó el crecimiento, la calidad del fuste y la ramosidad en cinco ensayos de progenie instalados siguiendo un gradiente costa-interior. Se usaron análisis basados en la verosimilitud para estimar las correlaciones genéticas entre ambientes y para probar estadísticamente las causas y patrones de la interacción genotipo × ambiente. Los resultados indican que no existen suficientes evidencias para subdividir Galicia en las dos actuales áreas de mejora. Los patrones de interacción no revelan diferencias significativas entre zonas, y existen interacciones con cambios de ranking tanto entre como dentro de ellas. En los sitios del interior, los materiales mejorados Atlánticos superaron claramente a los lotes no mejorados probados en los ensayos de procedencias adyacentes, sugiriendo la posibilidad de usar los materiales mejorados tanto de GC como de WA como fuentes de MFR para repoblación en el interior de Galicia. De los dos, el material de WA mostró excelentes resultados para todos los caracteres por lo que debe considerarse la inclusión de este material en el programa de mejora de P. pinaster para Galicia., En base a los resultados anteriores, nos planteamos integrar la información de la colección completa de ensayos genéticos pertenecientes al programa de mejora de GC. Analizamos entonces los patrones de plasticidad a través de regiones en la población de mejora del programa para evaluar la idoneidad de las actuales áreas de mejora e indagar sobre la respuesta de este material al cambio climático. Se evaluó la altura total tres y ocho años después de la plantación en 16 ensayos establecidos tanto en la costa como en el interior de Galicia. Se analizó la agrupación de ambientes con similar comportamiento genotípico, la sensibilidad del material a los factores climáticos y la estabilidad familiar. Se encontró una considerable variación de la plasticidad entre familias, y se detectaron interacciones genotipo × ambiente dentro y entre regiones. No fue posible una regionalización alternativa de Galicia en áreas de comportamiento genotípico estable. Se encontró además que el régimen de frío fue el principal factor que moduló las respuestas fenotípicas a la variación de las condiciones ambientales. Los resultados sugieren que la delimitación previa en dos áreas de mejora no está fundamentada, y sugieren un escaso efecto del cambio climático hacia condiciones más Mediterráneas en el éxito biológico de la población., Como última línea de trabajo, se evaluó la respuesta a la sequía bajo condiciones controladas de diferentes orígenes de la especie y sus híbridos, seleccionados en un gradiente de Mediterraneidad moderada. El análisis de la plasticidad fenotípica de las variables de crecimiento y de distribución de biomasa nos permitió distinguir ciertos patrones adaptativos comunes y otros divergentes entre poblaciones. De manera general, las plantas sometidas a estrés, más que redirigir sus recursos fotosintéticos hacia las estructuras adecuadas para afrontar la sequía, podrían estar mostrando una estrategia conservadora reduciendo su inversión en crecimiento y retrasando el desarrollo ontogénico. Además el reparto de la biomasa estuvo sometido a fuerte control genético en base a un patrón geográfico con divergencia poblacional que segrego a las poblaciones en dos grupos principales: i) poblaciones de carácter Atlántico que mostraron mayor inversión en estructuras de crecimiento, y ii) poblaciones de carácter Mediterráneo que mostraron estrategias de resistencia al estrés hídrico priorizando la inversión en raíces y una distribución de recursos más conservadora. Se detecto además dominancia en el comportamiento de tipo Mediterráneo en los híbridos ensayados, ya que las poblaciones pertenecieron al grupo Mediterráneo en cuanto uno de sus parentales tuvo este origen. Ninguno de los híbridos mostró un crecimiento en altura superior al de la población de mejora de Galicia-Costa, y únicamente la población Soria-Burgos × Carballino tuvo un crecimiento adecuado mientras que mantuvo un patrón de distribución de biomasa más adaptado a la sequía, lo que podría indicar su adecuación para su uso en la zona interior de Galicia., Esta tesis ha sido financiada con proyectos concedidos por el Ministerio de Ciencia e Innovación (INIA RTA07-100-00, INIA RTA05-173 y AGL2010-18724,) y la Xunta de Galicia. (PGIDIT02PXIC50201P). Raúl de la Mata Pombo ha estado financiado por dos becas de la Xunta de Galicia para la formación en tareas investigadoras en el Centro de Investigaciones Forestales de Lourizán (Xunta de Galicia).
