Print version ISSN 0103-8478
MENDOZA, Maria Olinda Bergamo et al. PERFORMANCE OF SEXED BROILER BIRDS, SUBMITTED TO DIETS FORMULATED BY THE CONCEPTS OF CRUDE PROTEIN versus IDEAL PROTEIN. Cienc. Rural [online]. 2001, vol.31, n.1, pp. 111-115. ISSN 0103-8478. http://dx.doi.org/10.1590/S0103-84782001000100018.
The study was carried out at the Poultry Section of the Departament of Animal Science at Federal University of Santa Maria, in order to evaluate the performance of broilers grown sexed and fed with diets formulated by the traditional concept (Crude Protein - CP), which is based on total amimo acids (TAA) and fed with the approach of Ideal Protein (IP), which is based on digestible amino acids (DAA), in the period from 1 to 42 days of age. A comparative economic analysis among the two feeding methods was also accomplished. There were 960 chicks (Ross) at the age of 1 day, being 480 males and 480 females. The diet based on the concept of CP was formulated according to the recommendation of NRC (1994) and the diet formulated by the concept of IP was adapted from Han and Baker (1994). The completely randomized experimental design consisted of 4 treatments with 12 replications of 20 chicks each. The feed intake, phase gain, body weight, daily gain, feed conversion and the nutritional efficieny index were evaluated. The results indicated that the parameters studied were more efficient in the initial phase. The diet formulated by the Ideal Protein concept, based on the content of DAA, influenced all parameters studied positively, providing significantly better gain weight and feed efficiency in both male and female chicks in the initial and final phases, being similar in the growing phase. The chicks fed with DAA showed greater profits in the initial phase and during the growth phase. These data allowed the conclusion that diets containing corn and soybean meal as base for the formulated feed provides better biological and economic performance of the broilers when compared to those formulated with crude Protein, from day the first up to 35 days of age. The final phase (35-42) showed the contrary, being the CP concept more economical than IP.
Keywords : broilers; performance; crude protein; ideal protein.