Abstract
This study was performed to investigate the effects of dietary supplementation with garlic and turmeric powder as growth promoter agents on performance, carcass traits, serum biochemistry, and antioxidant enzyme activities of growing rabbits. A total of 112 New Zealand White rabbits (NZW) at 5 weeks of age were randomly assigned to seven treatments with four replicates. The dietary treatments consisted of 7 groups as follows; the basal diet as control, phytogenic additives groups were supplemented with 2, 4, and 6 g/kg garlic or turmeric powder added to the basal diet. There were no linear and quadratic differences (P<0.05) in growth performance after garlic or turmeric supplementation at all studied ages. Compared with the control group, supplementation of diets with garlic or turmeric linearly and quadratically elevated immunity biomarkers such as total protein (TP), albumin (AL) and immunoglobulin (IgG) levels and decreased (linearly and quadratically, P<0.05) aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG) and total cholesterol (TC) levels in rabbit serum. However, TP, AL, globulin (GL), IgG and IgM levels were linearly and quadratically enhanced with increasing turmeric levels versus the control diet. Hepatic superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase GSH-Px activities as well as reduced glutathione (GSH) concentrations were linearly and quadratically (P<0.05) improved in garlic or turmeric additives fed groups. While MDA concentration was statistically (linearly, P=0.022) reduced in comparison with the control group. It could be concluded that garlic or turmeric supplementation (2, 4 and 6 g/kg) did not linearly and quadratically affect growth performance but improved the immunity responses and lowered the lipid profile in blood and lipid peroxidation in liver and increased hepatic antioxidant activity in treated rabbits.