Histopathologic study of long-bone growth plates confirms the basset hound as an osteochondrodysplastic breed.

Osteochondrodysplasias are caused by abnormal development and growth of cartilage and bone. These abnormalities have been reported in both humans and animals with dwarfism. The basset hound is considered a breed with a disproportionate prevalence of dwarfism, the cause of which is unknown. To determine the type of osteochondrodysplasia in this breed, we analyzed histologically the growth plates from the long bones of a basset hound and a Doberman pinscher, both 2 mo old. Tissue was fixed in 4% paraformaldehyde, embedded in paraffin, sectioned at 5 microm, stained with hematoxylin and eosin, and analyzed by light microscopy. Our results suggest that by this method the basset hound can be defined only as a breed having osteochondrodysplasia due to a primary cartilage problem in the growth plate.