Evaluation of Potassium Monopersulfate Footbath Solution for Controlling Digital Dermatitis in Lactating Dairy Cattle: A Randomized Clinical Trial

The objective was to assess potassium monopersulfate as a disinfectant used in footbath to control digital dermatitis (DD) in dairy cows. We hypothesized that a potassium monopersulfate solution would control DD. A 180-day randomized clinical trial was conducted in a 265-Holstein free-stall facility. Throughout the trial, foot bathing was performed bi-weekly using a split (left vs. right feet) footbath: one tub filled with 1% potassium monopersulfate (treatment), the other with tap water (control). DD lesions were scored during trimming chute examinations of the unwashed hind heels (sampling units) every 90 days using the modified M-scoring system. DD lesions were re-categorized into four variables: 1) inactive; 2) active; 3) any; 4) inactive or no DD lesions. Three longitudinal outcomes were characterized: risks of 1) developing a DD lesion; 2) reactivating an inactive DD lesion; 3) curing a DD lesion. A generalized linear model was used to compare the variables and longitudinal outcomes between treated and control groups. Prevalence of active DD lesions increased from 12.5% to 39.9% between days 0 and 90. This significant increase in prevalence justified the discontinuation of the study on day 90 for ethical reasons. There was no statistical difference between treated and control groups in the risks of developing a new DD lesion (RR: 1.0; 95% CI: 0.62, 1.7), reactivating an inactive DD lesion (RR: 1.0; 95% CI: 0.62-1.7); or curing a DD lesion (RR: 0.88; 95% CI: 0.37, 2.1).  A 1% potassium monopersulfate footbath solution appears ineffective to control DD in this study.