Evaluation of the tolerance of probiont strains upon intracroup administration to broiler chickens

This paper presents the results of a study of the tolerance of indigenous probiotic strains of the genus Lactobacillus (Loigolactobacillus coryniformis VKM B-3724D and Lactobacillus johnsonii VKM B-3725D), isolated from the gastrointestinal tract of pheasants, to broiler chickens. It was found that the use of the studied indigenous probiotic strains, both individually and in a consortium, had no negative impact on the broiler chickens throughout the entire growing period. The biological drugs were found to not cause any signs of toxic poisoning, while an increase in the survivability and live weight of the experimental birds was observed, as well as a decrease in the feed conversion rate. It was determined that the biological drugs do not negatively affect hematopoiesis or cause inflammation. In fact, they moderately enhance redox processes in the body due to improved saturation of the blood with red blood cells and hemoglobin. A slight improvement in protein, carbohydrate, lipid, and mineral metabolism was observed in serum biochemistry. Based on the combined results of the studies, it was found that the experimental probiotic strains are safe and well tolerated by broiler chickens.