Comparison of the content of crude protein and amino acids in the whole bodies of cocks and hens of Ross 308 and Cobb 500 hybrids at the end of fattening

Abstract

Dry matter (DM), crude protein (CP), and the content of individual amino acids (AA) were deter - mined in the bodies of Ross 308 and Cobb 500 hybrids including feathers after 40 days of fattening. Percentages for the content of individual AA were then calculated from the total sums of AA. The level of CP, irrespective of sex, was 453.16 ± 5.916 g/kg of DM for the Ross and 470.94 ± 5.404 g/kg of DM for the Cobb hybrid ( P ≤ higher values were found in cocks. Of the total sums of AA in DM of Ross broilers, the largest presence (here and after in %) was that of Glu (14.92), followed by Leu (8.80), Asp (8.73), Gly (8.71), Arg (7.21), Val (6.33), and Pro (6.09). The lowest contents were those of Met (2.41) and His (3.28). For the Cobb hybrid, the AA were Glu (13.90), Asp (9.12), Gly (8.48), Leu (8.43), Arg (7.48), Lys (6.44), and Pro (6.09). The AA lowest contents were those of Met (2.30) and His (3.16).