Adenoviral hemorrhagic disease in a farmed elk (Cervus canadensis) in Alberta, Canada.

Adenoviral hemorrhagic disease (AHD), caused by deer atadenovirus A (OdAdV-1), affects captive and free-ranging cervids across North America. Here we present a case of AHD in a 6-month-old female elk calf from a farm in Alberta. Histopathology revealed multisystemic vasculitis with endothelial intranuclear inclusion bodies, pulmonary hemorrhage, and small intestinal hemorrhage characteristic of the acute systemic form of AHD. Immunohistochemistry was positive for OdAdV-1, confirming the diagnosis. Whole-genome sequencing of the virus was conducted for phylogenetic comparison. This is the 1st reported case of AHD in a farmed elk in Canada and the 1st reported case in an elk in Alberta. Key clinical message: Adenoviral hemorrhagic disease (AHD) is an emerging disease that should be investigated as a top differential when diagnosticians and veterinarians encounter young cervids found dead with pulmonary edema or hemorrhage and/or hemorrhagic enteropathy.

Maladie hémorragique adénovirale chez un wapiti d'élevage (Cervus canadensis) en Alberta, Canada. La maladie hémorragique adénovirale (AHD), causée par l'atadénovirus A du cerf (OdAdV-1), affecte les cervidés en captivité et en liberté partout en Amérique du Nord. Nous présentons ici un cas d'AHD chez un wapiti femelle de 6 mois d'une ferme en Alberta. L'histopathologie a révélé une vascularite multi-systémique avec des corps d'inclusion intranucléaires endothéliaux, une hémorragie pulmonaire et une hémorragie de l'intestin grêle caractéristiques de la forme systémique aiguë de l'AHD. L'immunohistochimie était positive pour OdAdV-1, confirmant le diagnostic. Le séquençage du génome entier du virus a été réalisé à des fins de comparaison phylogénétique. Il s'agit du premier cas signalé d'AHD chez un wapiti d'élevage au Canada et du premier cas signalé chez un wapiti en Alberta.Message clinique clé :La maladie hémorragique adénovirale (AHD) est une maladie émergente qui devrait être investiguée comme un diagnostic différentiel important lorsque les diagnosticiens et les vétérinaires rencontrent de jeunes cervidés trouvés morts avec un œdème pulmonaire ou une hémorragie et/ou une entéropathie hémorragique.(Traduit par Dr Serge Messier).

Chronic interstitial pneumonia with features of organizing pneumonia in an adult horse.

A 22-y-old American Quarter Horse gelding was presented with a history of chronic progressive respiratory problems and a diffuse pulmonary nodular pattern in thoracic radiographs. The horse was euthanized, and 4 formalin-fixed samples of lung were submitted for histopathology. There were multifocal areas of marked thickening of alveolar septa as a result of proliferation of myofibroblasts embedded in fibromyxoid matrix (interpreted as "Masson bodies"), focal areas of fibrosis, and numerous papillary projections of connective tissue into bronchioles. A diagnosis of organizing pneumonia was reached. No etiology was found for this lesion. It is important to consider causes of chronic interstitial pneumonia with fibrosis in horses other than equid herpesvirus 5, such as complicated viral or bacterial pneumonia or chronic toxicoses.

Clostridium sordellii-associated gas gangrene in 8 horses, 1998-2019.

Gas gangrene occurs in several animal species and is caused by one or more clostridial species. In horses, the disease is most often caused by Clostridium perfringens type A. Although Clostridium sordellii has been associated with gas gangrene in ruminants and humans, cases of the disease associated with this microorganism have not been described in horses, to our knowledge. We report herein 8 cases of gas gangrene caused by C. sordellii in horses. These cases were characterized by myonecrosis and cellulitis, associated with systemic changes suggestive of toxic shock. The diagnosis was confirmed by gross and microscopic changes combined with anaerobic culture, fluorescent antibody test, immunohistochemistry, and/or PCR. The predisposing factor in these cases was an injection or a traumatic skin injury. C. sordellii should be considered as a possible etiologic agent in cases of gas gangrene in horses.

Resistance of colostrum-deprived domestic lambs to infection with deer adenovirus.

