Efficacy of oxytetracycline for treatment of papillomatous digital dermatitis lesions on various anatomic locations in dairy cows

Objective--To evaluate efficacy of topical treatment with oxytetracycline solution among dairy cows with papillomatous digital dermatitis (PDD) lesions on the interdigital cleft, heels, or dewclaw. Design--Clinical trial. Animals--70 dairy cows from a single herd. Procedure--On the basis of anatomic location of PDD lesions, cows were allocated into 1 of 3 groups (interdigital cleft [n = 14], heels [30], or dewclaw [26]) and treated topically with oxytetracycline solution. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion size scores were recorded. Results--On the basis of pain and lesion size scores, oxytetracycline appeared significantly less effective among cows with lesions on the interdigital cleft than for cows with lesions on the heels or the dewclaw. Number of cows with signs of pain or visible lesions after treatment was significantly higher for cows with lesions on the interdigital cleft than for cows with lesions on heels or the dewclaw. Conclusions and Clinical Relevance--Anatomic location of PDD lesions has an effect on the efficacy of topical treatment with oxytetracycline solution in dairy cows affected with PDD, Cows with lesions on the interdigital cleft were less likely to respond to treatment, compared with cows with lesions on the heels or the dewclaw.