[Penicillin residues in yearlings following preventive treatment of summer mastitis with a preparation containing high doses of penicillin for use of dry cows (author's transl)].

In view of questions arising in the field, regarding the periode for which treatment with a preparation containing high doses of penicillin for use of dry cows to prevent summer mastitis may result in a positive kidney test, the urinary concentrations of penicillin in these animals were determined. The study of these levels, in conjunction with previous experience in cattle, showed that kidney tests are only likely to be positive during the first two days.