Impact of early weaning and nutritional interventions on growth performance, digestive metabolism, and serum biomarkers in lambs: A biomechanical perspective

The aim of this study was to investigate the effects of early weaning and nutritional interventions on growth performance, nutrient digestion and metabolism, and serological indices of hu sheep lambs, with a view to providing a basis for the feasibility of early weaning of hu sheep lambs under conditions of supplemental milk replacer. Ninety neonatal hu sheep lambs were weaned at 21 days (n = 60) (divided into two groups: early weaned, EW; and resveratrol-fed, RSV) as well as 49 days (n = 30) (control group, CON) weaning, and the trial period was 90 days. The results showed that: 1) there was no significant difference (P > 0.05) in the initial and final weights of the lambs, and the average daily gain (ADG) of the EW and RSV groups was significantly lower than that of the CON group (P < 0.05) from 31 to 45 days of age. Early weaned lambs were more susceptible to weaning stress compared to late weaned lambs and the effect of nutritional intervention (feeding resveratrol) on lamb growth performance was not significant. 2) The apparent digestibility of crude protein (CP) in the experimental group was significantly lower than that of the control group (P < 0.05), and the nitrogen intake, net protein utilization and protein biological value indexes of lake lambs in the experimental group were significantly different from those of the control group (P < 0.05). 3) Early feeding of resveratrol was not significant in improving the digestive metabolism of nutrients. 4) Early weaning as well as the addition of resveratrol had a significant effect on the serum GLU and TC indexes of the lambs (P < 0.05), but did not show a significant effect on any of the other indexes.