Francois-Etienne Sylvain
Laval University, Canada
Title: You are what you eat: Get mature faster by foraging on your parents, the discus fish example
Biography
Biography: Francois-Etienne Sylvain
Abstract
The Discus fish (Symphysodon aequifasciata) is an Amazonian ornamental fish with a unique parental behaviour. After hatching, the fry feeds exclusively on a cutaneous mucus secretion from both parents during three weeks. Studies have documented a differential protein pattern on the mucus layer of discus in reproductive phase, suggesting that specific elements are vertically transferred from parents to their offspring to stimulate fry growth. The aims of our study were (1) to characterize the ontogenesis of discus fish gut microbiota; (2) to determine if reproduction phase induced a differential shift of cutaneous mucus microbiota composition on parental fish; and (3) to assess the impact of parental feeding on the compositional dynamics of discus fry gut microbiota. To achieve these goals, we sampled thoroughly one brood of S. aequifasciata, during four months post-hatch. We sampled fry and parental feces, parental mucus and aquarium water. We sequenced the hypervariable region V4 of the rRNA 16S to characterize bacterial communities in all samples. The results show that (1) there is a convergence of the gut microbiota composition of the fry towards the gut microbiota of their parents as soon as the fry starts feeding on their parents cutaneous mucus; (2) there is a differential shift of the parental mucus microbiota composition when the parents get in reproductive phase; and (3) the taxonomic structure of the fry gut microbiota stabilizes earlier than what has been observed for the shorter-lived zebrafish. Our results highlight the beneficial influence of vertical parent-offspring transfer of parental bacteria via skin mucus feeding.