ABSTRACT
This study was carried out to investigate the effect of different concentrations of garlic (Allium sativum L.) extract in fish diet on survival rate, digestive enzymes and some biochemical parameters of Mugil cephalus larvae. Three hundred and sixty fish with mean weight 0.45 g were randomly divided into equal four groups; each one contained 3 replicates. Fish was fed with diets containing 0% (control), 0.5%, 1% and 3% concentrations of garlic extract (GE) in diet. 30 days after feeding, survival rate, different biochemical (larvae extract total protein, albumin, globulin, glucose, cholesterol and triglyceride) parameters and digestive enzyme activity (lipase, protease and amylase) were evaluated. There was a significant increase in survival rate of all groups fed with GE as compared to the control diet (P < 0.05). The administration of A. sativum in all levels significantly decreased (P < 0.05) the content of cholesterol, triglyceride and glucose in larvae extract. Also total protein, albumin and globulin levels had significantly increased in all groups fed GE (P < 0.05). The highest total protein (2.13 ± 0.12 g/dL), albumin (0.37 ± 0 g/dL), globulin (1.76 ± 0.12 g/dL), amylase (9.25 ± 0.14 U/mg protein), protease (4.20 ± 0.08 U/mg protein) and lipase (2.62 ± 0.14 U/mg protein) and the lowest serum triglyceride (22.78 ± 0.20 mg/dL), glucose (8.76 ± 0.09 mg/dL), cholesterol (3.69 ± 0.07 mg/dL) levels were observed in fish fed 3% GE in diet. Garlic inclusion in fish diet at 3% concentration is therefore beneficial for use in aquaculture to improve the general health and digestive enzyme activity of M. cephalus larvae.