In his past 30 years of hoof trimming, Vic Daniel has seen digital dermatitis (DD) become by far the most common hoof lesion in his clients’ herds. Vic has kept detailed records of the claws he has trimmed—for the past 7 years using the Hoof Supervisor® lesion recording system. Here are what Vic has concluded are the main risk factors for DD.
Researchers at the University of Wisconsin evaluated the hoof health of 719 heifers for 6 months prior to first calving. In the subsequent lactation, heifers with pre-partum digital dermatitis (DD) had lower milk production, poorer conception to first service, longer days open and were more likely to have multiple cases of DD.
Non-healing (nh) bovine hoof horn lesions, characterized by penetration of the horn capsule and association with white line disease (nhWLD) and sole ulcers (nhSU) are frequently encountered in dairy herds endemically affected by digital dermatitis (DD). Lesions of this type are associated with more severe lameness, often leading to claw amputation or slaughter and they respond poorly to standard DD treatment. Researchers in Austria recently described a successful therapy for such lesions.
Zinpro has recently released a new DD Check App that facilitates recording of DD lesions across an entire group of animals. Once the required information on individual cows has been entered, a ‘DD Infection Model’ can be used to summarize DD infection status and predict future outbreaks.
In an interview with the veterinary journal InPractice, renowned dairy hoof health specialist Roger Blowey discusses cattle lameness and current thinking about the causes and control of digital dermatitis (DD).
The British Columbia Dairy Hoof Health Group has created HARP-DD (Hoof Assessment and Recommended Practices for Digital Dermatitis Control), a risk assessment tool aimed at helping to reduce the prevalence of digital dermatitis (DD) by identifying and addressing on-farm risk factors for infection.
Few claims about the efficacy of products used to treat digital dermatitis (DD) are supported by any conclusive scientific evidence. Not all treatment trials provide conclusive evidence – many reported trials are poorly designed, leading to bias towards a particular outcome.
A recent study considered a large number of DD treatment trials, eliminating all but four that were rigorously designed to give conclusive, unbiased results.
Researchers at the University of Wisconsin have demonstrated that acute digital dermatitis (DD) in 16 – 25 month old heifers can increase heel height, claw angle and depth of the interdigital cleft. DD lesions were also associated with significant increases in heel horn erosion.
Previous studies have demonstrated that multiple bacterial species are associated with digital dermatitis (DD) lesions, with spirochetes being the most commonly identified organism. A recent study at Iowa State University demonstrated that, although spirochetes are the predominant bacteria present in the later stages of lesion development, many other bacterial species are involved in the earlier stages.
With digital dermatitis (DD) now being implicated in non-healing hoof lesions, its control is becoming more important than ever. Footbathing remains the key way of controlling DD infections on-farm, according to British veterinarian Sara Pedersen who says:
“Digital dermatitis is often described as ‘mastitis of the foot’, so foot bathing can be considered the equivalent to teat dipping in mastitis control. It can also help harden the hoof and make it less susceptible to penetrating injuries or shearing forces.”