Milk leg is not a term commonly used in veterinary medicine. However, there is a condition called Chronic Progressive Lymphedema (CPL) that affects some breeds of draft horses, and it is characterized by a buildup of lymph fluid in the lower legs that results in progressive swelling. The disease is progressive, and it begins below the fetlock and gradually moves up the leg. All legs are affected, with the hindlimbs usually more seriously so. The initial signs include thickening, crusting, and folding of the skin, which may be hidden by the long hair (feather) on the horses lower legs. Affected areas are itchy, causing the horse to stamp its feet and rub its legs, and painful, so that the horse may be reluctant to allow its legs to be touched. The quality of the hoof is often poor, and hooves are prone to cracks, splits, and the development of thrush and abscesses. Horses may also develop laminitis, and chestnuts and ergots are often misshapen and irregular.
CPL is primarily observed in draft horse breeds such as the Shire, Clydesdale, Belgian, Gypsy cob, and Friesian, and signs are usually only seen in horses older than two years. Both sexes are affected. There is no cure for CPL, and the aim of treatment is to manage the condition. Horses with CPL often have poor-quality hooves, so regular trimming is required to help keep the hoof healthy.
