Different criteria for feed formulation based on digestible amino acids for broilers

Abstract

An experiment was carried out to evaluate different criteria in feed formulation based on digestible amino acids for broilers during the grower phase. Diets were formulated according to the recommendations for digestible methionine, methionine + cysteine, lysine, and threonine. A total number of six hundred Cobb 500 male day-old chicks were distributed in a completely randomized experimental design, with three formulation criteria supplying the recommendations established by Baker & Chung (1992), Degussa (1997), and Rostagno et al. (2000), with 4 replicates of 50 birds each. No significant differences were observed for weight gain and feed intake. However, feed conversion ratio improved when birds were fed the diets containing the profiles recommended by Baker & Chung (1992) and Degussa (1997). No difference was observed in terms of leg, wings, back, and head yields. Broilers fed with the profile of Baker & Chung (1992) presented worst breast yield, whereas those fed the Degussa (1997) standard had better carcass yield

Fontes de metionina em rações formuladas com base em aminoácidos totais ou digestíveis para frangas de reposição leves e semipesadas

“…De acordo com Emmert & Baker (1997), mesmo em rações à base de milho e farelo de soja, é conveniente considerar a composição em aminoácidos digestíveis, sobretudo quando utilizados aminoácidos sintéticos, que são 100% digestíveis, enquanto a digestibilidade média dos aminoácidos provenientes do milho e do farelo de soja é de aproximadamente 89%. A efetividade da formulação de rações pelo conceito de aminoácidos digestíveis foi comprovada para frangos de corte (Rostagno et al, 1995;Wang & Parsons, 1998;Douglas & Parsons, 1999;Araújo et al, 2006;Gomes et al, 2004;Maiorka et al, 2004), no entanto, para poedeiras comerciais em fase de postura, os resultados ainda são controversos (Silva et al, 2000;Casartelli et al, 2004). Para as fases inicial e de crescimento, não foram encontrados relatos científicos.…”