Fatores de correção do perímetro escrotal para efeitos de idade e peso ao sobreano de tourinhos nelore
Carregando...
Arquivos
Data
1998-11-01
Autores
Dal-Farra, Rossano André
Fries, Luiz Alberto [UNESP]
Lobato, José Fernando Piva
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
The aim of the study was to estimate adjustment factors to be used in genetic selection programs. Measurement data of scrotal circumference Nellore breed bulls from different herds raised on Brazilian tropical pasture conditions, totalizing 8934 animals of the 346 contemporary groups (CG) were analyzed. The means and standard deviations of real scrotal circumference (PEREAL), age at yearling weight (ISOB) and yearling weight adjusted to 550 days (PPD550), and age-of-dam were, respectively: 28.44 ± 3.35 cm; 589.04 ± 42.66 days; 333.03 ± 36.25 kg and 5.84 ± 3.01 years. The segmented polynomials (Spline functions) were used to estimate the adjustment factors for age and yearling weight, being used 550 days and 330 kg for age and weight, respectively, as standard values. Anticipation scrotal circumference measurements for 520-550 days could increase the selection efficiency for sexual precocity.
Descrição
Palavras-chave
Scrotal circumference to weight ratio, Segmented polynomials, Sexual precocity, Spline functions, Animalia
Como citar
Revista Brasileira de Zootecnia, v. 27, n. 6, p. 1092-1096, 1998.