Digital dermatitis is an infectious disease that causes lameness in dairy cattle, a primary welfare concern of the dairy industry. One of the common treatments for this painful hoof disease is through the application of an antibiotic bandage that must be removed following treatment. The objectives of this randomized clinical trial were to determine if topical application of tetracycline hydrochloride in a paste would be as therapeutically effective for the treatment of digital dermatitis as a powdered form of tetracycline hydrochloride held in place by a bandage, and to quantify pain associated with digital dermatitis lesions. Two hundred and fourteen Holstein cow hooves with digital dermatitis lesions were randomly assigned to 1 of 3 treatments: a tetracycline hydrochloride paste, tetracycline hydrochloride powder held in place with a bandage for 2. d, or a negative (untreated) control. Lesions were examined at 2 time periods: 3 to 7. d posttreatment and 8 to 12. d posttreatment to determine healing rates. Nociceptive thresholds were measured using a pressure algometer to quantify the pain at the lesion site. The tetracycline hydrochloride paste was as effective as the powdered bandage treatment in terms of healing rates, with 47.4 and 57.1% hooves healed at 8 to 12. d posttreatment, respectively. Both treatments were more effective than the control, in which no lesions healed 8 to 12. d following initial examination. Mean (±SE) nociceptive thresholds for active, healing, and healed lesions differed, with limb-withdrawal response occurring at 7.45 (±0.67) kg, 12.84 (±1.85) kg, and censored to 25. kg (maximum value of algometer) of force applied, respectively. However, active lesions were not consistently associated with pain, as maximum force was tolerated when applied to 19% of active lesions, perhaps due to variability in stoicism between individual cattle or due to changes in pain during the progression of infection. In conclusion, tetracycline hydrochloride paste was as effective as tetracycline hydrochloride bandage, eliminating the need for bandage removal following treatment application. Digital lesions can be painful during both active and healing stages, suggesting the need for treatment and husbandry interventions for pain mitigation.
Bibliographical noteFunding Information:
The authors thank Laura Wright and the staff at the Elora Dairy Research Centre (Elora, ON, Canada) for technical assistance with the trial, Rob Swackhammer (Swackhammer Veterinary Services, Rockwood, ON, Canada) and Lisa Baarda (Cramer Mobile Bovine Veterinary Services, Stratford, ON, Canada) for assistance with hoof examinations, and William Sears at the University of Guelph (Guelph, ON, Canada) for assistance with statistical analysis. Additionally, Chuck Guard (Cornell University, Ithaca, NY) is thanked for promoting use of a paste formula for digital dermatitis treatment. Funding for this project was provided by the National Sciences and Engineering Research Council of Canada (Ottawa, ON, Canada) and Dairy Farmers of Ontario (Mississauga, ON, Canada).
- Digital dermatitis
- Pressure algometry
- Tetracycline hydrochloride