Weaning weight–related differences in growth performance, nutrient digestibility, blood profiles, and intestinal morphology in pigs

This study was conducted to evaluate whether weaning weight (WW) at 28 d of age could serve as an indicator of postweaning robustness by comparing growth performance, nutrient digestibility, blood profiles, and intestinal morphology of pigs differing in body weight (BW). Among a total of 124 pigs, 74 pigs corresponding to the upper and lower 30% of the WW distribution were selected and assigned to heavy BW (HBW) and light BW (LBW) groups, respectively, and monitored until d 56 of age. In this study, the HBW group showed higher (p p p < 0.05) cortisol, tumor necrosis factor-α, interleukin-6, and interleukin-10 levels in LBW group, reflecting enhanced systemic stress and inflammatory activation. Correlation analysis further demonstrated positive associations between WW and growth performance and nutrient digestibility, VH, VW and VH:CD while showing negative correlations with inflammatory and stress markers. These results indicate that WW is closely linked to postweaning physiological responses and serve as a practical predictor of robustness, digestive capacity, and growth potential during the nursery phase.