The coliform mastitis causes severe losses on dairy farms. Traditional strategies based on prophylaxis and control programs are not sufficient in some cases. New tools have emerged in order to increase the immunity of animals with emphasis on vaccines for mastitis. The aim of this study was to determine the effects on milk quality, on the infectious status of cows and the use of systemic antimicrobial therapy after the use of a mastitis multivalent vaccine (STRARVAC®, HIPRA) in a farm with serious problems of coliform mastitis.