Digestible tryptophan requirements for broilers from 22 to 42 days old

Author(s)

Karina Ferreira Duarte ^[1] ; Otto Mack Junqueira ^{[2, 3]} ; Rosemeire da Silva Filardi ^[2] ; Jefferson Costa de Siqueira ^[4] ; Maíra Mangili Puzotti ^[5] ; Edivaldo Antônio Garcia ^[6] ; Andrea de Britto Molino ^[7] ; Antonio Carlos de Laurentiz ^[2]

Affiliation

^[1] Univ Estadual Paulista, Fac Ciencias Agr & Vet, Jaboticabal, SP - Brazil

^[2] Univ Estadual Paulista, Fac Engn, Ilha Solteira, SP - Brazil

^[3] Univ Fed Goias, Jatal, Go - Brazil

^[4] Univ Fed Maranhao, Ctr Ciencias Agr & Ambientais, Chapadinha, MA - Brazil

^[5] Universidade Estadual de Maringá - Brasil

^[6] Universidade Estadual Paulista Júlio de Mesquita Filho. Faculdade de Medicina Veterinária e Zootecnia - Brasil

^[7] Univ Estadual Paulista, Fac Med Vet & Zootecnia, Botucatu, SP - Brazil

• Document type: Journal article
• Source: REVISTA BRASILEIRA DE ZOOTECNIA-BRAZILIAN JOURNAL OF ANIMAL SCIENCE; v. 42, n. 10, p. 728-733, 2013-10-00.

Abstract

The objective of this experiment was to establish different criteria to evaluate the requirements of digestible tryptophan for broilers from 22 to 42 d of age, using different regression models (quadratic, exponential and Linear Response Plateau) and in case of statistical significance the comparison of means by Duncan test at 5% probability was also adopted. A total of 1,920 Cobb 500 male broilers were distributed in a completely randomized experimental design, with 6 treatments (6 digestible tryptophan levels: 0.1395, 0.1610, 0.1825, 0.2040, 0.2255 and 0.2470%) and 8 replications containing 40 broilers each. Performance and carcass characteristics were evaluated. The level of 0.2255% of digestible tryptophan numerically improves feed conversion, and the 0.1919% estimated by the quadratic equation significantly improves carcass yield. (AU)