Nos membres rayonnent – Félicitations à Charles Drouin Johnson !

Nous sommes fiers de souligner la récente publication intitulée Advances in the proof of concept of feed restriction as a strategy to improve Arctic charr cultivation: insights on the role of dietary nucleotides and digestive plasticity in supporting growth, réalisée par Charles Drouin Johnson, membre de RAQ et professionnel de recherche au laboratoire de Nathalie Rose Le François au Biodôme de Montréal.

Cette contribution publiée dans le Canadian Journal of Zoology met en lumière la qualité de ses travaux et son engagement envers l’avancement des connaissances sur la biologie et l’amélioration des pratiques d’élevage de l’omble chevalier.

Le RAQ se réjouit de voir ses membres contribuer de manière aussi significative au rayonnement scientifique.

🎉 Bravo à Charles pour cette réalisation remarquable !

📖 Pour en lire plus sur sa publication

Abstract

The natural predispositions of Arctic charr (Salvelinus alpinus, Linnaeus 1758) a species associated to the Holarctic realm, to sustain and recover from extended periods of feed restriction and growth depression during the winter were cautiously explored in an aquaculture context. The degree to which a growth recovery is achieved upon refeeding, is governed by the timing and the intensity of the restriction and the coping mechanisms occurring under the rearing conditions provided. Advantages for aquaculture are reduced labor, feed and phosphorus load. We investigated the effect of 1) a pilot-scale cyclical restriction-refeeding sequence over three size classes (Pre-experiment) and 2) the inclusion of dietary nucleotides during recovery on growth and feeding metrics, and sustainable profitability value (Experiment). Despite a feed reduction of ~30%, no clear effects on growth were observed, translating in savings of 1.84 CAD per kg of produced fish. Incorporation of dietary nucleotides during the recovery phase resulted in improved growth and feed conversion efficiency and created an upward shift of digestive organs allometries. Nucleotides exclusion after sixty days, subsided all the above. Overall, feed restriction induced net positive outcomes that increased the sustainable profitability value of the feeding strategy. We suggest that severe restriction leading to low adiposity, and nucleotide supplementation are required for the full expression of compensatory growth in Arctic charr.