Epidemiology of teat lesions in a dairy herd. II. Associations with subclinical mastitis.

Even small teat lesions are significantly associated with subclinical mastitis and the risk of mastitis increases as the lesions approach the teat canal. Analyses show that at least 7% of cases of subclinic mastitis would have been avoided if no teat lesions had occurred in the herd in question. Analyses also indicate that the risk of mastitis in a quarter increases by about 50% across a 10 months follow-up period (equivalent to one lactation period) after the teat has been injured.