Characteristics of reproductive tract microbiota in health and disease.

The symbiotic relationship between the microbiota and the host is crucial to host health. The reproductive tract microbiota in health and disease was examined by next-generation sequencing for the first time in this study. A total of 10 healthy and 30 diseased samples were collected for microbiota analysis. Species distributions, alpha diversity, beta diversity, and functional gene prediction were analyzed. Riemerella anatipestifer, Escherichia coli, Avibacterium paragallinarum, Ornithobacterium rhinotracheale, Enterococcus faecalis, and Acinetobacter baumannii were identified as pathogenic bacteria at higher abundance in the reproductive tract of the laying hens. The diseased group exhibited dysbacteriosis and a different species-abundance cluster compared with the healthy control. Alpha-diversity analysis showed that the ACE index in the control group was significantly higher than in the diseased group. Beta diversity analysis indicates that samples from the healthy group had a more similar composition than those from the diseased group. Moreover, functional gene prediction analysis indicated that diseased groups were enriched for gram-negative, facultative anaerobic, and potentially pathogenic bacteria. The pathogenic bacteria identified in this study are helpful for vaccine development and disease treatment. In conclusion, next-generation sequencing is an effective method for analyzing bacterial communities to support health assessment and disease diagnosis.