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Background: Buffalo breeding has significantly increased in Brazil over recent years. However, few genetic evaluations have been conducted. Objective: To assess Genotype x Environment Interactions in the Mediterranean Water Buffalo in Brazil, for weight at 205 days of age, using reaction norm models via random regression. Methods: Data for buffaloes born between 1990 and 2014 were collected from five farms ascribed to the Brazilian Buffaloe Improvement Program, located in the North (1), Northeast (1), South (2) and Southeast (1) regions of Brazil. The initial database consisted of 5,280 observations at 205 days of age (W205). We assessed fit using two hierarchical reaction norm models: a two-step (HRNM2s) and a one-step (HRNM1s). Model fit was estimated using the Deviance Information Criterion, Deviance Based on Bayes Factors and Deviance based on Conditional Predictive Ordinate. The environmental descriptors were created to group individuals into common production environments based on year, season, herd and sex. Results: The best fit was obtained for the hierarchical reaction norm model with one-step (HRNM1s). Direct heritability estimates for this model ranged from 0.17 to 0.67 and the maternal heritability from 0.02 to 0.11 with increasing environmental gradient. Lower correlations among the sire classifications were obtained in comparison with HRNM1s in environments with low and high management, confirming the presence of genotype x environment interactions. Conclusion: We recommend a wider application of genetic evaluation in buffalo aimed at identifying optimal genotypes within specific environments.

Brazil is the world's fourth largest milk producer; this activity extends throughout the national territory, with productions of approximate 34 billion liters of milk per year. The objective of this work was to evaluate the genotype-environment interaction (GEI) in purebred Holstein cows for milk (M), protein (P), and fat (F) yields. The statistical models used were the standard animal model (AM), which disregards the GEI, and hierarchical reaction norm models with homoscedastic (HRNMHO) and heteroscedastic (HRNMHE) residual variance, and one (HRNMHO1S and HRNMHE1S) and two (HRNMHO2S and HRNMHE2S) steps. HRNMHO1S presented a better fit of the data for all traits, with higher heritability for the best environments. Most bulls presented robust phenotypes; however, GEI was found with a reclassification of the bulls in the environmental gradient. Although few, and less used, bulls with plastic phenotypes were found for all traits, and the use of them can optimize genetic gains in specific environments.

The aim of this study was to describe and analyze the genetic diversity and population structure of Brazilian Somali sheep using pedigree records. Pedigree data of 9,038 individuals born between 1972 and 2018 were analyzed for completeness, gene origin probability, average relationship coefficient (AR), inbreeding coefficient, and genetic conservation index (GCI), using ENDOG v4.8 software. A total of 69.59%, 56.43%, 48.64%, 42.77%, and 34.05% of the examined individuals had pedigrees in the first, second, third, fourth and fifth ancestry, respectively. The total number of founders and ancestors was 833 and 837, whereas the effective number of founders and ancestors was 26 and 22, respectively. The eight main ancestors explained 51.04% of the total genetic variability. The AR and average inbreeding coefficient were 4.05 and 8.74, respectively. The mean GCI was 4.08, ranging from 1.00 to 17.43; three individuals showed a GCI above 17. In conclusion, the Brazilian Somali sheep show considerably high inbreeding coefficients, particularly those individuals born within the last decades. In contrast, some individuals have a high proportion of effective founders in their pedigrees, which can be used strategically for maintaining the genetic diversity of the breed.

Objetivou-se avaliar os índices zoométricos de populações caprinas brasileiras e cabo-verdianas e verificar sua aptidão zootécnica para produção de carne, leite ou mista. Foram amostradas 1.064 cabras adultas das populações: Alpina, Boer, Anglo-Nubiana, Mambrina, Azul, Gurguéia, Sem Raça Definida do Piauí (SRD-PI), Nambi, Marota, Repartida e as populações cabo-verdianas de cinco ilhas (Fogo, São Nicolau, Santiago, São Vicente e Santo Antão). Avaliaram-se altura da cernelha, altura das patas, altura de garupa, comprimento corporal e perímetro torácico. A partir destas medidas foram calculados cinco índices zoométricos baseados na combinação das variáveis anteriores. Estes índices foram submetidos às análises estatísticas descritivas, análise de variância e teste de Scott-Knott (P, The aim of this study was to evaluate the zoometric indices of goat populations in Brazil and Cape Verde and compare them with populations of know aptitude. It was sampled populations 1064 of adult goats: Alpine, Boer, Anglo-Nubian, Mambrina, Azul, Gurguéia, undefined populations of Piauí (UDB-PI), Nambi, Marota e Repartida. It were analyzed body measures of wither height (WH), brisket height (BH), hip height (CH), body length (BL) and thoracic circumference (TP). With this body measures it was calculated the zoometric indices: length-height (LH=CC/WH), height-height (HH=WH/CH), depth-height (DH=TP/WH), length-depth (LD=BL/TP) and witherbrisket (WB=BH/WH). These indices were submitted to follow analysis: descriptive statistical, variance and Scott- Knott test. According to the scale of aptitude was found the populations with higher meat aptitude were: UDB-PI and Nambi. The Anglo-Nubian populations, Gurguéia, Marota and Fogo showed aptitude for milk and meat. The milk aptitude was found to the population of São Nicolau, Santiago, São Vicente, Azul, Santo Antão, Mambrina and Repartida. The zoometric indices are helpful to separate populations according to their aptitudes., Facultad de Ciencias Agrarias y Forestales

Brazilian Pantanal has edaphoclimatic adversities that can strongly affect genotypes. Therefore, sheep breeders should choose animals with a suitable body conformation able to express all the genetic potential. The objective of this work is to describe the body conformation of Santa Ines, Texel and Suffolk ewes raised in the Pantanal region. Four hundred and three adult ewes belonging to the Santa Ines (n = 188), Texel (n = 150) and Suffolk (n = 65) breeds were assessed to obtain eleven measures of length, width, and body perimeters. In addition, the morphometric measures were combined for calculations of conformation indices, milk and meat potential production, and genetic capabilities. Measurements of udder, direction of teats and ears, ear size, and head profile were also evaluated. Breed differences for quantitative variables were evaluated through analysis of variance (ANOVA) while the chi-squared test was conducted for qualitative variables. Subsequently, a factorial analysis was performed on the quantitative variables. Factors were labeled according to the factorial weights of the variables in each factor and used as new variables. The hypothesis of equality between breeds was tested simultaneously considering the new variables through multivariate analysis of variance (MANOVA) and Fischer’s discriminant function. The degree of similarity between breeds was evaluated by using canonical analysis and cluster analysis considering the mean Euclidean distance with grouping by means of complete linkage. According to the qualitative results, Texel and Suffolk ewes did not show phenotypic variability, but a well-defined breed standard. Santa Ines ewes presented variability, thus requiring genetic improvement and breed standardization. Quantitative characteristics (morphometry and indices) varied according to breed of origin. Suffolk and Texel ewes presented the most desirable model for meat production. The main difference between breeds is on body size and structure, which is relevant to the production system used in the Pantanal region.

Brazilian hair sheep constitute a genetic diversity hotspot. These animals are found in the harsh environments of the Brazilian Northwest (semi-arid) region. Genotypes (50K SNP chip) from seven Brazilian sheep breeds (five hair and two coarse wool types) and 87 worldwide breeds were used to test for population structure, admixture and genetic diversity. Moreover, phylogenetic trees evaluating migration events between genetic groups were built. Brazilian Somali, a fat-tailed breed, had a close relationship with East African breeds and clustered distinctly from other Brazilian breeds. Brazilian Blackbelly and Barbados Blackbelly had a close relationship. The Morada Nova breed did not show close relationships with European or African breeds, revealing a single migration event from an Algerian hair breed. Brazilian Fat-tail and Morada Nova share a common ancestor, but the former showed introgressions from Brazilian Somali and Afrikaner breeds, explaining the fat-tail phenotype. The Santa Ines breed received a substantial contribution from Brazilian Bergamasca and showed an admixed origin with recent introgressions from other breeds, mainly from Suffolk. Furthermore, Brazilian Somali and Brazilian Fat-tail are the most endangered sheep genetic resources in Brazil and should be the focus for ex situ conservation programs. In conclusion, Brazilian hair sheep show an African origin and are characterized by diverse genetic composition, reinforcing the need for conservation of these genetic resources, and at the same time, this highly diverse group has variability that can be used in breeding programs.

This study investigated phenotypic differences of zebu females from four breeds using variables of growth, feed efficiency, and age at first calving. Weights throughout the life were recorded, and a growth curve was fitted using the Gompertz model. The growth was also evaluated at standardized ages (205, 365, and 550 days) using the body weight and the total and daily weight gains. The Kleiber index and age at first calving were used as measures of feed efficiency and sexual precocity, respectively, totaling 25 variables. New variables were created using the factor analysis and used in new multivariate analyzes. Only six factors explained 95.41% of the total variance and were used for the subsequent analyses. The factors were defined as maturity, precocity, feed efficiency postweaning, feed efficiency post 1 year of age, puberty, and birth weight. There were differences between breeds according to the multivariate analysis of variance. Each breed appeared in a quadrant on the Biplot graph, showing relationship with different factors, demonstrating the diversity of zebu females. There is a difference in growth, feed efficiency, and sexual precocity in Brazilian zebu females, allowing the identification of potentials of the animals and help breeders and decision-makers.

