Dynamics and Diversity of Intrauterine Anaerobic Microbiota in Dairy Cows with Clinical and Subclinical Endometritis

SIMPLE SUMMARY: Research on uterine bacterial communities in diseased and healthy animals is crucial for a better understanding of the development of uterine diseases. Therefore, the objective of the study was to characterize the dynamics of anaerobic cultivable microbiota in the uterus of dairy cows. Sampling of 122 dairy cows at six time points after calving resulted in 1858 bacterial isolates. Remarkable shifts were observed in the composition of microbiota throughout the postpartum period, whereas some bacteria were associated with endometritis, and some were frequently detected in healthy animals. This study provides information for the development of novel prevention and therapeutic strategies. ABSTRACT: The aim of the study was to characterize the dynamics of anaerobic cultivable postpartum microbiota in the uterus of dairy cows. In total, 122 dairy cows were enrolled and sampled on day 0 (day of calving) and on days 3, 9, 15, 21, and 28 postpartum (pp). Samples were cultivated anaerobically and analyzed by MALDI-TOF MS. In total, 1858 isolates were recovered. The most prevalent facultative anaerobic genera were Trueperella (27.8%), Streptococcus (25.4%), and Escherichia (13.1%). The most prevalent obligate anaerobes were Peptoniphilus (9.3%), Bacteroides (3.3%), and Clostridium (2.4%). The microbial communities were highly dynamic and diverse. On the animal level, Trueperella pyogenes on day 21 and 28 pp was associated with clinical endometritis, and E. coli on day 21 pp was associated with subclinical endometritis. The occurrence of Streptococcus pluranimalium on day 28 was related to uterine health. The presence of T. pyogenes, Streptococcus, and Peptoniphilus was significantly associated with an increased risk for purulent vaginal discharge. Primiparous cows showed a higher prevalence of T. pyogenes, Fusobacterium necrophorum, Porphyromonas levii, and Peptoniphilus spp. than multiparous cows but were not more susceptible to uterine diseases. This study might provide a suitable basis for future co-cultivation studies to elucidate potential synergistic interactions between microbiota.