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Na pecuária de bovinos de corte, o temperamento mais dócil está ligado à facilidade de manejo e melhor qualidade da carne, e o escore composto de balança é método amplamente utilizado para a avaliação do temperamento. Na pesquisa sobre a qual versa este artigo, desenvolveu-se uma ferramenta de coleta de dados de movimentação de bovinos em ambiente de contenção, sobre a qual foram propostos e avaliados cálculos que representassem o temperamento quando comparado ao escore composto de balança. Para a ferramenta de coleta, utilizou-se um sensor acelerômetro capaz de monitorar movimentações em três dimensões. Após a análise das correlações entre os cálculos propostos e o escore composto de balança, concluiu-se que o cálculo envolvendo o somatório dos desvios padrão dos três eixos de movimentação é indicado para a avaliação de temperamento.

Este trabalho apresenta o algoritmo BrangusSelection, que produz um esquema ótimo de acasalamentos, maximizando o valor esperado da próxima geração do rebanho. Os testes com o algoritmo mostram um tempo de execução polinomial na quantidade de animais recebida como entrada, o que indica que o problema não é intratável computacionalmente. O algoritmo depende da existência de um índice de seleção, construído a partir dos objetivos e critérios de seleção dos animais e pode operar sobre qualquer espécie de animal e índice de seleção.

The aim of this study was to perform a Bayesian genomewide association study (GWAS) to identify genomic regions associated with growth traits in Hereford and Braford cattle, and to select Tag-SNPs to represent these regions in low-density panels useful for genomic predictions. In addition, we propose candidate genes through functional enrichment analysis associated with growth traits using Medical Subject Headings (MeSH). Phenotypic data from 126,290 animals and genotypes for 131 sires and 3,545 animals were used. The Tag-SNPs were selected with BayesB (π = 0.995) method to compose low-density panels. The number of Tag-single nucleotide polymorphism (SNP) ranged between 79 and 103 SNP for the growth traits at weaning and between 78 and 100 SNP for the yearling growth traits. The average proportion of variance explained by Tag-SNP with BayesA was 0.29, 0.23, 0.32 and 0.19 for birthweight (BW), weaning weight (WW205), yearling weight (YW550) and postweaning gain (PWG345), respectively. For Tag-SNP with BayesA method accuracy values ranged from 0.13 to 0.30 for k-means and from 0.30 to 0.65 for random clustering of animals to compose reference and validation groups. Although genomic prediction accuracies were higher with the full marker panel, predictions with low-density panels retained on average 76% of the accuracy obtained with BayesB with full markers for growth traits. The MeSH analysis was able to translate genomic information providing biological meanings of more specific gene products related to the growth traits. The proposed Tag-SNP panels may be useful for future fine mapping studies and for lower-cost commercial genomic prediction applications.

O trabalho apresenta a concepção de um modelo de sistema computacional escalável e distribuído, aplicado à gestão e qualificação de processos existentes na cadeia do leite. Baseado em uma arquitetura cloud-fog-thing, de baixo custo, instalados no sistema de ordenha, compostos por sensores e atuadores, capazes de se comunicar, com dispositivos móveis de capacidade intermediária presentes na camada fog, explorando mecanismos de comunicação veicular entre as diferentes camadas.

Our goal was to define a breeding objective for Brangus beef cattle in Brazil. Bioeconomic models were produced and used to estimate economic values (EVs). The scenarios simulated were typical full-cycle beef production systems that are used in tropical and subtropical regions. The breeding objective contained pregnancy rate (PR), warm carcass weight (WCW), mature cow weight (MCW), number of nematode eggs per gram of faeces (EPG) and tick count (TICK). Two models were used in series to estimate the EV. A deterministic model was used to simulate effects of PR, WCW and MCW on profitability with a constant parasite load. Subsequently, stochastic models were used to estimate economic values for TICK and EPG as consequences of their environmental effects on weight gains, mortality and health costs. The EV of PR, WCW, MCW, EPG and TICK, was US$1.59, US$2.11, -US$0.24, -US$5.35 and -US$20.88, respectively. Results indicate positive emphasis should be placed on PR (12.49%) and WCW (65.07%) with negative emphasis on MCW (13.92%), EPG (2.77%) and TICK (5.75%). In comparison with the indexes usually used, these results suggest a reformulation in the selection indexes of the beef production system in tropical and subtropical regions in order to obtain greater profitability.

The objective of the present study was to evaluate the accuracy and bias of direct and blended genomic predictions using different methods and cross-validation techniques for growth traits (weight and weight gains) and visual scores (conformation, precocity, muscling, and size) obtained at weaning and at yearling in Hereford and Braford breeds. Phenotypic data contained 126,290 animals belonging to the Delta G Connection genetic improvement program, and a set of 3,545 animals genotyped with the 50K chip and 131 sires with the 777K. After quality control, 41,045 markers remained for all animals. An animal model was used to estimate (co)variance components and to predict breeding values, which were later used to calculate the deregressed estimated breeding values (DEBV). Animals with genotype and phenotype for the traits studied were divided into 4 or 5 groups by random and k-means clustering cross-validation strategies. The values of accuracy of the direct genomic values (DGV) were moderate to high magnitude for at weaning and at yearling traits, ranging from 0.19 to 0.45 for the k-means and 0.23 to 0.78 for random clustering among all traits. The greatest gain in relation to the pedigree BLUP (PBLUP) was 9.5% with the BayesB method with both the k-means and the random clustering. Blended genomic value accuracies ranged from 0.19 to 0.56 for k-means and from 0.21 to 0.82 for random clustering. The analyses using the historical pedigree and phenotypes contributed additional information to calculate the GEBV, and in general, the largest gains were for the single-step (ssGBLUP) method in bivariate analyses with a mean increase of 43.00% among all traits measured at weaning and of 46.27% for those evaluated at yearling. The accuracy values for the marker effects estimation methods were lower for k-means clustering, indicating that the training set relationship to the selection candidates is a major factor affecting accuracy of genomic predictions. The gains in accuracy obtained with genomic blending methods, mainly ssGBLUP in bivariate analyses, indicate that genomic predictions should be used as a tool to improve genetic gains in relation to the traditional PBLUP selection.

