Cyclophosphamide content in the meat and milk after a single application to sheep

Investigated were two groups of 10 Merino sheep each. The test group were given orally cyclophosphamide, singly, at the rate of 25 mg/kg, while the controls of the second group were not treated but were kept under the same conditions. Both milk and meat of the two groups were investigated by thin layer chromatography and gas chromatography on the 1st, 4th, 9th, 14th, 23rd, and 30th day following the introduction of cyclophosphamide. The results obtained by gas chromatography showed that it was not until the fourth day that there were two metabolites of the compound in milk only. On the 9th day the same were established in the milk and meat samples in a maximum concentration, the excretion from the body of the treated animals starting as early as the 14th day. By the 23rd day there were traces only, and after the 30th they were no longer established. Thin-layer chromatography showed that the two metabolites were found in approximately equal amounts up to the 14th day following treatment, and were fully excreted after the third week. Therefore, the full elimination of cyclophosphamide metabolites from the milk and meat of sheep treated with it at the rate cited takes place in about four weeks.