Evaluation of dietary inclusion of housefly maggot ( Musca domestica ) meal on growth, fillet composition and physiological responses for barramundi, Lates calcarifer

Abstract

The study was to evaluate the effects of dietary fish meal (FM) partially replaced by housefly maggot meal (HMM) on growth, fillet composition and physiological responses of juvenile barramundi, Lates calcarifera. HMM at 100, 150, 200 and 300 g kg−1 was supplemented in the basal diet to replace dietary FM protein. Basal diet without HMM supplementation was used as control. Total of five experimental diets were fed to triplicate groups of juvenile barramundi (initial weight: 9.66 ± 0.22 g) in a flow-through rearing system for 8 weeks. Fish fed all experimental diets showed no effects (P > 0.05) on weight gain and whole body protein, lipid and moisture content. Fish fed control diet and 100 g kg−1 HMM diet had the highest (P < 0.05) hepatic superoxide dismutase (SOD) activity, followed by 150 g kg−1 HMM group, the lowest in 200 and 200 g kg−1 HMM groups. Hepatic thiobarbituric acid reactive substance (TBARS) value was the highest in fish fed 150–300 g kg−1 HMM diets, followed by 100 g kg−1 HMM group and the lowest in fish fed the control diet. Fish fed the 300 g kg−1 HMM diet had lower plasma lysozyme activity than fish fed other diets. The results indicated that up to 300 g kg−1 HMM can be used to substitute dietary FM protein without negative effect on growth. Although physiological responses were also considered, up to 100 g kg−1 HMM in barramundi diet was recommended.