The objectives of the present study were to investigate the influence of yearling weight on the occurrence of early pregnancy and to determine differences between precocious and non-precocious heifers in terms of pre- and postnatal calf mortality, calf weight and height, mature cow weight, and stayability of the cow in the herd. Data from 26 977 females of a Nelore herd that participated in the breeding season between 1986 and 2004 were analyzed. The influence of yearling weight on sexual precocity and differences between precocious and non-precocious heifers in pre- and postnatal calf mortality and stayability were analyzed using the GENMOD procedure of the SAS program. Differences in the growth traits between precocious and non-precocious animals were estimated by contrast analysis. Three groups were analyzed for postnatal mortality: first calving of the heifers, calves born from the third calving and all offspring of the cow. In order to have a standardized calving to conception period for all females (precocious and non-precocious), calves born from the second calving were not included in the analysis. This was necessary because the first calving to conception period (days open) of precocious heifers was longer than for non-precocious due to farm reproductive management. No differences in postnatal mortality rates, from the third calving, were observed between the two groups of heifers studied. Analysis of all offspring of the dams showed a 9% higher probability of death of calves born to precocious heifers compared with calves born to non-precocious heifers. With respect to stayability, precocious heifers presented 33% greater odds to remain in the herd until 5 and 6 years of age and 28% greater odds to remain in the herd until 7 years when compared with non-precocious heifers. Precocious heifers weaned calves (205 days) significantly heavier than non-precocious ones, 1.410 and 0.797 kg considering the weaning weights of all offspring and of the third calving, respectively. With respect to sexual precocity, the results suggest that the probability of heifers to become pregnant at 16 months of age increases with increasing weight. However, heifers weighing more than 240 kg present practically the same pregnancy probability. Nevertheless, exposure of heifers during the early breeding season is recommended for beef cattle herds raised in tropical regions in view of the numerous benefits demonstrated here.

The aim of this paper was to study the development of carcass traits obtained by ultrasound, weight, chest circumference and hip height by longitudinal data of two genetic groups of heifers. These data were analyzed by different structures of residual (co)variance consider homogeneity or heterogeneity of (co)variances to better represent the variability between and within individual observations over the time. The traits were obtained in 60 animals ½ Braunvieh x ¼ Santa Gertrudes x ¼ Nelore and 60 animals ½ Santa Gertrudes x ½ Nelore. The traits were evaluated at intervals of 28 days. The comparison was done with several models, based on the criterion SBC (Schwarz’s Bayesian Criterion) with the goal of identifying structures of residual (co)variance more appropriate to best represent the variation of the measures within individuals. Later, as the animals were measured at different ages, it was evaluated the most appropriate model to regress these traits as a function of age, using ordinary polynomials and verifying the need for different curves for each genetic group. The results indicated that it should consider different structures of residual (co)variance to better represent the variability between and within individualobservations. For weight, hip height, chest circumference and longissimus muscle area traits there are differences in the genetic group over the time.

