Relationships between bunk attendance, intake and performance of steers and heifers on varying feeding regimes

Abstract Six crossbred heifers (average weight 481±22kg) and six crossbred steers (average weight 471±44kg) were penned individually in pens 2m×5m in size. Feeding behaviours during ad libitum (Day 0–28) and restricted intake (95% of ad libitum; Day 29–54) were derived from bunk attendance recordings made using radio frequency technology (GrowSafe Systems Ltd.). Dry matter intake (DMI), average daily gain (ADG), feed efficiency and eating rate were recorded during the 54-day trial period. Feed was delivered at 08:30 and 13:30h daily. Eating rate was estimated by recording the amount of feed remaining 3h after each feeding (i.e. at 11:30 and 16:00h daily). Positive relationships were observed between average daily duration of bunk attendance and average DMI, and between average duration of attendance and ADG. Cattle spending more time at the bunk consumed more and gained more quickly. Feed efficiency was negatively correlated to time at the bunk ( r =−0.17; P r =0.09; P >0.10). Correlations between bunk attendance duration and average daily intake (kg per day) were ( r =0.38; P r =0.14; P P P