Comments on proliferative pododermatitis in horses

I read with interest the recent Pathology in Practice article describing a 13.5-year-old Belgian gelding with coronary band dystrophy and proliferative pododermatitis.¹ In the Comments section, the authors discuss whether the horse had proliferative pododermatitis secondary to coronary band dystrophy or had concurrent canker. They cite 2 references describing horses with canker in which spirochetes were identified in lesions, and report that no spirochetes were identified with silver histochemical staining of biopsy specimens from the horse described in their report.

Another interesting association with canker not mentioned by the authors can be found in the study by Brandt et al,² who report that they were consistently able to find bovine papillomaviruses type 1 and 2 in samples from horses with canker. In their study,² use of a conventional PCR assay revealed bovine papillomaviruses type 1 and 2 DNA in 24 of 24 hoof cankers but yielded negative results for samples from 13 horses without signs of canker. I believe that looking for bovine papillomavirus DNA in tissues from the horse described in the report by Twitchell et al¹ could have added some very useful additional information.

Richard Estes, dvm

Ocala, Fla

The authors respond:

We thank Dr. Estes for his comments regarding our recent Pathology in Practice article describing coronary band dystrophy and proliferative pododermatitis in a Belgian gelding.¹ The goal of our report was to raise awareness of coronary band dystrophy. We did not test for bovine papillomavirus type 1 or type 2 when the horse underwent a clinical workup or necropsy because these tests were not readily accessible. Nevertheless, we agree that knowledge regarding the presence or absence of these viruses in diseased and normal tissues of this horse could have provided useful information. Further research is needed to determine the role that bovine papillomaviruses play in equine canker. We will assess the feasibility of testing tissues from this horse obtained from areas of proliferative pododermatitis and coronary band dystrophy, along with samples of grossly normal skin, for bovine papillomavirus DNA with the technique described by Taylor et al² for formalin-fixed, paraffin-embedded tissues.

Erica L. Twitchell, dvm, ms

Department of Biomedical Sciences and Pathobiology Virginia-Maryland College of Veterinary Medicine Virginia Polytechnic Institute and State University Blacksburg, Va

Richard A. Hartman, dvm, ms

Mid-Rivers Equine Centre Wentzville, Mo

Sarah J. Waxman, dvm, ms

Timothy B. Lescun, bvsc, ms

Sandra D. Taylor, dvm, phd

Veterinary Teaching Hospital Department of Veterinary Clinical Sciences

Margaret A. Miller, dvm, phd

Animal Disease Diagnostic Laboratory Department of Comparative Pathobiology College of Veterinary Medicine, Purdue University West Lafayette, Ind

The potential benefits of declawing should not be dismissed out of hand

During its regular annual session this past July, the AVMA House of Delegates revised the AVMA policy on declawing of domestic cats to clarify that onychectomy involves amputation of all or part of the distal phalanges, acknowledge that cats with claws may pose health risks to certain owners, and recognize that declawed cats may be safely allowed outdoors if they are appropriately supervised.¹

I support the AVMA's most recent attempt to address declawing of domestic cats but would further suggest that at least some of the criticism of declawing may arise from a belief that this procedure does not provide any benefits to cats and only creates problems.

The AVMA policy states that “cats that have destructive scratching behavior are more likely to be euthanatized, or more readily relinquished, released, or abandoned.” However, this doesn't take into account cats that remain in the home but may be punished futilely because of objectionable scratching behavior. Certainly, this is not a good situation for these cats or their owners.

I submit that a potentially more broadly applicable benefit of declawing is the better care that cats may receive, both in the veterinary clinic and at home, as a result of this procedure.

Throughout the 34 years of my veterinary career, I have often found that examining and treating cats with claws can be difficult or even impossible without severe restraint or sedation. Even though veterinarians and their staff should be prepared to work with fractious cats, if we can examine and treat cats more thoroughly and more easily because the danger of handling them is reduced, then certainly this is a benefit to the cats as well as to ourselves.

And, what of our clients? How many cats are not receiving appropriate medical and grooming care at home because they use their claws to ward off this necessary attention? My staff and I have spent tremendous amounts of time advising clients on how to provide this type of care to cats and neutralize their claws. Even so, I found that when I first began daily toothbrushing with one of my cats, the cat would dig its claws into my hand while trying to push the toothbrush away. As an experienced veterinarian, I worked through this, but realized that there are likely many cats in homes where this behavior would have been perceived as an insurmountable obstacle. Those cats are not getting their teeth brushed. And how many of those cats are not receiving other types of care because their claws are an effective deterrent?

One can counter with objections and alternatives to declawing, but I don't think the potential benefits of declawing should be dismissed out of hand.

Kenneth M. Kornheiser, dvm

Countryside Veterinary Clinic Plainwell, Mich