Our objective was to evaluate the genetic merit of Holstein cattle population in southern Brazil in response to variations in the regional temperature by analyzing the genotype by environment interaction using reaction norms. Fat yield (FY) and protein yield (PY) data of 67 360 primiparous cows were obtained from the database of the Paraná Holstein Breeders Association, Brazil (APCBRH). The regional average annual temperature was used as the environmental variable. A random regression model was adopted applying mixed models with Restricted Maximum Likelihood (REML) algorithm using WOMBAT software. The genetic merit of the 15 most representative bulls, depending on the temperature gradient, was evaluated. Heritability ranged from 0.21 to 0.27 for FY and from 0.14 to 0.20 for PY. The genetic correlation observed among the environmental gradients proved to be higher than 0.80 for both traits. Slight reranking of bulls for both traits was detected, demonstrating that non-relevant genotype by environment interaction for FY and PY were observed. Consequently, no inclusion of the temperature effect in the model of genetic evaluation in southern Brazilian Holstein breed is required.

The successful implementation of genomic selection in more genetically diverse populations (e.g., sheep and goats) require larger training populations. Haplotype-based genomic predictions are hypothesized to perform better in comparison to single-SNP methods mainly due to the possibility of better capturing QTL effects in linkage disequilibrium (LD) with the markers. However, most genomic-prediction studies based on haplotypes were performed in populations with low effective population size (Ne < 150). We aimed to investigate alternative approaches for fitting haplotypes using the single-step GBLUP method (ssGBLUP) in a genetically diverse population (Ne = 400). We simulated a composite sheep population, mimicking real populations based on literature parameters, using the QMSim software, with five replicates. We simulated a HD panel (600K) and two traits with different heritabilites (0.10 and 0.30). Pseudo-SNPs from unique haplotype alleles derived from LD blocks with thresholds of 0.1, 0.3, and 0.6 (LD01, LD03, and LD06, respectively) were used in the analyses. The LD-blocks were constructed using a 50K panel designed from the simulated HD. The training population was composed of 60,000 individuals with phenotypes, 8,000 of them also had genotypes, and 2,000 young genotyped individuals were used as the validation set. The genomic relationship (G) in the ssGBLUP was constructed using both independent markers and pseudo-SNPs (haplotypes). A linear mixed effects model was used to test the effect of the G on the accuracies of prediction, followed by the Tukey test with 5% of significance. No blocks were created with LD06. The accuracies with the 50K panel, LD01, and LD03 for the moderate heritability were 0.41(0.00), 0.40(0.01) and 0.41(0.00), respectively, and 0.24(0.01) 0.23(0.01), and 0.24(0.01) for the low heritability scenario. No statistical differences were observed. Based on our findings, haplotype-based predictions did not improve the accuracy of genomic breeding values in genetically diverse populations.

Our objective was to evaluate the genetic merit of Holstein cattle population in southern Brazil in response to variations in the regional temperature by analyzing the genotype by environment interaction using reaction norms. Fat yield (FY) and protein yield (PY) data of 67 360 primiparous cows were obtained from the database of the Paraná Holstein Breeders Association, Brazil (APCBRH). The regional average annual temperature was used as the environmental variable. A random regression model was adopted applying mixed models with Restricted Maximum Likelihood (REML) algorithm using WOMBAT software. The genetic merit of the 15 most representative bulls, depending on the temperature gradient, was evaluated. Heritability ranged from 0.21 to 0.27 for FY and from 0.14 to 0.20 for PY. The genetic correlation observed among the environmental gradients proved to be higher than 0.80 for both traits. Slight reranking of bulls for both traits was detected, demonstrating that non-relevant genotype by environment interaction for FY and PY were observed. Consequently, no inclusion of the temperature effect in the model of genetic evaluation in southern Brazilian Holstein breed is required.

We provide new records of three globally threatened species of bird belonging to the family Cotingidae: Procnias nudicollis (Vieillot, 1817), Xipholena atropurpurea (Wied, 1820), and Cotinga maculata (Statius Müller, 1776). These findings in non-protected areas of the Brazilian Atlantic Forest and, for C. maculata, at higher altitudes than previously reported, improve our understanding of the distribution of these threatened species and can aid in conservation efforts to protect them.

There are few animal germplasm/gene bank collections in Brazil, and basic studies are needed to attend the future internal and external demands from international partners. The aim of this work was to validate a “proof of concept” that integrates spatial (georeferenced data) and genetic data regarding the local of origin from 3518 DNA samples from 17 different genetic groups or breeds of sheep in the Brazilian Germplasm bank. Spatialisation shows that not all genetic groups have samples in the bank, and collection is concentrated in the conservation nuclei spread nationwide. Only 21% of states with a specific breed have samples in the gene bank. The mean number of animals sampled per collection was 32, while the mean distance travelled to collect samples was 262 km from the conservation nuclei. For example, the Brazilian Somali were only collected in the conservation nucleus in Ceara State. No samples were collected to date for the Cariri breed, which is recognised by the Brazilian Ministry of Agriculture. Only two farms and one breed in the bank are from the northern region. Of the 27 states, there are samples in the gene bank of sheep from 13, so several states have no samples, requiring collection from herds outside the official system of conservation to make sure that studies using this germplasm realised are not biased. Significant genetic differences are seen above 332 km, which should guide future sampling efforts. Suggestions are given for improving the quantity, quality and diversity of samples in the gene bank.

The relationship between body development and external measures in sheep could provide useful information to define the optimal slaughter time as well as the adequate nutritional management. Thus, the objective of this study was to evaluate the morpho-functional diversity of Dorper sheep crossed with Brazilian native breeds using in vivo morphometric analysis. The animals evaluated were from crosses of Dorper with Morada Nova, Rabo Largo and Santa Ines sheeps. The animals were slaughtered at 120 and 240 days of age. Body and carcass measures, weight of meat cuts and growth were evaluated. The crossbred animals were analyzed by sex, totaling six treatments. A factorial analysis was performed using two sets of data: the in vivo morphometric measures, and all the other characteristics and these factors were used as new variables. The differences among treatments were analyzed using MANOVA and canonical analysis. The meat cuts, conformation, marketability adaptation, and early maturity of the animals slaughtered at 120 days, as well as the meat cuts, conformation, adaptation, early maturity, and hindquarter of the animals slaughtered at 240 days were evaluated. As regards body measurements, at both slaughter ages, the following factors were discriminated: height, robustness, length, and thoracic circumference. Animal slaughtered at 120 days of age showed greater differences whereas at 240 days the differences diminished allowing to individuate which treatments were more adaptive or productive. Crosses ½ Dorper × ½ Santa Ines (male and female), and ½ Dorper × ½ Rabo Largo male slaughtered at 240 days seem to show higher productivity and better marketability abilities. The other crosses tend to have a more rustic profile (less productive) and smaller size, reaching however adult size earlier and showing better adaptive characteristics, which allows to decide for slaughtering at younger ages.

Evaluating phenotypic diversity makes it possible to identify discrepancies in aptitudes among animals of different genetic bases, which is an indicator of adaptive or selective differences between populations. The objective of this work was to evaluate the morphofunctional diversity of 452 male and female adult equines (Arabian, Quarter Mile, Pantaneiro, and Criollo breeds, and undefined crossbreeds of horses and mules) raised in the Pantanal biome (Brazil). Linear measurements were performed to estimate conformation indexes. Initially, a discriminant analysis was performed, regardless of the animal's size, followed by factor analysis. The factors were characterized and used as new variables. The diversity among equines and their relationship with the factors were evaluated using multivariate analysis. The factors were classified according to their decreasing importance: balance, rusticity, and robustness for the measurement factors; and load, ability, conformation, and equilibrium for the index factors. The genetic groups of equines have well-defined morphofunctional characteristics. The main differences are based on the rusticity and ability typologies in relation to those based on performance. Equines introduced to the Pantanal biome presented a more robust and compact body with good conformation. As a result, these horses may have superior athletic performance during equestrian activities when compared to the Pantaneiro local breed. However, this biotype may represent less rusticity (less adaptive capacity). Therefore, the regional breed can be equal or better in equestrian activities than breeds introduced to the Pantanal biome. Thus, breeders may cross horses from local breeds as an alternative to those introduced. Undefined crossbred male equines presented a different profile from the Pantaneiro breed, which may indicate little use of crossbreeds in breeding.

Many allopatric populations of the pearl cichlid Geophagus brasiliensis show remarkable morphological, chromosomal, and DNA sequence divergence. As a result, Geophagus brasiliensis is regarded as a species complex, combining recent descriptions of new species and several uncertainties about their actual richness. In the present work, we evaluated the number of evolutionary units in this fish complex along hydrographic basins in northeastern Brazil by using the DNA barcode, species delimitation algorithms and phylogenetic analyses. A total of 14 molecular operational taxonomic units (MOTUS) were identified with high support values and mean differentiation within and among groups of 0.4 and 12.7%, respectively. The DNA sequences supported Geophagus itapicuruensis as a valid taxon, besides indicating likely undescribed species. Moreover, the evolutionary units in coastal basins of useful to infer the evolutionary units in a cryptic and widespread fish group from the Neotropical region. Finally, the undescribed taxa in coastal basins of northeastern Brazil were clearly differentiated from Geophagus brasiliensis sensu stricto. The present data highlight the importance of conserving regional ichthyofauna since unique evolutionary lineages are potentially threatened by environmental degradation, invasive species and construction of dams.

