|Welsh Jr, Thomas|
|Carroll, Jeffery - Jeff Carroll|
Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 2/25/2011
Publication Date: 8/11/2011
Citation: Loyd, A.N., Vann, R.C., Banta, J.P., Welsh Jr, T.H., Carroll, J.A., Randel, R.D. 2011. Characterization of feeding behavior of abrupt-weaned crossbred heifer calves [abstract]. Journal of Animal Science. 89:419(E-Suppl. 1). Interpretive Summary:
Technical Abstract: Stress experienced by calves at weaning often culminates in poor post-weaning feed intake (FI) and growth performance. Understanding feeding behavior during this time is crucial to successful management of these calves. The objective of this study was to characterize the feeding behavior of calves post-weaning. Brahman x British heifers (n = 48) born in spring 2010 at the Brown Loam Branch Experiment Station in Raymond, MS, were abruptly weaned from their dams at 199 ± 18 d of age. Heifers were penned in one of two dry-lots and received ad libitum access to a high roughage diet offered in GrowSafe® bunks. Feeding behavior was monitored for 24-26 d post-weaning and BW was evaluated weekly beginning at weaning. Data were analyzed using the MIXED procedure of SAS with day as a repeated measure when applicable. The number and duration of daily meal events, the duration of daily head down time, and daily FI increased with time post-weaning (P < 0.0001). Body weight was similar for all time-points (P = 0.32). However, there was great variation in the number of days it took heifers to first approach the feed bunks, eat feed for the first time, eat feed consistently for at least 5 d, and consume enough feed to meet estimated NEm requirements. To account for this variation, the proportion of Brahman influence was included in the statistical model as a covariate. Brahman-influenced heifers were slower to attend the bunks (P < 0.0001), begin consuming feed (P < 0.0001), consistently consume feed (P < 0.0001), and consume enough feed to meet NEm requirements (P < 0.03). However, there was no effect (P > 0.10) of breedtype on feeding behavior or FI over the course of the entire feeding period. These data suggest there is considerable variation in post-weaning feeding behavior, of which some is attributable to breedtype. These data also highlight an important consideration when utilizing newly weaned calves in feeding trials, especially those using GrowSafe® bunks.