Objetivou-se avaliar os efeitos das interações genótipo-ambiente sobre as estimativas de componentes de (co)variâncias e predição dos valores genéticos para o peso ao desmame de bovinos Nelore, sob enfoque bayesiano. Foram utilizados 16.644 registros de pesos ao desmame de bovinos provenientes de dez rebanhos participantes do Programa Nelore Brasil. Os parâmetros genéticos foram estimados sob modelo animal, considerando a estatística bayesiana. Para verificar o efeito da interação genótipo-ambiente, foram analisados os seguintes modelos matriciais: sem a inclusão dos efeitos de interação genótipo-ambiente; com a inclusão dos efeitos de interação genótipo-ambiente, em que se considerou o efeito de touro-ano, touro-rebanho e ambos os efeitos. De modo geral, verifica-se que a inclusão da interação genótipo-ambiente na análise genética para o peso ao desmame, tende a alterar as estimativas de (co)variâncias genéticas e ambientais. As correlações de Spearman entre os valores genéticos foram acima de 97%, indicando que, praticamente, não houve mudança na classificação dos animais avaliados. Pode se inferir que os efeitos de interação touro-ano e touro-rebanho não alteram as classificações dos animais, e a não-inclusão destes efeitos na avaliação genética, não afetam a seleção baseada nas predições dos valores genéticos para o peso ao desmame.The objective was to evaluate the interactions of genotype-environment effects on the components of (co)variance estimates and the prediction of breeding values for weaning weight in Nelore cattle, using a Bayesian approach. Records of 16,644 weaning weights were used from cattle distributed in ten ranches across six Brazilian states. The genetic parameters were estimated under an animal model considering Bayesian statistics. To verify genotype-environment interaction effects, we analyzed the following matrix model: without the inclusion of genotype-environment interaction effects, and with the inclusion of genotype-environment interaction effects, which considered the effect of sire-year, sire-herd, and both effects. In general, the results suggest that the inclusion of genotype-environment interaction in genetic analysis for weight at weaning tends to alter the estimates of genetic and environment (co)variances. The Spearman correlations between the breeding values were above 97%, indicating practically no change in the classification of animals evaluated. It can be inferred that the interaction effects of sire-year and sire-herd do not change the animals rank, and if not included in the genetic evaluation, the selection based on predictions of breeding values for weaning weight will not be affected.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:37Z No. of bitstreams: 1 S1516-35982010000500030.pdf: 293253 bytes, checksum: 76dd9278263c711bbb33bd9b3460ccd2 (MD5) Made available in DSpace on 2013-08-22T19:07:37Z (GMT). No. of bitstreams: 1 S1516-35982010000500030.pdf: 293253 bytes, checksum: 76dd9278263c711bbb33bd9b3460ccd2 (MD5) Previous issue date: 2010-05-01 Made available in DSpace on 2013-09-30T20:12:12Z (GMT). No. of bitstreams: 2 S1516-35982010000500030.pdf: 293253 bytes, checksum: 76dd9278263c711bbb33bd9b3460ccd2 (MD5) S1516-35982010000500030.pdf.txt: 30012 bytes, checksum: 12f0e8b970c31dfebf2be3610d3d8b17 (MD5) Previous issue date: 2010-05-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:28:38Z No. of bitstreams: 2 S1516-35982010000500030.pdf: 293253 bytes, checksum: 76dd9278263c711bbb33bd9b3460ccd2 (MD5) S1516-35982010000500030.pdf.txt: 30012 bytes, checksum: 12f0e8b970c31dfebf2be3610d3d8b17 (MD5) Made available in DSpace on 2014-05-20T13:28:38Z (GMT). No. of bitstreams: 2 S1516-35982010000500030.pdf: 293253 bytes, checksum: 76dd9278263c711bbb33bd9b3460ccd2 (MD5) S1516-35982010000500030.pdf.txt: 30012 bytes, checksum: 12f0e8b970c31dfebf2be3610d3d8b17 (MD5) Previous issue date: 2010-05-01 Objetivou-se estudar as medidas de espessura de gordura subcutânea, área de olho-de-lombo, comprimento e profundidade máxima do músculo longissimus dorsi entre a 13ª costela e 1ª vértebra lombar determinadas por ultrassom e na carcaça de ovelhas de descarte abatidas em diferentes estágios fisiológicos, além dos coeficientes de correlação e determinação das medidas avaliadas. Utilizaram-se 21 ovelhas da raça Santa Inês, distribuídas nos seguintes grupos: OL = ovelhas que permaneceram por 60 dias em lactação com seus cordeiros e foram abatidas um dia após o desmame dos mesmos; OSC = ovelhas que permaneceram por 60 dias em lactação com seus cordeiros e mais 30 dias sem os cordeiros e foram posteriormente abatidas; e ONP = ovelhas que não pariram durante o ano. O comprimento máximo do músculo longissimus dorsi obtido pelo ultrassom e na carcaça dos animais não foi influenciado pelos estágios fisiológicos. O ultrassom pode ser utilizado com razoável precisão para estimar características da carcaça de ovelhas de descarte, em particular a espessura de gordura subcutânea. The objective of this paper was to study subcutaneous fat thickness, loin eye area, length and maximum depth measurements of the longissimus dorsi muscle between the 13th rib and the 1st lumbar vertebra determined by ultrasound examination and on the carcass of discard ewes slaughtered in different physiological stages, besides correlation and determination coefficients among measurements evaluated. It was used 21 Santa Ines ewes distributed into the following treatments: EL = ewes that remained in lactation for 60 days with their respective lambs and slaughtered one day after weaning; EWL = ewes that remained in lactation for 60 days with their respective lambs one more period of approximately 30 days without the lambs and slaughtered afterwards; and ENC = ewes that did not give birth during the year. Results showed that the maximum length of the longissimus dorsi muscle obtained by ultrasound examination and on carcass of the animals were not influenced by the experimental treatments. The ultrasound can be used with reasonable accuracy to estimate characteristics of the carcass of discard ewes, particularly the thickness of subcutaneous fat. Unesp FEIS DBZ Unesp FMVZ DPA Unesp FCAV Unesp FEIS DBZ Unesp FMVZ DPA Unesp FCAV

