Survey on antimicrobialresidues in raw milk andantimicrobial use in dairyfarms in the Emilia-Romagnaregion, Italy

摘要

This survey investigated the antimicrobialsmost commonly used in dairy herds andantimicrobial residues most frequently detected in milk to evaluate the suitability of rapidscreening tests to determine antimicrobialresidues in milk. The investigation was carriedout in 45 dairy herds consulting the farmadministration records and in a national dairyindustry collecting milk from almost all thedairy farms studied. Data were recorded on: i)treatments with drugs containing antimicrobials during the 12 months prior to the visit; ii)antimicrobial active substances present in thedrugs; iii) data from routine controls to detectantimicrobial residues (52,771 samples). Theantimicrobial classes most commonly usedwere penicillins, cephalosporins, fluoroquinolones, macrolides, sulphonamides, tetracyclines, aminoglycosides and lyncosamides;the most frequently used antimicrobial notbelonging to any of the previous groups wasriphaximin. Sixty-four samples collected frommilk trucks yielded antimicrobial residuesexceeding the detection limit of the screeningtest used: sulphonamide residues were themost prevalent (3.4%), followed by tetracycline(0.3%) and penicillins and cephalosporins(0.03%). The antimicrobial classes most commonly used on dairy farms are the same as theresidues most frequently detected in milk. Theassociation of several commercially availablerapid test kits proved satisfactory for determination of the veterinary antimicrobial drugsmost used on dairy farms but at least five kitsare required. Therefore, knowledge of the most frequentlyused veterinary drugs and periodic monitoringare required for the dairy industry to develop atargeted and effective control plan.