Intermittent feeding induces compensatory growth of juvenile yellow mystus (Hemibagrus nemurus)

Abstract

Cyclical starvation and refeeding in order to induce compensatory growth were investigated in juvenile yellow mystus (Hemibagrus nemurus). The fish (7.12 ± 0.14 g initial body weight and 8.87 ± 0.04 cm initial length) were starved for one (1DPW), two (2DPW), three (3DPW) or four (4DPW) days per week and otherwise fed ad libitum, while the control group was fed every day (no starvation, 0DPW). The indoor experiments lasted six weeks and followed a completely randomized design (5 treatments × 3 replications × 10 fish per replication). Growth performance, feed utilization, specific activity of digestive enzymes, carcass composition and muscle quality were used to compare the treatment effects. The fish in the 3DPW group exhibited clear compensation for the reduced number of feeding days and had increased body weight towards the end of the experiment. However, this compensation was insufficient to match the specific growth rate in the control group that was fed to satiation daily. The 3DPW treatment also maintained feed utilization parameters, specific activities of protein-, carbohydrate- and lipid-digesting enzymes, carcass composition and muscle quality, relative to the 0DPW control group. The remaining treatments gave some inferior characteristics when compared to 3DPW and 0DPW; the ranking of these feeding treatments was unexpected within the studied period. These findings suggest that cyclical starvation for three days per week (3DPW treatment) and refeeding could be used for rearing juvenile yellow mystus. The intermittent feeding schedule scheme is useful for labor management in the aquaculture production of yellow mystus. However, since partial compensatory growth was observed in the 2DPW and 4DPW groups, as indicated by the compensation coefficient, prolonged experiments on the accelerated growth rate should be conducted in further studies.