PSXIII-B-15 Late Weaning Improves Growth and Reduces the Breeding age in Alpine Dairy Goats

Abstract

Abstract The aim was to evaluate the effect of weaning age on growth in Alpine dairy goats. Thirty-six female kids were randomly assigned to one of 3 treatments: 1) early weaning at 6 wk of age (6-wk), 2) weaning at 8 wk of age (8-wk), and 3) late weaning at 10 wk of age (10-wk). Treatments were blocked by BW and birth date, and each female kid was housed with a male companion of similar age and BW. Kids had ad libitum access to acidified milk replacer (ME=4.7 Mcal/kg DM), kid starter (ME=2.35 Mcal/kg DM), hay (ME=1.26 Mcal/kg DM) and water. Weaning was performed progressively over 7 d. For the 12 wk period, feed intakes for 6-wk, 8-wk and 10-wk were respectively: 135, 201 and 287 g/d for milk replacer; 90, 68, 54 g/d for hay; 25, 19 and 13 g/d for starter feed. Total ME intake was higher when increasing weaning age (6-wk, 281 kcal/d; 8-wk, 303 kcal/d; 10-wk, 371 kcal/d, P< 0.05). Interestingly, at weaning, total ME intake dropped more markedly when weaning was early (6-wk, 95 kcal/d; 8-wk, 297 kcal/d; 10-wk, 451 kcal/d, P< 0.05). 10-wk had higher BW at 12 wk of age (23.9 kg), compared with 6-wk (21.2 kg, P=0.004), and a trend was observed with 8-wk (22.2 kg, P=0.059). This effect of weaning age on BW was prolonged over time with heavier BW in 10-wk at 8 months (36.1 kg), compared to 6-wk (33.6 kg, P=0.04), and a trend was observed with 8-wk (34.0 kg). Using growth curves, extending the weaning age of dairy goats allowed to reach the breeding BW target of 32 kg sooner (6-wk, 191 d; 8-wk, 188 d; 10-wk, 161 d, P< 0.05). Overall, weaning kids at 10 wk limited the negative impact of earlier weaning on growth in the Alpine breed.