Threonine requirement of male broiler chicks from 1 to 20, 24 to 38 and 44 to 56 days of age

Revista Brasileira de Zootecnia

Santiago Rostagno, Horacio¹  Vieites, Flávio Medeiros¹  Donzele, Juarez Lopes¹  Oliveira, Jean Eduardo de¹  Albino, Luiz Fernando Teixeira¹  Atencio, Anel¹ 

[1] Universidade Federal de Viçosa

关键词: amino acid;    nutrition;    poultry;    protein    Introdução A treonina é o terceiro aminoácido limitante em dietas para frangos de corte após a metionina + cistina e a lisina;   

DOI  :  10.1590/S1516-35982004000400008

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

Three assays were carried out to determine the threonine requirement and the digestible threonine:lysine ratio of broiler males, Avian Farm, from 1 to 20, 24 to 38 and 44 to 56 days of age. A completely randomized design with five levels of threonine, six replicates and 20 birds per pen from 1 to 20 and 24 to 38, and 16 birds per pens from 44 to 56 were used in each experiment. The concentrations of digestible threonine were 0.684 to 0.870% (in increments of 0.047); 0.637 to 0.807% (in increments of 0.043); and 0.565 to 0.715 (in increments of 0.037) for 1-20, 24-38 and 44-56 days of age, respectively. A quadratic effect due to increasing digestible threonine levels were observed for feed consumption and body weight gain in the 1 to 20 day phase. Using the broken line model, the digestible (total) threonine requirement and the digestible threonine:lysine ratio were 0.777 (0.890 total) and 67%, respectively, according to the results of body weight gain. Not significant response for body weight gain and feed conversion in the second phase (24 to 38 days) showed that the lowest level of threonine met the birds requirement, but the minimum requirement should be lower. Therefore, the digestible (total) threonine requirement and ratio were .637% (.731% total) and 60%, respectively. Leg quarter yield responded linearly with the increase of the threonine level in the second phase (24 to 38). Not significant response for performance, carcass and parts yields in the third phase (44 to 56 days) indicated that the lowest level of threonine met the birds requirement, but new studies should be conducted to determine the minimum requirement. Therefore, the digestible (total) threonine requirement and ratio to maximize the performance were .565 (.650% total) and 60%, respectively.

【 授权许可】

CC BY-NC