Growth performance and carcass composition of broilers fed supplemental chromium from chromium yeast

Three experiments were conducted to evaluate the effects of chromium (Cr) from Cr yeast (1 g kg(-1)) on the growth and carcass composition of growing broilers. The birds were fed corn soybean meal diets containing a basal level of 650-710 mu g kg(-1) Cr. The diet was supplemented with Cr at a level of 0, 300, 600 mu g kg(-1) (Trial 1); 0 and 400 mu g kg(-1) (Trial 2) and 0, 150 and 300 mu g kg(-1) (Trial 3). Supplementation with Cr did not affect (P greater than or equal to 0.05) body weight, feed consumption or feed:gain ratio of broilers during days 1-21 in trial 1 which was conducted in battery brooders. Male broilers reared in floor pens (Trial 3) during days 1-21 had significantly (P less than or equal to 0.01) higher feed consumption with 300 mu g kg(-1) Cr in the diet, but the feed:gain ratio between the treatments was unaffected. Body weight of mixed sex broilers from days 28-47 was not influenced, but feed:gain ratio and mortality were significantly (P less than or equal to 0.05) reduced with 400 mu g kg(-1) of Cr in the diet in Trial 2. Broilers reared in floor pens with supplemental Cr at a level of 300 mu g kg(-1) had significantly (P less than or equal to 0.05) higher body weight at 42 days in Trial 3. Feed consumption was significantly increased and feed:gain ratio was improved (P less than or equal to 0.05) with 300 mu g kg(-1) of supplementary Cr in the diet. Mortality of broilers was reduced, and breast meat yield improved (P less than or equal to 0.05) with supplemental Cr at either 300 or 400 mu g kg(-1). Carcass weight was increased and abdominal fat pad as a percent of carcass weight was reduced significantly(P less than or equal to 0.05) with 300 mu g kg(-1) supplemental Cr in the diet. (C) 1998 Elsevier Science B.V.