The Milk Withholding Time of Salicylic Acid for Treatment of Digital Dermatitis in Dairy Cattle

Abstract

Digital dermatitis is a top cause of lameness in dairy cattle that results in ulcerative lesions on the feet. Topical salicylic acid has been shown to provide similar efficacy to the antibiotic drugs used previously, but there is no milk withholding time established in the United States. The objective of this study was to provide data in order to establish this withholding period. A secondary objective was to evaluate outcomes among treatments. Treatment groups were topical applications of the following drugs: salicylic acid paste, salicylic acid powder, and tetracycline. The lesions were scored at day 0, day 7, and day 28 post-treatment. Milk samples were collected the day before treatment, 4 hours, 8 hours, 24 hours, 36 hours, and 48 hours post-treatment. Results indicated that most cows did not show detectable levels of salicylic acid after 24 hours.