IMPACT OF L-CARNITINE SUPPLEMENTATION ON GROWTH OF BROILER CHICKEN THROUGH DETERMINATION OF CHANGES IN THE EXPRESSION OF CAT2, MYOD AND MYF5 GENES

This study explored the impact of supplementation of L- carnitine on the performance of broiler chicken, biochemical parameters and expression of cationic amino acid transporter ( CAT2 ), myogenic determining factor ( MYOD ) and myogenic factor 5 ( MYF5 ) genes. This study included two groups; the first one is the control group and the second one received L-carnitine at a dose 50 mg/kg/day in drinking water. After 35 day, the sera and muscle tissue were obtained for biochemical and real time polymerase chain reaction (qPCR) analysis.  The obtained results revealed a significant increase in the body weight, total body weight gain and a significant decrease in food consumption, food conversion rate in L-carnitine-supplemented group as compared to the control group. Moreover, there was no significant changes in serum cholesterol, triacylglycerol, AST, ALT, total protein and uric acid levels which showed a slight decrease in L-carnitine-supplemented group in comparison with the control group. This study also revealed a significant up regulation for the expression of CAT2 , MYOD and MYF5 genes in muscles of broiler chicken-supplemented with L- carnitine as compared to the control one. The present study concluded that supplementation of L- carnitine to broiler chicken was useful to increase the total body weight gain and muscle mass and this beneficial effect was associated with up regulation of CAT2 , MYOD , and MYF5 genes. Key words : L-carnitine; broiler chicken; growth traits; CAT2; MYOD; MYF5