Digital dermatitis (DD) is a painful skin condition currently considered to be the leading cause of infectious lameness in dairy cattle. The overall objective of this project was to investigate novel and existing methods of detecting DD to be used by farmers and researchers to monitor the disease, and to investigate the impact of farmers? prevention and treatment strategies on disease prevalence. Visual inspection of lesions in the parlour was found to be a practical and reliable method for detecting and classifying DD. In addition, thermography was identified as a potential tool for the detection of cattle foot disorders. Validating such methods for detecting DD is important because locomotion scoring alone was not found to be sufficiently sensitive to identify cows with DD. In a further study a novel ethogram approach validated several specific behaviours associated with DD. A telephone survey was carried out to establish the nature and scope of management strategies farmers use to control DD. The two main strategies identified in the survey were 1) whole herd footbathing and 2) an individual treatment approach. A one year observational study on fifteen farms used the inspection method developed in the parlour to investigate the impact these two approaches had on disease prevalence. It was found that as herd size increased, footbathing became far less effective in maintaining a low prevalence than treating cows individually. Farmers use a variety of methods in an attempt to control DD on their farms, with different levels of emphasis placed on the priority and regularity of prevention and treatment. An outcome of this study is a DD monitoring approach farmers can use, to routinely assess the effectiveness of prevention and treatment strategies. In addition, results indicate that as herd size and disease prevalence increase, individual treatment is imperative for therapeutic resolution of DD.
|Date of Award||2011|