热应激环境蛋鸡免疫力变化机理研究 Ⅰ免疫力、血浆皮质酮、耐热力之间的关系

The study of layers on the immune feature and relation with HSST Ⅰ Change of immune index and relation of that with plasma corti costerone,HSST

选经常规免疫 ND、IBD的 30周龄健康罗曼蛋鸡 96只 ,按随机法等分为两组 ,分别置于 2个人工气候室内 ,对照组环境温度保持 2 2℃不变 ,试验组环境温度为 2 2℃ 7d,30℃ 7d,35℃ 7d,40℃ 4h(部分 1～ 43h) ,2 1.3℃ 2 2 h。在不同温度段定期采血并作 40℃ 15只鸡致死时间 (heatstress survival time,HSST)测定。结果表明 ,135℃ 16 6 h,40℃ 4h能显著降低蛋鸡血液 T淋巴细胞百分率 ,T、B细胞转化率和 ND、IBD抗体水平。解除热应激 2 1.3℃ 2 2 h免疫指标均未恢复正常 ,ND、IBD抗体水平消减速度趋缓。2 30℃ 16 6 h,35℃ 16 6 h,40℃4h均使蛋鸡血浆皮质酮显著上升 ,2 1.3℃ 2 2 h尚未恢复正常。 3高温期蛋鸡免疫力指标下降率与其血浆皮质酮的升高百分率呈显著或极显著正相关 ,与其耐热力 (HSST)呈显著负相关。

day healthy Roman layers which are routinely immuned to ND and IBD are selected and divided into 2 groups,and respectively put into 2 artificial climate rooms.The temperature of contrast group keeps at 22 ℃,and the that of test group is at 22 ℃ 7 d,30 ℃ 7 d,35 ℃ 7 d,40 ℃ 4 h(part of them are 1-43 h),21.3 ℃ 22 h.15 layers HSST (heat stress survival time) is measured at 40 ℃ in different period by taking a blood sample periodically.The result showed that:① the percent of T lymphocyte,the rate of transforming between T lymphocyte and B lymphocyte and antibody levels of ND and IBD are decreased obviously at 35 ℃ 166 h and 40 ℃ 4 h.Immune index is not recovered to the normal after removing heat stress 21.3 ℃ 22 h,and the speed of antibody rate of ND and IBD is decreased moderately.② Plasma corticosterone of layers is raised obviously at 30 ℃ 166 h,35 ℃ 166 h,40 ℃ 4 h,and is not recovered to the normal at 21.3 ℃ 22 h.③ There is significantly positive relationship between the decreasing rate of the immune indexes and the increasing rate of the plasma corticosterone at high temperature,but it is significantly negative relationship between the immune indexes and HSST.