红豆草茬地放牧对湖羊和小尾寒羊生长性能、瘤胃内环境参数及微生物区系的影响

Effects of Grazing on Stubble Sainfoin Pasture on Growth Performance,Rumen Environmental Parameters and Microflora of Hu Sheep and Small-Tailed Han Sheep

本试验以空怀期湖羊和小尾寒羊为研究对象,分析在红豆草茬地放牧条件下其生长性能、瘤胃内环境参数及瘤胃微生物区系之间的差异,以期为不同品种放牧绵羊对红豆草茬地的响应情况积累数据,进而为陇中地区草地生产系统的科学管理提供技术支持。选择年龄一致、体况良好的空怀期湖羊[平均体重(31.95±1.60)kg]和小尾寒羊[平均体重(27.38±2.84)kg]各24只为试验动物,于红豆草二茬草地进行为期45 d的混群放牧试验,试验期间测定动物体重并采集瘤胃液用于瘤胃内环境参数和瘤胃微生物区系分析。结果表明:1)湖羊组始重和末重显著高于小尾寒羊组(P<0.05),但平均日增重和体重增长率显著低于小尾寒羊组(P<0.05)。2)小尾寒羊组瘤胃总挥发性脂肪酸含量显著高于湖羊组(P<0.05)。3)小尾寒羊组瘤胃微生物Shannon指数显著高于湖羊组(P<0.05),Simpson指数显著低于湖羊组(P<0.05)。4)在门水平上,湖羊组的优势菌门依次为变形菌门(58.81%)、拟杆菌门(17.21%)和厚壁菌门(16.09%),而小尾寒羊组的优势菌门依次为厚壁菌门(36.52%)、拟杆菌门(36.00%)和变形菌门(5.97%)。小尾寒羊组瘤胃中拟杆菌门和厚壁菌门相对丰度显著高于湖羊组(P<0.05),但变形菌门相对丰度显著低于湖羊组(P<0.05)。5)功能预测分析结果显示,湖羊组在疾病和抗生素合成通路的功能基因相对丰度显著高于小尾寒羊组(P<0.05)。由此可见,在红豆草茬地放牧条件下,湖羊和小尾寒羊对该饲养管理方式的响应情况不同,小尾寒羊生长性能、瘤胃内总挥发性脂肪酸含量及瘤胃内微生物多样性均高于湖羊,且湖羊和小尾寒羊瘤胃微生物群落结构和功能存在差异。

This experiment took non-pregnant Hu sheep and small-tailed Han sheep as the research objects,and analyzed the differences between their growth performance,rumen environment parameters and rumen microflora under grazing conditions of sainfoin stubble,with the aim of accumulating data for the response of different breed sheep grazing on the sainfoin stubble,and then provided technical support for the scientific management of the grassland production system in Longzhong region.Twenty-four non-pregnant Hu sheep[average body weight was(31.95±1.60)kg]and small-tailed Han sheep[average body weight was(27.38±2.84)kg]with the same age and good body condition were selected as the test animals,and a 45-day mixed grazing experiment was carried out on the stubble sainfoin pasture.During the experiment,the body weight of the animals was measured and the rumen fluid was collected for analysis the rumen environmental parameters and microflora.The results showed as follows:1)the initial body weight and final body weight of Hu sheep group were significantly higher than those of small-tailed Han sheep group(P<0.05),but the average daily gain and weight growth rate were significantly lower than those of small-tailed Han sheep group(P<0.05).2)The content of total volatile fatty acids in rumen of small-tailed Han sheep group was significantly higher than that of Hu sheep group(P<0.05).3)The rumen microbial Shannon index of small-tailed Han sheep group was significantly higher than that of Hu sheep group,and the Simpson index was significantly lower than that of Hu sheep group(P<0.05).4)At the phylum level,the dominant bacteria of Hu sheep group were Proteobacteria(58.81%),Bacteroidetes(17.21%)and Firmicutes(16.09%),while the dominant bacteria of small-tailed Han sheep group were Firmicutes(36.52%),Bacteroidetes(36.00%)and Proteobacteria(5.97%).The relative abundances of Bacteroidetes and Firmicutes in rumen of small-tailed Han sheep group were significantly higher than those of Hu sheep group(P<0.05),but the proteobacteria relative abundance was significantly lower than that of Hu sheep group(P<0.05).5)The function prediction analysis result showed that the relative abundances of functional genes in disease and antibiotic synthesis pathways of Hu sheep were significantly higher than those of small-tailed Han sheep(P<0.05).In conclusion,Hu sheep and smalltailed Han sheep respond differently under sainfoin stubble grazing conditions,the growth performance,rumen total volatile fatty acid content and rumen microbial diversity of small-tailed Han sheep are significantly higher than those of Hu sheep,and the structure and function of rumen microbial community of Hu sheep and smalltailed Han sheep are also different.