Abstract

Heart rate (HR; beats/min) rumen temperature (RTMP; ºC), activity level (ACT; %) and feeding patterns (feeding event duration; sec/30 min, feed intake; kg/30 min, visits to the feeder; visits/30 min) have been suggested as feed efficiency (residual feed intake; RFI; kg/d), distress and health status indicators in cattle holding potential for development into practical on-farm decision making tools. Our study assessed the associations between these parameters when feedlot cattle (n=22) were eating or not eating (FI dataset), at differing activity levels (ACT dataset) and between feed efficient and feed inefficient cattle (RFI dataset). Heart rate was not different between FI, ACT and RFI groups. RTMP was lower in high ACT then low ACT observations (39.64±0.15 vs 40.08±0.15; P=0.001) and was associated with ACT in positive RFI cattle (r=-0.55; P <0.001). Activity levels in the ACT dataset were lower when cattle were located in the yard then when located in the pen or abattoir. Associations between RTMP and ACT across ACT and RFI datasets promote these as potential indicators of feed efficiency and health status in cattle. Changes in ACT across locations suggest it to be a potential indicator of distress. Future studies assessing RTMP and ACT abilities to determine performance are warranted.

JC, Munro, FS Schenkel, SP Miller, T Tennessen, and YR Montanholi

Proceedings of the New Zealand Society of Animal Production, Volume 75, Dunedin, 29-33, 2015