Diagnosis, treatment, and control of bovine digital dermatitis in dairy cattle

Abstract

This thesis focuses on the detection, prompt effective treatment, and control of digital dermatitis (DD) on dairy herds. In Chapter 2, an overview of the status quo on management of DD on dairy herds is given. In Chapter 3 we demonstrated that experienced scorers are well able to differentiate between photographs of feet affected by DD and photographs feet unaffected by DD. On the other hand, they were less able to identify specific lesion stages, including the M2 and M4 stage which are considered important stages regarding clinical impact and infection reservoir, respectively. In Chapter 4 we concluded that infrared thermography (IRT) is unlikely to be suited for automated identification of feet affected by DD due to the poor associations between maximum temperature of the plantar pastern region and the presence of M2 lesions or DD lesions in general. In Chapter 5 we demonstrated that topical treatment of active, often painful, DD lesions with a copper and zinc chelates gel (coppergel) and bandage outperformed an enzyme alginogel and bandage in M-score improvement, with the majority of lesions transitioning to the chronic, often not painful, state. In contrast, treatment with the alginogel achieved improved wound healing progress compared with the coppergel. However, neither the coppergel nor the alginogel achieved high cure rates to healthy skin. In Chapter 6 we illustrated that a standalone identification of risk factors for DD together with associated advice to control these risk factors is insufficient to decrease the prevalence of DD in dairy herds. Chapter 7 concludes this thesis with a general discussion providing a reflection on insights gained and suggestions for future research on the diagnosis, treatment, and control of digital dermatitis in dairy herds.