Effects of early weaning on weight gain, serum immune, biochemical and trace element indices of Albas cashmere goats

In order to study the effects of different weaning ages on weight gain and, serum immune, biochemical and trace element indexes of Albas cashmere goats, and to determine the suitable early weaning time of Albas cashmere goats, 24 healthy male Albas cashmere goat lambs with the same birth age and similar weight were selected for the experiment. They were randomly divided into 4 groups（30 d weaning group, 40 d weaning group, 50 d weaning group and 60 d weaning control group）, with 6 lambs in each group. The lambs in the 30 d weaning group, the 40 d weaning group and the 50 d weaning group were weaned gradually（a 10-day transition period was set） at 30,40 and 50 days, respectively. The lambs in the 60 d weaning control group was weaned directly at 60 days. Lambs in each group were weighed every 10 days starting from day 30, and the average daily gain in 10 days was calculated.The levels of（immunoglobulin, Ig） A, IgG and IgM in serum were detected by blood sampling before morning feeding on the 90th day. Serum biochemical indexes（total protein TP, total cholesterol TC, creatinine CREA, urea UREA, blood glucose GLU, total bilirubin TBIL, creatine kinase CK, alkaline phosphatase ALP） and trace element indexes（iron, magnesium, zinc, cadmium, lead, copper, manganese） were measured before morning feeding on day 60 and 90. The effects of early weaning on weight gain and serum immune, biochemical and trace element indexes of Albas cashmere goats were analyzed.The results showed as follows: on days 31 to 40 of the experiment, the average daily gain of lambs at 10 days of age in the 40 d weaning group was higher than that in the 30 d weaning group（P＜0.05）, 50 d weaning group（P＜0.05）, and 60 d weaning control group（P＞0.05）; at days 41 to 50, 51 to 60, 61 to 70, 71 to 80 and 81 to 90, there was no significant difference in the 10-day average daily gain of lambs among all groups（P＞0.05）. On the 60th day of the experiment, there were no significant differences in the serum levels of TP, TC, UREA, GLU, CK and ALP among all groups（P＞0.05）, and the CREA and TBIL levels of lambs in the 30 d weaning group were significantly lower than those in the 60 d weaning control group（P＜0.05）; there were no significant differences in the serum levels of iron, magnesium, zinc, cadmium, lead, copper and manganese among all groups（P＞0.05）; the serum levels of iron, magnesium, zinc, cadmium, lead, copper and manganese of lambs in all groups were within the normal reference value, except that the serum levels of iron in the 30 d weaning group and the 40 d weaning group were lower than the normal reference value. On the 90th day of the experiment, the serum IgA level in the 30 d weaning group was higher than that in the 40 d weaning group（P＞0.05）, 50 d weaning group（P＜0.05）, and 60 d weaning control group（P＞0.05）; there were no significant differences in serum levels of IgG, IgM,TP, TC, CREA, UREA, GLU, TBIL, CK and ALP among all groups（P＞0.05）; there were no significant differences in the serum levels of iron, magnesium, zinc, cadmium, lead, copper and manganese among all groups（P＞0.05）, and the serum levels of iron, magnesium, zinc, cadmium, lead, copper and manganese of lambs in all groups were within the normal reference value, except that the serum iron level of lambs in the 30 d weaning group was lower than the normal reference value.The results indicated that early weaning of Albas-velvet goats was feasible, and the effect of weaning at 40 days was better.