Acute response of refeeding in tambaqui submitted to long-term fasting

ABSTRACT This study aimed evaluate energetic mobilization in tambaqui submitted to fasting, after a one-day refeeding. 120 tambaqui juveniles were distributed in 12 310L polyethylene boxes. Three treatments were evaluated: Control (14 days of feeding); Fasting for 14 days; and Refeeding (13 days fasting and one day of feedback). After the experimental period, the fish were anesthetized with eugenol for blood collection and serum and plasma were used to measure glucose, triglycerides, cholesterol and serum protein. Subsequently, fish were euthanized to remove liver and mesenteric fat and were used to determine hepatic glycogen and lipid and mesenteric fat index. The results were submitted to ANOVA and the means compared by Tukey test when statistical significance was observed (P <0.05). Glucose, triglycerides and serum protein decreased after fasting, differing statistically with the control. Refeeding resulted in the recovery of three blood indicators. Liver analysis shows glycogen was consumed intensely during fasting and partially recovered after refeeding, when compared to control group. The results obtained in this study suggest that the 14-day fast was not harmful to the fish and the tambaqui are able to quickly adjust their metabolism according to their nutritional status.