不同品种羔羊胃肠道微生物发育规律的比较研究

Comparative Studies on Developmental Patterns of GastrointestinalMicrobiota of Different Breed Lambs

本试验旨在探究相同饲养条件下不同品种(道赛特羊、湖羊和小尾寒羊)羔羊瘤胃和直肠的细菌和真菌差异,为阐明不同品种羔羊胃肠道微生物发育规律和精准饲养管理提供基础数据。选取同一产房、胎次和性别相同的1日龄不同品种羔羊30只,其中道赛特羊、湖羊和小尾寒羊公羔各10只,相同饲养管理模式下进行120 d饲养试验。采集瘤胃液和粪便样品,测定细菌和真菌区系。结果表明:1)小尾寒羊瘤胃细菌的PD whole tree指数显著高于湖羊(P<0.05),湖羊直肠真菌的辛普森指数显著高于道赛特羊(P<0.05)。2)主坐标分析(PCoA)和相似性分析(ANOSIM)表明,不同品种羔羊在20、90日龄瘤胃细菌,70日龄直肠细菌,20、70、90日龄瘤胃真菌,90、120日龄直肠真菌中的群落均存在显著差异(P<0.05)。3)道赛特羊直肠细菌中螺旋体门和密螺旋体属相对丰度表现出升高的趋势(P=0.086)。小尾寒羊瘤胃细菌中理研菌科RC-9肠道群和克里斯滕森菌科R-7群相对丰度显著高于道赛特羊和湖羊(P<0.05),瘤胃真菌中子囊菌门相对丰度显著低于道赛特羊和湖羊(P<0.05),瘤胃细菌中普雷沃氏菌属相对丰度表现出降低的趋势(P=0.063)。综上所述,在相同饲养条件下,3个品种羔羊的胃肠道菌群的多样性和组成均存在差异,小尾寒羊具有较高的瘤胃细菌多样性,湖羊具有较高的直肠真菌多样性,道赛特羊直肠细菌中螺旋体门和密螺旋体属相对丰度较高,小尾寒羊瘤胃细菌中普雷沃氏菌属相对丰度较低以及理研菌科RC-9肠道群和克里斯滕森菌科R-7群相对丰度较高,胃肠道微生物区系结构差异可能是导致不同品种羔羊生产性能差异的原因之一。

This experiment was conducted to investigate the differences of bacteria and fungi in the rumen and rectum of different breed lambs(Dorset lambs,Hu lambs and small tail Han lambs)under the same feeding conditions,to provide basic data for developmental patterns of gastrointestinal microbiota and precise feeding and management of different breed lambs.Thirty 1-day-old lambs with same fetal times and gender and born in the same maternity barn were selected,among them,there were 10 Dorset lambs,10 Hu lambs and 10 small tail Han lambs,feeding for 120 days under the same feeding management mode.Rumen fluid and feces were collected,to determine the bacterial and fungal flora.The results showed as follows:1)the PD whole tree index of rumen bacteria of small tail Han lambs was significantly higher than that of Hu sheep(P<0.05),and the Simpson index of rectal fungal of Hu sheep was significantly higher than that of Dorset lambs(P<0.05).2)The principal coordinates analysis(PCoA)and analysis of similarities(ANOSIM)showed that there were significant differences in the communities of rumen bacteria at 20 and 90 days of age,rectal bacteria at 70 days of age,rumen fungi at 20,70 and 90(P<0.05)days of age,and rectal fungi at 90 and 120 days of age among different breed lambs(P<0.05).3)The relative abundances of Spirochaetes and Treponema in rectal bacteria of Dorset lambs showed an increasing trend(P=0.086).The relative abundances of Rikenellaceae_RC-9_gut_group and Christensenellaceae_R-7_group in rumen bacteria of small tail Han lambs were significantly higher than those of Doset lambs and Hu lambs(P<0.05),the relative abundance of Ascomycetes in rumen fungi was significantly lower than that of Doset lambs and Hu lambs(P<0.05),and the relative abundance of Prevotella in rumen bacteria showed a lower trend(P=0.063).In conclusion,under the same feeding conditions,there are differences in the diversity and composition of gastrointestinal microbiota among the three breed lambs,the Small tail Han lambs have higher rumen bacterial diversity,the Hu lambs have higher rectal fungal diversity,the Dorset lambs have higher relative abundances of Spirochaetes and Treponema in rectal bacteria,the small tail Han lambs have lower relative abundance of Prevotella and higher relative abundances of Rikenellaceae_RC-9_gut_group and Christensenellaceae_R-7_group in rumen bacteria.The differences in the structure of gastrointestinal microbial flora might be one of the reasons for the differences in performance of different breed lambs.