2013 Annual Report
1a.Objectives (from AD-416):
Collect serum and biopsy samples from a dairy herd with a high prevalence of papillary digital dermatitis.
1b.Approach (from AD-416):
Serum samples and individual animal records will be collected for serologic assays evaluating humoral responses to pathogens postulated to contribute to the development of papillomatous digital dermatitis. Individual animal records will be evaluated to correlate lesion development to serologic data. Punch biopsy samples will be collected from lesions of PDD and paired samples from non-lesion areas for bacteriologic and molecular analysis. It is hope that this project will facilitate understanding of the pathogenesis of PDD.
Digital dermatitis is an ulcerative skin lesion affecting the bovine hoof. Lesions are painful, reoccurring, and can affect a large percentage of the herd. Treponemes have been routinely isolated from lesions; however, experimental inoculation with pure culture failed to result in disease. Studies combining culture, serology and metagenomic analysis are being conducted to evaluate bacterial species involved in lesion development. This project was undertaken to obtain samples from both healthy and cows demonstrating lesions of digital dermatitis.
Samples and data were collected by staff at South Dakota State University and sent to NADC. Bacterial isolates from the samples were archived for later identification and analysis. Further analysis will be conducted at NADC. FY2013 concluded the collaborative portion of the project.