Analysis of microbial diversity in rectum of calf in largescale cattle farm

Abstract:

Abstract:［Objective］ To analyze the diversity of bacterial community in rectum of diarrheic calves，and differences with health calves．［Methods］16S rRNA clone libraries were constructed，positive clones were digested by Msp I and Hha I for restriction fragment length polymorphism (RFLP) ，and then a phylogenetic tree was depicted based on the 16S rRNA sequencing，to confirm the compose of microbe in the diarrheic calf rectum．［Results］ The positive rate of clone was 98. 75% (474/480) in diarrheic calves，the dominant bacteria included Lactobacillus (14%)，Enterococcus (10%) and Escherichia (8%)． The positive rate of clone was 96. 45% (488/506) in health samples，the dominant bacteria included Clostridium (13%)，Bifidobacterium (8%)，Megasphaera (5%)．［Conclusion］Complexity and diversity of bacterial community in rectum in 2 weeks old calves had their own features，and significant increase of Lactobacillus，Enterococcus and Escherichia was found in diarrhea calves．

Key words:Keywords: calf rectum，microbial diversity，RFLP，16S rRNA sequence