Influence of β-Adrenergic Agonist (Metaproterenol) and Lysine on Growth, Carcass Quality in Broiler Chickens

Abstract

An investigation was made to find out the importance of $ adnergenic and lysine on carcass characteristics and blood metabolite of 648 broiler chickens from 2142 days of age. Effect of metaproterenol (a $2adrenergic agonist) and lysine were assessed by mixing them in feed at 0.0, 0.25, 0.50 and 1.00 ppm metaproterenol sulfate and 100%, 115% and 130% of NRC recommended lysine in a 4×3 factorial arrangement of treatments. Chickens were reared under normal condition to 3 week of ages and then randomly allocated to treatments. Each treatment contained 3 pens with 18 birds/pen. Body weight gains (BWG), feed conversion ratio (FCR) abdominal fat pat (AFP) breast weight (BW) were measured. Result indicate that during 4 and 5 week of study using metaproterenol (0.5 ppm ), compare to control group, th th improved BWG (5.1%), carcass efficiency (3.4%) and breast weight (2.2%), breast and thigh muscle protein and depressed abdominal fat (P<0.05). Increasing lysine levels lead to significant increase in body weight gain, carcass weight, carcass efficiency, breast muscle weight (P<0.5), but it has no effect on feed intake, feed conversion ratio, blood metabolites. Data from this experiment suggested that both adding 0.5 ppm $adrenergic agonist metaproterenol sulphate significantly improved birds performance and their carcass quality and the most efficient lysine level for broiler chickens was proved to be 115% NRC recommended.