Author(s): MAA Metwally
Th is study was carried out to show the effects garlic ( Allium sativum ) on antioxidant system i n Tilap ia nilotica ( Oreochromis niloticus ). A total number of 120 fish (20-21g in weight) was used. Fish wer e divide d into four groups fed on diets containing garlic in different forms; natural garlic (40g/kg diet), garlic oil capsules (Strongus®, pure garlic oil capsules; 250 mg/kg diet) and garlic powder tablets (32 g/kg diet), wit h three replicates for each treatment. Treatment groups had a different sources of garlic added to their diets; th e control group diet was free from garlic. The experiment extended for three months. The results showed that , weight gain and growth performance of O. niloticus significantly (P<0.01) increased in all groups fed on garlic with lower mortality rate than the control group. Glutathione peoxidase (Gper), superoxide dismutase (SOD) , cata lase (CAT) increased significantly (P<0.01) as compared to the control group. Malonyldialdehyde (MDA). Al kaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activitie s in plasma d ecreased significantly(P<0.01) in all treated groups of garlic. Total protein in blood seru m signifi cantly increased (P<0.01) in the groups fed on garlic, while blood glucose, triglycerides and cholestero l levels were significa ntly decreased (P<0.01) in the same treated groups. In conclusion, it can be suggested that, addi tion of garlic in any form to fish diet can promote growth rate, decrease mortality rate and increase th e antioxidant activity in fish.