Vol. 45, No. 4, 2001
THE EXCRETION OF TYLOSIN RESIDUES IN EWES' MILK AFTER ITS EXPERIMENTAL ADMINISTRATION
Nagy, J., Popelka, P., Sokol, J., Turek, P., Neuschl, J.
University of Veterinary Medicine
Komenského 73
041 81 Košice
The Slovak Republic
Summary
Seven clinically healthy ewes (Slovak merino) were used in the experiment. The ewes were treated intramuscularly with tylosin base 0.05 g.ml-1 (Ivatyl 50 inj. ad us. vet. Bioveta, The Czech Republic) at a dosage of 100 mg.10 kg-1 for five consecutive days. The milk samples were collected before treatment, and at 12-h intervals for 7 days during and after the treatment. The samples were analysed by a high-performance liquid chromatography method with solid phase extraction.
The mean values of tylosin residues in the milk were 631.6 mg.l-1 12 hours after the first administration. The highest mean concentrations were detected 12 hours after the second injection (1821.6 mg.l-1). After the end of the drug administration, the residue concentrations decreased, and 36 hours after the last administration the tylosin residues were found below the maximum residual limit (50 mg.kg-1) and the mean concentration was 30.9 mg.l-1. The residues were not detected in the ewes' milk 48 hours after the completion of the drug administration.
Key words: residues; tylosin; ewes' milk
References
Folia Veterinaria / 2001