The aim of the present study was to evaluate the genetic correlations among real-time ul- trasound carcass, BW, and scrotal circumference (SC) traits in Nelore cattle. Carcass traits, measured by real- time ultrasound of the live animal, were recorded from 2002 to 2004 on 10 farms across 6 Brazilian states on 2,590 males and females ranging in age from 450 to 599 d. Ultrasound records of LM area (LMA) and backfat thickness (BF) were obtained from cross-sectional im- ages between the 12th and 13th ribs, and rump fat thickness (RF) was measured between the hook and pin bones over the junction between gluteus medius and bi- ceps femoris muscles. Also, BW (n = 22,778) and SC (n = 5,695) were recorded on animals born between 1998 and 2003. The BW traits were 120, 210, 365, 450, and 550-d standardized BW (W120, W210, W365, W450, and W550), plus BW (WS) and hip height (HH) on the ultrasound scanning date. The SC traits were 365-, 450-, and 550-d standardized SC (SC365, SC450, and SC550). For the BW and SC traits, the database used was from the Nelore Breeding Program—Nelore Bra- zil. The genetic parameters were estimated with mul- tivariate animal models and REML. Estimated genetic correlations between LMA and other traits were 0.06 (BF), −0.04 (RF), 0.05 (HH), 0.58 (WS), 0.53 (W120), 0.62 (W210), 0.67 (W365), 0.64 (W450 and W550), 0.28 (SC365), 0.24 (SC450), and 0.00 (SC550). Esti- mated genetic correlations between BF and with other traits were 0.74 (RF), −0.32 (HH), 0.19 (WS), −0.03 (W120), −0.10 (W210), 0.04 (W365), 0.01 (W450), 0.06 (W550), 0.17 (SC365 and SC450), and −0.19 (SC550). Estimated genetic correlations between RF and other traits were −0.41 (HH), −0.09 (WS), −0.13 (W120), −0.09 (W210), −0.01 (W365), 0.02 (W450), 0.03 (W550), 0.05 (SC365), 0.11 (SC450), and −0.18 (SC550). These estimates indicate that selection for carcass traits measured by real-time ultrasound should not cause antagonism in the genetic improvement of SC and BW traits. Also, selection to increase HH might de- crease subcutaneous fat as correlated response. There- fore, to obtain animals suited to specific tropical pro- duction systems, carcass, BW, and SC traits should be considered in selection programs.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:47:05Z No. of bitstreams: 1 S0100-204X2009000200012.pdf: 285057 bytes, checksum: f8e986731d79662a412f6b08f746456a (MD5) Made available in DSpace on 2013-08-22T18:47:05Z (GMT). No. of bitstreams: 1 S0100-204X2009000200012.pdf: 285057 bytes, checksum: f8e986731d79662a412f6b08f746456a (MD5) Previous issue date: 2009-02-01 Made available in DSpace on 2013-09-30T18:02:50Z (GMT). No. of bitstreams: 2 S0100-204X2009000200012.pdf: 285057 bytes, checksum: f8e986731d79662a412f6b08f746456a (MD5) S0100-204X2009000200012.pdf.txt: 29968 bytes, checksum: cfc0308ede81a81cf8d1df1e14078dc1 (MD5) Previous issue date: 2009-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:18:57Z No. of bitstreams: 2 S0100-204X2009000200012.pdf: 285057 bytes, checksum: f8e986731d79662a412f6b08f746456a (MD5) S0100-204X2009000200012.pdf.txt: 29968 bytes, checksum: cfc0308ede81a81cf8d1df1e14078dc1 (MD5) Made available in DSpace on 2014-05-20T13:18:57Z (GMT). No. of bitstreams: 2 S0100-204X2009000200012.pdf: 285057 bytes, checksum: f8e986731d79662a412f6b08f746456a (MD5) S0100-204X2009000200012.pdf.txt: 29968 bytes, checksum: cfc0308ede81a81cf8d1df1e14078dc1 (MD5) Previous issue date: 2009-02-01 O objetivo deste trabalho foi estimar correlações genéticas e fenotípicas entre escores visuais e características de carcaça medidas por ultrassom, para verificar a eficácia desses escores na determinação da musculosidade e na avaliação da carcaça. As características de carcaça medidas por ultrassom foram área de olho de lombo (AOL) e espessura de gordura subcutânea (EG), mensuradas entre a região da 12ª e 13ª costelas, bem como a espessura de gordura subcutânea na garupa (EGP8). As características de estrutura (E), precocidade (P) e musculosidade (M) foram avaliadas por meio de escores visuais. Os componentes de covariância usados para estimar as correlações genéticas e fenotípicas foram obtidos pelo método da máxima verossimilhança restrita, em uma análise multicaracterística. As estimativas de correlações genéticas entre AOL e E, P e M foram 0,54, 0,58 e 0,61, respectivamente, e indicaram que, a longo prazo, a utilização da AOL como critério de seleção poderá produzir animais com maiores escores visuais para essas características. As correlações genéticas estimadas entre as espessuras de gordura (EG e EGP8) e os escores P e M apresentaram comportamento semelhante. Entretanto, as correlações genéticas entre as espessuras de gordura (EG e EGP8) e E foram próximas de zero. As correlações fenotípicas seguiram as mesmas tendências das respectivas correlações genéticas. Essas estimativas indicam que os escores visuais são determinados, em parte, pelos mesmos conjuntos de genes que influenciam a AOL. The aim of this work was to evaluate the genetic and phenotypic correlations between carcass traits measured by real-time ultrasound and by visual scores, in order to verify the effectiveness of these scores in determining muscularity and carcass fat. Carcass traits measured by real-time ultrasound were longissimus muscle area (LMA) and backfat thickness (BF), obtained between the 12th and 13th ribs, as well as the rump fat thickness (RF). The visual scores for the traits of body structure (E), precocity (P), and muscle (M) were evaluated individually. The genetic and phenotypic parameters were estimated by multivariate analysis, using restricted maximum likelihood methodology. The estimated genetic correlations between LMA and E, P and M were 0.54, 0.58 and 0.61, respectively, indicating that, in the long term, the use of LMA as a selection criterion might produce animals with higher visual scores. Similar genetic correlations were found between both subcutaneous fat measures (BF and RF) and P and M scores. However, genetic correlations between both subcutaneous fat measures and E were close to zero. The phenotypic correlations followed the same trends of their respective genetic correlations. These estimates indicate that the visual scores and LMA are, in part, determined by the same groups of genes. Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia Brasilcomz, Zootecnia Tropical University of California Department of Animal Science Associação Nacional de Criadores e Pesquisadores Aval Serviços Tecnológicos Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia

