Development of a serum plate agglutination test to detect antibodies to Ornithobacterium rhinotracheale.

Abstract

sistent with Elaeophora, a diagnosis of elaeophorosis, probably caused by E. schneideri, was made. Blindness, circling, and ataxia as seen in this moose are characteristic clinical signs of infection with E. schneideri in moose from Montana5 and Colorado.4 Histopathologic findings in moose elaeophorosis are similar to those of elk (Cervus elaphus)5 and include regions of cerebrocortical necrosis, intimal proliferation within leptomeningeal arteries, and thrombosis of cerebral vessels. The vasculitis reported in this moose has been described in elk with elaeophorosis.1 Both previous reports of elaeophorosis in moose contained descriptions of nematodes within histologic sections of brain, and nematodes were recovered from the carotid arteries.4,5 Despite examination of numerous brain sections and other tissues, only the nematode within an artery surrounding a mesenteric lymph node was observed; the carotid arteries were not examined grossly. The observation of the larval nematode within a mesenteric vessel is not surprising based on observations in elk with elaeophorosis in which parasites were observed within multiple organ systems. Postmortem migration of nematodes was also thought to occur.1 The cause of the observed eosinophilic dermatitis was not determined and although a localized reaction to circulating Elaeophora microfilariae was considered, no microfilariae were observed on histologic examination. This is the first report of elaeophorosis in a moose from Washington state and the first description of this parasite from the eastern portion of the state. The only previous report of elaeophorosis reported from Washington state was E. schneideri from a black-tailed deer (Odocoileus hemionus columbianus) from the western portion of the state.2 Although E. schneideri is considered rare in Washington,2 moose may be a sensitive indicator species for the presence of the parasite, especially in areas where the parasite has not been diagnosed previously. Acknowledgements. We thank Dr. Melinda Wilkerson, Washington Animal Disease Diagnostic Laboratory, for assistance with histopathology, Dr. Scott Lyell Gardner, University of Nebraska State Museum, for assistance in examination of the parasite, and Steve Judd, the Colville Indian Tribe, for bringing this moose to our attention.