BHACHITIS. 269 



the latter is removed from the bones of an animal in this condi- 

 tion certain portions of the bony tissue come away and remain 

 attached to the membrane. This is especially noticeable between 

 the epiphyses of the vertebrae. The inner layer of the periosteum 

 is thickened and the diseased tissue seems to have undergone a 

 spongy degeneration. Inside of the bone we find it soft and 

 cavernous. 



Clinical Symptoms and Course. The first appearance of 

 rickets is gradual, and generally the veterinarian is not consulted 

 in the early stages, but only when the skeleton shows marked 

 alterations of form, especially in the bones of the extremities. 

 We find periosteal inflations in the frontal bone and bones of the 

 temple, so that the head shows a peculiar marked alteration. 

 Schiitz has found that in rhachitic animals the bones of the skull 

 are extremely thin and the sutures separated. In the thorax there 

 is a weakening of the walls of the chest, and the animals present 

 that one-sided or " chicken-chest" condition. There is a peculiar 

 knot-like swelling of the ribs both at their upper extremities where 

 they unite with the vertebrae, and in their inferior extremities 

 where they unite with the sternum and false ribs. 



In this latter condition there forms a series of small, round 

 nodules known as "rhachitic bead-string." In acute forms of 

 this disease the spinal cord is twisted or bent in different directions. 

 The most striking alterations are observed in the extremities. The 

 long bones are thickened at both ends and bent on account of the 

 softness of the bone and pressure of the weight of the body when 

 standing. The upper portion of the front legs bends inward, 

 rarely outward, and the animals have a peculiar, unsteady, awk- 

 ward gait. They stand on the hind legs with the leg twisted 

 under them, and in aggravated cases the bones are bent in a circle, 

 the bend of the astragalus coming down on the ground. As a 

 consequence of the altered position of the bones tlie ligaments 

 become distended and stretched, causing an inflammation of the 

 joints, consequently more or less enlargement of them. At the 

 same time we observe emaciation, loss of appetite, and in some 

 cases catarrh of the stomach and air-passages. The disease, as a 

 rule, is chronic and the prognosis is unfavorable. If the dis- 

 ease is taken early, it may be checked by means of proper feeding; 

 but when the deformity is once formed, it is only in extremely rare 



