Excessive dietary taurine supplementation reduces growth performance, liver and intestinal health of weaned pigs

Abstract

This study was conducted to investigate the effects of dietary taurine (Tau) supplementation on growth performance, liver and intestinal health of weaned pigs. A total of 96 cross 28-d old barrows weaned at 21±2d (initial average BW=7.39±0.40kg) were allotted randomly on the basis of the initial body weights (BW) to dietary Tau supplementation of 0%, 0.3%, 1.5%, and 3% for 28d. Each treatment had six replicate pens, and each pen had four pigs. Our results showed that gain/feed ratio (G/F) increased with the lower supplementation of Tau but decreased with the higher supplementation (quadratic, P<0.05). The liver antioxidant enzyme activities (SOD, GSH-PX and T-AOC) were lower (P<0.05) in pigs fed 0% and 3% Tau than those fed 0.3% Tau, and the lipid peroxidation (MDA) contents were lower (P<0.05) in pigs fed 0% and 0.3% Tau than those fed 1.5% and 3% Tau, which combined with the hepatic pathological analysis indicated that dietary supplementation with appropriate Tau could help maintain liver health but dietary supplementation with excessive Tau would lead to liver damage. In addition, dietary supplementation with 0.3% Tau increased (P<0.05) villus heights related to the control group. Meanwhile, the higher diarrhea index (P<0.05), lower (P<0.05) villus heights and deeper (P<0.05) crypt depths in pigs fed 3% Tau than those fed 0% or 0.3% Tau may be partially due to increased inflammatory cytokines (IL-6 and TNF-α) and Caspase-3 levels, and decreases in GLP-2 secretions. In conclusion, our results suggested that appropriate (0.3%) Tau supplementation in diets had different degrees of beneficial effects on piglet health but excessive (1.5% or 3%) Tau had adverse effects on growth performance, liver and intestinal health of piglets.