Phenotypic and genetic correlations of beef replacement heifer feeding behaviour, feed intake and feed efficiency with cow performance and lifetime productivity

Citation

Olson, C.A., Li, C., Block, H., McKeown, L., Basarab, J.A. (2021). Phenotypic and genetic correlations of beef replacement heifer feeding behaviour, feed intake and feed efficiency with cow performance and lifetime productivity. Journal of Animal Breeding and Genetics, [online] 138(3), 300-313. http://dx.doi.org/10.1111/jbg.12522

Plain language summary

Early-life traits as a heifer may be used in genetic selection to improve cow reproductive performance. In this study, feeding behaviors and feed intake of 1145 crossbred replacement beef heifers from feedlot tests were evaluated for genetic correlations with their performance as cows over parities one to four. The results showed that heifers that spent more time in the feedlot eating had greater pre-breeding body weights as cows whereas heifers that visited feed bunks more frequently tended to have smaller cow pre-breeding body weights. Heifers that ate more, i.e. had a higher dry matter intake, showed greater cow pre-breeding body weights. The moderate genetic correlations of the feeding behavior traits and dry matter intake with cow body weight suggest that caution would be required in genetic selection to prevent an increase in mature cow size. Therefore, the genetic parameters from this study will help design a better selection program that optimizes performance of feeding behavior, dry matter intake, feed efficiency, body weight, and cow productivity in beef cattle.

Abstract

Objectives were to quantify the phenotypic (rp) and genetic (rg) correlations between early-life feeding behaviours, dry matter intake, and feed efficiency and measures of cow performance and lifetime productivity traits. Traits were measured on 1,145 crossbred replacement beef heifers and then on cows over parities one to four. Feeding event duration (FD) was phenotypically correlated with cow prebreeding body weight (PBWT; rp 0.29–0.45), cow prebreeding back fat thickness (PBBF; rp 0.35–0.49), progeny weaning weight (WW; rp 0.09–0.31) and progeny birthweight (BW; rp −0.06 to 0.17). Feeding event frequency (FF) was phenotypically correlated with PBBF (rp 0.16–0.30). Dry matter intake (DMI) was phenotypically correlated with PBWT (rp 0.16–0.20) and PBBF (rp −0.22 to −0.05). Feeding event duration was genetically correlated with PBWT (rg 0.38–0.41). Feeding event frequency was genetically correlated with PBWT (rg −0.43 to −0.39). Dry matter intake was genetically correlated with PBWT (rg −0.27 to 0.14). Days in herd (DIH) was phenotypically correlated with FD and DMI (rp = 0.12, 0.20, respectively). Lifetime productivity was phenotypically correlated with FD and FF (rg = 0.25, 0.22, respectively). Calving interval was phenotypically correlated with FD and FF (rp = −0.12, −0.14, respectively) and genetically correlated with FF (rg = −0.41). Due to moderate positive correlations with cow weight, caution would be required in selection to prevent an increase in mature cow size. Use of FF, FD, DMI and a measure of feed efficiency such as residual feed intake adjusted for back fat (RFIFAT) in a balanced selection index is recommended.

Publication date

2021-05-01