日粮中添加不同比例微贮棉秆对湖羊瘤胃微生物区系的影响

Effect of different proportions fermented cotton stalk intake on rumen microflora of lambs

摘要:

[目的] 本试验旨在利用16S rDNA高通量测序技术研究不同比例微贮棉秆的添加对断奶湖羊瘤胃微生物区系的影响。[方法] 选择日龄相近、体重相似的湖羊30只，根据日粮中微贮棉秆的含量随机分为3组：对照组（S0）、50%微贮棉秆组（S50）和100%微贮棉秆组（S100），每组随机屠宰6只分析生长性能，并取瘤胃液进行瘤胃发酵参数和微生物区系分析。[结果] 饲喂50%微贮棉秆能够显著提高湖羊日增重和屠宰率（P<0.05）。Bacteroidetes和Firmicutes是湖羊瘤胃的优势菌门，Prevotella和Unclassified Bacteroidales是湖羊瘤胃的优势菌属。日粮中添加100%微贮棉秆可以显著降低湖羊瘤胃菌群的多样性（P<0.05）；显著降低Unclassified Bacteroidales和BF311的相对丰度（P<0.05）。三条代谢通路甜菜素生物合成、吲哚生物碱生物合成和加压素调节水的重吸收随着微贮棉秆比例升高而显著增加（P<0.05）。[结论] 饲喂50%微贮棉秆在提高日增重的同时对湖羊瘤胃微生物菌群结构与功能影响较小。在生产实践中，微贮秸秆添加量应低于50%。

Abstract:

[Objective] The objective of this study was to assess the effect of fermented cotton stalk in the diet on rumen microflora of weaned lambs by using high-throughput sequencing technology.[Methods] Thirty Hu sheep were selected and randomly divided into three groups according to different proportions of fermented cotton stalk in the diet:the control (S0), 50% fermented cotton stalk (S50) and 100% fermented cotton stalk (S100), six sheep were randomly slaughtered in each group to analyze their growth performance, rumen fermentation parameters and microflora analysis.[Results] Feeding 50% fermented cotton stalk can significantly improve the daily gain and slaughter rate of lambs (P<0.05). Bacteroidetes and Firmicutes are the dominant phylum in the rumen, Prevotella and Unclassified Bacteroidales are the dominant genus of the rumen of the lambs. Adding 100% fermented cotton stalk to the diet could significantly reduce both the diversity of rumen microflora and the relative abundance of Unclassified Bacteroides and BF311 (P<0.05). Three metabolic pathways significantly increased as the proportion of fermented cotton stalk increased (P<0.05).[Conclusion] Feeding 50% fermented cotton stalk had little effect on the structure and function of rumen microflora while increasing daily weight. In production practice, the content of fermented stalk should be lower than 50%.