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- 2012
48. Parámetros genéticos de las características andrológicas en la especie bovina
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Silva, MR, Pedrosa, VB, Silva, JBC, Herrera, LGG, Eler, JP, and Albuquerque, LG
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cattle ,bovinos ,examen andrológico ,correlación genética ,heritability ,genetic correlation ,breeding soundness ,heredabilidad - Abstract
La precocidad sexual y fertilidad tienen gran impacto en el éxito económico de los rebaños bovinos comerciales, en que las características reproductivas han sido adoptadas como criterios de selección. Sin embargo, la mayoría de estas características dependen de eventos reproductivos de las hembras y, con excepción del perímetro escrotal, pocos estudios abordan las características andrológicas. Las estimaciones de las heredabilidades y correlaciones genéticas de las características testiculares y seminales, además del comportamiento sexual, podrán proveer alternativas para la elaboración de estrategias más adecuadas de selección para fertilidad, en conjunto con las demás características de interés económico. The sexual precocity and fertility of bovines have great impact on the economic success of commercial cattle herds, where some reproductive traits have been adopted as selection criteria. However, the majority of these traits depend on reproductive events of the females and, with exception of the scrotal circumference, few studies approach others andrological traits. The estimation of heritabilities and genetic correlations of testicular and seminal traits and also sexual behaviour, will allow to provide alternatives for the design of more appropriate selection strategies for fertility, together with other economic traits.
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- 2012
49. Índices de selección para producción de maíz forrajero
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Tucuch-Cauich, Carlos Alejandro, Rodríguez-Herrera, Sergio Alfredo, Reyes-Valdés, Manuel Humberto, Pat-Fernández, Juan Manuel, Tucuch-Cauich, Fulgencio Martín, and Córdova-Orellana, Hugo Salvador
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Genetic correlation ,phenotypic correlation ,forage production ,Correlación genética ,producción forrajera ,genetic variance and relative efficiency ,correlación fenotípica ,varianza genética y eficiencia relativa - Abstract
The objective of this research was to estimate selection indexes of agronomic traits that help in selecting the genetic material used in the production of forage, and evaluate the relative efficiency of the indexes estimated. We evaluated 28 direct crosses (Griffing’s method IV), the product of diallel crosses design with eight lines of high quality protein maize (QPM).The study was done in the Rancho Ampuero in Torreon, Coahuila, Me xico, in 2003 and 2004. The experimental designwas a randomized complete block with two repe titions, the variables evaluated were: plant height (PH), ear height(AM ), green forage yield (RFV) and dry forage yie ld (RFS).It was found: a) greater efficiency by combining characters correlated with the trait of interest, b) the correlation between characters per se, causes decreases in the efficiency of the index, c) the theoretical response to the selection was greaterwhen using selection indices than when done solely on forage yield, d) the most efficient selection indices took into account the yie ld of green fodder and those varia bles with the highestgenetic correlation (AP and AM ), e) the index selected included the variables plant height, ear height and forage yield(I=-20,88 X1 +49,26 X2 -0,11 X3) with a relative efficiency of 1,5 7%. El objetivo del presente trabajo fue estimar índices de selección de caracteres agronómicos que ayuden a seleccionar los materia les genéticos que se utilizan en la producción de forraje y evaluar la eficiencia relativa de los índices estimados.Se evaluaron 28 cruzas directas (método IV de Griffing),producto de un diseño de cruzas dialélicas, con ocholíneas de maíz de alta calidad proteínica (QPM), en el Rancho Ampuero en Torreón, Coahuila, México, en el año 2003 y 2004. El diseño experimental utilizado fue bloques completos al azar con dos repeticiones, las variables evaluadas fueron:altura de planta (AP), altura de mazorca (AM ), rendimie ntode forraje verde (RFV) y rendimiento de forraje seco (RFS).Se encontró que: a) se obtuvo mayor eficiencia al combinar caracteres correlacionados con el carácter de interés, b) la correlación entre caracteres per se, causó decrementos en laeficiencia del índice, c) la respuesta teórica a la selección,al usar índices, fue mayor que la basada solamente en rendimiento de forraje verde, d) los índices de selección más eficientes fueron los que tomaron en cuenta el rendimiento de forraje verde y aquellas varia bles con más alta correlación genética (AP y AM ), e) el índice seleccionado fue el que incluyó las variables altura de planta, altura de mazorca yrendimiento de forraje verde (I=-20,88 X1 +49,26 X2 -0,11X3) con una eficiencia relativa de 1,5 7%.
