Objective—To compare efficacy of a topically administered
nonantimicrobial cream with that of lincomycin
for treatment of digital dermatitis in dairy cattle.
Design—Randomized clinical trial.
Animals—98 cows from a commercial Holstein dairy
Procedure—Cows with active lesions of digital dermatitis
identified on a single observation day were
randomly assigned to receive a nonantimicrobial
cream, lincomycin paste, or no treatment. Cows were
examined approximately every 4 weeks for 130 days
after treatment for lesion maturity score, score for
signs of pain, lesion size, and lesion activity.
Results—29 days after a single treatment, both treated
groups had significantly reduced scores for signs
of pain, lesion activity, lesion size, and the decision to
retreat, compared with findings in the untreated
group. Efficacy of the 2 treatments was not significantly
different for decreasing pain score or lesion
activity or for increasing lesion maturity score, but lincomycin
was significantly more efficacious in
decreasing lesion size and avoiding retreatment. By
use of multivariate logistic regression, lactation number
was a significant treatment effect modifier on the
outcome of a healed lesion after treatment. Cows
with ≥ 3 lactations were more likely to have a healed
lesion at 29 days, compared with first- and secondlactation
Conclusions and Clinical Relevance—Because
antimicrobial treatments for digital dermatitis in cows
require a veterinarian's prescription, the nonantimicrobial
cream could serve as a viable but less consistently
effective alternative to antimicrobials and could
be applied by veterinarians, hoof trimmers, and others.
(J Am Vet Med Assoc 2001;219:1435–1438)
Amajor animal welfare issue facing the livestock industry is the care, handling, and transport of nonambulatory cattle. Consumers, researchers, practitioners, and animal protection organizations have questioned the quality of care provided to and management of nonambulatory cattle and raised questions about possible food safety concerns. Veterinarians and producers continue to be challenged with providing quality care for nonambulatory cattle. In addition, veterinarians are recognized as a credible source of information for consumers, regulators, and policy makers. Thus, it would be beneficial to provide peer-reviewed information to practitioners and others who must make clinical and policy decisions.
Objective—To compare the effectiveness of lincomycin and oxytetracycline for treatment of digital dermatitis (DD) in dairy cows through gross visual examination, histologic evaluation, and bacteriologic evaluation.
Design—Randomized controlled clinical trial.
Animals—25 cows with DD lesions from a commercial Holstein dairy herd.
Procedures—Cows with DD lesions were randomly assigned to 1 of 3 groups: topical treatment with 10 g of lincomycin hydrochloride (n = 11), topical treatment with 10 g of oxytetracycline hydrochloride (11), and no treatment (3) on days 1 and 2 (d1). Biopsy specimens were obtained for histologic examination from DD lesions prior to treatment and 28 or 31 days (d30) after treatment for histologic examination. Cows were clinically examined on d1, days 12 or 14 (d14), and d30.
Results—No difference was evident in clinical responses to lincomycin and oxytetracycline, so data were pooled; at d30, 8 of 11 of lincomycin-treated lesions and 7 of 11 oxytetracycline-treated lesions appeared visually healed, respectively. Gross visual examination suggested 73% (16/22) of treated cows were healed at d14 and 68% (15/22) of treated cows were healed on d30. Of the 15 lesions that appeared healed on d30, 7 of 15 were classified histologically as active (ulceration and bacterial invasion; 2/15) or incipient (5/15).
Conclusions and Clinical Relevance—Clinical responses to lincomycin and oxytetracycline did not differ. Agreement was good between gross visual and histologic assessments of DD lesions before treatment; agreement 1 month after treatment was variable. Histologic evaluation could not distinguish incomplete healing from lesion recurrence.