Autores
Lorena Ferreira Benfica, Leandro Sannomiya Sakamoto, Ana Fabrícia B. Magalhães, Matheus Henrique V. de Oliveira, Lúcia Galvão de Albuquerque, Roberto Cavalheiro, Renata H. Branco, Joslaine N. dos S. G. Cyrillo, Maria Eugênia Zerlotti Mercadante
Resumo
RESEARCH ARTICLE
Animal Genetics and Genomics
Genetic association among feeding behavior, feed eficiency, and growth traits in growing indicine cattle
Lorena Ferreira Benfica, Leandro Sannomiya Sakamoto, Ana Fabrícia Braga Magalhães, Matheus Henrique Vargas de Oliveira, Lúcia Galvão de Albuquerque, Roberto Cavalheiro, Renata Helena Branco, Joslaine Noely dos Santos Goncalves Cyrillo, Maria Eugênia Zerlotti Mercadante
This study aimed to estimate genetic parameters, including genomic data, for feeding behavior, feed ef/ciency, and growth
traits in Nellore cattle. The following feeding behavior traits were studied (861 animals with records): time spent at the feed
bunk (TF), duration of one feeding event (FD), frequency of visits to the bunk (FF), feeding rate (FR), and dry matter intake
(DMI) per visit (DMIv). The feed ef/ciency traits (1,543 animals with records) included residual feed intake (RFI), residual
weight gain (RWG), and feed conversion (FC). The growth traits studied were average daily gain (ADG, n = 1,543 animals) and
selection (postweaning) weight (WSel, n = 9,549 animals). The (co)variance components were estimated by the maximum
restricted likelihood method, /tting animal models that did (single-step genomic best linear unbiased prediction) or did
not include (best linear unbiased prediction) genomic information in two-trait analyses. The direct responses to selection
were calculated for the feed ef/ciency traits, ADG, and WSel, as well as the correlated responses in feed ef/ciency and
growth by direct selection for shorter TF. The estimated heritabilities were 0.51 ± 0.06, 0.35 ± 0.06, 0.27 ± 0.07, 0.34 ± 0.06, and
0.33 ± 0.06 for TF, FD, FF, FR, and DMIv, respectively. In general, TF and FD showed positive genetic correlations with all feed
ef/ciency traits (RFI, RWG, and FC), ADG, DMI, and WSel. Additionally, TF showed high and positive genetic and phenotypic
correlations with RFI (0.71 ± 0.10 and 0.46 ± 0.02, respectively) and DMI (0.56 ± 0.09 and 0.48 ± 0.03), and medium to weak
genetic correlations with growth (0.32 ± 0.11 with ADG and 0.14 ± 0.09 with WSel). The results suggest that TF is a strong
indicator trait of feed ef/ciency, which exhibits high heritability and a weak positive genetic correlation with growth. In
a context of a selection index, the inclusion of TF to select animals for shorter TF may accelerate the genetic gain in feed
ef/ciency by reducing RFI but with zero or slightly negative genetic gain in growth traits.
Key
words: correlation, heritability, residual feed intake, selection, time spent at the feed bunk.
Íntegra (PDF)
Veja todos os artigos
