BOVINE LAMENESS - TYPES & CAUSES
Despite the growing amount of awareness around bovine lameness, the causes are still many and varied, and often difficult to identify. Types of lameness fall into two categories: disease and injury. Less commonly, lameness can be caused by injuries higher up the leg or back including fractures, nerve damage, arthritis, ligament rupture, hip dislocation, spinal injury and mastitis. But the vast majority of injuries are found in the claw. Within the claw, lameness can result from white line disease, sole injury, abscess, bruising or septic arthritis. DairyNZ says poor cow management is responsible for many of the cases of bovine lameness in New Zealand, with an increase in staff training in lameness prevention key to turning this around. When it comes to disease, footrot is still the most common infectious cause of lameness. Bacteria commonly found in soil and manure can breach the protective barrier of the skin and cause a painful, necrotic infection between the toes. Abrasions and constantly wet conditions increase the likelihood of footrot forming. However, bovine digital dermatitis (BDD), a highly infectious skin disease which is a significant cause of lameness in housed cattle overseas, was identified in New Zealand in 2011 and cases are on the rise. BDD is usually introduced by buying in infected cows, and spreads from cow to cow where foot hygiene is poor. Muddy entrances and exits, feed pads and housing systems have all been implicated.