Changes in growth, orexigenic hormones and blood metabolites following short‐term food deprivation and refeeding in juvenile Asian sea bass (Lates calcarifer)

Abstract

Changes in growth, blood metabolites and blood ghrelin and leptin levels were investigated in Asian sea bass (Lates calcarifer) subjected to short-term food deprivation and refeeding. After two weeks of acclimation, 144 fish, weighing 35 ± 5 g, were randomly assigned to twelve 300-litre polyethylene tanks and were fed to satiation twice daily (10:00a.m. and 17:00pm) using a commercial diet for 24 days. The experimental design included four treatments with three replicates each: 2, 4 and 8 days food deprivation followed by 16 days refeeding and a control group without food deprivation. Growth parameters did not show any significant change at the end of the experiment. Plasma ghrelin levels increased significantly after 4 and 8 days food deprivation (p ˂ .05). Food deprivation resulted in lower plasma leptin levels whereas refeeding led to an increase in leptin. No significant difference in leptin levels was observed between the treatments. An increase in triglyceride and a decrease in blood glucose levels were observed during the fasting period. At the end of refeeding period, the plasma protein did not show any significant variation among the treatments. Our results demonstrate the ability of L. calcarifer juveniles to adapt well to food supply after a period of food deprivation which could be associated with the status of appetite-regulating hormones such as ghrelin and leptin.