限位栏对孕猪应激水平及神经内分泌HPA轴的影响

Effect of Restraint Stress on Stress Level of Pregnant Sows and Neuroendocrine HPA Axis

为了研究限位栏饲养对妊娠母猪应激水平的影响,本试验选取6头8~9月龄的巴马小型母猪,配种成功后随机分成2个组,试验组(n=3)采用限位栏饲养,对照组(n=3)自由环境饲养,其余饲养管理一致。于妊娠第18天终止妊娠,取母猪下丘脑、肾上腺、海马和血液,采用酶联免疫吸附试验(ELISA)、放射免疫测定法(RIA)、实时荧光定量PCR技术、蛋白免疫印迹(WB)和H.E.染色对应激相关激素及受体表达水平进行检测。结果显示,与对照组相比,试验组血浆中皮质醇(COR)、促肾上腺皮质激素(ACTH)和促肾上腺皮质释放激素(CRH)水平均显著上升(P≤0.05);肾上腺皮质部束状带充血且细胞水肿,海马中应激蛋白受体表达下降(P≤0.05),同时下丘脑中糖皮质激素受体表达上升(P≤0.05);下丘脑和海马中5-羟色胺能信号传入减少(P≤0.05)。结果表明,制动应激可能导致下丘脑-垂体-肾上腺(HPA)轴反应性降低且海马的副调控功能减退。

In order to study the stress level of pregnant sows fed in limit pens,this study selected 6 Bama miniature sows aged 8-9 months.After successful breeding,they were randomly divided into two groups.Except that the experimental group(n=3)was reared in limit column and the control group(n=3)was reared in a free environment,the other rearing management was identical.The pregnant sows were sacrificed on the 18th day of pregnancy,and the hypothalamus,adrenal glands,hippocampus and blood were taken,and the levels of stress-related hormones,adrenal glands and stress-related receptors were determined by ELISA,radioimmunoassay,fluorescent PCR,Western Blot and H.E.staining.The results showed that compared with the control group,the levels of cortisol(COR),adrenocorticotrophic hormone(ACTH),and corticotropin releasing hormone(CRH)in the plasma of the experimental group increased significantly(P≤0.05);the adrenal cortex tract congestion and cell swelled;the expression of stress protein receptors in the hippocampus decreased,and the expression of corticosteroid receptors in the hypothalamus increased;the 5-HT signal in the hypothalamus and hippocampus decreased.The results indicating that HPA axis responsiveness decreased and the hippocampus side-regulatory function decreased.