The objective of this work was to assess the effect of editing and modeling of milk production data for genetic evaluation of Murrah buffaloes. Six strategies for evaluating milk production were analyzed: observed milk production (OMP); adjustment of milk production data to 305 (MP305) and 270 (MP270) days of lactation; removal of the 5 (MP5%) and 10% (MP10%) shortest lactation periods; and milk production along the lactation period as linear covariate (MPCO). Genetic parameters were estimated using the Bayesian inference, with heritability estimates of 0.19 to 0.23 and repeatability estimates of 0.35 to 0.36. Sires classified by OMP were high correlated to those classified by the other models, however, correlations to MP270, MP305 and MPCO decreased when considering only the best 20% sires. OMP showed greater differences in absolute mean deviations when compared with MPCO, MP270 and MP305. The strategies of analysis had similar heritabilities and stabilities. However, changes in the ranking of sires with better classifications, due to overestimation of genetic values, as occurred in the models MP305, MP270 and MPCO, may lead to a decrease in the genetic progress of the herd. Resumo: O objetivo deste trabalho foi verificar as consequências da edição e modelagem da produção de leite para avaliação genética de bubalinos da raça Murrah. Foram analisadas seis estratégias para avaliação da produção de leite: produção de leite observada (PL_OBS); ajuste para a produção de leite aos 305 dias (PL_305) e aos 270 dias (PL_270); exclusões dos 5 e 10% menores períodos de lactação (PL_5% e PL_10%) e duração da lactação como covariável linear (PL_CO). Os parâmetros genéticos foram estimados por meio de inferência Bayesiana, com estimativas de herdabilidades e repetibilidades de 0,19 a 0,23 e 0,35 a 0,36, respectivamente. Touros classificados pelo PL_OBS apresentaram altas correlações com os que foram classificados pelos outros modelos. Contudo, ao considerar apenas os 20% melhores touros, verificou-se diminuição das correlações de PL_270, PL_305 e PL_CO com PL_OBS. Maiores diferenças dos desvios médios absolutos do PL_OBS foram com PL_CO, PL_270 e PL_305. As estratégias de análise apresentaram herdabilidades e estabilidade semelhantes. Contudo, as inversões de posições dos touros com melhores classificações, como consequencia das superestimativas dos valores genéticos nos modelos PL305, PL270 e PL_CO podem acarretar em diminuição do progresso genético nos rebanhos.

The identification of selection signatures allows a better comprehension of evolutionary processes, gene function and organization in the genome. Thus, the objective of this study was to identify and characterize genomic regions subject to selection, comparing two Caracu breed lines, one selected for milk (Caracu Caldeano) and other for meat production (Caracu). Animals were genotyped using the Illumina Bovine HD Genotyping BeadChip which included ~ 777 K SNP. The identification of selection signatures was based on population differentiation (F ST ). Twenty-one genomic regions related to meat and milk production and adaptation characteristics were identified. The genes identified as candidate to be under selection in this study included those related to muscle growth and meat quality ( TFCP2, KIAA1244 , CDH23 and FAM186B) , milk compounds synthesis ( MUC19 ), reproductive metabolism ( SLC39A11 ). Genes related to adaptative traits including resistance to metabolic diseases ( C6 ), and epidermal development and resistance to high temperatures ( KRT86 ) and ( KRT83 ) were also identified. The observed relevant genomic regions of Caracu and Caracu Caldeano differed, indicating that specific selection signatures of each line were successfully identified and may represent the consequence of adaptation to the local environment and type of animal production.

Genetic diversity is one of the most important issues in studies on conservation of cattle breeds and endangered species. The objective of this study was to estimate the levels of genetic differentiation between locally adapted taurine (Bos taurus taurus) and zebu (Bos taurus indicus) breeds in Brazil, which were genotyped for more than 777,000 SNPs. The fixation index (F ST), principal component analysis (PCA), and Bayesian clustering were estimated. The F ST highlighted genetic differentiation between taurine and zebu breeds. The taurine lines, Caracu and Caracu Caldeano, had significant genetic differentiation (F ST close to 5%) despite their recent selection for different uses (meat and milk). This genetic variability can be used for conservation of locally adapted animals, as well as for breeding programs on zebu breeds. Introgression of zebu in locally adapted breeds was identified, especially in Curraleiro Pe-Duro breed. The Gyr breed, however, had low breed purity at genomic level due to its very heterogeneous mixing pattern.

The objective of this work was to estimate the phenotypic diversity in Jafarabadi, Murrah, and Mediterranean buffalo cows (Bubalus bubalis). Thoracic perimeter, withers-and-rump height, body length, and biiliac, external biischiatic, external ilioischiatic, sacropubic, and mean biiliac diameters were measured. The following indexes were calculated: anamorphosis index, pelvic index, withers-to-rump ratio, body index, lateral-body index, relative body index, body capacity indexes 1 and 2, transversal pelvic index, longitudinal pelvic index, and thoracic-perimeter-to-withers ratio index. The effect of breed was evaluated using univariate (mean tests) and multivariate (size-free discriminant analysis and Fisher’s linear discriminant function) analyses. The diversity among the breeds and their correlation with the variables were also evaluated using biplot graphs developed from principal component analysis. The breeds evaluated show a rectilinear, midline body model with similar capacity of muscular tissue development in body parts from which the most valuable cuts are extracted, and intermediate suitability for meat and milk production. The Jafarabadi breed has a larger body size, with a rear portion wider than longer, while the Murrah and Mediterranean breeds show similar biotypes, mainly differentiated in the pelvic region. Resumo: O objetivo deste trabalho foi estimar a diversidade fenotípica em búfalas (Bubalus bubalis) das raças Jafarabadi, Murrah e Mediterrâneo. Mensuraram-se perímetro torácico, altura de anterior e de garupa, comprimento do corpo e diâmetros do biilíaco, biisquiático externo, ilioisquiático externo, sacropúbico e biilíaco médio. Calcularam-se os seguintes índices: de anamorfose, pélvico, relação cernelha-garupa, corporal, corporal-lateral, corporal relativo, capacidade corporal 1 e 2, pélvico transversal, pélvico longitudinal e relação perímetro torácico-cernelha. Avaliou-se o efeito de raça por meio das análises univariada (teste de médias) e multivariada (análise discriminante independente do tamanho e função discriminante linear de Fisher). Também avaliaram-se a diversidade entre as raças e a sua relação com as variáveis, por meio de gráficos biplot, elaborados a partir da análise de componentes principais. As raças apresentam modelo corpóreo retilíneo, mediolíneo e com capacidade igual para desenvolvimento de tecido muscular em locais de onde são extraídos cortes nobres, com aptidões intermediárias para produção de carne e leite. A raça Jafarabadi apresenta maior porte corporal, assim como uma porção traseira mais larga do que comprida, enquanto a Murrah e a Mediterrâneo apresentam biótipos próximos, diferenciados principalmente na região pélvica.

Genetic breeding programs generally evaluate animals considering the same objectives, but the indices used in the selection criteria can vary. This can give rise to distinct bull rankings in each program. Thus, we aimed to create alternatives for the referral of bulls for mating through multivariate analyses. We used information from the summaries of two genetic evaluation programs (1 and 2) with Nellore bulls. Characteristics were separated into groups: weight, carcass and reproduction. Groups were formed using the mean Euclidean distance and the Tocher optimization method. The means of each trait among the animals allocated to the same group were used to compose the following subindexes: weight gain (siWG), carcass (siCG) and reproduction (siRG). Based on the mean of the group subindex classification, we calculated the average index of group classification (iAGc). When classifying the best groups by characteristics, we observed an increase (superiority of some bulls) in the estimated breeding values (EBVs) by comparison with the total number of bulls evaluated by the programs, selected animals and best 10 final indexes of the programs. There was a change in bull classification when using the iAGc in relation to the classification using the final indexes of the programs. The coefficient of simple coincidence showed that there was a change in bull classification between programs, both between deciles of the final indexes and groups of characteristics. The subindexes siWG, siCG and siRG are important for correcting specific problems in herds. The iAGc should be used instead of the final index of the programs, providing more options for the selection of bulls for mating.

The study of locally adapted breeds has the potential to underpin the discovery of genes involved in economically and ecologically important traits. Brazilian locally adapted sheep breeds have distinctive characteristics that could be of value for specialized production systems. Therefore, the main objective of the present study was to identify genomic regions that may have been under selection and therefore may explain ecological and production differences observed among three important Brazilian locally adapted sheep breeds. Animals from the Brazilian Creole, Morada Nova and Santa Ines breeds were genotyped using the Illumina Ovine SNP50 BeadChip. The identification of selection signatures was based on two groups of methodologies: differentiation among populations (FST) and linkage disequilibrium (iHS and RsB). Taken together, these analyses allowed for the identification of 86 candidate genes. Functional analysis revealed genes related to immunity, nervous system development, reproduction and sensory perception. A number of genes are of particular interest including: RXFP2, which has recently been associated with the presence/absence and morphology of horns in sheep; the TRPM8 gene, involved in regulation of body temperature at low temperatures; DIS3L2, PLAG1 and NIPBL, associated with height variation; and finally, SPEF2 and SPAG6, important for spermatogenesis. Selective sweeps were identified using multiple methods, and in a number of cases sweep regions contained genes with a demonstrated role in phenotypic variation. The genomic distribution of the sweep regions differed between populations, suggesting that breed specific signatures were successfully identified that may reflect the consequence of local adaptation.

