A retrospective study of tumours in black-tailed prairie dogs (Cynomys ludovicianus) submitted to a zoological pathology service.

Fifty-three tumours were diagnosed in samples originating from 167 different black-tailed prairie dogs (Cynomys ludovicianus) submitted to Northwest ZooPath (NZP) between 1996 and 2009. Three prairie dogs had more than one type of neoplasm. Thirty-two of the 50 prairie dogs were from zoological parks in the USA; 17 were owned privately and one was from a wildlife centre. Ages ranged from 2-9 years (median age 5.6 years) for 41 animals in which age was known. Thirty-nine (73.6%) of the tumours were classified as malignant and 14 (26.4%) were benign. Common sites for tumours were the liver, the alimentary tract and the haemolymphoid and integumentary systems. Hepatocellular carcinoma, hepatocellular adenoma, lymphoid malignancies and elodontoma were diagnosed most commonly.