Effect of social housing on pre- and post-weaning intake and performance of dairy calves
This study investigated how pre-weaning housing environment affects intake and performance of dairy calves during the milk-feeding stage and once group-housed after weaning. Twenty Holstein bull calves were housed either individually (IH; n = 10) or paired and housed in pens (PH; n = 5) from birth until 49 d of age. Calves were offered grain concentrate (23 % CP) and milk replacer (26 % CP, 16 % fat, 150 g DM/L) ad libitum and weaned by incrementally diluting the milk replacer from 39-49 d of age. Post-weaning, IH calves were paired within treatment and all calves were offered a complete pelleted diet (21 % CP) ad libitum and followed until 84 d of age. Feed intake was recorded daily and calves were weighed 2x/wk. Data were summarized by week and analyzed in a repeated measures general liner mixed model. Intake of milk replacer was similar between treatments (9.84 L/calf/d, SE = 0.82, P = 0.9). Pre-weaning concentrate intake was subject to a treatment × wk interaction (P = 0.014), with PH calves increasing solid feed intake to a greater extent over time (in wk 5-6, 0.17 vs. 0.051 kg/d, SE = 0.031). During the 10 d of weaning, PH calves had greater concentrate intake than IH calves (0.69 vs. 0.30 kg, SE = 0.11, P = 0.039). Growth was similar between treatments prior to weaning (1.05 kg/d, SE = 0.10, P = 0.5), but PH calves had greater ADG during the 10 d of weaning (0.67 vs. 0.41 kg/d, SE = 0.07, P = 0.02). Once all calves were pair-housed after weaning, there was no effect of pre-weaning housing environment on intake (3.3 kg/d, SE = 0.15, P = 0.9) or ADG (1.21 kg/d, SE = 0.07, P = 0.2). These results indicate that social housing for dairy calves encourages solid feed intake during the milk-feeding stage, resulting in improved intake and weight gain during the weaning period.
Keywords: dairy calf, social housing, feed intake