复方中药缓解产蛋鸡热应激研究

Research of Chinese herbal compound in relieving heat stress of laying hens

热应激是夏季畜禽养殖生产性能下降主要因素。为探讨复方中药对热应激禽类相关生产性能作用,试验选取85周龄海兰褐壳蛋鸡60只,随机分为正常对照组、热应激对照组、复方中药组,试验为期21 d。正常对照组全天温度控制在25~28℃,湿度40%;热应激对照组、复方中药组每天光照10 h,温度控制在30~37℃,湿度55%,其余时间温湿度控制同正常对照组。复方中药组日粮添加1%复方中药。试验通过检测蛋鸡日采食量、粪料比、肠道排空时间、脾指数、产蛋率、谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-Px)、超氧化物歧化酶(Superoxide dismutase, SOD)、丙二醛(Malondialdehyde, MDA)、热休克蛋白70(Highly sensitive person70,HSP70)、白细胞介素-6(Interleukin-6,IL-6)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)及肠道菌群16S rDNA,评价复方中药缓解热应激效果。结果表明,与热应激对照组相比,复方中药组在1~7 d、8~14 d和15~21 d,日均采食量极显著增加(P<0.01);复方中药组粪料比极显著降低(P<0.01)。肠道排空时间极显著减少(P<0.01);产蛋率在1~7d极显著升高(P<0.01),在8~14 d和15~21 d显著升高(P<0.05);脾脏指数显著升高(P<0.05);GSH-Px、T-SOD活力极显著升高(P<0.01),MDA含量极显著降低(P<0.01);IL-6、TNF-α含量极显著降低(P<0.01)。肠道菌群16S rDNA检测显示,在门水平上,拟杆菌门(Bacteroides)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)为优势菌门。可知,复方中药干预产蛋鸡热应激可缓解产蛋性能下降,虽低于正常组,但差异不显著。其主要作用是通过加快胃肠排空时间,提高抗炎、抗应激作用及拟杆菌、厚壁菌等优势菌群占比,缓解由热应激导致的蛋鸡采食量下降和热应激造成的机体损伤,改善因热应激导致的肠道益生菌群丰度失衡。

Heat stress is the main factor for the decline of livestock and poultry breeding performance in summer. In order to investigate the effect of compound Chinese medicine on the performance of poultry under heat stress, 60 85-week-old Hy-Line Brown layers were randomly divided into the normal control group, the heat stress control group, and the compound Chinese medicine group, and the experiment was performed for 21 d. The temperature of the normal control group was controlled at 25-28 ℃ and the humidity was 40% throughout the day;the heat stress control group and the compound Chinese medicine group were illuminated for 10 h per day, the temperature was controlled at 30-37 ℃ and the humidity was 55%, and the temperature and humidity control at the other times were the same as the normal control group. The diet of compound Chinese medicine group was supplemented with 1% compound Chinese medicine. The experiment evaluated the effect of compound Chinese medicine on relieving heat stress by detecting daily feed intake, manure ratio,intestinal emptying time, spleen index, egg production rate, glutathione peroxidase(GSH-Px),superoxide dismutase(SOD), malondialdehyde(MDA), heat shock protein 70(HSP70), interleukin-6(IL-6), tumor necrosis factor-α(TNF-α) and intestinal bacteria 16 S rDNA in laying hens. The results showed that compared with the heat stress control group, the average daily feed intake of compound Chinese medicine group increased significantly at 1-7 d, 8-14 d and 15-21 d(P<0.01). The ratio of manure in the compound Chinese medicine group was extremely significant decreased(P<0.01).Intestinal emptying time was extremely significant reduced(P<0.01). Egg production rate was extremely significant increased at 1-7 d(P<0.01), significantly increased at 8-14 d and 15-21 d(P<0.05);spleen index was significantly increased(P<0.05);the activities of GSH-Px and T-SOD were extremely significant increased(P<0.01), the content of MDA was extremely significant decreased(P<0.01), and the contents of IL-6 and TNF-α were extremely significant decreased(P<0.01). Intestinal bacteria 16S rDNA detection showed that Bacteroides, Firmicutes and Proteobacteria were the dominant bacteria at the phylum level. It concluded that compound Chinese medicine could alleviate the decrease of egg laying performance in laying hens with heat stress, although it was lower than that in the normal group, the difference was not significant. Its main role was to alleviate the decreased feed intake of laying hens caused by heat stress and the body damage caused by heat stress by accelerating the gastrointestinal emptying time, increasing the proportion of dominant bacteria such as bacteria, anti-stress effect and Bacteroides and Firmicutes, and improve the imbalance of intestinal probiotic flora abundance caused by heat stress.