Randomised clinical trial showing the curative effect of bandaging on M2-stage lesions of digital dermatitis in dairy cows.

Objectives and design: This trial evaluated the effect of bandaging of acute painful ulcerative bovine digital dermatitis (DD) lesion (stage M2) in dairy cows, tested using two different topical treatments.

Design: Randomised clinical trial.

Setting: This study was conducted using Holstein-Friesian cows ranging in age from heifers to fourth lactation in a single dairy herd and diagnosed with acute ulcerative DD lesions (stage M2) on the first examination (week 0). Cows were randomly assigned into either a non-bandaged or bandaged group across two treatment conditions: topical chlortetracycline spray (CTC) and Intra Hoof-Fit Gel (IHF). Lesions received standardised bandaging and treatment on a weekly basis. Unhealed lesions could receive up to five repeated treatments, at weekly intervals, within a four-week period. Both M-stage and locomotion were also evaluated and scored weekly. Cows with healthily formed skin (stage M0) were deemed healed and subsequently released from the study.

Results: In total, 163 M2 lesions were diagnosed at week 0. Bandaged M2 lesions had a significantly higher probability of cure than non-bandaged lesions regardless of treatment type (HR: 4.1; P<0.001; 95 per cent CI: 2.5 to 6.8). Most healing occurred within the first three weeks of trial. Furthermore, bandaged lesions (group 2 and group 4) were significantly less likely to progress into the chronic hyperkeratotic or proliferative stage (M4) than non-bandaged lesions in group 1 and group 3 (HR: 0.10; P<0.001; 95 per cent CI: 0.04 to 0.22). Out of concern for the cow's wellbeing, this study investigated the effects of bandaging on locomotion. Bandaging had no effect on locomotion for either cows treated with CTC (group 1: median Sprecher score, 2; IQR=1-2; group 2: median Sprecher score, 2; IQR=1-3; P=0.3) or IHF (group 3: median Sprecher score, 2; IQR=1-2; group 4: median Sprecher score, 2; IQR=1-3; P=0.3).