A Retrospective Study of Neoplasia in a Collection of Captive Snakes

A retrospective study of neoplasia in a collection of snakes was conducted due to the large number of neoplasms observed in 1991. Individual snake necropsies, medical records, and inventory records at the Sacramento Zoo were reviewed for the period 1 July 1981-30 June 1991. Twenty-nine neoplasms were diagnosed in 20 individual snakes. Nineteen neoplasms were of epithelial origin, and 10 were of mesenchymal origin. Twenty-two (76%) neoplasms were considered malignant, and five neoplasms had metastases. Seven of 10 mesenchymal neoplasms were poorly differentiated spindle cell sarcomas. Five snakes had multiple types of neoplasms. Thirteen neoplasms were detected clinically and diagnosed antemortem. The annual rate of neoplasia for the population ranged from 0% to 14.1% and increased dramatically from 1988 to 1991. No specific type of neoplasm was more prevalent during this increase. The annual rate of neoplasia at necropsy ranged from 0% to 70% and was 23.1% for the 10-yr study period.