ANTIMICROBIAL USE ON DAIRY FARMS IN ALBERTA, CANADA

Abstract

Antimicrobial use was measured for 17 months on dairy farms that participated in the Canadian Bovine Mastitis Research Network in Alberta. In total, 1490 cows were present on 13 farms. Forty different products were found that contained 19 different ingredients. In total, 14.5 grams of active ingredient was used per cow per year and 65.1% was administered by injection and 25.1% was used for intra uterine infusion. The remaining part was infused intramammarily, used as medicated feed, or applied orally. The most frequently used active ingredient were Trimetroprim Sulfonamid (30%), tetracyclines and oxytetracyclines (38%). Penicillins contributed 11% to the total amount. Herd size was negatively correlated with antimicrobial use.