STUDY REGARDING SEASONAL INCIDENCE OF FLUOROQUINOLONS IN COW RAW MILK AND THEIR RELATIONSHIP WITH SOMATIC CELLS COUNT

The aim of this study was to investigate the incidence of fluoroquinolone residues in raw cow milk and to evaluate the relationship between these residues and somatic cell count (SCC) value during summer and winter season. The study was carried out in the period May 2016 - June 2017, on 360 milk samples obtained from three dairy farms from north-western Romania. The milk samples were analysed by LC-MS/MS method. Out of all samples, 243 samples (67.50%) were positive for fluoroquinolone residues. The examined samples presented values below the recommended maximum residue limit (MRL). Enrofloxacin and its indicator residue, i.e. ciprofloxacin were the most frequently determined. The results of the study indicate that incidence of fluoroquinolone residues in winter season was higher than in summer. Also, SCC value was higher for milk samples with positive antibiotic residue. Our investigations denote that fluoroquinolones are frequently administered to the dairy cows despite of the EU and national recommendations.