Characterization of the intestinal microbiota and metabolic pathways in sows with and without stillbirths: a study from a commercial pig farm in southern Brazil.

Reproductive diseases in swine are responsible for important losses in pig farming. Within this context, stillbirth is one of the major causes of productive losses and sow culling. This is a complex condition, in which definitive diagnosis is difficult due to a plurality of associated factors. The maternal intestinal microbiota has been gaining attention, but there are still a low number of studies on this subject. In the present study the intestinal bacterial microbiota and its metabolic pathways were assessed in 68 sows with (n = 36) and without (n = 32) stillbirths from a farrowing-to-wean commercial pig farm from Southern Brazil. Some opportunistic pathogens were enriched in the stillbirths' group such as bacteria from the genera Odoribacter and UCG-001; while in the group without stillbirths, bacteria from the family Oscillospiraceae and the genus Faecalibacterium were enriched; these bacteria are candidates for next generation probiotics in humans, making them also promising for future studies with probiotics in swine farming. Moreover, two metabolic pathways were inferred as enriched, one in each group, both related to the maintenance of the bacterial cell wall, with no obvious association with the occurrence of stillbirths. The data obtained in the present study characterized the intestinal microbiota of sows in the studied region, allowing a better understanding of their importance in animal health.