Impact of insulin-like growth factor 1, immunoglobulin G and vitamin A in colostrum on growth of newborn Black Bengal goats and its crossbred.

The study aims to investigate the relationships between colostral concentrations of insulin-like growth factor 1 (IGF-1), immunoglobulin G (IgG) and vitamin A (Vit A) and growth (body weight and average daily gain) in Black Bengal (BB) and its crossbred. The colostrum from dams (n = 16) was collected at parturition to measure the concentrations of IGF-1, IgG and Vit A. The kid weight at birth (W-0), day 14 (W-14) and day 28 (W-28) were measured and the average daily gain during day 1-14 (ADG1-14) and day 14-28 (ADG14-28) were calculated. The average concentrations of IGF-1, IgG and Vit A in colostrum were 504.6 ± 74.9 ng/ml, 9.7 ± 0.6 mg/ml and 549.1 ± 72.5 µg/100 g, respectively. The average body weight of kids at birth, day 14 and 28 were 1.72 ± 0.08, 2.95 ± 0.11 and 3.94 ± 0.13 kg respectively. Kid's breed, IGF-1, IgG and Vit A had significant positive effects on ADG14-28 while parity, litter size and sex had no effect. The growth factors that were classified into 2 classes based upon the mean values of colostral contents in all kids showed that the kids receiving the higher concentrations of IGF-1, IgG and Vit A in colostrum had higher body weight gain than those receiving the lower concentrations (92.1 ± 7.8 vs. 59.8 ± 5.7 g/day; p = 0.002, 88.3 ± 7.8 vs. 60.3 ± 6.1 g/day; p = 0.009 and 91.1 ± 6.8 vs. 56.7 ± 5.8 g/day; p < 0.001 respectively). It is concluded that IGF-1, IgG and Vit A concentrations in colostrum of dams were associated with increased kid's body weight gain at the end of first month in BB and BB crossbred goats.