The aim of the present study was to evaluate the genetic and environmental factors affecting records of longissimus muscle area (LMA) and backfat thickness (BF) obtained between the 12th and 13th ribs, and rump fat thickness (RF) between the hook and pin bones, measured by real-time ultrasound in Nelore cattle. Also, weight records of 22,778 animals born from 1998 to 2003, in ten farms across six Brazilian states were used. Carcass traits as measured by ultrasound of the live animal were recorded from 2002 to 2004 in 2590 males and females with ages varying from 450 to 599 days. Fixed models including farm, year and season of birth, sex and type of feed effects, and the covariates age of dam (AOD) and age of animal at measurement were used to study the effect of environmental factors on these traits. The genetic parameters for LMA, BF and RF were estimated with two and three-trait animal models with 120-day weights using a restricted maximum likelihood method. All environmental effects significantly affected carcass traits, with the exception of year of birth for BF and RF and AOD for LMA. The heritability estimates for LMA, BF and RF were 0.35, 0.51 and 0.39, respectively. Standard errors obtained in one-trait analyses were from 0.07 to 0.09. Genetic correlation estimates between LMA and the two traits of subcutaneous fat were low (close to zero) and 0.74 between BF and RF, indicating that the selection for LMA should not cause antagonism in the genetic improvement of subcutaneous fat measured by real-time ultrasound.

Some measurements carried out by ultrasound in the Longissimus dorsi between the 12th and 13th ribs were monitored, aiming to know the changes in the muscular and adipose tissues in that muscle and the connections of these measurements with body weight (BW) and body condition score (BCS) of ewes in different stages (physiological stages and experimental periods). Ewes were arranged into the following treatments: EL = ewes which remained in lactation for 60 days with their respective lambs and slaughtered one day after weaning; EWL = ewes which remained in lactation for 60 days with their respective lambs and one more period of approximately 30 days without the lambs and slaughtered afterwards; and ENC = ewes which did not give birth during the year. Ultrasound measurements were carried out in the beginning, middle and end of the experiment (every 21 days), as well as BW and BCS of ewes. There was not interaction between periods and experimental treatments for BW and BCS of ewes. It was concluded that the use of ultrasound allows monitoring changes that occur with the subcutaneous fat and Longissimus dorsi of ewes. Those changes occur more frequently in intervals of 42 days (muscular and adipose tissues). Monitoraram-se algumas medidas realizadas no Longissimus dorsi entre a 12a e 13a costelas por ultrassom, com objetivo de conhecer as mudanças que ocorrem com os tecidos muscular e adiposo neste músculo e a relação destas medidas com o peso corporal (PC) e com o escore de condição corporal (ECC) de ovelhas em diferentes fases (estágios fisiológicos e períodos experimentais). As ovelhas foram distribuídas nos respectivos tratamentos: OL = ovelhas que permaneceram por 60 dias em lactação com seus respectivos cordeiros e abatidas um dia após o desmame dos mesmos; OSC = ovelhas que permaneceram por 60 dias em lactação com seus respectivos cordeiros e mais um período de 30 dias sem os cordeiros e posteriormente foram abatidas; ONP = ovelhas que não pariram durante o ano. As medidas por ultrassom foram realizadas no início, no meio e no fim do trabalho (períodos experimentais de 21 dias cada), assim como o PC e a ECC das ovelhas. Não houve interação entre os períodos e tratamentos experimentais para o PC e para a ECC das ovelhas. Concluiu-se que a utilização do ultrassom permite monitorar as mudanças que ocorrem com a gordura subcutânea e com o Longissimus dorsi de ovelhas. Mudanças estas que ocorrem com uma frequência maior em intervalos de 42 dias entre avaliações dos tecidos muscular e adiposo.

Made available in DSpace on 2016-07-07T12:33:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2014. Added 1 bitstream(s) on 2016-07-07T12:42:54Z : No. of bitstreams: 1 ISSN1679-0359-2014-35-04-2739-2748.pdf: 655153 bytes, checksum: edb3aa77facd6b3b35a242e45f6a541d (MD5) Monitoraram-se algumas medidas realizadas no Longissimus dorsi entre a 12a e 13a costelas por ultrassom, com objetivo de conhecer as mudanças que ocorrem com os tecidos muscular e adiposo neste músculo e a relação destas medidas com o peso corporal (PC) e com o escore de condição corporal (ECC) de ovelhas em diferentes fases (estágios fisiológicos e períodos experimentais). As ovelhas foram distribuídas nos respectivos tratamentos: OL = ovelhas que permaneceram por 60 dias em lactação com seus respectivos cordeiros e abatidas um dia após o desmame dos mesmos; OSC = ovelhas que permaneceram por 60 dias em lactação com seus respectivos cordeiros e mais um período de 30 dias sem os cordeiros e posteriormente foram abatidas; ONP = ovelhas que não pariram durante o ano. As medidas por ultrassom foram realizadas no início, no meio e no fim do trabalho (períodos experimentais de 21 dias cada), assim como o PC e a ECC das ovelhas. Não houve interação entre os períodos e tratamentos experimentais para o PC e para a ECC das ovelhas. Concluiu-se que a utilização do ultrassom permite monitorar as mudanças que ocorrem com a gordura subcutânea e com o Longissimus dorsi de ovelhas. Mudanças estas que ocorrem com uma frequência maior em intervalos de 42 dias entre avaliações dos tecidos muscular e adiposo. Some measurements carried out by ultrasound in the Longissimus dorsi between the 12th and 13th ribs were monitored, aiming to know the changes in the muscular and adipose tissues in that muscle and the connections of these measurements with body weight (BW) and body condition score (BCS) of ewes in different stages (physiological stages and experimental periods). Ewes were arranged into the following treatments: EL = ewes which remained in lactation for 60 days with their respective lambs and slaughtered one day after weaning; EWL = ewes which remained in lactation for 60 days with their respective lambs and one more period of approximately 30 days without the lambs and slaughtered afterwards; and ENC = ewes which did not give birth during the year. Ultrasound measurements were carried out in the beginning, middle and end of the experiment (every 21 days), as well as BW and BCS of ewes. There was not interaction between periods and experimental treatments for BW and BCS of ewes. It was concluded that the use of ultrasound allows monitoring changes that occur with the subcutaneous fat and Longissimus dorsi of ewes. Those changes occur more frequently in intervals of 42 days (muscular and adipose tissues). Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Faculdade de Engenharia (FEIS), Departamento de Biologia e Zootecnia, Ilha Solteira, SP, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Faculdade de Medicina Veterinária e Zootecnia (FMVZ), Departamento de Produção Animal, Botucatu, SP, Brasil Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Centro de Pesquisa de Pecuária dos Campos Sul-Brasileiros (CPPSUL), Bagé, RS, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Produção Animal, Faculdade de Medicina Veterinária e Zootecnia de Botucatu, Botucatu, Depto. Produção Animal, Lageado, CEP 18618-000, SP, Brasil

