Effects of dietary protein and energy on growth performance and carcass characteristics of Betong chicken at early growth stage

Nguyen, T.V. and Bunchasak, C. Effects of dietary protein and energy on growth performance and carcass characteristics of Betong chicken at early growth stage Songklanakarin J. Sci. Technol., 2005, 27(6) : 1171-1178 Four hundred and sixteen one-day-old Betong chicks were used to determine the effect of dietary protein and energy levels on growth performance and carcass characteristics. The chicks were randomly allotted into 4x2 factorials in a completely randomized design. Four levels of dietary proteins (23, 21, 19, and 17% CP) and two levels of energy (3,200 and 3,000 ME kcal/ kg) were offered ad libitum to the chicks from 0-42 days of age. There was no significant interaction effect between dietary protein and energy levels in the diets. At 0-21 days of age, the Betong chicks fed with the lowest protein diet (17% CP) showed reduced live weight and weight gain, but not at 22-42 days of age. Dietary protein levels higher than 17% CP did not show any significant effect on growth performance, although increasing dietary protein levels positively improved growth performance and feed utilization. However, the Betong chicks fed with lower protein diet converted protein to body weight gain more efficientcy than those fed higher protein diets (P<0.01). Dietary energy contents of 3,000 and 3,200 ME kcal/kg did not alter the growth performance of the Betong chicks, while higher energy (3,200 ME kcal/kg) increased abdominal fat yield from 0.39% to 0.57% (P<0.05). In contrast, ORIGINAL ARTICLE 1B.Sc.(Animal Science), Department of Animal Science, Faculty of Agriculture, Thai Nguyen University, Thai Nguyen, Vietnam 2Ph.D.(Animal Science), Department of Animal Science, Faculty of Agriculture, Kasetsart University, Chatuchak, Bangkok 10900, Thailand. Corresponding e-mail: [email protected] Received, 12 September 2004 Accepted, 25 February 2005 Songklanakarin J. Sci. Technol. Vol.27 No.6 Nov. Dec. 2005 1172 Growth performance and carcass characteristics of Beton chicken Nguyen, T.V. and Bunchasak, C. dietary protein levels linearly reduced abdominal fat in these animals. In conclusion, protein levels in the diets at 19% CP and energy contents between 3,000-3,200 ME kcal/kg were met or over requirements for growth performance and carcass quality.