We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Genetic relationships between feed efficiency in growing males and beef cow performance.
- Authors
Crowley, J. J.; Evans, R. D.; Hugh, N. Mc; Kenny, D. A.; McGee, M.; Crews,Jr., D. H.; Berry, D. P.
- Abstract
Most studies on feed efficiency in beef cattle have focused on performance in young animals despite the contribution of the cow herd to overall profitability of beef production systems. The objective of this study was to quantify, using a large dataset, the genetic covariances between feed efficiency in growing animals measured in a performance-test station, and beef cow performance including fertility, survival, calving traits, BW, maternal weaning weight, cow price, and cull cow carcass characteristics in commercial herds. Feed efficiency data were available on 2,605 purebred bulls from 1 test station. Records on cow performance were available on up to 94,936 crossbred beef cows. Genetic covariances were estimated using animal and animal-dam linear mixed models. Results showed that selection for feed efficiency, defined as feed conversion ratio (FCR) or residual gain (RG), improved maternal weaning weight as evidenced by the respective genetic correlations of -0.61 and 0.57. Despite residual feed intake (RFI) being phenotypically independent of BW, a negative genetic correlation existed between RFI and cow BW (-0.23; although the SE of 0.31 was large). None of the feed efficiency traits were correlated with fertility, calving difficulty, or perinatal mortality. However, genetic correlations estimated between age at first calving and FCR (-0.55 ± 0.14), Kleiber ratio (KR; 0.33 ± 0.15), RFI (-0.29 ±0.14), RG (0.36 ± 0.15), and relative growth rate (RGR; 0.37 ± 0.15) all suggest that selection for improved efficiency may delay the age at first calving and we speculate, using information from other studies, that this may be due to a delay in the onset of puberty. Results from this study, based on the estimated genetic correlations, suggest that selection for improved feed efficiency will have no deleterious effect on cow performance traits with the exception of delaying the age at first calving.
- Subjects
ANIMAL feeding; BEEF cattle; ANIMAL genetic engineering; FEED biotechnology; CATTLE fertility; CATTLE parturition
- Publication
Journal of Animal Science, 2011, Vol 89, Issue 11, p3372
- ISSN
0021-8812
- Publication type
Article
- DOI
10.2527/jas.2011-3835