Effects of dietary garlic powder and α-tocopherol supplementation on performance, serum cholesterol levels, and meat quality of chicken

Abstract

This study was carried out to evaluate the effects of supplementing diets with garlic powder and alpha-tocopherol on performance, serum cholesterol levels, and meat quality of chickens. Three hundred 1-d-old male broiler chicks were assigned to 5 diet treatments (0, 1, 3, and 5% garlic powder and 3% garlic powder + 200 IU of alpha-tocopherol/kg) with 3 replications of 20 birds for 35 d. There were no significant differences in broiler performance among the treatments. Moisture and crude ash contents of chicken thigh muscle were not different among all treatments, but dietary garlic powder and alpha-tocopherol supplementation resulted in significantly higher CP and lower crude fat contents in comparison with control (P < 0.05). Increasing the levels of garlic powder and applying garlic powder plus alpha-tocopherol significantly decreased total and low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol in broiler blood (P < 0.05). The pH and TBA reactive substances values were significantly reduced (P < 0.05) by the inclusion of garlic powder and alpha-tocopherol. However, no significant differences in water-holding capacity or shear force values were observed among the treatments. For broiler thigh muscle color, L* (lightness) values were decreased (P < 0.05), and a* (redness) and b* (yellowness) values were increased (P < 0.05) with the increased garlic powder levels and the combination of garlic powder and alpha-tocopherol. In terms of fatty acid composition in thigh muscle, unlike saturated fatty acid and total saturated fatty acid, dietary garlic powder or garlic powder plus alpha-tocopherol supplementation increased unsaturated fatty acid, total unsaturated fatty acid, and total unsaturated fatty acid:total saturated fatty acid ratios. These results suggest that 5% garlic powder or 3% garlic powder plus 200 IU of alpha-tocopherol antioxidant properties were effective for enhancing lipid and color stability.