C.A. Almeida, B.C.A. Silva, F. de Oliveira Bussiman, R.S.B. Carvalho, E.C. Mattos, J.P. Eler, M.H.A. Santana, J.B.S. Ferraz
Published: January 22, 2024
Genet. Mol. Res. 23(1): GMR19177
DOI: https://doi.org/10.4238/gmr19177
Cite this Article:
C.A. Almeida, B.C.A. Silva, F. de Oliveira Bussiman, R.S.B. Carvalho, E.C. Mattos, J.P. Eler, M.H.A. Santana, J.B.S. Ferraz (2024). Feed efficiency negatively associated with reproductive traits in Nellore cattle. Genet. Mol. Res. 23(1): GMR19177. https://doi.org/10.4238/gmr19177
About the Authors
C.A. Almeida, B.C.A. Silva, F. de Oliveira Bussiman, R.S.B. Carvalho, E.C. Mattos, J.P. Eler, M.H.A. Santana, J.B.S. Ferraz
Corresponding Author
C.A. Almeida
Email: carolineassisalmeida@gmail.com
ABSTRACT
Various studies have been conducted to improve feed efficiency in Nellore beef cattle, as well as to select for more sexually precocious animals. In order to understand how reproduction is affected by selection for feed efficiency, we analyzed a database containing phenotypic information from 194,063 Nellore animals, a pedigree file containing 331,752 animals, and a genotyping file of 7,631 animals. The evaluated traits were probability of pregnancy at 14 months (PP14), stayability (STAY), cumulative annual productivity (COWPROD), residual feed intake (RFI), residual body weight gain (RG), and residual intake and gain (RIG). The (co)variance components were estimated through a multi-trait Bayesian linear-threshold model combination. The heritability estimates were: 0.38 ± 0.03 for PP14, 0.23 ± 0.02 for STAY, 0.14 ± 0.00 for COWPROD, 0.18 ± 0.05 for RFI, 0.21 ± 0.05 for RG and 0.18 ± 0.05 for RIG. Estimates of genetic correlation coefficients between feed efficiency and reproduction traits were unfavorable for selection, 0.10 (RFI and PP14), -0.16 (RG and PP14), -0.11 (RIG and PP14), 0.12 (RFI and STAY), -0.21 (RG and STAY), -0.13 (RIG and STAY), and -0.16 (RG and COWPROD), indicating that selection for these feed efficiency traits could reduce the probability of early pregnancy of heifers and decrease the number of cows that remain in the herd for at least six years. Considering the importance of reproduction for beef cattle production and the costs of feeding the cattle, examining their genetic association with better modeling strategies could help breeders and researchers to overcome such unfavorable relationships between feed efficiency and reproduction.
Key words: Beef cattle, Genetic association, Linear-threshold model, Sexual precocity, Stayability.