Treatment for bovine Escherichia coli mastitis – an evidence‐based approach

Suojala, L., Kaartinen, L., Py€or €al €a, S. Treatment for bovine Escherichia colimastitis – an evidence-based approach. J. vet. Pharmacol. Therap. doi:10.1111/jvp.12057.Bovine mastitis caused by Escherichia coli can range from being a subclinicalinfection of the mammary gland to a severe systemic disease. Cow-dependentfactors such as lactation stage and age affect the severity of coliform mastitis.Evidence for the efficacy of antimicrobial treatment for E. coli mastitis is verylimited. Antimicrobial resistance is generally not a limiting factor for treat-ment, but it should be monitored to detect changes in resistance profiles. Theonly antimicrobials for which there is some scientific evidence of beneficialeffects in the treatment for E. coli mastitis are fluoroquinolones and cephalo-sporins. Both are critically important drugs, the use of which in animals des-tined for food should be limited to specific indications and should be based onbacteriological diagnosis. The suggested routine protocol in dairy herds couldtarget the primary antimicrobial treatment for mastitis, specifically infectionscaused by gram-positive bacteria. In E. coli mastitis with mild to moderateclinical signs, a non-antimicrobial approach (anti-inflammatory treatment, fre-quent milking and fluid therapy) should be the first option. In cases of severeE. coli mastitis, parenteral administration of fluoroquinolones, or third- orfourth-generation cephalosporins, is recommended due to the risk of unlimitedgrowth of bacteria in the mammary gland and ensuing bacteremia. Evidencefor the efficacy of intramammary-administered antimicrobial treatment forE. coli mastitis is so limited that it cannot be recommended. Nonsteroidal anti-inflammatory drugs have documented the efficacy in the treatment for E. colimastitis and are recommended for supportive treatment for clinical mastitis.(Paper received 10 October 2012; accepted for publication 19 April 2013)L. Suojala, Department of Production Animal Medicine, Faculty of VeterinaryMedicine, University of Helsinki, Paroninkuja 20, FI-04920 Saarentaus, Finland.E-mail: leena.suojala@mtk.fi