The authors of this article evaluated the effectiveness of the use of a feed additive based on soy protein hydrolysate of the enzymatic cleavage method in combination with iodine and selenium in broiler chickens in the framework of studying its pharmacological properties. The indicators of livestock safety in the experimental group by the end of the experiment were 100.0 %, and in the control group − 84.0 %. In the experimental group, the increase in live body weight was 13.9 % higher compared to the group that did not receive a feed supplement. According to the calculations, the cost of compound feed per 1 kg of weight gain of poultry during the growing period in the ex-perimental group was 1.8 kg, which was 14.2 % lower compared to the control group. The slaughter yield of carcasses in the experimental group was 66.7 %, while in the control group − 62.0%. During the veterinary and sanitary examination, it was determined that the meat of the experimental and control group of broiler chickens was obtained from a healthy bird and was of good quality and suitable for further processing.