日粮物理有效中性洗涤纤维对奶牛瘤胃细菌组成的影响

Effect of Dietary Physically Effective Neutral Detergent Fiber Contents on Rumen Bacterial Composition in Dairy Cows

研究日粮物理有效中性洗涤纤维(peNDF)含量对奶牛瘤胃细菌组成的影响,旨在为奶牛日粮配制提供依据。选取12头体重相近的2胎次荷斯坦奶牛(产奶量为33.0±1.7 kg/d、泌乳天数131±8 d),随机分为3组,分别饲喂日粮组成相同但peNDF_(8.0)水平为高(11.25%)、中(10.56%)、低(9.02%)的全混合日粮。试验期为25 d,其中前21 d为适应期,后4 d为采样期。利用高通量测序技术测定3种日粮条件下瘤胃细菌的多样性。结果表明,低peNDF_(8.0)组ACE指数有低于其它两组的趋势(P<0.10)。在门水平上,拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)为优势菌门,在属水平上,普雷沃氏菌(Prevotella)为优势菌属。BS11科在高peNDF_(8.0)组和中peNDF_(8.0)组显著高于低peNDF_(8.0)组(P<0.05)。综上所述,高精料日粮情况下,奶牛日粮中peNDF_(8.0)水平从9.02%上升至11.25%对瘤胃细菌群落的影响较小。

This experiment was carried out to investigate the effects of dietary physically effective neutral detergent fiber(peNDF)contents on rumen bacterial composition in dairy cows.Twelve healthy second-parity Holstein dairy cows(33.0±1.7 kg/d milk yield and 131±8 days in lactation)with similar body weight were divided into three groups,and fed diets with high(11.25%of DM),middle(10.56%),low(9.02%)peNDF_(8.0),respectively.The test period lasted for 25 days with the first 21 days for adaption and the last 4 days for various measurements.High-throughput sequencing technology was used to determine the bacteria diversity and community structure.Results showed the low peNDF_(8.0)group ACE tended to be lower than that of the other two groups(P<0.10).Bacteroidetes,Firmicutes,and Proteobacteria were dominant in all the samples at the phylum level,while Prevotella was dominant at the genus level among three groups.BS11 in the family level was significantly higher in high and middle peNDF_(8.0)groups than low peNDF_(8.0)group(P<0.05).In conclusion,the results indicate that the peNDF_(8.0)content in high concentrate diets for dairy cows has slight effect on rumen bacterial communities when it rises from 9.02%to 11.25%.