Relations Between Macroscopic Appearance, Histopathologic Changes and Bacterial Diversity in Digital Dermatitis Lesions

Digital dermatitis (DD) is the foot lesion with the largest impact on welfare in Danish dairy cattle. DD appears to have different macroscopic characteristics in different herds. Furthermore, there is a variation in prevalence and morbidity of DD between herds. Since the aetio-pathogenesis of DD still is uncertain, and DD microscopically appears to be multibacterial, often with spirochetes as the predominant bacteria found in the deeper layers of epidermis, there may be a relation between the macroscopic and histopathologic appearance and the bacteriologic findings. The objective of this study was to evaluate relationship between macroscopic and histopathologic characteristics and the bacteria present in the lesions. Based on 55 DD lesions of 44 cows the relationship between pathologic and bacterial diversity was analysed. There was no tendency towards specific phylotypes of Treponema or combinations of phylotypes of Treponema caused specific pathological changes ...