Sustainable = Sound. Facilitating lameness control in sheep flocks
Lameness impacts performance with subsequent reduction in efficiency and the treatment of infectious lameness is the primary reason for antimicrobial use in sheep. It is therefore not surprising that reducing lameness in sheep is a priority of the Animal Health and Welfare Pathway for improving sustainability. Lameness is a dynamic problem. To devise a flock specific control plan requires the assessment of lameness prevalence in flock, a review of medicines usage, an appraisal of the main aetiology and risk factors for the flock and an understanding of the limitations and barriers to a farmer putting in place lameness control interventions. Most lameness is caused by infectious agents. Dichelobacter nodusus is necessary to initiate footrot and Treponeme spp. are consistently present in Contagious Ovine Digital Dermatitis (CODD) lesions but both diseases are polymicrobial and D. nodosus is implicated in the development of CODD. Footrot vaccination, in conjunction with other control measures such as culling repeatedly lame sheep and treating lame sheep promptly, can reduce lameness incidence and the number of antibiotic treatments required in flocks where lameness is above target prevalence and primarily driven by footrot.