Sows affect their piglets' faecal microbiota until fattening but not their Salmonella enterica shedding status.

Recent studies have shown that Salmonella shedding status affects sows' microbiota during gestation and that these modifications are reflected in the faecal microbiota of their piglets at weaning. The aims of this study were: 1) to evaluate the persistence, up to the fattening period, of the previously measured link between the microbiota of piglets and their mothers' Salmonella shedding status; and 2) measure the impact of the measured microbiota variations on their Salmonella excretion at this stage. To achieve this, 76 piglets born from 19 sows for which the faecal microbiota was previously documented, were selected in a multisite production system. The faecal matter of these swine was sampled after four weeks, at the fattening stage. The Salmonella shedding status and faecal microbiota of these animals were described using bacteriological and 16S rRNA gene amplicon sequencing, respectively. The piglet digestive microbiota association with the Salmonella shedding status of their sows did not persist after weaning and did not affect the risk of Salmonella excretion during fattening, while the birth mother still affected the microbiota of the swine at fattening. This supports the interest in sows as a target for potentially transferrable microbiota modifications.