Effect of amount of milk fed, weaning age and starter protein level on growth performance in Holstein calves
The objectives of this study were to investigate the effects of amount of milk fed, weaning age and difference of starter protein levels on growth performance of female Holstein Friesian calves. Forty Holstein calves were housed in individual boxes. Calves were divided into 2 groups (n=20); first group was fed with whole milk with the amount of 10 % of their body weight (BW), while the second group was fed with whole milk with the amount of 8 % of their BW. These 2 groups were divided into sub-groups of calves (n=10 for each) again. One of the sub-groups was fed with whole milk for a period of 8 weeks, while the other group was fed with whole milk for a period of 5 weeks. Once again the sub-groups were divided into 2 groups (n=5 for each). One of these groups was fed with starter diet containing 22 % crude protein (CP), while the other group was fed with starter diet containing 18 % CP ad libitum as the starting feed. After an 8-week period, Calves which were fed by the whole milk of %10 of their BW were defined to be heavier than those which were fed by %8 whole milk of their BW. The effect of weaning age and protein level of starter on BW was not statistically significant. The results showed that the body weight gains of the calves receiving milk at 10 % of BW were better, early weaning tended to increase feed consumption and the protein levels did not affect the performance of calves.