Effect of starvation and re-feeding on growth performance and content of plasma lipids, glucose and insulin in cultured juvenile Persian sturgeon (Acipenser persicus Borodin, 1897)

The effect of starvation and subsequent re-feeding to satiation on compensatory growth performance, insulin and blood serum values were investigated in juvenile Persian sturgeon (Acipencer persicus) with an average weight 108.04 +/- 0.28 g (mean +/- SEM) and in the same rearing condition over an 8-week period. Sturgeons were allocated to one of five feeding treatments: controls (C, continuous feeding), W1 (1 week starvation), W2 (2 weeks starvation), W3 (3 weeks starvation) and W4 (4 weeks starvation), followed by a single 4 weeks of re-feeding to satiation. Changes in growth performance and blood serum indices were examined at the end of weeks 4 and 8. Body weight, specific growth rate (SGR), condition factor (CF) and weight gain were determined to have significantly decreased during starvation. Fish starved for 1 week reached the same weight as the control fish after re-feeding for 4 weeks, indicating that complete compensatory growth occurred. Although the specific growth rate in W2, W3 and W4 fish was greater than that in the control fish after re-feeding, W2, W3 and W4 fish did not reach the same body weight as control fish at the end of re-feeding period, and showed partial compensation only. Blood plasma, glucose and insulin concentrations did not change significantly during starvation and re-feeding (P > 0.05). This suggests that sturgeon are able to maintain glycaemia during starvation, probably due to their non-carbohydrate dietary source. Plasma total lipid and triglyceride levels increased in starvation treatments, whereas the increases were significant only in W3 treatment (P < 0.05). After a 4-week re-feeding period, their levels decreased in comparison to the starvation periods. Increases in plasma total lipid and triglyceride levels appear to be due to their roles as preferred nutrients for mobilization in Persian sturgeon and the magnitude and duration of compensatory growth depended on the length of food deprivation.