Hydatid echinococcosis (Echinococcus granulosus) in a laboratory colony ofpig-tailed macaques (Macaca nemestrina)

Several cases of hydatid echinococcosis were diagnosed in a laboratory colo ny of 19 pig-tailed macaques (Macaca nemestrina) at the Paul Ehrlich Instit ute, Germany. Three hydatid cysts were found in the liver of an euthanized animal. The diagnosis of an Echinococcus granulosus infection was confirmed by histopathology and the results of a specific polymerase chain reaction. The serum of five of 14 other monkeys tested for Echinococcus antibodies u sing a genus-specific enzyme-linked immunosorbent assay (ELISA) was positiv e or weakly positive; none of the animals, however, showed specific reactio ns in an E. multilocularis-specific ELISA. On ultrasonographic examination, alterations in the liver were found in four of the serologically positive monkeys, and two animals showed clinical signs such as progressive anorexia , apathy and icterus. The monkeys had most probably acquired the E. granulo sus infection in their breeding colony in Slovenia.