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- 2011
50. ÍNDICES DE SELECCIÓN PARA PRODUCCIÓN DE MAÍZ FORRAJERO
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Hugo Córdova-Orellana, Juan Manuel Pat-Fernández, Carlos Alejandro Tucuch-Cauich, Manuel Humberto Reyes-Valdés, Sergio Alfredo Rodríguez-Herrera, and Fulgencio Martín Tucuch-Cauich
- Subjects
Genetic correlation ,phenotypic correlation ,varianza genética y eficiencia relativa ,Crop yield ,forage production ,genetic variance and relative efficiency ,lcsh:S ,Correlación genética ,Soil Science ,Forage ,producción forrajera ,lcsh:Agriculture ,Diallel cross ,Animal science ,Efficiency ,Fodder ,Agrociencias ,Agronomy and Crop Science ,Selection (genetic algorithm) ,correlación fenotípica ,Food Science ,Mathematics - Abstract
Índices de selección para producción de maíz forrajero. El objetivo del presente trabajo fue estimar índices de selección de caracteres agronómicos que ayuden a seleccionar los materia les genéticos que se utilizan en la producción de forraje y evaluar la eficiencia relativa de los índices estimados. Se evaluaron 28 cruzas directas (método IV de Griffing), producto de un diseño de cruzas dialélicas, con ocho líneas de maíz de alta calidad proteínica (QPM), en el Rancho Ampuero en Torreón, Coahuila, México, en el año 2003 y 2004. El diseño experimental utilizado fue bloques completos al azar con dos repeticiones, las variables evaluadas fueron: altura de planta (AP), altura de mazorca (AM), rendimiento de forraje verde (RFV) y rendimiento de forraje seco (RFS). Se encontró que: a) se obtuvo mayor eficiencia al combinar caracteres correlacionados con el carácter de interés, b) la correlación entre caracteres per se, causó decrementos en la eficiencia del índice, c) la respuesta teórica a la selección, al usar índices, fue mayor que la basada solamente en rendimiento de forraje verde, d) los índices de selección más eficientes fueron los que tomaron en cuenta el rendimiento de forraje verde y aquellas variables con más alta correlación genética (AP y AM), e) el índice seleccionado fue el que incluyó las variables altura de planta, altura de mazorca y rendimiento de forraje verde (I=-20,88 X1 +49,26 X2 -0,11 X3) con una eficiencia relativa de 1,5 7%. Selection indexes for yield forage maize. The objective of this research was to estimate selection indexes of agronomic traits that help in selecting the genetic material used in the production of forage, and evaluate the relative efficiency of the indexes estimated. We evaluated 28 direct crosses (Griffing’s method IV), the product of diallel crosses design with eight lines of high quality protein maize (QPM). The study was done in the Rancho Ampuero in Torreon, Coahuila, Mexico, in 2003 and 2004. The experimental design was a randomized complete block with two repetitions, the variables evaluated were: plant height (PH), ear height (AM), green forage yield (RFV) and dry forage yield (RFS). It was found: a) greater efficiency by combining characters correlated with the trait of interest, b) the correlation between characters per se, causes decreases in the efficiency of the index, c) the theoretical response to the selection was greater when using selection indices than when done solely on forage yield, d) the most efficient selection indices took into account the yield of green fodder and those variables with the highest genetic correlation (AP and AM ), e) the index selected included the variables plant height, ear height and forage yield (I=-20,88 X1 +49,26 X2 -0,11 X3) with a relative efficiency of 1,5 7%.
- Published
- 2011
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