Studied were some of the aspects of the antibiotic treatment with flavophospholipol (moenomycin) as the preparation flavomycin, and virginiamycin (staphylomycin) as the preparation escalin in a premix form as an animal formula. It was found that the antibiotics tested acted as nutrients: they had a positive effect on the growth and feed conversion. They raised the production of meat and improved the quality of the meat product in terms of higher protein and mineral contents. They also influenced favorably the deposition of cyanocobalamin in the liver, the RNA: DNA ratio in the liver and pancreas, and the content of blood proteins. These antibiotics did not lead to the retention of residual amounts in the muscles and viscera. Both preparations proved useful for the practice. Flavophospholipol is of interest thanks to its easier dosing and positive effect on the cyanocobalamin and ubichinon deposition in the liver and partly as its stimulative action.