[Chemical composition of the meat of chickens treated with antibiotics].

Studies were carried out on the chemical composition of meat obtained from a total of 150 Leghorn birds at the age of four weeks, treated with nine antibiotic preparations. When the antibiotics were applied at therapeutic rates certain changes took place in the amount of total nitrogen as well as in the amino acids tryptophane and hydroxi-proline, which depended on the type of the antibiotic used. The study of muscle samples from the test groups revealed negligible rise (P greater than 0.05) of the fats and water to the detriment of total nitrogen as against the values of the same indices of the controls. Demonstrated was the higher biologic value of white meat proteins as shown by the control group as compared with the test groups. The withdrawal time was found to be six days during which full elimination of the antibiotic preparations from the body of the birds was achieved, and there was no rise both of the total nitrogen and of the index of the tryptophane/hydroxi-proline ratio.