Growth and Carcass Composition Response of Different

The purpose of this experiment was to assess the impact of various protein levels and of the administration periods of concentrate mixture (CM) on the growth and carcass composition in Ross 308 hybrid ecologically raised. The experiment was conducted over a period of 84 days on a flock of 108 chickens belonging to Ross 308 commercial hybrid. There were three experimental groups consisting of 36 chickens. The chickens were fed with the tri-phase feeding program in G1, and with the bi-phase feeding program in G2 and G3, as follows: G1 and G2 with the same period of administration of CM and with close protein levels, but in G2 the biological value of the protein in CM starter was higher. G3 chickens were fed with the bi-phase feeding program, respectively 1-28 days and 29-84 days where the protein level was of 20.94 % and 16.98 % CP. Chickens in G2 and G3 received the same CM starter structure with a protein level of 20.94 % with an upper VB. Statistical analysis of the received results was performed by the IBM SPSS 19 software using the analysis of the variant and the testing of significance with ANOVA test complemented by Tukey posthoc test. It can be appreciated that the body weight was significantly influenced (G2-3826.33 g, and in G3-3669.96 g) by incorporating an animal protein source (boiled egg) in the CM structure, which after a good start allows the application of a two-phase feeding technology (in G3), which significantly simplifies the growing process of broilers. This experimental scheme did not cause significant differences in the quality of meat or in the weight of the cut-up parts of the broiler carcasses