CA calves are normally born alive and most can walk, suckle and survive. Contractures which reduce the range of angular movement of the upper limb joints are present at birth in CA affected calves. Due to these contractures, at birth CA calves assume an abnormal crouched posture, resembling an elk or deer fawn, with the feet placed more to the rear than normal, hocks pulled up and back and the spine slightly arched. In their first days of life, CA calves are also flat down on their pasterns. Although there is a reduced range of movement (“contracture”) in the upper limb joints, particularly the hip, stifle and hock, there is an increased extensibility of the lower limb joints, particularly the pasterns. CA affected calves can show significant recovery and usually appear relatively normal by 4 to 6 months of age. As weanlings and yearlings, CA calves appear lighter framed and lighter muscled, particularly in the hindquarters. Most perform poorly and remain tall, slender animals with poor foot conformation.
– By David Steffen DVM Ph.D., University of Nebraska