[Subchronic toxicity of apramycin in pigs].

Use was made of four groups of six pigs each, weighing 40 to 50 kg to follow up the toxicity of Pharmachim's apramycin in the form of water-soluble powder of apramycin sulfate, given at the rate of (nil), 300, 500, and 1,000 mg per liter of drinking water in the course of 35 days. It was found that such treatment did not lead to changes in the general status of the animals. On the contrary, apramycin sulfate stimulated growth and improved feed conversion. In concentrations of up to 300 mg/l the preparation did not produce an essential effect on the clinico-laboratory indices, and did not lead to toxic alterations of the viscera. In concentrations of 500 and 1,000 mg/l and extending the period to more than 15 days an occasional drop of the percent of lobular neutrophilic leukocytes and rise of the percent of lymphocytes in the blood might occur. This could lead to dystrophic processes in the liver and to negligible changes of the same character in both the kidneys and the heart.