We evaluate genotype × environment (G × E) interactions for age at first calving (AFC) and calving interval (CI) of Nellore cattle in northeastern Brazil using four hierarchical reaction norm models (HRNMs). The best-fit model for the traits was the one step heteroscedastic hierarchical reaction norm model. Heritability was close to zero in the worst environments and increased as the environments improved (from 0.06 to 0.12 for AFC and from 0.01 to 0.03 for CI). The correlations between the intercept and the slope of the reaction norms for CI and AFC were from medium to high magnitude (0.75 ± 0.10 and 0.90 ± 0.04, respectively), indicating that animals with higher average breeding values had the greatest responses to the improvement of environmental conditions. The variation in heritability indicates different response to selection according to the environment in which the animals of the population are evaluated. The G × E was evident in bulls with more female offspring. In conclusion, our data demonstrate that selection for AFC in medium- and high-level environments leads to higher genetic gains.

The aim of this study was to explore spatial patterns of genetic structure in sheep breeds sampled in Brazil using Single Nucleotide Polymorphisms (SNPs) in order to evaluate whether or not the genetic and geographic distances are interrelated in this species. Samples genotyped using the 50KSheepSNPChip (Illumina) included 215 animals from eight different sheep breeds. All collection sites were georeferenced and data analyzed to determine geographic patterns from genetic data. To evaluate the correlation between genetic and geographic distances Mantel tests, Allelic Aggregation Index Analyses (AAIA), and spatial autocorrelation were performed. Genetic Landscape Shape procedure and Monmonier’s Algorithm were used to generate graphical visualization of the genetic distances across the landscape. The observed correlation observed between genetic and geographical distances was 0.552 (P

Dairy cattle production is distributed throughout the Brazilian regions. However, Brazilian producing regions are different in air temperature and humidity, diet, birth season, and other factors that may alter the reproductive performances of cows. The age of the cow at first calving (AFC) is a good indicator of sexual precocity since it shows the beginning of the female reproductive life and has a great influence on cow replacement costs. Researches on genotype-environment interaction (GEI) show the importance of using specific bulls for the different production systems in Brazil since most semen used in the country is imported. The objective of this work was to evaluate GEI for AFC in Holstein cows in Brazil, using reaction norms. The statistical models used were the standard animal model, which disregards the GEI, and hierarchical reaction norm models with homoscedastic (HRNMHO) and heteroscedastic (HRNMHE) residual variance, and one (HRNMHO1S and HRNMHE1S) and two (HRNMHO2S and HRNMHE2S) steps. HRNMHO1S presented better fit to the data, with lower heritability for environments with lower AFC, and higher heritability for environments with higher AFC. The GEI found was complex, with a reclassification of bulls, denoting the importance of considering GEI for evaluation and selection of bulls for different production levels. The reduction of AFC is possible when using breeding bulls adapted to the tropical and subtropical conditions of Brazil.

The genotypes express differentiated responses depending on the environmental conditions and this can cause a re-ordering of the genotype in the environmental gradient. Therefore, our objective was to evaluate the genotype-environment interaction (GxE) for age at first calving (AFC) in Limousine and Charolais cattle raised in Italy, using reaction norm model (RNM). The data comprises information from 35,255 Limousine and 7,339 Charolais animals, born between 1999 and 2017. The standard animal model (AM), which ignores the G x E interaction, and the hierarchical models of reaction norms with homogeneous and heterogeneous residual variances with one and two steps (MHNRHO1P, MHNRHO2P, MHNRHE1P, and MHNRHE2P) were used for the analysis. In both breeds, the MHNRHOP1 model presented the best fit. In favorable environments (lower AFC), there was less phenotypic variation; the AFC expression of the animals was close and this may have caused lower estimates of additive genetic effects ( σ A 2 ) and consequently lower heritabilities (h²). In Charolais, the h² for the animal model (AM) was 0.13, whereas for MHNRHOP1 the value varied throughout the environmental gradient from 0.06 to 0.13, for low and high AFC environments, respectively. In Limousine breed, a lower h² (0.06) was observed in the animal model (AM), while in the MHNRHOP1 model it varied from 0.00 to 0.15. In both breeds, bulls with higher genetic merits for one environment were not for another, demonstrating the existence of the GxE. In Charolais and Limousine breeds, more than 93.75% and 87.72% of the bulls presented extremely robust or robust genotypes, respectively. Although most bulls are robust, there are bulls reactive to the environment, which can lead to incorrect selection of breeders. The results suggest that the genotype-environment interaction should be considered in the selection for AFC in both breeds raised in Italy.

The fish genus Astyanax represents a suitable model to test the role of chromosomal changes in population structure and speciation. Therefore, we performed a detailed karyotypic analysis of Astyanax aff. fasciatus from rivers in South America with incorporation of multivariate analyses as an innovate approach to infer chromosomal diversity. Ten populations of Astyanax aff. fasciatus from distinct coastal basins in northeastern Brazil were cytogenetically analyzed using Giemsa, Ag-NOR and fluorochrome staining, C-banding, mapping of rDNA and a genus-specific satellite DNA (As51). A multivariate analysis of chromosomal data was carried out to provide a consensus dendrogram of intraspecifical relationships. In spite of sharing the same diploid number, similar C-banding patterns, the populations varied in karyotype formulae and location of 18S and 5S rDNA cistrons, GC-rich segments, and As51 satDNA. The multivariate analysis showed CG-specific markers are poorly correlated to 18S rDNA. The dendrogram revealed that intraspecifical chromosomal differences are not explained by geographic distance. Instead, this variation seems to be related to the biogeographic history of northeastern Brazil and/or to the presence of unique evolutionary units under incipient speciation. Finally, we strongly recommend the incorporation of statistical analysis in cytogenetic studies of fish, particularly in groups of remarkable intraspecifical diversity as Astyanax. Such studies are useful because they provide a reliable interpretation of chromosomal variation.

Made available in DSpace on 2018-11-12T17:25:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-01. Added 1 bitstream(s) on 2021-07-14T17:50:15Z : No. of bitstreams: 1 S0100-204X2015000700615.pdf: 529779 bytes, checksum: 681efc3c925914a355208611f6e530cf (MD5) Resumo: O objetivo deste trabalho foi verificar a presença da interação genótipos x ambientes (GxA) para peso aos 365 dias de idade, em bubalinos da raça Mediterrâneo, com o uso de modelos de normas de reação via regressão aleatória. O modelo animal padrão e os modelos de normas de reação foram testados, tendo-se avaliado o modelo hierárquico norma de reação (MNR) com um e com dois passos. O modelo hierárquico homocedástico de norma de reação com um passo (MHNRHO1P) apresentou o melhor ajuste, com base em três critérios de comparação. As estimativas de herdabilidade direta para esse modelo variaram de 0,19 a 0,78, conforme a melhoria do ambiente. Além disso, houve mudança dos valores genéticos diretos (efeito escala) de alguns reprodutores, o que indica a existência de interação GxA. As correlações de Spearman foram altas, tanto na comparação do modelo animal padrão com os MNR, como na comparação entre os níveis de baixa, média e alta qualidade no MHNRHO1p. Portanto, embora haja interação GxA, a classificação dos reprodutores não é significativamente afetada pelos modelos. A maioria dos bubalinos é formada por animais de genótipo robusto, que são menos sensíveis a mudanças ambientais. Abstract: The objective of this work was to verify the presence of the genotypes x environments interaction (GxE) for weight at 365 days of age in the Mediterranean breed of buffaloes, using models of reaction norms through random regression. The standard animal model and the models of reaction norms were tested, and the hierarchical model reaction norm (MRN) was evaluated with one and two steps. The homoscedastic hierarchical model of reaction norms with one-step (HMRNHO1s) had the best fit, based on three criteria for comparison. The direct heritability estimates for this model ranged from 0.19 to 0.78, with environment improvement. Besides, direct breeding values (scale effect) changed for some breeders, which indicates the existence of GxE interaction. The Spearman correlations were high, both in the comparison between the standard animal model and MRN, as in the comparison between low, medium, and high management levels in HMRNHO1s. Therefore, although there is GxE interaction, the ranking of breeding animals is not significantly affected by the models. The majority of buffaloes is formed by animals with robust genotypes, which are less sensitive to environmental changes. Instituto Federal do Norte de Minas Gerais Universidade Estadual Sudoeste da Bahia Departamento de Ciências Biológicas Universidade Estadual Paulista Departamento de Produção Animal Universidade Estadual Paulista Departamento de Produção Animal

