Growth Performance and Carcass Characteristics of Broilers Fed Different Levels of Dietary Lysine

Abstract

The effect of feeding different levels of dietary lysine (100%, 110% and 120% of NRC 1994 recommendations) was

evaluated in the current study. These levels were included in broiler starter and finisher diets. A completely

randomized experimental design was used. Feed intake and body weight gain in broilers receiving 110% of NRC

1994 lysine, were significantly (P≤0.05) increased versus control. However, feeding 120% lysine significantly

(P≤0.05) decreased feed intake. Body weight gain was not different (P≥0.05) among broilers fed control diet and

120% lysine. Feed conversion ratio was not significantly (P≥0.05) different among dietary lysine levels. There was no

significant (P≥0.05) effect of dietary lysine levels on dressing percentage, relative weight of gizzard and liver.

However, relative weight of abdominal fat decreased significantly in broilers received 110% and 120% of NRC

lysine. It was concluded that offering 110% of NRC lysine to broiler chicks enhanced feed intake and body weight

gain, but supplying of dietary lysine to broiler chicks above this level might decrease feed intake. Addition of 110%

and 120% NRC lysine to broiler diet declines relative weight of abdominal fat.