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:47:07Z No. of bitstreams: 1 S0100-204X2010000600011.pdf: 431120 bytes, checksum: 5e57cec7e6dc8f3d3b9cc2cd9f692d8b (MD5) Made available in DSpace on 2013-08-22T18:47:07Z (GMT). No. of bitstreams: 1 S0100-204X2010000600011.pdf: 431120 bytes, checksum: 5e57cec7e6dc8f3d3b9cc2cd9f692d8b (MD5) Previous issue date: 2010-06-01 Made available in DSpace on 2013-09-30T18:02:00Z (GMT). No. of bitstreams: 2 S0100-204X2010000600011.pdf: 431120 bytes, checksum: 5e57cec7e6dc8f3d3b9cc2cd9f692d8b (MD5) S0100-204X2010000600011.pdf.txt: 34346 bytes, checksum: d620a6fadba23e9d6dff3d36c10fb7e6 (MD5) Previous issue date: 2010-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:18:42Z No. of bitstreams: 2 S0100-204X2010000600011.pdf: 431120 bytes, checksum: 5e57cec7e6dc8f3d3b9cc2cd9f692d8b (MD5) S0100-204X2010000600011.pdf.txt: 34346 bytes, checksum: d620a6fadba23e9d6dff3d36c10fb7e6 (MD5) Made available in DSpace on 2014-05-20T13:18:42Z (GMT). No. of bitstreams: 2 S0100-204X2010000600011.pdf: 431120 bytes, checksum: 5e57cec7e6dc8f3d3b9cc2cd9f692d8b (MD5) S0100-204X2010000600011.pdf.txt: 34346 bytes, checksum: d620a6fadba23e9d6dff3d36c10fb7e6 (MD5) Previous issue date: 2010-06-01 O objetivo deste trabalho foi determinar os fatores que afetam a altura da garupa em diferentes idades, em bovinos Nelore, e estimar a herdabilidade e as correlações genéticas entre esse caractere e as características reprodutivas e de crescimento. Os caracteres avaliados foram: altura da garupa à desmama, altura da garupa ao sobreano, peso à desmama, peso ao sobreano, perímetro escrotal e idade ao primeiro parto. Os fatores considerados foram: ano e mês de nascimento, rebanho, sexo, idade da vaca ao parto e idade do bezerro. Os componentes de variância e covariância foram estimados pela metodologia de máxima verossimilhança restrita, tendo-se utilizado um modelo animal. Todos os efeitos foram significativos para altura de garupa nas diferentes idades. As estimativas de herdabilidade quanto ao efeito genético direto indicaram que as características de crescimento e reprodutivas respondem à seleção, exceto a idade ao primeiro parto. As correlações genéticas entre as características de crescimento foram todas positivas e elevadas, de 0,42 a 0,90, o que indica que são determinadas em grande parte pelos mesmos conjuntos de genes de ação aditiva. em razão das baixas magnitudes das estimativas de correlação genética (entre -0,14 e 0,16), a eficiência reprodutiva é pouco influenciada pela seleção quanto à altura de garupa. The objective of this work was to determine factors that affect hip height at different ages, in Nelore cattle, and to estimate the heritability and the genetic correlation between this character and reproductive and growth traits. The analyzed traits were: hip height at weaning, hip height at post weaning, weight at weaning, weight at post weaning, scrotal circumference, and age at first calving. The analyzed factors were: year and month of birth, herd, sex, age of dam at calving, and calf age. The variance covariance components were estimate by the restrict maximum likelihood methodology using animal model. All effects were significant for hip height at different ages. The heritability estimates for direct genetic effects indicated that the growth and reproductive traits respond to selection, except for age at first calving. The genetic correlations between growth traits were positive and high, from 0.42 to 0.90, which indicates that they are mostly determined by the same group of genes with additive action. Due to the low magnitude of the estimated genetic correlations, from -0.14 to 0.16, the reproductive efficiency is little influenced by selection for hip height. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Gado de Leite Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia Agropecuária Jacarezinho Ltda. Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Departamento de Zootecnia