Direct diagnoses were made by using - blood smears and nested PCR (nPCR) tests on 309 blood samples from crossbred dairy cattle in the municipality of Ibicaraí, Bahia. From diagnostic blood smear slides, the observed parasitic frequencies were 31.1% for Anaplasma marginale and 20.4% for Babesia sp. From nPCR diagnoses, they were 63% for A. marginale, 34% for Babesia bigemina and 20.4% for Babesia bovis. There were significant differences (P

O objetivo com esta pesquisa foi estimar parâmetros genéticos e predizer tendências genéticas e fenotípicas para pesos aos 205 (P205), 365 (P365) e 550 (P550) dias de idade, em animais da raça Nelore nascidos no período de 1975 a 2011 no Estado da Bahia. Os dados foram analisados através de modelos bayesianos uni e bicaracterísticos com o programa GIBBS3F90. Os modelos utilizados para as três características incluíram os efeitos aleatórios genéticos (direto e materno), de ambiente permanente maternal, a covariável idade da vaca ao parto (efeito linear e quadrático), além do efeito fixo de grupo de contemporâneos. As herdabilidades (direta) para P205, P365 e P550 apresentaram valores inferiores aos relatados na literatura, contudo, existe possibilidade de ganho genético por meio da seleção. As predições de tendências genéticas e fenotípicas para as características foram obtidas pela regressão linear ponderada da média da variável dependente (valores genéticos e pesos observados) sobre o ano de nascimento. As tendências para P365 e P550 preditas demonstram que houve algum progresso genético para estas duas características, porém, inferiores ao peso aos 205 de idade. Os valores observados indicam pequeno, porém, favorável progresso genético para o efeito direto nas três pesagens. O progresso fenotípico foi alto nas três características, mostrando melhoria ambiental, no estado da Bahia, no decorrer do período estudado.

Made available in DSpace on 2020-12-10T17:02:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The research aim was to evaluate the genotype-environment interactions (GxE) through a study of the reaction norms of Nellore cattle raised in the North and Northeast regions of Brazil at the age at first calving (AFC), with scrotal circumference at 365 and 450 days of age (SC365 and SC450), gestation length (GL) and accumulated productivity (ACP). Bayes hierarchical models with defined parameters at structured levels or stages were used. The Markov chain Monte Carlo method was used to obtain genetic parameter estimates. The environmental gradient of each trait was defined using a 99% credibility interval of the contemporary group's solutions. The animal model showed a better fit for AFC data, and the two-step reaction norms model was the best for the other characteristics. Heritabilities were 0.21 +/- 0.01 for AFC; and ranged from 0.27 +/- 0.04 to 0.58 +/- 0.02, 0.26 +/- 0.05 to 0.57 +/- 0.02, 81 +/- 0.03 to 0.03 +/- 0.02, 0.05 +/- 0.02 to 0.86 +/- 0.03 along the environmental gradient for SC365, SC450, GL and ACP, respectively. Correlations between intercept and slope of the reaction norms allied with reaction norms graphic plots of the ten sires with the greatest number of calves suggest the presence of GxE complex for SC365 and SC450, and thcE scale effect for GL and ACP. However, high correlations between the environments indicate that the GxE for SC450 and ACP is of a low magnitude and its inclusion in genetic evaluations would not influence the population selection. State Univ Southwest Bahia, Itapetinga, BA, Brazil State Univ Southwest Bahia, Dept Biol Sci, Jequie, BA, Brazil Fed Inst Amapa, Porto Grande, Amapa, Brazil Natl Assoc Breeders & Researchers, Ribeirao Preto, SP, Brazil Univ Fed Ceara, Juazeiro Do Norte, Ceara, Brazil Sao Paulo State Univ Unesp, Sch Agr & Vet Sci, Jaboticabal, SP, Brazil Sao Paulo State Univ Unesp, Sch Agr & Vet Sci, Jaboticabal, SP, Brazil CAPES: 001

O objetivo deste trabalho foi avaliar a diversidade fenotípica de uma população de galinhas Peloco e compará-la a três linhagens comerciais de frango de corte do tipo caipira. Avaliações foram feitas quanto a características de: peso de carcaça, peito, coxa e sobrecoxa; altura, largura e comprimento do peito; e comprimento da coxa e da sobrecoxa. Os dados foram submetidos às análises de variáveis canônicas e à análise discriminante independente do tamanho (ADIT). Os resíduos da ADIT foram utilizados na análise de agrupamento pelos métodos de Tocher e UPGMA. As duas primeiras variáveis canônicas foram suficientes para explicar 94,66% da variação total entre os fenótipos. O peso da carcaça teve a maior contribuição para a variação (59,91%) entre os grupos de aves, seguido de peso da coxa (12,63%) e largura do peito (11,75%). Ambos os métodos de agrupamento resultaram na formação de dois grupos: um de linhagens comerciais e outro da raça Peloco. O isolamento da Peloco é consequência da ausência de seleção para as características estudadas. Além disso, a presença de variabilidade dentro da raça Peloco mostra a existência de animais com maior potencial quanto ao peso de carcaça, o que possibilita o melhoramento da raça. The objective of this work was to evaluate the phenotypic diversity of a Peloco chicken population and to compare it with three free-range broiler commercial lineages. Evaluations were done for the following characteristics: the weights of carcass, breast, drumstick, and thigh; the height, width, and length of breast; and the lengths of drumstick and thigh. Data were submitted to canonic variable analyses and to size-independent discriminant analysis (ADIT). The ADIT residues were used in Tocher´s grouping analysis and in UPGMA method. The first two canonic variables were sufficient to explain 94.66% of the total variation among phenotypes. Carcass weight had the greatest contribution for the variation (59.91%) among the bird groups, followed by drumstick weight (12.63%) and breast width (11.75%). Both grouping methods resulted in the formation of two groups, one of the commercial lineages, and other of the Peloco breed. Peloco isolation is a consequence of the selection absence for the studied characteristics. In addition, the presence of variability in Peloco breed shows the existence of animals with a greater potential for carcass weight, which makes it possible the improvement of this breed.

In the present study, alternative and traditional nonlinear models to describe growth curves of Morada Nova sheep reared in the state of Bahia, Brazil, were applied. The nonlinear models were: Schnute, Mitscherlich, Gompertz, Logistic, Meloun I Meloun II, III Meloun, Gamito and Meloun IV. The model adjustment was evaluated by using: Adjusted Coefficient of Determination (R²aj), Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), Mean Squared Error of Prediction (MEP) and Coefficient of Determination of Prediction (R²p). The selection of the best model was based on cluster analysis, using the evaluators as variables. Six out of the nine tested models converged, while Meloun I and Meloun IV were equally effective in explaining animal growth, without significant influence of sex or type of parturition over the curve parameters. The models Meloun I and IV have the best adjustment and reveal a remarkable reduction of weight gain after 150 days of age, which indicates special attention should be given to feeding at this stage.

Data are typically discarded when there are inconsistencies in a database, or when information is discrepant or out of range for the biological characteristics of the species being analyzed. However, such loss of information could have considerable implications for genetic evaluation of cattle. Here, we use different models to estimate genetic parameters for age at first calving in order to prevent data elimination. We used five approaches based on trait distribution to define the limits of censure/disposal: linear model, censorship, penalty and missing methods, and threshold model (binary and polychotomous). Data splitting and Pearson correlation were used to evaluate fitting and comparison of models. The lowest heritabilities were estimated for the missing method and the binary model. Exclusion of outliers from the data considerably affects the estimation of genetic parameters and the ranking of sires. Moreover, models that suffered from data elimination generated the worst classifications in terms of the comparison of models. Researchers should be extremely careful when deciding to discard data. For example, an age at first calving up to 72 months could be considered an outlier for other countries or even other areas in Brazil. Although this value is very high, it could be realistic under arid or semi-arid conditions. In these situations, the penalty or censure models are the most appropriate methods of analyses.

Melipona mandacaia is a stingless bee species responsible for the pollination of many native plants in Brazil, South America. In spite of its ecological and economic importance, natural populations of M. mandacaia have been depleted because of deforestation. In order to evaluate the interpopulation morphometric structure of remaining populations, we carried out geometric morphometric studies based on fore wing shape in this native bee species. The grouping analysis by UPGMA revealed three distinct clusters and significant differences in fore wing size were observed (p

The objective of this study was to evaluate the influence of inbreeding depression on traits of buffaloes from Brazil. Specifically, the traits studied were body weight at 205 and 365 days of age, average daily gain from birth to 205 days (ADG_205), average daily gain between 205 and 365 days (ADG205_365) in Mediterranean buffaloes, and milk yield, lactation length, age of first calving and calving intervals in Murrah buffaloes. Inbreeding effects on the traits were determined by fitting four regression models (linear, quadratic, exponential and Michaelis-Menten) about the errors generated by the animal model. The linear model was only significant (P 0.05) for any of the traits. Weight at 205 and 365 days of age decreased 0.25 kg and 0.39 kg per 1% of increase in inbreeding, respectively. The inbred animals (F = 0.25) produced less milk than non-inbred individuals: 50.4 kg of milk. Moreover, calving interval increased 0.164 days per 1% of increase in inbreeding. Interestingly, inbreeding had a positive effect on age at first calving and lactation length, decreasing age of first calving and increasing lactation length.

