Dysostosis enchondralis of the ulnar bone in the basset hound.

Ninety-four Basset Hounds were examined for the clinical features, the radiographical changes and the nutritional and hereditary possibilities connected with the development of decreased longitudinal growth of the ulnar bone. In six puppies the possibility was examined of the development of the disease being due to overloading of the foreleg. Ten of the dogs were examined for gross pathology and 4 by histology post mortem. Clinical symptoms and radiographical changes were not seen until the age of 31/2 months. In all cases there were broadening of the joint space in the elbow joint and degeneration of the articular cartilage at the semilunar notch. An abnormally broad and irregular growth plate was seen in the affected young dogs, and histology revealed obvious abnormalities in the growth plate located in the zone of resting cartilage indicating degenerative disturbances in the cartilage. There were no signs of rickets, and it was not possible to demonstrate that the disease was caused by misleading. It is concluded that the disease corresponds to similar anomalies found in the other chondrodystrophic breeds of dogs, and it is suggested that the decreased growth of the ulnar bone may be hereditary.