THE IMPORTANCE OF HOOF TRIMMING DATA IN CLAW LESION INVESTIGATIONS

Claw lesions are the primary cause of lameness in dairy cattle, with serious implications for animal welfare due to the distress and discomfort experienced by the cows. Claw lesions are classified as either infectious lesions such as digital dermatitis, interdigital dermatitis, heel erosion, and interdigital phlegmon, or non-infectious lesions (including white line disease, sole ulcer, and sole haemorrhage). The majority of studies have reported digital dermatitis, sole haemorrhage, sole ulcer, and white line disease as the primary causes of dairy cattle lameness. There are several risk factors that influence the prevalence of claw lesions in dairy cattle, including environmental factors, design of housing facilities, and hygiene and management practices. There is also a heritable component to claw lesions that has probably been underestimated due to the poor quality of recording. Despite an increased awareness of lameness, its major causes have remained unchanged over the past 30 years, with a continued increase in the occurrence of lameness in dairy herds. Minimising the occurrence and impact of lameness is one of the greatest challenges for the dairy industry.

Claw trimming is used as a management tool to control claw lesions. In South Africa, claw data are limited to the use of private hoof trimmers, who record lesions on paper, and data is not necessarily captured in an electronic recording system. In the study cited, routine trimming data from five intensively managed dairy farms over a 6-year period (2014–2019) were analysed to investigate the prevalence and distribution of claw lesions in Holstein cattle in the central region of the country in order to facilitate more effective recording and management.

Lesion identification followed the Claw Lesion Identification in Dairy Cattle brochure. Among the recorded lesions, digital dermatitis had the highest prevalence (64.02%), followed by sole ulcers (8.59%), white line disease (6.27%), and sole haemorrhage (4.28%), and most lesions occurred in the rear feet. Chi-square tests and correspondence analysis were employed to explore the relationships between lesions, feet, and housing. Results indicated that the prevalence of sole ulcers and sole haemorrhage showed high similarity for foot and lesion association, and that they were more highly associated with the rear feet. Additionally, the prevalence of digital dermatitis and interdigital phlegmon were strongly associated, and closely associated with sole ulcers, and all these lesions were associated with both feedlot and free-stall housing systems. The correspondence analysis further confirmed a close association between white line disease and sole haemorrhage, and the prevalence of these lesions in the combination housing system.

In conclusion, the results not only highlighted the complexity of lesion data but also indicated that specific associations between different lesions could lead to simplifying the recording thereof. It is therefore important that the description and recording of claw lesions are made as easy as possible for accurate and consistent recording. Consolidating the most informative claw lesions into categories will aid in the practical prevention, management, and treatment of lameness on-farm.