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:36Z No. of bitstreams: 1 S1516-35982010000500011.pdf: 124306 bytes, checksum: 3998c8f858f088a97053d22329150b31 (MD5) Made available in DSpace on 2013-08-22T19:07:36Z (GMT). No. of bitstreams: 1 S1516-35982010000500011.pdf: 124306 bytes, checksum: 3998c8f858f088a97053d22329150b31 (MD5) Previous issue date: 2010-05-01 Made available in DSpace on 2013-09-30T18:03:21Z (GMT). No. of bitstreams: 2 S1516-35982010000500011.pdf: 124306 bytes, checksum: 3998c8f858f088a97053d22329150b31 (MD5) S1516-35982010000500011.pdf.txt: 38757 bytes, checksum: 2c84cde74538f2252d1bfc1e4ad298b9 (MD5) Previous issue date: 2010-05-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:19:07Z No. of bitstreams: 2 S1516-35982010000500011.pdf: 124306 bytes, checksum: 3998c8f858f088a97053d22329150b31 (MD5) S1516-35982010000500011.pdf.txt: 38757 bytes, checksum: 2c84cde74538f2252d1bfc1e4ad298b9 (MD5) Made available in DSpace on 2014-05-20T13:19:07Z (GMT). No. of bitstreams: 2 S1516-35982010000500011.pdf: 124306 bytes, checksum: 3998c8f858f088a97053d22329150b31 (MD5) S1516-35982010000500011.pdf.txt: 38757 bytes, checksum: 2c84cde74538f2252d1bfc1e4ad298b9 (MD5) Previous issue date: 2010-05-01 Foram avaliados 27.523 e 21.746 registros das características conformação, precocidade e musculatura à desmana e ao sobreano, respectivamente, para estimar os componentes de covariância entre estas características e entre estas e os pesos corporais medidos nas mesmas idades. Para as análises dos dados, foram empregados modelos animais com efeitos genéticos direto e materno e efeito de ambiente permanente materno. Máxima verossimilhança restrita foi empregada para estimar os parâmetros genéticos. As estimativas de herdabilidade dos escores à desmama foram 0,13; 0,25 e 0,23 para conformação, precocidade e musculatura, respectivamente. As estimativas de herdabilidade dos escores visuais avaliados ao sobreano foram de maiores magnitudes (0,24; 0,32 e 0,27 para conformação, precocidade e musculatura, respectivamente). As estimativas das correlações genéticas entre escores medidos às mesmas idades, considerando desmana e sobreano, foram 0,67 e 0,75 entre conformação e precocidade; 0,61 e 0,71 entre conformação e musculatura; 0,95 e 0,95 entre precocidade e musculatura. As correlações genéticas estimadas entre o peso corporal à desmama e conformação, precocidade e musculatura, respectivamente, foram 0,97; 0,67 e 0, 62. As estimativas entre conformação, precocidade, musculatura ao sobreano e o peso corporal foram 0,83; 0,59 e 0,58, respectivamente. Os resultados indicam que os escores visuais podem ser utilizados como critérios de seleção. Aumento nos pesos corporais deve ser esperado como resposta correlacionada à seleção para essas características. It was evaluated 27,523 and 21,746 records on traits of conformation, finishing precocity and musculature measured at weaning and a year after weaning, respectively, for the estimation of (co)variance components among these traits, and between them and body weights at the same ages. The data were analyzed by employing an animal model with direct and maternal genetic effect and permanent maternal environment effect. Restricted maximum likelihood was employed for the estimation of genetic parameters. The heritability estimates of visual scores at weaning were 0.13, 0.25, 0.23 for conformation, finishing precocity, and musculature respectively. The heritability estimates of visual scores one year after weaning were greater: 0.24, 0.32 and 0.27 for conformation, finishing precocity, and musculature, respectively. The genetic correlations estimates among scores at the same ages were: 0.67 and 0.75 between conformation and finishing precocity; 0.61 and 0.71 between conformation and musculature; 0.95 and 0.95 between finishing precocity and musculature, considering weaning and one year further, respectively. The genetic correlations estimated between weaning weight and conformation, finishing precocity, and musculature, were 0.97, 0.67 and 0.62, respectively. The estimates among conformation, finishing precocity, musculature at year after weaning and body weight were 0.83, 0.59, 0.58, respectively. The results indicated that the visual scores can be used as selection criteria. Body weight increases can be expected as a correlated response for selection of such traits. UNESP FCAV Programa de Pós-Graduação em Zootecnia BrasilComZ - Zootecnia Tropical UNESP FCAV Departamento de Zootecnia UNESP FCAV Programa de Pós-Graduação em Genética e Melhoramento Animal Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Pecuária Sudeste UNESP FCAV Programa de Pós-Graduação em Zootecnia UNESP FCAV Departamento de Zootecnia UNESP FCAV Programa de Pós-Graduação em Genética e Melhoramento Animal

