Parelaphostrongylus tenuis in captive reindeer and sable antelope

Parelaphostrongylus tenuis caused neurologic disease in 6 reindeer (Rangifer tarandus tarandus) and 2 sable antelope (Hippotragus niger) that were housed at the National Zoological Park Conservation and Research Center in Front Royal, Va. Progressive hindlimb ataxia and weakness were seen in all affected animals. The parasite was recovered from the subdural space of one reindeer and was seen histologically within the neuropil of another reindeer and a sable antelope. In the other reindeer and sable antelope, diagnoses of parelaphostrongylosis were based on clinicoepidemiologic findings and microscopic lesions. Because parelaphostrongylosis is a density-dependent disease and because the number of white-tailed deer probably will increase, the incidence of P tenuis infections in domestic and nondomestic animals probably will increase as well. Zoos and wildlife parks especially should be cautious when introducing exotic hoofstock to areas with Parelaphostrongylus tenuis-infected white-tailed deer.