Effect of low protein diets adequate in levels of essential amino acids on broiler chicken performance
2000
Hai, D.T. (Hanoi Univ. of Agriculture (Viet Nam). Faculty of Veterinary and Animal Science) | Blaha, J.
An experiment was conducted to study effects of isoenergetic low-protein diets supplemented with Met, Lys, Thr and Trp on broiler chicken performance. The chicks of both sexes were divided into 4 groups, corresponding to 21.66/18.79/17.5 %; 20.04/18.79/17.5 %; 20.04/17.69/17.5 % and 20.04/16.52/17.5 % CP diet. Each group had three diets corresponding to three fattening periods of 1-21 d, 21-35 d and 35-40 d. Besides the CP content, all of the diets were formulated in order to satisfy the need of essential amino acids. No significant difference in the weight gain of both sexes from 1-21 days of age was observed between the 21.66 % and 20.04 % CP diet (P0.01). From 1-40 days of age, the male chicks fed the 20.04/16.52/17.5 CP diet had significantly lower weight gains in comparison to the control. The growth rate of females receiving low-protein diets from 1-40 days of age was not significantly different from the control (P0.01). The feed conversion was worsened by lowering dietary CP levels, but the feed costs per kg of weight gain were reduced. The decrease in dietary CP level had no negative effects on dressing percentage, muscle proportion in live weight and carcass protein. However, low-protein diets resulted in a higher abdominal fat deposition.
显示更多 [+] 显示较少 [-]