Sampling intestinal microbiota in growing pigs: evaluation of CapSa, an ingestible capsule

This study aims to investigate Capsa, an ingestible capsule designed to collect the contents of the small intestine as it passes through the gastrointestinal tract. Eight Swiss Large White pigs weighing between 52.5 and 71.3 kg were administered two capsules each and monitored for three days before euthanasia for post-mortem sampling. Samples were collected from six equally divided segments of the small intestine, along with separate sampling of the solid and liquid contents of each segment when feasible. Samples were also obtained from the large intestine and faeces to determine CapSa’s sampling location. Fifteen capsules were retrieved from faecal samples (93.75%), with 87.5% recovered on the first day post-administration. Only one capsule was not recovered. Comparative analysis of the bacterial composition of the capsules and post-mortem samples was conducted using a Permutational Multivariate Analysis of Variance (PERMANOVA) model (Adonis), with sample type as a factor. The results revealed significant differences in bacterial composition between capsules and samples from the large intestine and faeces (p < 0.01). However, no significant difference was observed between capsule content and the liquid and solid parts of the fourth segment of the small intestine (p > 0.05). This study provides evidence that CapSa can effectively sample the intestinal microbiota of the middle part of the small intestine in growing pigs.