中国农业科学 ›› 2022, Vol. 55 ›› Issue (17): 3450-3460.doi: 10.3864/j.issn.0578-1752.2022.17.015

• 畜牧·兽医 • 上一篇    下一篇

热应激对肉鸡回肠菌群的影响因素研究

王雪洁(),邢爽(),赵少猛,周莹,厉秀梅,柳清秀,马丹丹,张敏红,冯京海()   

  1. 中国农业科学院北京畜牧兽医研究所/动物营养学国家重点实验室,北京 100193
  • 收稿日期:2021-07-25 接受日期:2022-07-13 出版日期:2022-09-01 发布日期:2022-09-07
  • 通讯作者: 冯京海
  • 作者简介:王雪洁,E-mail: 927683542@qq.com。|邢爽,E-mail: 1194325185@qq.com
  • 基金资助:
    国家重点研究发展计划(2016YFD0500509);中国农业科学院科技创新工程(ASTIP-IAS07)

Effects of Heat Stress on Ileal Microbiota of Broilers

WANG XueJie(),XING Shuang(),ZHAO ShaoMeng,ZHOU Ying,LI XiuMei,LIU QingXiu,MA DanDan,ZHANG MinHong,FENG JingHai()   

  1. Institute of Animal Sciences, Chinese Academy of Agricultural Sciences/State Key Laboratory of Animal Nutrition, Beijing 100193
  • Received:2021-07-25 Accepted:2022-07-13 Online:2022-09-01 Published:2022-09-07
  • Contact: JingHai FENG

摘要:

【目的】 探究热应激如何影响肉鸡的肠道微生物组成和结构,为研究缓解热应激的不利影响提供依据。【方法】 将144羽体重接近(1 771±40)g的35日龄AA雄性肉鸡随机分为3个处理组。3个处理组分别为适温对照组(TC)、高温组(HT)和适温采食配对组(PF)。TC组舱内温度维持(21±1)℃,肉鸡自由采食;HT组舱内温度维持(31±1)℃,自由采食;PF组舱内温度维持(21±1)℃,根据HT肉鸡的采食量饲喂。温度及限饲处理共持续7 d。【结果】 研究发现,与TC组相比,HT组肉鸡的采食量和日增重显著降低(P<0.01),料重比显著提高(P<0.01),PF组肉鸡采食量和日增重显著降低(P<0.01)。HT组的采食量与PF组相似,但日增重显著低于PF组(P<0.05),料重比高于PF组(P<0.05)。表明即使采食量相同,高温仍显著降低肉鸡体增重,这与高温降低饲料转化效率有关。与TC组相比,HT组肉鸡的体核温度(P=0.079)和血清皮质酮水平(P=0.071)有升高趋势,PF组肉鸡体核温度和血清皮质酮水平与TC组相似(P>0.05)。与TC组相比,HT组和PF组肉鸡回肠前段菌群sobs、Chao1和Shannon指数均显著升高(P<0.05),而HT组和PF组的α多样性指数无显著性差异。主坐标分析(PCoA)显示,HT组和PF组基本聚集在一起,与TC组有明显的分离。相似性分析也证实了这一趋势。相关分析发现,肉鸡的采食量和PCoA的主坐标1之间存在显著相关(R = 0.786, P<0.001),而肉鸡体核温度或血清皮质酮和主坐标1之间无显著相关(P>0.05)。LEfSe分析发现(Score ≥3),HT组和TC组之间存在18个特异属。PF组肉鸡回肠中这18个属的相对丰度与HT组接近,与TC组同样存在显著差异。另外,回肠前段优势菌属中(TOP50),采食量与其中30个属的相对丰度显著相关,而体核温度和血清皮质酮仅与其中个别属的相对丰度相关。【结论】 HT组与PF组肉鸡的体核温度和血清皮质酮存在明显差异,但采食量相同,结果回肠菌群的结构和组成相似;TC组与PF组肉鸡的体核温度和血清皮质酮相似,仅采食量显著不同,结果回肠菌群的结构和组成明显不同。表明持续热应激对肉鸡回肠前段菌群的影响主要与采食量降低有关,与体温或血清皮质酮升高无显著关系。相关分析的结果也证明了这一结论。

关键词: 热应激, 肉鸡, 回肠, 微生物菌群, 采食量

Abstract:

【Objective】 To explore how heat stress influences the composition and structure of intestinal microbiota in broilers, and to provide a basis for alleviating the adverse effects of heat stress. 【Method】 144 broilers ((1 771±40) g, 35 d) were randomly divided into three groups with six replicates and raised in three controlled climate chambers from 35 to 42 days in this study. They were allocated to one of a thermoneutral control group (TC, 21℃, ad libitum), a heat stress group (HT, 31℃, ad libitum), or a pair-feeding group(PF, 21℃, pair-feeding as much as the consumption of the HT birds). 【Result】 Compared with broilers in TC, the feed intake and body weight gain were significantly decreased and F/G was increased in broilers of HT (P<0.01), the feed intake and body weight gain were also significantly decreased in broilers of PF (P<0.01). The feed intake of broilers in HT was as same as it in PF, but the body weight gain in HT was lower than it in PF, and the F/G was higher (P<0.05), which indicated that the heat stress still decreased the body weight gain of broilers even at the same level of feed intake. Compared with broilers in TC, the core temperature (P=0.079) and serum corticosterone content (P=0.071) have an increasing tendency in broilers of HT, and have similar levels in PF (P>0.05). The richness of species(sobs and Chao1)and diversity indices(Shannon)of samples in the HT and PF group were higher than those in the TC group (P<0.05). There was no significant difference in terms of the diversity estimators of the ileal microbiota between the HT and the PF groups. The PCoA showed that the HT and PF groups were gathered together but were distinctly separated from the TC group. This tendency was also verified by the similarity analysis. Moreover, the feed consumption was significantly correlated with the principal coordinate 1 in the PCoA (R = 0.786, P<0.001), but the body temperature or the serum corticosterone was not correlated with the principal coordinate 1 (P>0.05). Furthermore, 18 differential genera between the HTG and the TC groups were identified by LEfSe analysis (score ≥ 3). The relative abundance of these genera in the PF and HT groups was similar but had significant differences compared with that in the TC group. In addition, among the 50 most abundant genera in the ileal microbiota, the feed consumption was significantly correlated with 30 genera, but the body temperature and serum corticosterone were significantly correlated with only two and no genera, respectively. 【Conclusion】 The core temperature and serum corticosterone content were different, the feed intake was similar between HT and PF, and the composition and community structure of ileal microbiota were similar between those two groups; the core temperature and serum corticosterone content were similar, but the feed intake was different between TC and PF, and the composition and community structure of ileal microbiota were also different between those two groups, these results indicate that the effects of constant heat stress on composition and community structure of ileal microbiota in broilers are related to reduced feed consumption. This conclusion was also proved by the results of correlation analysis.

Key words: heat stress, broilers, ileum, microbiota, feed consumption