Efficacy of Quaternary Ammonium Salt-Based Disinfectant or Chelated Copper-Zinc Footbath Solution in the Treatment of Digital Dermatitis on One Research Dairy Farm in Taiwan.

BACKGROUND:Footbaths can be used to manage digital dermatitis (DD), a common cause of lameness in dairy cattle. Copper sulfate and chelated copper-zinc (CZS) solutions in footbaths are potentially harmful to the environment.HYPOTHESIS/OBJECTIVES:To determine if a quaternary ammonium salt-based disinfectant (QASD) footbath is as effective as a chelated CZS solution in controlling DD in dairy cows.ANIMALS:Fifty-one lactating Holstein cows were randomly assigned to one of two treatment groups, with DD status based on the M-stage scoring system and locomotion score balanced between treatment groups.MATERIALS AND METHODS:The groups were treated with a 1% QASD or a 2.5% chelated CZS. Footbaths were performed once per week for 15 weeks. Logistic regression was used to analyse clinical improvement. All cows received appropriate medical treatment for DD and other hoof diseases.RESULTS:Clinical improvement rates were 67% in the QASD group and 38% in the CZS group (p = 0.03). Logistic regression analysis showed that the odds (95% confidence interval) for clinical improvement rate in the CZS group were 0.30 (0.095-0.948) times that of the QASD group (p = 0.04). The M0 score in the QASD and CZS groups increased significantly (p < 0.05) at the end of the 15 week study period. In the QASD group, the proportion of M2, M3 and M4 scores were significantly decreased (p < 0.05).CONCLUSION AND CLINICAL RELEVANCE:Over a 15 week period, QASD for footbathing was associated with a lower prevalence of active DD lesions than when using CZS.