EN
The experimeit was carried out on 1350 Astra В chickens divided into 5 groups. Standard mixture was fed to the control group. In the remaining four groups, the amount of maize meal was decreased and half of the soybean meal replaced by 15/13% of rapeseed meal. The kind and the amount of antibiotic added to the mixtures varied. The mixtures contained 8/6 mg or 12/6 mg of flavomycin per kg or 10/10 mg or 20/10 mg of tylosln per kg. The final body weight in the control group as well as in the groups fed on mixtures supplemented with rapeseed meal and 8/6 mg of flavomycin, was about 4% higher compared with that in other groups. Feed consumption was the lowest in the controls /P< 0,01/. Productivity effects were better in the groups receiving 8/6 mg of flavomycin per kg of the mixture compared to those fed on •mixtures supplemented with tylosin. Rapeseed meal supplement in the mixtures resulted in the increase of thyroid weight by 22-37%.