Records of a pig population used for dry-cured ham production were used to evaluate genetic groups by multivariate analysis. The investigated genetic groups were as follows: DULL=Duroc×(Landrace×Large White), DULA=Duroc×Landrace, DUWI=Duroc×Large White, WIWI=Large White and DUDU=Duroc. Two groups were obtained for the carcass traits hot carcass weight (HCW), backfat thickness (BT) and loin depth (LD), with the groups including 597 and 341 animals harvested at 130 kg and at 160 kg weights, respectively. Two groups were also found for ham traits gross ham weight (GHW), trimmed ham weight (THW), ham inner layer fat thickness (HIFT), ham outer layer fat thickness (HOFT), pH (PH), and Gofo value, with 393 and 91 animals harvested at 130 kg and 160 kg weights, respectively. The analysis was performed within each group of traits and harvest weights, and the animals without records were excluded. The first and the second canonical variables explained 97.5% and 93.6% of the total variation for the carcass traits at 130 kg and 160 kg, respectively, and 88.8% of ham traits at 130 kg. In the dispersion graph concerning the canonical means, a significant distance was observed between the genetic groups DUDU and WIWI for the carcass traits at 130 kg and 160 kg and the ham traits at 130 kg. The 50% Duroc animals exhibited little dispersion regarding the carcass traits at 130 kg and 160 kg and were not divergent from the DUDU genetic group for the ham traits at 130 kg. In a cluster analysis using the single linkage method, DULL, DULA and DUWI were grouped with a high similarity level for the carcass traits at 130 kg and 160 kg and ham traits at 130 kg. Using the Tocher optimization method, 50% Duroc crossbred and 100% Duroc purebred animals were grouped for the ham traits at 130 kg, suggesting that for ham traits, 50% Duroc animals were similar to 100% Duroc purebred animals. In this context, the genetic groups Duroc×Large White, Duroc×Landrace and Duroc×(Landrace×Large White) are recommended for use in producing dry-cured ham.

The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability in the Murrah dairy breed of water buffalo (Bubalus bubalis) in Brazil. Pedigree analysis was performed on 5,061 animals born between 1972 and 2002. The effective number of founders (fe) was 60, representing 6.32 % of the potential number of founders. The effective number of ancestors (fa) was 36 and the genetic contribution of the 17 most influent ancestors explained 50 % of the genetic variability in the population. The ratio fe/fa (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.66. Completeness level for the whole pedigree was 76.8, 49.2, 27.7, and 12.8 % for, respectively, the first, second, third, and fourth known parental generations. The average inbreeding values for the whole analyzed pedigree and for inbreed animals were, respectively, 1.28 and 7.64 %. The average relatedness coefficient between individuals of the population was estimated to be 2.05 %-the highest individual coefficient was 10.31 %. The actual inbreeding and average relatedness coefficient are probably higher than estimated due to low levels of pedigree completeness. Moreover, the inbreeding coefficient increased with the addition of each generation to the pedigree, indicating that incomplete pedigrees tend to underestimate the level of inbreeding. Introduction of new sires with the lowest possible average relatedness coefficient and the use of appropriate mating strategies are recommended to keep inbreeding at acceptable levels and increase the genetic variability in this economically important species, which has relatively low numbers compared to other commercial cattle breeds. The inclusion of additional parameters, such as effective number of founders, effective number of ancestors, and fe/fa ratio, provides better resolution as compared to the inclusion of inbreeding coefficient and may help breeders and farmers adopt better precautionary measures against inbreeding depression and other deleterious genetic effects.

The first registers of Somali sheep in Brazil are from the beginning of the 1900s. This breed, adapted to the dry climate and scarce food supply, is restricted in the northeast region of the country. Molecular marker technologies, especially those based on genotyping microsatellite and mtDNA loci, can be used in conjunction with breeding (pedigree analysis) and consequently the maintenance of genetic variation in herds. Animals from the Brazilian Somali Conservation Nuclei from Embrapa Sheep and Goats in Ceara State were used to validate genetic monitoring by traditional pedigree methods and molecular markers. Nineteen microsatellite markers and 404 base pairs from the control region of mtDNA were used. For total herd diversity, an average 5.32 alleles were found, with expected heterozygosity of 0.5896, observed heterozygosity of 0.6451, 0.4126 for molecular coancestrality, and coefficient of inbreeding (F IS) was −0.095. Comparing molecular coancestrality means over the years, there was a consistent increase in this parameter within the herd, increasing from 0.4157 to 0.4769 in 2 years (approx. 12% variation). Sixteen mtDNA haplotypes were identified. Inbreeding and other estimates from genealogical analyses confirm the results from molecular markers. From these results, it is possible to state that microsatellites are useful tools in genetic management of herds, especially when routine herd recording is not carried out, or there were gaps in recent generations. As well as pedigree control, genetic diversity can be optimized. Based on the results, and despite herd recording in the herd of Brazilian Somali of Embrapa Sheep and Goats, additional management measures need to be carried out in this herd to reduce inbreeding and optimize genetic variation.

The objective of the present study was to evaluate the genetic structure of Gyr cattle selected for milk production. Files of pedigree and production were composed of 27,610 animals. The ENDOG program was used for the calculation of individual inbreeding coefficient (F) and coefficient of average relatedness (AR), effective number of animals(Ne), effective number of founders (f e) and ancestors (f a), and generation interval (GI). Individual inbreeding coefficients and average relatedness in the population were 2.82% and 2.10%, respectively. It was observed a reduction in the effective number of animals, especially after publication of the results of the first progeny test. The estimated effective number of founders was 146 and 75 for the ancestrals. Out of those, only 28 ancestors accounted for the origin of 50% of the population genes. The average generation interval was 8.41 years and it was longer for males than for females. For maintaining genetic variability in future generations, it should be invested mating strategies that reduce inbreeding and which do not use massively only some high breeding value sires. O objetivo neste trabalho foi avaliar a estrutura genética da raça Gir selecionada para produção de leite. Os arquivos de pedigree e de produção eram compostos de 27.610 animais. Utilizou-se o programa ENDOG para cálculo dos coeficientes individuais de endogamia (F) e coeficiente de relação médio (AR), número efetivo de animais (Ne), de fundadores (fe) e de ancestrais (fa) e do intervalo de gerações (GI). Os coeficientes individuais de endogamia e de relação médios da população foram 2,82 e 2,10%, respectivamente. Foi observada redução do número efetivo de animais, especialmente após a publicação dos resultados do primeiro teste de progênie. O número efetivo de fundadores estimado foi de 146 e o de ancestrais, 75. Desses, apenas 28 ancestrais foram responsáveis pela origem de 50% dos genes da população. O intervalo médio de gerações foi 8,41 anos e foi maior para machos que para fêmeas. Para manutenção da variabilidade genética em futuras gerações, deve-se investir em estratégias de acasalamento que reduzam a endogamia e que não façam uso maciço de apenas alguns reprodutores de alto valor genético.

Natives ducks are birds that require little handling and are resistant to many diseases that affect chickens. Thus, they adapt to low-input farming conditions, which contributes to the food security of small farmers. Although they exhibit potential for growth, their production characteristics are relatively unknown, so they are underexploited. The objective of this study was to compare how nonlinear models fit the growth curve of two genetic groups of duck and to evaluate variation based on carcass characteristics. Two hundred and twenty four animals were weighed weekly, from birth to 90 days of age. We used nonlinear models (Brody, Richards, Gompertz, Von Bertalanff and Logistic) to describe growth curve. For the evaluation of phenotypic variation, we measured seven carcass traits from 81 ducks carried out by principal component analysis. The logistic model best fit the growth curve, and the absolute growth rates (AGR) for the Catolé duck showed that females reached their maximum AGR at approximately 30 days but did not reach their ideal commercial weight. The drumstick, thigh and liver yields accounted for 41.17% of the differences between the Catolé and Paysandu ducks. The slaughter of male Catolé ducks is recommended between 70 and 90 days because a drastic decrease in growth occurs after this time. For the slaughter of females, feeding management modifications and improvement in growth indices are recommended to increase the final weight and AGR. The carcass yields indicate potential for native duck meat production.

Carcass and ham quality characteristics of pig populations divided by harvest weights — HW (130 and 160 kg) were evaluated to determine the effects of gender (barrows and gilts) and distinct genetic groups — purebred (DUDU) and crossbred Duroc (DULA, DUWI and DULL) as well as purebred Large White (WIWI) on the suitability for use in dry-cured ham production. At 130 kg, DUDU pigs yielded the highest fat thickness of the ham (P < 0.01) and an intramuscular fat content (IMF) of 3.15% in Semimembranosus muscle (SM). DUDU pigs also had a SM pHu of 5.7. This genetic group met the specifications for dry-cured ham production. No differences could be found in meat quality characteristics between genetic groups harvested at 160 kg. However at this HW, gilts produced significantly (P < 0.05) heavier and leaner hams compared to barrows.

