Seventeen counties in northern California experienced epizootics of high mortality in the mule deer (Odocoileus hemionus) population during the latter half of 1993. Thirteen deer submitted to the California Veterinary Diagnostic Laboratory System as part of this natural die-off had systemic adenovirus infection. Pulmonary edema was present in all 13 deer. Erosions, ulceration, and abscessation of the upper alimentary tract occurred in 7/13 deer. Four of 13 deer had hemorrhagic enteritis. All 13 deer had widespread systemic vasculitis with endothelial intranuclear inclusions. Fluorescein isothiocyanate-labeled antibody directed against bovine adenovirus type 5 bound to antigen in endothelial cells. Adenovirus was identified by transmission electron microscopy within the nuclei of endothelial cells in 6/6 deer examined. An adenovirus was isolated from lung homogenates of one deer that were cultured on black-tailed deer pulmonary artery endothelial cells. With the exception of the intranuclear inclusions evident on histologic evaluation, gross and histologic changes were similar to those described for bluetongue virus infection and epizootic hemorrhagic disease virus infection in white-tailed deer. Nine additional deer were emaciated and had pharyngeal abscesses with focal vasculitis, which may represent the chronic affects of previous nonfatal adenovirus infection.

No abstract

Abstract. Adenovirus infection was the cause of an epizootic of hemorrhagic disease that is believed to have killed thousands of mule deer (Odocoileus hemionus) in California during the latter half of 1993. A systemic vasculitis with pulmonary edema and hemorrhagic enteropathy or a localized vasculitis associated with necrotizing stomatitis/pharyngitis/glossitis or osteomyelitis of the jaw were common necropsy findings in animals that died during this epizootic. To study transmission of adenovirus infection in deer and susceptibility of black-tailed deer (Odocoileus hemionus columbianus) fawns to adenovirus infection, six 3-6-month-old black-tailed fawns were divided into two treatment groups. One group was inoculated intravenously and the other group was inoculated through the mucous membranes of the eyes, nose and mouth with purified adenovirus. Each treatment group also included two additional fawns (four total) that were not inoculated but were exposed to inoculated animals (contact animals). One fawn served as a negative control. Between 4 and 16 days postinoculation, 8/10 fawns developed systemic or localized infection with lesions identical to lesions seen in animals with natural disease that died during the epizootic. Transmission was by direct contact, and the route of inoculation did not affect the incubation period or the distribution of the virus (systemic or the localized infection). Immunohistochemical analysis using polyclonal antiserum against bovine adenovirus type 5 demonstrated staining in endothelial cells of vessels in numerous tissues in animals with systemic infection and endothelial staining only in vessels subtending necrotic foci in the upper alimentary tract in animals with the localized form of the disease. All inoculated or exposed animals had staining in the tonsillar epithelium. Transmission electron microscopic examination of lung and ileum from two fawns with pulmonary edema and hemorrhagic enteropathy demonstrated endothelial necrosis and adenovirus virions in endothelial cell nuclei. Adenovirus was reisolated in black-tailed deer pulmonary artery endothelial cells using lung homogenate of the first fawn that developed systemic adenovirus infection. Serum virus neutralization test results suggest that this deer adenovirus is a new serotype.Key words: Adenovirus; deer; experimental infection; hemorrhagic disease; immunohistochemistry; Odocoileus hemionus columbianus; pathology; stomatitis; transmission.We previously described an epizootic of hemorrhagic disease in California black-tailed deer (Odocoileus hemionus columbianus) that was associated with infection by a newly recognized adenovirus. 28 Two forms of the disease, a systemic and a localized form, were described. Necropsy findings in deer that died of systemic adenovirus infection were similar to lesions described in animals infected with bluetongue (BT) virus or epizootic hemorrhagic disease (EHD) virus, 10,11,14,15 and included pulmonary edema and less often hemorrhagic enteropathy. Panvasculitis with endothelial intranu...

Free-ranging mule deer (MD; Odocoileus hemionus) from Arizona and California were tested for evidence of infection with several tick-borne pathogens, including species of Ehrlichia, Anaplasma, Babesia, and Borrelia. Of 125 mule deer tested from Arizona, 29 (23%) and 11 (9%) had antibodies reactive to E. chaffeensis and A. phagocytophilum by indirect immunofluorescent antibody testing, respectively; none of the six MD tested from California were seropositive. Using a commercial competitive ELISA kit, antibodies reactive to Anaplasma spp. were detected in 19 (15%) MD from Arizona and four of six (67%) MD from California. Polymerase chain reaction (PCR) testing for tick-borne pathogens was conducted on blood samples from 29 MD from Arizona and 11 MD from California. Twenty-two of 29 (75.9%) MD from Arizona had PCR evidence of infection with at least one tick-borne pathogen. We detected an Anaplasma sp. in 19 of 29 (65.5%) MD and a Babesia sp. in 10 of 29 (34%) MD. Sequencing of these amplicons indicated that the Anaplasma sp. was the same that had previously been detected in MD from California and the Babesia sp. was similar to one previously detected in a reindeer (Rangifer tarandus tarandus) from California. All of the California MD had evidence of infection with a tick-borne pathogen. Two different species of Anaplasma spp. were detected in MD from California, eight of of 11 MD were infected with an Anaplasma sp., and three of 11 MD were infected with A. ovis. This is the first report of a mule deer naturally infected with A. ovis. Ten of 11 MD from California were infected with a Babesia-like organism previously associated with human disease, and a single MD was PCR positive for Borrelia coriaceae, which has been associated with epizootic bovine abortion. Together, these data suggest that MD in northern Arizona and eastern California are exposed to several pathogens of human and veterinary importance.

No abstract