Comparison Of Vaginal Microbial Community Structure In Beef Cattle Of Luteal Phase And Follicular Phase

Vaginal flora play an important role in furious of cattle genital tract in many reports, but little attention is paid to vaginal microbial community structure in beef cattle. This study investigated the vaginal flora in luteal phase and follicular phase to analyze the change of bacterial diversity in different phases using PCR-DGGE and Real-time PCR. The results are as follows:The objective of this study was to identify the vaginal flora structure of beef cattle and compare the structures of beef between luteal phase and follicular phase by PCR-DGGE. Seven beef cattles were selected to collect vaginal swab samples from luteal phase and follicular phase.Total bacterial DNA was extracted and 16 S rDNA V3 region was amplified using nest PCR respectively. Then, PCR products were detected by DGGE. Subsequently, DNA fingerprinting of specific bands were cloned and sequenced. The bacterial species were identified by comparing the sequence with clone sequencing and the known one with BLAST. The vaginal flora structure between luteal phase and follicular phase were compared. The results indicated that vaginal flora in healthy beef cattle includes: Aerococcus vaginalis, Aerococcus viridans,Haemophilus somnus, Streptococcus pluranimalium, Psychrobacter marincola, Escherichia coli,Sphingomonas roseiflava etc.The vaginal micro flora structure of beef cattle between the luteal and follicular phase was evaluated using Real-time PCR to detect the main number of vaginal flora in two stages respectively. Vaginal swab samples from seven cattle were collected during the luteal and follicular phase. Total bacterial DNA was extracted by Real-time PCR. Following the DGGE cloned results, five specific bacteria species were selected, such as Escherichia coli,Sphingomonas, Streptococcus, Lactobacillus and Haemophilus somnus. The Real-time PCR was used to measure the quantity of the vaginal flora in the luteal and follicular phase respectively.The results indicated that there was no significant difference between the luteal phase and follicular phase in total bacteria species, Escherichia coli, Sphingomonas and Haemophilus somnus(P>0.05). However, the Streptococcus number was significantly higher in the luteal phase than that of follicular phase(P<0.01). Conversely, follicular phase Lactobacillus was significantly higher than in the luteal phase(P < 0.05). The current results indicates that beef cattle micro flora structure differ during the luteal phase and the follicular phase significantly.In conclusion, the present study demonstrated the change of bacterial diversity in vaginal ofluteal phase and follicular phase in beef cattle and their difference using PCR-DGGE and Real-time PCR. The results not only lay a foundation for clarify different stage of hormone can influence the microbial community structure, but also provide reference for the development of micro ecological probiotics.