Abstract. In the conditions of the research and production laboratory of the ERC “Agrotechnopark” of the Belgorod State Agrarian University, a scientific and economic experiment was carried out to study the effect of feed additives acidifier “AsidLak” and “ButiPERL” calcium butyrate on slaughter indicators, morphology of broiler carcasses, chemical composition of pectoral and leg muscles, organoleptics of meat and broth. Methods. Chickens of the 1st experimental group were introduced into the main diet of the acidifier “AsidLak” in the amount of 5 kg/t, the 2nd experimental group was injected with 0.3 kg/t of calcium butyrate “ButiPERL”, the 3rd experimental group – a complex of feed additives in dosages 1 and 2 of the experimental groups without the introduction of antimicrobial drugs; broiler chickens of the control group received a complete mixed feed (OP). When growing chickens, a three-phase feeding system was used. During the experimental period, broiler chickens were grown outdoors, under the same conditions. According to the results of the study, it was found that broilers of the 3rd experimental group had the highest pre-slaughter live weight in comparison with the control by 104.67 g or 4.0% (P ≥ 0.95), which is also higher than analogues 1 and 2 experimental by 14 g (0.51%) and 48 g (1.76 %); broilers of the 3rd experimental group had a greater mass of gutted carcass – 1870.73 g, which is higher compared to the control group by 132.96 (7.65 %), and also 1 and 2 experimental by 43.93 g (2.35 %) and 77.96 g (4.17 %). 68.7 %. An increase in the content of dry matter, fat and protein in the pectoral and leg muscles, as well as an improvement in the taste and biological value of meat was noted. The scientific novelty lies in the fact that for the first time on the livestock of the Ross-308 cross, an acidifier and butyrate were used in combination as an alternative to antimicrobial drugs.