不同生理阶段荷斯坦奶牛瘤胃细菌多样性研究

Rumen Bacteria Diversity in Holstein Dairy Cows at Different Physiological Phases

本试验旨在探究不同生理阶段荷斯坦奶牛瘤胃细菌多样性。选取处于围产前期、泌乳前期、泌乳中期和泌乳后期的经产荷斯坦奶牛各4头,共16头,采集瘤胃液用于测定瘤胃发酵参数和提取微生物DNA,采用Illumina Miseq PE300平台测定瘤胃细菌组成。结果表明:1)围产前期奶牛瘤胃微生物蛋白、乙酸、丁酸、总挥发性脂肪酸浓度与乙酸/丙酸显著高于泌乳期(P<0.05)。围产前期奶牛瘤胃丙酸浓度显著低于泌乳期(P<0.05)。2)在门的水平上,围产前期奶牛瘤胃内的优势菌门为拟杆菌门和厚壁菌门,泌乳期奶牛瘤胃内的优势菌门则为拟杆菌门、变形菌门和厚壁菌门。围产前期奶牛瘤胃内的拟杆菌门、SR1细菌、蓝菌门、柔膜菌门、TM7细菌和纤维杆菌门的相对丰度显著高于泌乳期(P<0.05),而泌乳期各阶段之间差异不显著(P>0.05);围产前期奶牛瘤胃内的变形菌门的相对丰度显著低于泌乳期(P<0.05)。3)在科的水平上,围产前期奶牛瘤胃内的优势菌科为普雷沃氏菌科,而泌乳期奶牛瘤胃内的优势菌科为琥珀酸弧菌科和普雷沃氏菌科。围产前期奶牛瘤胃内的普雷沃氏菌科、瘤胃菌科、理研菌科、BS11细菌、RF16细菌、SR1细菌、Gastranaerophilales、克里斯滕森菌科、TM7细菌、RF9细菌和纤维杆菌科的相对丰度显著高于泌乳期(P<0.05);围产前期奶牛瘤胃内的琥珀酸弧菌科、毛螺菌科和韦荣球菌科则显著低于泌乳期(P<0.05)。综上得出,奶牛从围产前期进入到泌乳期,瘤胃细菌多样性显著降低;泌乳期各阶段瘤胃细菌组成差异较小。

This study aimed at investigating the rumen bacterial diversity in Holstein dairy cows at different physiological phases. Sixteen cows were chose and divided into 4 groups according to their physiological phases which were early prenatal phase, early lactation phase, medium lactation phase and late lactation phase. Collecting the fluid phase of ruminal fluid to determined the rumen fermentation parameters and extracted the rumen microbial DNA. The Illumina Miseq PE300 platform was used to determine the rumen bacterial composition. The results showed as follows： 1） the concentrations of microbial protein, acetic acid, butyric acid and total volatile fatty acid and acetic acid/propionic acid in rumen of cows in early prenatal phase were significantly higher than those in lactation phase （ P 〈0.05）, the rumen propionic acid concentration cows in early prenatal phase was significantly lower than that in lactation phase （ P 〈0.05）. 2） At the level of phyla, the dominant bacteria in rumen of cows in early prenatal phase were Bacteroides and Firmicutes, the dominant bacteria in rumen of cows in lactation phase were Bacteroidetes, Proteobacteria and Firmicutes. The relative abundances of Bacteroidetes, SR1 bacteria, Cyanobacteria, TM7 bacteria, and Fibrobacter in rumen of cows in early prenatal phase were significantly higher than those in lactation phase （ P 〈0.05）, while there was no significant difference among all lactation phases （ P 〉0.05）. In contrast, the relative abundance of Proteobacteria in rumen of cows in early prenatal phase was significantly lower than that in lactation phase （ P 〈0.05）. 3）. At the level of family, the dominant bacteria in rumen of cows in early prenatal phase were Prevotellaceae, while the dominant bacteria in rumen of cows in lactation phase were Succinivibrionaceae and Prevotellaceae. The relative abundances of Prevotella, Ruminococcaceae, Rikenellaceae, BS11 bacteria, RF16 bacteria, SR1 bacteria, Gastranaerophilales, Christensenellaceae, TM7 bacteria, RF9 bacteria and Fibrobacteria in rumen of cows in early prenatal phase were significantly higher than those in lactation phase （ P 〈0.05）. The relative abundances of Succinivibrionaceae, Lachnospiraceae and Veillonellaceae in rumen of cows in early prenatal phase were significantly lower than those in lactation phase （ P 〈0.05）. In conclusion, the diversity of rumen bacteria in dairy cows significantly decrease from early prenatal phase to lactation phase, but there is little difference in the composition of rumen bacteria among all lactation phases.