Antioxidant Effect of Taurine on Chronic Heat-Stressed Broilers.

The purpose of this study was to investigate the effects of taurine on blood indices of broilers with chronic heat stress and to provide theoretical basis for the application of taurine in the anti-chronic heat stress of broilers. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5 g/L, 2 g/L, and 8 g/L taurine, were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, MTau significantly increased the total serum protein content (P < 0.05), but the other groups were not significantly different (P > 0.05). The MTau and HTau groups contained significantly lowered serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all exhibited significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups at other times (P > 0.05). Compared with the HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). Compared with the LTau, MTau, and HTau groups, serum MDA content was significantly increased in the heat-stressed broilers (P < 0.05). MTau group contained significantly increased T-AOC, SOD, CAT, and GSH-PX levels (P < 0.05). The other groups were not significantly different (P > 0.05). Compared with group C, serum HSP60 and HSP70 levels were significantly elevated in the HS group (P < 0.05). Compared with the HS group, the LTau and MTau groups contained significantly increased serum HSP60 and HSP70 concentrations (P < 0.05), but the other groups were not significantly different (P > 0.05). In conclusion, taurine can alleviate the symptoms of chronic heat stress of broilers, regulate the metabolism of the body, and improve the antioxidant activity of the body.