慢性热应激对舍饲西门塔尔母牛免疫功能、抗氧化能力和生产性能的影响

Effect of chronic heat stress on immune function,antioxidant capacity and production performance of Simmental cattle

试验旨在探究慢性热应激对舍饲西门塔尔母牛免疫功能和抗氧化能力的影响。选取10头体况相近健康的舍饲西门塔尔母牛,试验期根据牛舍环境温度和湿度变化分为热应激期和非应激期,每个试验期为10 d。结果显示,与非应激期相比,舍饲西门塔尔母牛在热应激状态下血清免疫球蛋白A(IgA)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、白细胞介素-2(IL-2)含量显著降低(P<0.05),白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)含量显著升高(P<0.05);舍饲西门塔尔母牛在热应激状态下血清过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC)显著降低(P<0.05),血清丙二醛(MDA)含量显著升高(P<0.05);血清胰岛素(INS)含量显著升高(P<0.05),葡萄糖(GLU)、非酯化脂肪酸(NEFA)、生长激素(GH)、胰岛素样生长因子1(IGF-1)的含量显著降低(P<0.05)。研究表明,慢性热应激会抑制舍饲西门塔尔母牛免疫功能和抗氧化能力,可能使肉牛机体内产生炎症反应,对西门塔尔母牛器官组织细胞造成损伤。

The experiment was to explore the effect of chronic heat stress on immune function and antioxidant capacity of Simmental cattle fed in captivity.Ten Simmental cattle fed in captivity with similar health body condition were selected,and the test period was divided into cold stress period and non-stress period according to changes in the ambient temperature and humidity of cattle shed.The results showed that compared with the non-stress period,IgA,IgG,IgM and IL-2 in serum of Simmental cows fed in captivity under heat stress were significantly decreased(P<0.05),IL-1β,IL-6,and TNF-αcontent was significantly increased(P<0.05).CAT,GSH-Px,SOD activity and T-AOC in serum of Simmental cows under heat stress were significantly decreased under heat stress(P<0.05),and the content of MDA in serum was significantly increased(P<0.05).The content of INS in serum of simmental cows fed in captivity was significantly increased under heat stress(P<0.05),and the content of GLU,NEFA,GH and IGF-1 was significantly decreased(P<0.05).The study indicates that chronic heat stress inhibits the immune function and antioxidant capacity of cows fed in captivity,and may cause inflammatory reaction in the body of beef cattle,damage to the tissue cells of the organs of the Simmental cattle.