养猪发酵床垫料不同时期碳氮和微生物群落结构变化研究

Change research of carbon,nitrogen and microbial community structure in different periods of fermentation bed for pig

该研究以短、长期养猪发酵床垫料为对象,采用16Sr RNA基因高通量测序技术研究垫料微生物的群落组成,分析细菌群落结构与垫料碳氮组成的相关性。结果表明:微生物发酵床优势菌为拟杆菌门、厚壁菌门、变形菌门和放线菌门。漠河杆菌属和梭菌属是垫料中相对丰度最高的物种。细菌群落多样性和主成分分(principal component analysis)析的结果表明:养殖时间一定程度上影响了发酵床垫料的微生物群落多样性和组成,但差异不显著。随着养殖时间的延长,在门水平上,放线菌门、绿弯菌门的细菌相对丰度显著增加,由21.3%、1.64%分别提高到28.4%和4.34%;在属水平上,甲基暖菌属、甲基杆菌属、马杜拉放线菌属、分枝杆菌属、红球菌属、副球菌属等11个物种相对丰度显著增加,甲基暖菌属、马杜拉放线菌属的相对丰度由0.405%、0.570%分别提高到2.862%、2.190%;假单孢菌属、嗜冷杆菌属、鞘氨醇杆菌属、黄杆菌属等7个物种显著降低,假单孢菌属、嗜冷杆菌属的相对丰度由2.51%、2.13%分别下降到0.93%、0.18%。硝态氮的含量显著增加,有机质、纤维素和木质素的含量显著降低。Mantel test分析的结果表明:垫料细菌群落与纤维素含量显著正相关(r=0.333,P=0.042)。Spearman相关性分析表明不动细菌属、假单胞菌属与纤维素、半纤维素和木质素含量显著正相关,Gelidibacter、嗜冷杆菌属与纤维素含量显著正相关。垫料纤维素是影响微生物发酵床细菌群落的重要因素。该研究可为发酵床初期选择垫料及不同垫料的合理配比,提高粪便原位转化效率提供参考。

In this study,16S rRNA gene high-throughput sequencing technology was used to elucidate bacterial community structure during short-term and long-term fermented litter.The correlation between the bacterial community structure and carbon,nitrogen composition of the mattress for pig raising was analyzed.The results showed that the dominant bacteria in the microbial fermentation bed were Proteobacteria,Firmicutes,Actinobacteria,Bacteroidetes etc..Moheibacter,and Clostridium were the most abundant genus in fermentation litter.The diversity of bacterial community and principal component analysis of samples in fermentation bed showed that the cultivation time affected the diversity and composition of microbial community to a certain extent,but the difference was not significant.With the prolongation of culture time,the relative abundance of Actinobacteria and Cholroflexi respectively increased from 21.3%and 1.64%to 28.4%and 4.34%at the phylum level significantly(P<0.05).At the genus level,the relative abundance of eleven species,including Methylocaldum,Methylobacter,Actinomadura,Mycobacterium,Rhodococcus,Paracoccus increased significantly.Also the relative abundance of Methylocaldum and Actinomadura increased from 0.405%、0.570%to 2.862%and 2.19%respectively.But for Pseudomona,Psychrobacter,Sphingobacterium,Flavobacterium and other species were decreased significantly,and the relative abundance of Pseudomonas and Psychrobacter decreased from 2.51%and 2.13%to 0.93%and 0.18%respectively.Nitrate nitrogen content increased significantly,while organic matter,cellulose and lignin content decreased significantly.Mantel test analysis showed that it was positively correlated with significance at P<0.05 between bacterial community and cellulose content(r=0.333).Spearman correlation analysis showed that Acinetobacter and Pseudomonas were positively correlated with cellulose,hemicellulose and lignin contents,while Gelidibacter and Pseudomonas were positively correlated with cellulose contents.Cellulose was an important factor affecting bacterial community in microbial fermentation bed.This study could provide a reference for choosing the appropriate proportion of the mattress and different mattress in the preparation period of fermentation bed,and improved the conversion efficiency of pig manure.