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We aimed to evaluate the impact of using embryo transfer (ET) information on weaning weight estimated breeding values (EBV) and its accuracy. Data from Hereford and Braford cattle, raised under extensive conditions in Southern Brazil, were used. A model that included ET information in addition to maternal (genetic and permanent environmental) effects as a function of foster dams was compared to a model without ET information. Accuracy of both bulls and calves increased due to inclusion of ET records in 0.04 and 0.12 points, respectively. In general, the inclusion of ET records provided a greater amount of phenotypic variance and most accurate EBV for sires and progeny. The results obtained in this study encourage the use of ET phenotypic records in large-scale genetic evaluation programs, especially for bulls that have most of their progeny coming from ET. Most of the Brazilian genetic evaluation programs do not use phenotypic records of ET animals. Therefore, breeding values are predicted based only on parentage average, which implies in underestimated accuracies. Considering that ET has been widely used in Brazil and that such information improves genetic predictions, we suggest modifying the traditional adopted models by considering ET information in the Brazilian genetic evaluations.

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

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