Abstract
The feeding value of high-oil corn fed to Taiwan Country (TC) chicken was examined by measuring apparent metabolizable energy (AME), growth performance, sexual maturity, carcass characteristics, and plasma pigmentation. In a completely randomized design, 870 sex-intermingled one-wk-old chicks were assigned to one of 30 floor pens, 29 birds per pen, and each pen randomly assigned to one of five dietary treatments. The experiment was ended when birds were 16 wk of age. The five dietary treatments varied in main fat sources, which were corn oil (CO), high-oil corn (HOC), lard (LRD), whole soybean (WSB) and yellow corn (YC), respectively. All the diets were formulated isonitrogenously, isocalorically, and of equal lysine and methionine contents except YC, in which equal amounts of YC replaced HOC. The results indicated that feed conversion in HOC was 8% higher (p<0.05) than YC whereas the calculated AME of HOC was only 3.5% to 4.0% higher than that of YC. No significant differences were observed in body weight, body weight gain, feed consumption, feed conversion ratio and ME efficiency for body weight gain among CO, HOC, LRD, and WSB. No significant differences existed in both skin and muscle pigmentation of breast among the five dietary treatments. No significance differences existed in plasma carotenoid content measured at various ages among the five dietary treatments except that birds fed with HOC had less (p<0.05) plasma carotenoids at 16 wk-old. The results indicate that if the price of high-oil corn is no more than 1.05 times that of yellow corn, the dietary cost per kg of body weight gain for TC chickens fed diets containing high-oil corn will be less, although their body weight may be lighter compared to chickens fed diets formulated with other fat sources.