Survey of Post-Cranial Skeletal Pathology in Snakes

Previous reports on skeletal pathology in captive snakes did not clarify the relationship of lesions to captive or free-ranging status. In this study, post-cranial skeletons from 7,950 captive and free-ranging snakes in nine of the major North American collections were examined macroscopically, microscopically and radiologically for the presence of pathology. Micro-computerized tomography was performed on two skeletons on which surface microscopy failed to provide a definitive diagnosis. Osteomyelitis was identified in the vertebrae of 24 snakes and spondyloarthropathy in one snake. Neoplasia or congenital anomalies were not found. Osteomyelitis was four times as common in Viperidae than in Colubridae and twice as common as in Boidae, independent of captive or free-ranging status. A lytic lesion in the vertebrae of one snake was suggestive of fungal disease. The progression of bone lesions was greater in captive snakes, but the prevalence was independent of captive or free-ranging status. The results of this study indicate that bone alterations, previously proposed as neoplastic disease, in archival snake skeletons were most likely of infectious aetiology, and establish macroscopic examination as a useful technique for characterizing skeletal pathology in snakes.