Genetic improvement of Nellore cattle in the semi-arid region of northeastern Brazil

Acta Scientiarum: Animal Sciences

卷:37

Carlos Henrique Mendes Malhado¹  Iomar Ramos Oliveira¹  Paulo Luiz Sousa Carneiro¹  Ana Claudia Mendes Malhado²  Raimundo Martins Filho³  Ana Carla Borges Barbosa⁴ 

[1]Universidade Estadual do Sudoeste da Bahia

[2]|Universidade Federal de Alagoas

[3]|Universidade Federal do Cariri

[4]|Universidade federal da Bahia

关键词: age at first calving;    genetic progress;    genetic parameters;    heritability.;   

DOI  :  10.4025/actascianimsci.v37i4.28094

来源: DOAJ

【 摘 要 】

The semi-arid region of Brazil represents approximately 57% of the northeastern territory. The main economic activity in this region is agriculture and livestock, in most cases, using traditional technologies. However, there is little published information currently available on cattle-raising in this part of Brazil. The objective of this study was to estimate genetic parameters and trends for productive and reproductive traits of Nellore cattle raised in semi-arid region of northeastern Brazil. Data were collected on weight-adjusted at 205 (W205), 365 (W365) and 550 (W550) days of life, age at first calving (AFC), calving interval (CI) and scrotal circumference (SC) at 550 days of life of cattle born between 1965 and 2011. Estimates of covariance and variance were obtained through univariate analysis using a Gibbs sampler. The estimated coefficients of heritability (mode) were 0.27 (W205), 0.36 (W365) and 0.39 (W550), 0.37 (SC), 0.22 (AFC) and 0.03 (CI). Little or no gain from selection is apparent in the genetic trend analysis over the 45 years of the study. However, environmental improvement has allowed phenotypic progress in growth traits and age at first age calving.

【 授权许可】

Unknown