Histomorphologic hepatic features and growth performances of juvenile Senegalese sole (Solea senegalensis) fed isogenertic practical diets with variable protein/lipid levels

Histological and morphometric techniques were employed in juvenile Senegalese sole (Solea senegalensis) livers to evaluate diet‐related adaptive changes and to establish how an integrated morphofunctional approach could improve the understanding of rearing strategies. Four isoenergetic diets with variable protein/lipid content (44/22, 49/20, 54/18 and 59/16) were formulated. Data compared statistically showed that an increase in protein and decrease of lipid in the diet was associated with a significantly higher specific growth rate (SGR) and reduced feed conversion rate (FCR). Histologic evaluation (visual scoring of lipid storage) and morphometry (area and perimeter) of hepatocytes showed that a high lipid diet resulted in increased lipid storage. The data confirmed that a concomitant decrease of protein with an increase in lipids in the diet led to a massive storage of unused lipid within hepatocytes associated with a reduced growth performance.