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.