INVESTIGATIONS OF FEEDING COMPOUND FEEDS WITH DIFFERENT CORN MEAL LEVELS ON PRODUCTIVE AND SLAUGHTER TRAITS IN BROILER CHICKENS | Проучване ефекта от храненето с комбинирани фуражи с различно участие на царевичен шрот върху продуктивните и кланични показатели на пилета бройлери

A 42-day experiment was carried out to evaluate the effect of feeding compound feed with different content of corn meal on productive and slaughter traits of Ross 308 hybrid broiler chickens. For this purpose, 120 one-day old male chickens reared in batteries, divided in 4 equal groups - one control and three experimental with 3 repetitions per group. All chickens received balanced isocaloric and isoprotein rations. The main protein source in controls was soybean meal, and experimental groups I, II and III were fed a different amount of corn meal - 15, 20 and 25 %, respectively. The inclusion of 20 and 25% corn meal in compound feeds up to 28 days of age reduced statistically significantly the live body weight of chickens compared to controls. BY the age of 42 days, chickens from group I (15% corn meal) and II - 20% corn meal succeeded to compensate for the stunted growth vs controls - 2562 g attaining live body weights of 2468 g and 2423 g respectively - Р0.05, whereas those of group III which received a diet with highest corn meal share - 25% exhibited a significantly lower body weight by 12.4%. Over the 42-day finishing period, controls and chickens fed 15% corn meal were with equal feed conversion 1.682 and 1.699 kg feed/kg weight gain, whereas groups that received rations with 20 and 25% corn meal, were with higher feed conversion – by 4.4 and 8.0% respectively, vs controls. The inclusion of 15, 20 and 25% corn meal in poultry feeds reduced the grill weight - Р0.05 as compared to control group. Only the group receiving a feed with the highest corn meal proportion - 25% showed a lower breast weight - Р0.05, whereas leg weights were considerably lower in groups fed compound feeds containing 20 and 25% corn meal. There were no significant differences among groups with regard to chemical composition of meat - water, protein and fat contents.