Objetivou-se estudar a variabilidade genética a curto prazo de características quantitativas simuladas a partir de modelos com ação gênica aditiva e não-aditiva em populações controle e de seleção fenotípica. As duas características, uma de baixa (h2 = 0,10) e outra de alta (h2 = 0,60) herdabilidade, foram controladas por 600 locos bialélicos. A partir de um genoma-padrão, foram obtidos seis modelos genéticos que incluíram: apenas efeitos aditivos dos genes; dominância completa e positiva para 25, 50, 75 e 100% dos locos; e sobredominância positiva para 50% dos locos. Nos modelos com desvio da dominância também foram incluídos os efeitos aditivos dos alelos para 100% dos locos. A variabilidade genética foi quantificada de geração a geração por meio de componentes de variância genética. Na ausência de seleção, as variâncias genotípica e genética aditiva mantiveram-se mais elevadas. Nos modelos com ação gênica não-aditiva, surgiu um componente de covariância entre os efeitos genéticos aditivos e de dominância de pequena magnitude e cuja correlação tendeu a ser positiva na população controle e negativa sob seleção. A variância de dominância aumentou com o acréscimo no número de locos com desvio da dominância ou no valor do desvio, o que implicou aumento das variâncias genotípica e genética aditiva entre os sucessivos modelos. The aim of this work was to investigate the short-term behavior of the genetic variability of quantitative traits simulated from models with additive and non-additive gene action in control and phenotypic selection populations. Both traits, one with low (h2 = 0.10) and the other with high (h2 = 0.60) heritability, were controlled by 600 biallelic loci. From a standard genome, it was obtained six genetic models which included the following: only the additive gene effects; complete and positive dominance for 25, 50, 75 and 100% of the loci; and positive overdominance for 50% of the loci. In the models with dominance deviation, the additive allelic effects were also included for 100% of the loci. Genetic variability was quantified from generation to generation using the genetic variance components. In the absence of selection, genotypic and additive genetic variances were higher. In the models with non-additive gene action, a small magnitude covariance component raised between the additive and dominance genetic effects whose correlation tended to be positive on the control population and negative under selection. Dominance variance increased as the number of loci with dominance deviation or the value of the deviation increased, implying on the increase in genotypic and additive genetic variances among the successive models.

Com o intuito de fornecer subsídios para programas de conservação, seleção e expansão da raça Gir no Nordeste do Brasil, objetivou-se avaliar o histórico do rebanho Gir registrado no nordeste brasileiro, com base na sua estrutura populacional e no progresso genético e fenotípico de características de desenvolvimento ponderal. Foram utilizadas informações de pedigree de animais nascidos no período de 1964 a 2006 e dados dos pesos ajustados aos 205 e 365 dias de idade de bovinos nascidos de 1978 a 2006. O progresso genético para a raça no Nordeste foi ocasionado exclusivamente pelo melhoramento ambiental. O tamanho efetivo da população reduziu a partir da década de 90, e o coeficiente de endogamia médio aumentou durante o período estudado. É imprescindível que o tamanho efetivo da raça Gir do nordeste seja ampliado e que haja maior controle de acasalamentos entre indivíduos aparentados, para prevenção da endogamia e conservação da variabilidade genética e viabilidade da raça. This paper provides an evaluation of the population structure, phenotype and genetic trends of registered Gyr herd cattle in northeast Brazil. The study provides important baseline information for the management, conservation and potential population expansion of this economically and culturally important cattle breed. Pedigree data were analyzed for individuals born between 1964 and 2006. Body weight values were adjusted to 205 and 365 days of age for animals born between 1978 and 2006. Phenotypic change of zebu Gyr in northeast Brazil is solely due to environmental improvement. However, there is potential for artificial selection for weight gain in young cattle. Effective population size decreased during the 1990s and the average inbreeding coefficient increased during the studied period. An increase of the effective population size of Gyr in northeast Brazil is strongly recommended, along with an increase in the management of the mating process to prevent inbreeding and to maintain the genetic variability of the breed.

The goal of the present work was to analyze the Brody, Von Bertalanffy, Richards, Logistic and Gompertz functions in order to describe the growth in crossbred sheep Dorper × Morada Nova (DMN), Dorper × Rabo Largo (DRL) and Dorper × Santa Ines (DSI). After defining the best adjusted model, the absolute growth rate was calculated and the influence of both environmental and genetic features on curve parameters was evaluated. The data were based on 156 F1 animals (36 DMN, 61 DRL and 59 DSI), weighed quarterly from birth up to 210 days of age. Both Gompertz and Logistic functions presented the best adjustment, being the latter slightly superior. The mature weight was statistically similar among the three genetic groups. However, the DSI group presented a faster growth during the pre-weaning period, with a remarkable fall from the inflection point on. The weight gain within such group was lower to those from DRL and DMN groups from 150 days of age on. Only the birth month has significantly influenced the asymptotic weight (A). The growth rate (k) was affected by birth month, type of parturition, sex, genetic group and parturition type vs. genetic group interaction. The estimated correlation between the parameters A and k were negative (−0.58 for DMN, −0.39 for DSI and −0.38 for DRL), indicating that more precocious animals are less likely to reach higher weights when adults.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:47:01Z No. of bitstreams: 1 S0100-204X2008000200009.pdf: 106377 bytes, checksum: 0852d027e7973d7b073303a82e40ab28 (MD5) Made available in DSpace on 2013-08-22T18:47:01Z (GMT). No. of bitstreams: 1 S0100-204X2008000200009.pdf: 106377 bytes, checksum: 0852d027e7973d7b073303a82e40ab28 (MD5) Previous issue date: 2008-02-01 Made available in DSpace on 2013-09-30T18:27:59Z (GMT). No. of bitstreams: 2 S0100-204X2008000200009.pdf: 106377 bytes, checksum: 0852d027e7973d7b073303a82e40ab28 (MD5) S0100-204X2008000200009.pdf.txt: 25803 bytes, checksum: e53dbd6960fd2e257e70247bdc5a962e (MD5) Previous issue date: 2008-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:41:23Z No. of bitstreams: 2 S0100-204X2008000200009.pdf: 106377 bytes, checksum: 0852d027e7973d7b073303a82e40ab28 (MD5) S0100-204X2008000200009.pdf.txt: 25803 bytes, checksum: e53dbd6960fd2e257e70247bdc5a962e (MD5) Made available in DSpace on 2014-05-20T13:41:23Z (GMT). No. of bitstreams: 2 S0100-204X2008000200009.pdf: 106377 bytes, checksum: 0852d027e7973d7b073303a82e40ab28 (MD5) S0100-204X2008000200009.pdf.txt: 25803 bytes, checksum: e53dbd6960fd2e257e70247bdc5a962e (MD5) Previous issue date: 2008-02-01 O objetivo deste trabalho foi avaliar a estrutura populacional e os progressos genéticos, fenotípicos e ambientais de características de desenvolvimento ponderal, em bubalinos da raça Mediterrâneo. Foram utilizadas informações dos pesos ajustados aos 205, 365 e 550 dias de idade, de 6.243 bubalinos nascidos no período de 1974 a 2003, provenientes de quatro fazendas. As estimativas dos coeficientes de herdabilidade foram altas para os pesos ajustados nas três idades. Os rebanhos apresentaram ganho genético positivo quanto a essas três características, porém, aquém do possível, provavelmente em razão da seleção baseada somente no fenótipo, realizada pelos produtores. Para aumento nos ganhos genéticos, são necessários a redução do intervalo de geração, o aumento do tamanho efetivo, o uso de reprodutores avaliados com base nos valores genéticos preditos pelo BLUP e o controle dos acasalamentos de animais aparentados. The objective of this work was to evaluate the population structure as well as the improvement of genetic, phenotypic, and environmental effects on growth development of Mediterranean water buffaloes, raised in Brazil. Information on weight adjusted at 205, 365, and 550 days of age of 6,243 buffaloes from four farms, which were born between 1974 and 2003, were used. Heritability coefficients for weight were high at the three ages. The herds presented a positive genetic gain in the three analyzed traits, although lower than expected, what was likely to be caused by empirical phenotype-based selection used by the local breeders. In order to improve genetic gains, it is necessary to decrease the generation interval, to increase the effective size, to use reproducers whose genetic values have been previously evaluated by BLUP, and to avoid mating between related animals. Universidade Estadual do Sudoeste da Bahia Departamento de Ciências Biológicas Universidade Estadual Paulista Faculdade de Medicina Veterinária e Zootecnia Departamento de Produção e Exploração Animal Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Meio-Norte Unidade de Execução de Pesquisas de Parnaíba Universidade para o Desenvolvimento do Estado e da Região do Pantanal Campus I Miguel Couto Universidade Federal de Uberlândia (UFU) Campus de Palotina Universidade Estadual Paulista Faculdade de Medicina Veterinária e Zootecnia Departamento de Produção e Exploração Animal

