Impact of weaning age on gut microbiota composition in piglets

F.R. Massacci et al., 69th Annual meeting of the european federation of animal science (EAAP), Dubrovnik, Croatie, 27-31 août 2018

Weaning is a crucial period of pigs, accompanied by nutritional, environmental and social stresses. Studies comparing different ages at weaning have shown that increasing weaning age improves wean-to-finish growth performances and reduces mortality. However, the impact of weaning age on the early-life establishment of the gut microbiota remains under-investigated in pigs. Our objective was to compare the gut microbiota composition of piglets weaned at different ages. 48 piglets were divided in 4 groups of 12 animals weaned at either 14, 21, 28 or 42 days-of-age.
Faecal samples were collected at 3 different time points: day of weaning, 7 days after weaning and at 60 days of age. Faecal DNA bacterial composition was assessed by sequencing the V3-V4 regions of the 16S rRNA gene.
Bioinformatic and biostatistical analysis showed that each weaned group had significant differences between the sample points through weaning transition, confirming that the gut microbiota changes before and after weaning. In addition, microbiota diversity increased according to weaning age, with piglets weaned at 42 days-of-age having a highest alpha diversity and richness. Interestingly, piglets weaned at 42-days maintained a more stable diversity until day 60. We show that late weaning leads to a higher diversity of potentially beneficial microbes prior to the crucial challenge of weaning and might thus provide a competitive advantage to piglets.