Gongylonema sp. are spirurid parasites that infect the upper digestive and respiratory tracts of a variety of mammals and birds. In most mammals, gongylonemiasis is considered an incidental finding, associated with few clinical signs and minimal pathologic changes.1,5 There have been multiple reports of the parasite infecting a wide range of primate species.2-6 Recent reports of lingual gongylonemiasis (G. pulchrum) in Goeldi’s monkeys (Callimico goeldii) and common marmosets (Callithrix jacchus) are the first cases to describe pathologic changes associated with infection in neotropical New World primates.2 4 In these cases, pruritis of the perioral tissues, inflammation of the tongue and lips, and chronic ptyalism were the primary clinical signs.
Numerous Gongylonema sp. infections with associated pathologic lesions and clinical signs have been identified in Goeldi’s monkeys at Brookfield Zoo over the course of several years. An increase in the incidence of clinical signs in Goeldi’s monkeys, as well as other callitrichid species, prompted a study to attempt to determine the prevalence of infection within the collection and evaluate treatment and control protocols.
There have been no studies that we are aware of specifically investigating the treatment of Gongylonema sp. in callitrichids. Treatment with a variety of antihelmintics in these species has been primarily empirical.4,6 The lack of definitive information about the prepatent period of Gongylonema sp. in primates, the efficacy of anthelmintic drugs, appropriate dosages, and length of treatment have made control of this parasite challenging. Diligent insect control and routine prophylactic deworming have been suggested as the primary method to control infections within a collection.4,6
Twenty-one callitrichids, representing four species, housed in the same room, were included in this study. Repeated cytologic evaluations of scrapings taken from the mucosa of the tongue were performed to determine if individual animals were infected with parasite. The callitrichids were divided into two random groups and received treatment with either ivermectin or mebendazole. Numerous animals displayed clinical signs throughout the study; however, Gongylonema sp. infections were only confirmed by tongue scrapings in two animals. Although the low number of positive tongue scrapings precluded comparative statistical evaluation of the efficacy of the anthelmintic treatment protocols, clinical signs consistent with Gongylonema sp. and the number of confirmed cases have decreased since the treatment study.
We would like to thank Dr. Jackie Zdziarski, the animal hospital keepers, and laboratory staff at Brookfield Zoo for their help collecting and reading the tongue scrapings. We also appreciate the assistance from the animal management and keeper staff at Tropic World, James Baier from McCloud Pest Control, and the students at the University of Illinois, College of Veterinary Medicine who helped make this project possible.
1. Bowman, D.D. 1999. In: Georgis’ Parasitology for Veterinarians, 7th ed. W. B. Saunders Co., Philadelphia, Pennsylvania. Pp. 204–205.
2. Brack, M. 1996. Gongylonematiasis in the common marmoset (Callithrix jacchus). Lab. Anim. Sci. 46:266–270.
3. Craig, L.E., J.M. Kinsella, L.J. Lodwick, M.R. Cranfield, and J.D. Strandberg. 1998. Gongylonema macrogubernaculum in captive African squirrels (Funisciurus substriatus and Xerus erythropus) and lion-tailed macaques (Macaca silenus). J. Zoo. Wildl. Med. 29:331–337.
4. Duncan, M., L. Tell, C.H. Gardiner, and R.J. Montali. 1995. Lingual gongylonemiasis and pasteurellosis in Goeldi's monkeys (Callimico goeldii). J. Zoo. Wildl. Med. 26:102–108.
5. Flynn, R.J. 1973. Parasitology of Laboratory Animals. Iowa State University Press, Ames, IA. Pp. 286–287.
6. Montali, R.J., and M. Bush. 1999. Diseases of Callitrichidae. In: Fowler, M.E., and R.E. Miller (eds.). Zoo and Wild Animal Medicine. 4th ed. W.B. Saunders Co., Philadelphia, Pennsylvania. Pp. 372–373.