Digestible isoleucine requirements for 22- and 42-day-old broilers

Karina  Ferreira Duarte; Otto Mack  Junqueira; Rosemeire  da Silva Filardi; Antonio Carlos  de Laurentiz; Carla Heloísa  de Faria Domingues; Eliana Aparecida  Rodrigues

Digestible isoleucine requirements for 22- and 42-day-old broilers

Autores

Karina Ferreira Duarte

Otto Mack Junqueira

Rosemeire da Silva Filardi

Antonio Carlos de Laurentiz

Carla Heloísa de Faria Domingues

Eliana Aparecida Rodrigues

Editor

Universidade Estadual de Maringá

Descripción

Current experiment established different criteria to evaluate the requirements of digestible isoleucine for 22- and 42-day-old broilers by different regression models (quadratic, exponential and Linear Response Plateau) and, in the case of statistical significance, the comparison of means by Duncan’s test at 5% probability. A total of 1,920 Cobb 500 male broilers were used in an entirely randomized experimental design, with 6 treatments (6 digestible isoleucine levels: 0.6118; 0.6655; 0.7192; 0.7729; 0.8265 and 0.8802%) and 8 replications, with 40 broilers each. Data on performance and carcass characteristics were evaluated. Level 0.7192% of digestible isoleucine was considered standard. The digestible isoleucine level recommended for 22- and 42-day-old broilers is 0.7729%, corresponding to a digestible isoleucine:lysine ratio of 72%.