Data/hora: 04/06/2024 04:02:53

Provedor de dados: | 96
País: | Brazil
Título: | Genetic analysis of visual scores and their relationships to mature female weight in Nellore breed
Autores: | Regatieri,Inaê Cristina; Boligon,Arione Augusti; Albuquerque,Lucia Galvão de.
Data: | 2011-01-01
Ano: | 2011
Palavras-chave: | Beef cattle; Conformation; Genetic correlation; Musculature; Precocity.
Resumo: | Data from 79,884 Nellore breed animals were used to estimate genetic parameters and to evaluate the relationships among scores of conformation, precocity and musculature obtained at weaning and after yearling ages and weight of mature females. It was used the restricted maximum likelihood method in a multi-trait analysis with the model that included direct additive genetic and residual effects, as random effects, and the fixed effects of contemporary group and, as covariables, animal age at weighing and age of dam at calving (except for weight of females at adult age). Contemporary groups at weaning were defined by the variables: sex, herd, year and month of birth, and management group at birth and weaning. For definition of contemporary group at yearling, it was also included the variable management group at yearling. For female weight at mature age, contemporary group was composed of herd, year of birth, management group at yearling, weighing year and season. Maternal genetic and maternal permanent environment effects were also included in the model for analyses of scores of conformation, precocity and muscularity at weaning. The direct herdability estimates obtained were the following: 0.18 ± 0.02 for conformation at weaning score, 0.21 ± 0.01 for precocity at weaning score, 0.22 ± 0.01 for muscularity at weaning score, 0.24 ± 0.01 for conformation at yearling score, 0.27 ± 0.01 for precocity at yearling score, and 0.26 ± 0.01 for muscularity score at yearling and 0.42 ± 0.02 for mature female weight. Genetic correlations estimated among visual scores measured at weaning and after yearling were positive, ranging from intermediate to high magnitude (0.56 ± 0.03 to 0.85 ± 0.01). On the other hand, genetic correlations estimated between visual scores and mature female weight were positive and intermediate, ranging from 0.21 ± 0.03 to 0.35 ± 0.03. The results obtained indicate that selection of animals with higher visual scores, mainly at yearling age, may promote an increase on mature female weight.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000100014
Editor: | Sociedade Brasileira de Zootecnia
Relação: | 10.1590/S1516-35982011000100014
Formato: | text/html
Fonte: | Revista Brasileira de Zootecnia  v.40 n.1 2011
Fonte: | info:eu-repo/semantics/openAccess