O objetivo deste trabalho foi comparar o desenvolvimento ponderal, por meio de curva de crescimento e pesos ajustados e avaliar a diversidade entre ovinos cruzados Dorper com as raças locais, com base em características de carcaça e morfológicas. Foram realizadas pesagens dos animais cruzados em intervalos de aproximadamente 15 dias e avaliados os efeitos de sexo, ano e grupo genético. Na estimativa dos parâmetros das curvas, foi utilizado o modelo não-linear Logístico e, a fim de avaliar o grau de similaridade entre os animais dos grupos genéticos, foram utilizadas variáveis canônicas. O sexo dos animais não influenciou o peso. Houve efeito de ano e grupo genético sobre o desenvolvimento dos animais. Conforme o modelo Logístico para a curva de crescimento, o grupo genético Dorper x Santa Inês apresentou maior velocidade de crescimento, estimado pelo peso à maturidade e taxa de maturação, seguido dos grupos genéticos Dorper x Morada Nova e Dorper x Rabo Largo. A análise de agrupamento ressaltou as diferenças entre os grupos genéticos e alocou os três cruzamentos em dois grupos, um formado pelos cruzamentos Dorper x Morada Nova e Dorper x Rabo Largo e o outro pelo cruzamento Dorper x Santa Inês. The goal of this work was to compare growth rate, by mean of growth and adjusted weight curves, and to analyze the diversity among crosses of Dorper ovines and local breeds, based on morphological and carcass features. Crossed animals were weighed in a 15-day-interval and the effects of sex, year and genetic group were analyzed. The non-linear Logistic model was used to estimate curve parameters and the degree of similarity among genetic groups was evaluated through canonic variables. Sex did not influence significantly on weight. There was a significant effect related to year and genetic group over animal's development. The estimates of growth curve based on parameters from the Logistic model indicated that the genetic group Dorper x Santa Inês presented a faster growth rate, as estimated by weight at maturity and maturity rate, followed by the genetic groups Dorper x Morada Nova and Dorper x Rabo Largo. Clustering analysis reinforced the differences among genetic groups, placing the three crosses in two groups, one comprising Dorper x Morada Nova and Dorper x Rabo Largo, and another including the cross Dorper x Santa Inês.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:03Z No. of bitstreams: 1 S1516-35982007000200014.pdf: 250349 bytes, checksum: 9fc42e4f0f0646b680d1dffabb936bfe (MD5) Made available in DSpace on 2013-08-22T19:07:03Z (GMT). No. of bitstreams: 1 S1516-35982007000200014.pdf: 250349 bytes, checksum: 9fc42e4f0f0646b680d1dffabb936bfe (MD5) Previous issue date: 2007-04-01 Made available in DSpace on 2013-09-30T20:11:30Z (GMT). No. of bitstreams: 2 S1516-35982007000200014.pdf: 250349 bytes, checksum: 9fc42e4f0f0646b680d1dffabb936bfe (MD5) S1516-35982007000200014.pdf.txt: 17297 bytes, checksum: 863bd05e60cc36c54e780401486b12b2 (MD5) Previous issue date: 2007-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:18:10Z No. of bitstreams: 2 S1516-35982007000200014.pdf: 250349 bytes, checksum: 9fc42e4f0f0646b680d1dffabb936bfe (MD5) S1516-35982007000200014.pdf.txt: 17297 bytes, checksum: 863bd05e60cc36c54e780401486b12b2 (MD5) Made available in DSpace on 2014-05-20T15:18:10Z (GMT). No. of bitstreams: 2 S1516-35982007000200014.pdf: 250349 bytes, checksum: 9fc42e4f0f0646b680d1dffabb936bfe (MD5) S1516-35982007000200014.pdf.txt: 17297 bytes, checksum: 863bd05e60cc36c54e780401486b12b2 (MD5) Previous issue date: 2007-04-01 Objetivou-se estimar os parâmetros e avaliar as tendências genética e fenotípica para a produção de leite ajustada aos 305 dias em bubalinos da raça Murrah nascidos no período de 1982 a 2003. Os parâmetros e os valores genéticos foram estimados por meio do aplicativo MTDFREML. A tendência genética foi estimada pela regressão dos valores genéticos sobre o ano de nascimento, por duas metodologias: 1) regressão linear; 2) regressão por meio de polinômios articulados utilizando-se a função de alisamento spline. A herdabilidade e a repetibilidade estimadas foram de 0,20 e 0,36, respectivamente. As tendências (regressão linear) fenotípica e genética foram significativas e iguais a 32,86 e 0,85 kg/ano, respectivamente. O ganho genético foi positivo, constatando-se instabilidade na tendência genética no decorrer dos anos, com períodos de ganhos e outros de perdas genéticas. A maior parte do ganho observado em alguns períodos resultou de melhorias nas condições ambientais. This study aimed to estimate genetic and phenotypic parameters and trends for adjusted 305 days milk yield of Murrah buffaloes, which were born from 1982 to 2003. Variance components, genetic parameters and breeding values were obtained using the MTDFREML program. Genetic trends were estimated by regression of breeding values on birth year of the animals by two methodologies: 1) linear regression and 2) articulated polynomial regression using a spline smoothing function. Heritability and repeatability estimates were 0.20 and 0.36, respectively. Phenotypic and genetic trends (by linear regression) were significant and equal to 32.86 and 0.85 kg/year, respectively. The genetic trend was positive but very unstable during the period. Most of the gain observed was due to environmental improvements. UESB Unesp DPEA UFPR Unesp DPEA

Leishmaniasis is an endemic disease present in 98 countries. In Brazil, the northeast region accounts for approximately half of the cases in humans, and has experienced an increased number of positive cases in dogs. In this study, we investigated the epidemiology of canine leishmaniasis in the city of Ilheus, Bahia, using serological and molecular techniques and evaluated the possible environmental risk factors and associated clinical signs. Blood samples were collected from 560 dogs in urban and peri-urban areas in Ilheus, northeastern Brazil. Genomic DNA was extracted from the selected animals and subjected to molecular analysis using Leishmania species-specific primers and diagnosis of Trypanosoma cruzi. A total of 54.72% of dogs were positive for Leishmania braziliensis, and animals positive for both Leishmania infantum and T. cruzi were not identified. Hematologic variables were not statistically associated with cases of L. braziliensis. However, the positive animal group showed lower red blood cell and platelet counts and higher levels of urea and serum creatinine. Few dogs presented clinical signs compatible with the presence of Leishmania. Age of more than 2 years and specific hair colors were associated with positive results for L. braziliensis. The geoclimatic characteristics of the region may improve parasite survival, reproduction, and vectors. This may explain the higher rate of dogs identified as positive in this study.

We evaluated the population genetic structure of the Holstein breed in Brazil through pedigree analysis with the aim of supporting genetic management of extant herds. We used data from genealogical records of 204,511 animals in farms from south and southeast Brazil. Pedigree records between 1943 and 2005 were divided into seven periods of 8 years to estimate the effective population size (N e ). N e varied during the study periods, ranging from 0.19 to 3016.25. There was an increase in the percentage of inbred animals over time, from 0.18 to 5.0 %. However, this figure may be an underestimate due to the low completeness of pedigree, primarily related to paternal pedigree. The effective number of founders (fe) was 473 animals and ancestors (fa) was 471. The genetic contribution of 260 ancestors (founders or not) accounted for 50 % of the genetic variability in the population. The average relatedness coefficient (AR) and inbreeding coefficient indicate that the Holstein breed in Brazil is being effectively managed, despite a moderate founder effect and the low number of animals that are responsible for the population variance.

Com o objetivo de avaliar o efeito da oscilação genética em populações sob seleção com diferentes tamanhos efetivos, foram simulados dados utilizando-se o programa GENESYS. A seleção foi praticada durante 20 gerações consecutivas, com base na seleção individual (SI) e nos valores genéticos preditos pelo BLUP Clássico (BLUP) e pelo BLUP Marcadores (BLUPM), com 30 repetições. A matriz de similaridade adotada no BLUP Marcadores foi obtida utilizando-se 100 marcadores moleculares do tipo microssatélite, por meio de um coeficiente de similaridade correspondente à distância euclidiana média para dados quantitativos. Foram simuladas seis populações de seleção, correspondendo a dois tamanhos efetivos (18,18 e 66,66) e três sistemas de acasalamento dos reprodutores selecionados (reprodutores acasalados ao acaso, exclusão de irmãos completos e exclusão de irmãos completos e meio-irmãos). O parâmetro avaliado foi o valor fenotípico médio. Observou-se grande variação nos valores fenotípicos obtidos pelos métodos, em razão da oscilação genética, principalmente para a seleção baseada nos valores genéticos preditos pelo BLUP e BLUPM e para as populações com tamanho efetivo menor (18,18). Os resultados sugerem que, em programas de melhoramento que utilizam pequenas populações sob seleção, os resultados podem ser influenciados pela oscilação genética, podendo apresentar grandes variações nos ganhos genéticos. The effect of genetic drift in populations under selection with different effective sizes was evaluated using data simulated by the GENESYS program. Selection was applied during 20 generations based on Individual selection (IS) using breeding values predicted by classical best linear unbiased prediction (BLUP) and BLUP associated with molecular markers (BLUPM). The similarity matrix used in BLUPM was obtained by simulation of 100 micro-satellites markers (simple sequence repeats) using a similarity coefficient corresponding to the mean Euclidean distance for quantitative data. Six populations of selection were simulated corresponding to two effective sizes (18.18 and 66.66), and three mating systems of selected sires (random mating, exclusion of half sibs and exclusion of half as well as full sibs). The average phenotypic value was the parameter of evaluation. Large variation on average phenotypic values was due to genetic drift, mainly for BLUP and BLUPM methods and also for populations with small effective sizes. The results indicate genetic drift may cause large variation in genetic gains by selection in breeding programs designed for small populations.