Abstract #23

# 23
Uterine microbiota from calving until establishment of metritis in dairy cows.
Soo Jin Jeon*2, Achilles Vieira-Neto1, Mohanathas Gobikrushanth2,6, Rodolfo Daetz2, Rodolfo Mingoti1, Ana Carolina Parize2, Sabrina Freitas2, Antonio Nelson da Costa5, Rodrigo Bicalho3, Svetlana Lima3, Kwang C. Jeong1,4, Klibs N. Galvão2, 1Department of Animal Sciences, University of Florida, Gainesville, FL, 2Department of Large Animal Clinical Sciences, University of Florida, Gainesville, FL, 3Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, NY, 4Emerging Pathogens Institute, University of Florida, Gainesville, FL, 5Departamento de Zootecnia, Universidade Federal do Ceará, Fortaleza, Ceara, Brazil, 6Department of Agricultural, Food and Nutritional Science, University of Alberta, Alberta, Canada.

Objective was to characterize the progression of uterine miocrobiota from calving until establishment of metritis. Uterine swabs were collected at 0 (20 min from calving), 2, 4, 6, and 8 d postpartum (DPP) from 92 cows. Twelve cows were diagnosed with metritis at 4, 6, or 8 DPP (6 ± 2 DPP), and 12 healthy cows were selected for comparison. Swabs (n = 72) collected at 0, 2, and 6 ± 2 DPP were used for metagenomic sequencing of 16S rRNA gene on the Illumina MiSeq platform. A heat map showed that uterine microbiota was established in cows shortly after calving. The microbiota changed rapidly from 0 to 6 ± 2 DPP by decreasing the abundance of Proteobacteria and increasing the abundance of Bacteroidetes and Fusobacteria. At 6 ± 2 DPP, abundance of Bacteroidetes was significantly higher in metritic cows than healthy cows (P < 0.01). Although most genera were shared, healthy and metritic cows could be discriminated based on relative abundance at 0, 2, and 6 ± 2 DPP using discriminant analysis (P < 0.01). Also, discriminant analysis showed that Bacteroides, Filifactor, Porphyromonas, Fusobacterium, and Arcanobacterium/Trueperella were important predictors of metritis. Furthermore, Bacteroides and Fusobacterium were significantly correlated with uterine discharge score (rs = 0.51 and rs = 0.49, respectively; P = 0.02). Likewise, at species level, Bacteroides heparinolyticus and Fusobacterium necrophorum were the main bacteria for the development of metritis because they were both prevalent (16.8% and 20.2% in metritic cows; 7.0% and 15.8% in healthy cows) and correlated with uterine discharge score (rs = 0.42 and rs = 0.42, respectively; P ≤ 0.05). In addition, there was a second (Fusobacterium gonidiaformans, Helcoccocus ovis, and Filifactor villosus) and third (Bacteroides pyogenes, Porphyromonas levii and others) line of bacteria that acted synergistically with the main bacteria causing metritis.

Key Words: dairy cow, metritis, 16S metagenomics