Spontaneous Hepatobiliary Disease in a Breeding Colony of Aotus spp.

ABSTRACT Background Owl monkeys are nonhuman primate species in the genus Aotus . The Michale E. Keeling Center for Comparative Medicine and Research maintains an Owl Monkey Breeding and Research Resource composed of four species of owl monkeys: Aotus nancymai , A. vociferans , A. azarae , and A. griseimembra . Disease of the hepatobiliary system has not been well characterized in Aotus. Methods Necropsy records from a 17‐year period were reviewed to characterize the gross and microscopic lesions of liver disease. Results 316 adult owl monkeys were submitted for necropsy in the review period; 22 of 316 (6.96%) were diagnosed with hepatobiliary disease. Cardiac‐associated hepatopathy was the most common diagnosis (6/22). Previously unreported conditions included cystic mucinous hyperplasia (1/22), acute cholangiohepatitis (1/22), idiopathic end‐stage hepatopathy (1/22), cholangiocarcinoma (2/22), and acute cholecystitis (4/22). Vitamin E deficiency anemia (3/22) and hemosiderosis (4/22) have been reported in the genus, and these diagnoses were noted. Conclusions The spectrum of hepatobiliary pathology in owl monkeys is broader than previous reports have suggested.