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:35Z No. of bitstreams: 1 S1516-35982010000400008.pdf: 590639 bytes, checksum: bb3a42d72595bc6b2de8c9d5547f5c02 (MD5) Made available in DSpace on 2013-08-22T19:07:35Z (GMT). No. of bitstreams: 1 S1516-35982010000400008.pdf: 590639 bytes, checksum: bb3a42d72595bc6b2de8c9d5547f5c02 (MD5) Previous issue date: 2010-04-01 Made available in DSpace on 2013-09-30T20:12:09Z (GMT). No. of bitstreams: 2 S1516-35982010000400008.pdf: 590639 bytes, checksum: bb3a42d72595bc6b2de8c9d5547f5c02 (MD5) S1516-35982010000400008.pdf.txt: 24667 bytes, checksum: 3ad1940b923df2ceb6230a8f1060989a (MD5) Previous issue date: 2010-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:18:17Z No. of bitstreams: 2 S1516-35982010000400008.pdf: 590639 bytes, checksum: bb3a42d72595bc6b2de8c9d5547f5c02 (MD5) S1516-35982010000400008.pdf.txt: 24667 bytes, checksum: 3ad1940b923df2ceb6230a8f1060989a (MD5) Made available in DSpace on 2014-05-20T15:18:17Z (GMT). No. of bitstreams: 2 S1516-35982010000400008.pdf: 590639 bytes, checksum: bb3a42d72595bc6b2de8c9d5547f5c02 (MD5) S1516-35982010000400008.pdf.txt: 24667 bytes, checksum: 3ad1940b923df2ceb6230a8f1060989a (MD5) Previous issue date: 2010-04-01 Avaliou-se a repetibilidade da mensuração de imagens de ultrassom da área do músculo longissimus dorsi (AOL) e das espessuras de gordura subcutânea do lombo (EGL) e da garupa (EGG). Imagens de ultrassom tomadas no lombo (entre a 12ª e a 13ª costela) e na garupa (entre os músculos gluteus medium e biceps femoris) de novilhas Nelore de 14 a 22 meses de idade foram classificadas em aceitáveis, marginais e rejeitáveis. As imagens aceitáveis e marginais foram mensuradas duas vezes por três técnicos em diferentes níveis de treinamento. Foram estimadas as repetibilidades entre e dentro de técnicos por classe de qualidade da imagem, para determinação do efeito da qualidade da imagem e do técnico no valor absoluto da diferença entre a primeira e a segunda mensuração dessas características. A repetibilidade para as imagens aceitáveis foi maior que para imagens marginais, tanto entre como dentro de técnicos. Na análise da diferença absoluta entre a primeira e a segunda interpretação, foram significativos os efeitos de técnico para AOL e EGL e de classe de qualidade da imagem para AOL. em geral, o técnico com maior experiência apresentou maiores valores de repetibilidade. É recomendável que a mensuração de imagens de animais de mesmo grupo contemporâneo seja feita por um único técnico. The repeatability of ultrasound image measurements of the longissimus dorsi muscle (AOL) and of the rumpfat (EGG) and backfat (EGL) subcutaneous thickness was evaluated. Ultrasound images taken from the back (between 12th and 13th ribs) and from the rump (between gluteus medium and biceps femoris muscles) of Nelore heifers at 14 and 22 months of age were classified as acceptable, marginal and rejected. The acceptable and marginal images were measured twice by three technicians at different levels of training. It was estimated repeatabilities among and within technicians by class of image quality in order to determine effect of image quality and of the technician at the absolute difference value between the first and second measurement of those traits. The repeatability for acceptable images was higher than for marginal images, for both among and within technicians. Regarding to the absolute difference analyses between the first and second interpretation, the effects of the technician for AOL and EGL and quality class of image for AOL were significant. In general, the repeatability was higher for the most experienced technician. It is advisable that measurements of images in the same contemporaneous group should be done by one single technician. Estação Experimental de Zootecnia de Sertãozinho APTA SAA USP Faculdade de Zootecnia e Engenharia de Alimentos Instituto de Zootecnia Universidade Federal do Rio Grande do Sul (UFRGS) Faculdade de Agronomia UNESP Faculdade de Ciências Agrárias e Veterinárias UNESP Faculdade de Ciências Agrárias e Veterinárias

A Embrapa Pecuária Sul em parceria com a Associação Brasileira de Hereford e Braford ? ABHB vem, há vários anos, desenvolvendo ferramentas tecnológicas, para que criadores de gado de corte do Sul do Brasil tomem decisões mais precisas no melhoramento genético dos seus rebanhos...

Visando estimar parâmetros genéticos em bovinos, foram utilizados registros de pesos padronizados aos 120, 210, 365, 450 e 550 dias de idade (P120, P210, P365, P450 e P550), altura do posterior mensurada próxima ao sobreano (ALT) e circunferências escrotais (CE) padronizadas aos 365, 450 e 550 dias de idade (CE365, CE450 e CE550). Os dados foram provenientes de animais machos e fêmeas, nascidos entre 1998 e 2003 em dez fazendas de seis estados brasileiros. Os componentes de (co)variância foram estimados pela metodologia REML em análises uni, bi e trivariadas, utilizando-se modelos animal. As estimativas de herdabilidade do efeito direto com os respectivos erros-padrão foram: ALT 0,63 (0,09), P120 0,25 (0,03), P210 0,34 (0,03), P365 0,45 (0,04), P450 0,48 (0,04), P550 0,49 (0,04), CE365 0,48 (0,04), CE450 0,53 (0,04) e CE550 0,42 (0,09). As correlações genéticas entre a ALT e as variáveis P120, P210, P365, P450 e P550 foram de 0,68; 0,64; 0,53; 0,58 e 0,59, respectivamente. As associações genéticas do P120 com as CE ajustadas para peso e idade foram próximas de zero, entretanto, essas correlações foram positivas e moderadas, quando as CE foram ajustadas somente pela idade. As correlações genéticas da ALT com as CE, quando ajustadas para peso e idade, foram: -0,19 (CE365), -0,24 (CE450) e 0,00 (CE550). Utilizando um modelo que não incluiu o peso do animal como covariável, as correlações genéticas das CE com a ALT foram: 0,21 (CE365), 0,12 (CE450) e 0,39 (CE550). Essas estimativas indicam que as características de crescimento e CE apresentam variabilidade genética na raça Nelore, podendo ser incluídas em programas de melhoramento genético, e a seleção para peso em qualquer idade deve acarretar aumento na estatura dos animais. Desta forma, para obtenção de animais com tamanho e peso adequados ao sistema de produção, faz-se necessária a utilização de um índice de seleção aliando estas características.