Carcass and organ characteristics of broilers fed graded levels of processed castor oil bean (<i>Ricinus communis L</i>) meal and supplementary L-lysine

Abstract

The effect of graded levels of heat-treated castor oil bean meal and supplementary L-lysine on carcass and organ characteristics of broiler birds was investigated. In experiment 1, 180 seven-day old broiler chicks (Anak strain) were randomly divided into 12 groups of 15 birds each. In experiment 2, 144 six weeks old broiler finishers were randomly divided into 12 groups of 12 birds each in a 4 x 3 factorial arrangement involving four processed castor oil bean meal levels (0, 10, 15 and 20%) and three L-lysine levels (0, 0.25 and 0.5%). At the 6th and 10th weeks of experiments 1 and 2, respectively, 3 birds per treatment were randomly selected and weighed for carcass and organ evaluation. Results showed that live body weight and weights of liver, kidney, spleen and heart decreased significantly (p<0.05) at the 15 and 20% CBM inclusion levels, while the empty gizzard weight was decreased (p<0.05) at the 20% CBM inclusion level (experiment 1). In experiment 2, live body weight, dressed carcass weight, dressing percentage and weights of liver, kidney, spleen, heart, empty gizzard and relative heart weight declined (p<0.05) at the 20% CBM inclusion level. The abdominal fat weight, relative weights of liver, kidney heart, empty gizzard and abdominal fat were significantly (p<0.05) increased. There were significant (p<0.05) CBM x Llysine
interactions on body weight, liver weight, relative liver weight, kidney weight, relative kidney weight, spleen weight, relative heart weight, empty gizzard weight and relative empty gizzard weight. Supplementation of some diets with L-lysine significantly (p<0.05) increased body weight
of birds at all levels of CBM inclusion and increased (p<0.05) dressed carcass weight at the 15 and 20% CBM levels. Results show that up to 10 and 15% processed CBM can be included in broiler starter and finisher diets, respectively without adverse effects on carcass and organ weights of
broiler birds.

Keywords: Castor oil bean meal, L-lysine, carcass, organ weights, broiler chicks