Seleção para características reprodutivas em bovinos de corte da raça Nelore
Data
2015-07-31
Autores
Moreira, Heverton Luis
Buzanskas, Marcos Eli [UNESP]
Munari, Danisio Prado [UNESP]
Canova, Érika Breda
Lôbo, Raysildo Barbosa
de Paz, Claudia Cristina Paro
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Genetic breeding programs of beef cattle in Brazil are including new features, mainly related to reproductive efficiency. Thus, it is necessary to study the effectiveness of selection and quantify genetic gain for these traits in herds. This study estimated genetic and phenotypic parameters and genetic trends for reproductive traits used in breeding programs for Nelore beef cattle. The traits studied were the scrotal circumference (SC) at 365 and 450 days of age (SC365 and SC450), age at first calving (AFC) and gestation length, as a cow trait (GLcow) and a calf trait (GLcalf). The (co)variance components were obtained with the Restricted Maximum Likelihood Methodology in a single and double-trait analysis of the animal model. For scrotal circumference (SC365 and SC450), positive and favorable genetic gains were observed. For AFC, GLcow and GLcalf, the trends were favorable for selection, but without significant genetic gain. Selection for large SC may reduce AFC and improve female reproductive efficiency. The selection for reproductive traits (SC365, SC450, AFC and GL) may improve reproductive and productive efficiency of Nelore cattle, if used as a selection criterion.
Descrição
Palavras-chave
Genetic evaluation, Precocity, Reproductive efficiency
Como citar
Ciencia e Agrotecnologia, v. 39, n. 4, p. 355-362, 2015.