Growth Response, Carcass Yield and Serum Biochemistry of Broiler Chickens Fed with Supplemental L-carnitine in Feed or Drinking Water

Abstract

The effect of varying inclusion levels of L-carnitine and mode of application (in diet or drinking water) on growth response, carcass yield and serum biochemistry of broiler chickens was investigated. Seven experimental diets were for-mulated in a 2×3+1 factorial arrangement. The dietary treatment consisted of two factors representing modes of application (either in feed and water application) at three levels (40, 50 and 60 mg per kg of diet or liter of drinking water) plus control diet (which had no L-carnitine either in feed or drinking water). Three hundred and fifty day old (350), unsexed broiler chicks were randomly allocated into 7 dietary treatment groups replicated five times with 10 birds per replicate. Final live weight (P<0.01) and weight gain (P<0.001) of the birds increased with increasing supplemental levels of L-carnitine. Broiler chickens supplemented with 60 mg L-carnitine (either in feed or drinking water) recorded the highest (P<0.05) weight gain, feed intake and least (P<0.05) serum triglyceride and feed conversion ratio (FCR). Birds offered supplemental L-carnitine in feed had higher (P<0.05) feed intake and improved feed conversion ratio than those offered L-carnitine in drinking water. Irrespective of the mode of application, broilers offered 60 mg supplemental L-carnitine showed best FCR. Dressed weight, dressing percentage, breast meat yield and back weight increased (P<0.05) while abdominal fat reduced (P<0.05) with increasing inclusion levels of L-carnitine. Broilers fed with diets supplemented with 60 mg/kg L-carnitine had the highest (P<0.05) dressed weight, dressing percentage, breast weight, back weight and the least (P<0.05) abdominal fat weight. Supplementation of L-carnitine in feed showed better growth response than oral application. Dietary supplementation of 60 mg/kg L-carnitine in broiler feed resulted in improved growth response and carcass yield without an adverse effect on the serum biochemistry.