A review on the effect of L-carnitine supplementation in diets of broiler chickens

Abstract

L-carnitine is a nutritional supplement having fat-burning property and plays important role in lipid metabolism, energy release, and also improve the production yield, immunity and blood constitutes. This paper reviews the effects of L-carnitine on quantitative and qualitative characteristics of broilers. According to the reviewed literatures, the application of L-carnitine(50-200 mg/kg) have not significant effect on the growth performance; however, using L-carnitine as much as 300-800 mg/kg resulted to an improvement in the body weight (2226-2575g) compared to the control chicks (1998.40-2338.75g). The feed conversion ratios of the chickens fed same amount of L-carnitine were 1.66-1.86g/g, which was improved in comparison with the control chicks (1.87-2.09). Abdominal fat of the broiler chickens fed 50-900 mg/kg L-carnitine were 0.98-1.75%, which is lower than the control chicks (1.79-2.16%). For immunity, the antibody titers against the Newcastle virus in the chickens fed 250 mg/kg L-carnitine were between 4.6- 5.5 which is more than control chicks (4.3-5.2). The antibody titer against the influenza virus in the chickens fed same amount of L-carnitine was between 5.6-6.3, which was more than the control chicks (4.3-5.8). The use of 100-600 mg/kg L-carnitine could reduce triglyceride (90-104.4 mgdL -1 ) compared to the control chicks (125-104.7 mg dL -1 ) and also reduced the cholesterol (109-115 mg dL-1) compared to the control chicks (129.25 to 131 mg dL -1 ). The application of 100-600 mg/kg L-carnitine also could reduce LDL from 19.1-72.2 mg dL -1 to 16.5-49.0 mg dL -1 . However, the application of 100-900 mg/kg L-carnitine had not significant effect on the sensory characteristics of broiler chicken meat. In general, it can be concluded that L-carnitine can use as a dietary supplement affective on the health of broiler chickens without any negative effect on growth performance.