Teat apex coliform populations and coliform mastitis--a herd study.

A dairy herd having a high incidence of coliform mastitis was observed by means of pre- and post-milking samples and teat apex culture. Infected quarters were the major source of teat apex contamination with coliform bacteria and therefore constituted a risk to unifected quarters and to other cows. Coliform populations on the apex from environmental sources appeared to be transitory.