Fattening Performance of Bulls of three Breeds Fattened Semi-Intensively in the Kostanay Region

The aim of this study was to determine the effect of cattle breed on carcass traits and meat quality of bulls fattened semi-intensively and slaughtered at 18 months of age. The animals were divided into three experimental groups: Group AA - 16 Angus bulls, group WK - 19 Kazakh White headed bulls, group AK - 20 Kazakh Aulie-Ata bulls. All bulls were slaughtered at the end of the fattening period. Angus bulls had the highest (p≤0.05) final body weight (494.9 kg) at 18 months of age. Average daily gain was also highest (p≤0.01 and p≤0.05) in group AA (863 g). Angus bulls were characterized by the highest carcass dressing percentage (56.8%) and the highest fat content (3.4%). Carcass length and thigh circumference were significantly (p≤0.05) higher in AA bulls than in AK bulls. The content of lean meat and fat in the carcass was highest (79.4%, p≤0.05) in AA bulls and lowest in AK bulls. Samples of semitendinosus muscle collected from AA bulls had the highest content of dry matter (24.89%), protein (22.5%) and fat (2.27%, p≤0.05).