Seven colostrum-deprived, 3-4-wk-old Rambouillet-Hampshire lambs were inoculated via the mucous membranes with deer adenovirus (DAdV) and monitored for clinical signs for 21 d post-inoculation at which time animals were euthanized and postmortem examinations were performed. Pre-inoculation and post-inoculation serum samples were tested for antibodies to DAdV, ovine adenovirus 7, bovine adenovirus 7, and goat adenovirus 1. Evidence for DAdV infection was determined by virus isolation, PCR tests, and histopathology with immunohistochemistry tests for DAdV. No clinical signs or lesions consistent with adenoviral hemorrhagic disease (AHD) in deer were seen in the lambs, and the lambs did not seroconvert to DAdV. DAdV was not detected by PCR, virus isolation, or immunohistochemistry in any of the samples tested from the lambs. A positive control deer similarly inoculated with DAdV developed fatal AHD 1 wk post-inoculation. Our colostrum-deprived lambs did not become infected when inoculated with DAdV.

Adenoviral hemorrhagic disease in California mule deer, 1990-2014.

We reviewed case records from the California Animal Health and Food Safety (CAHFS) laboratory and the California Department of Fish and Wildlife (CDFW) spanning 25 years (1990-2014) for all deer accessions submitted to CAHFS for pathology and/or histopathology, with and without a diagnosis of adenoviral hemorrhagic disease (AHD), in order to determine the prevalence of AHD in California. We also examined spatial and temporal distribution, age, and mule deer subspecies in deer that died from AHD. Of 483 deer submitted to CAHFS for diagnostic testing in 1990-2014, 17.2% were diagnosed with confirmed AHD, and 26.5% were confirmed plus suspected cases of AHD. Columbian black-tailed deer ( Odocoileus hemionus columbianus), particularly fawns and juveniles, were most frequently affected. Deer adenovirus ( Odocoileus adenovirus 1; OdAdV-1) was detected by immunohistochemistry in archived CDFW formalin-fixed, paraffin-embedded tissues from deer that died in mortality events in 1981, 1983, and 1986-1987. OdAdV-1 is a common cause of hemorrhagic disease mortality events in California deer, and mortality as a result of AHD is documented as early as 1981.

Detection of bluetongue virus in Brazilian cervids in São Paulo state / Detecção de vírus da língua azul em cervídeos brasileiros no estado de São Paulo

Viral hemorrhagic diseases in cervids occur worldwide and include epizootic hemorrhagic disease (EHD), bluetongue (BT), and adenoviral hemorrhagic disease (AHD). Since gross lesions in all three hemorrhagic diseases are identical (hemorrhagic enteropathy, pulmonary edema, systemic petechial and suffusion hemorrhages), it is necessary to use accurate techniques for a definitive etiologic diagnosis. Archival material (paraffin blocks) at the Department of Veterinary Pathology of FCAV - Unesp was reviewed for lesions of hemorrhagic disease and 42 captive and free-living Brazilian deer were selected to include in this study. Paraffin-embedded tissues were evaluated using immunohistochemistry and tested negative for adenovirus. Using real time RT-PCR, EHD virus was not detected in paraffin-embedded tissues in any of the cases evaluated. The same technique was used for detection of BT virus and seven positive animals (16,66%) were confirmed after agarose 4% gel electrophoresis and gene sequencing. The main macroscopic changes observed in the positive animals were hemorrhagic intestinal contents, reddish mucous membrane of the gastrointestinal tract, ulcers on tongue and petechiae in various organs. Microscopic changes observed were lymphocytic inflammatory infiltrate in liver, kidney and lungs, hemorrhage, and congestion in various organs. All positive cases were from captive animals, three females (two young and one adult), and four young males. This study demonstrates that the bluetongue virus is involved in hemorrhagic disease outbreaks of deer in Brazil.(AU)

Doenças hemorrágicas virais em cervídeos ocorrem no mundo todo e incluem a doença epizoótica hemorrágica (DEH), língua azul (LA), e doença hemorrágica por adenovírus (DHA). Uma vez que as lesões nas três doenças hemorrágicas são idênticas (enteropatia hemorrágica, edema pulmonar, petéquias sistêmicas e sufusões hemorrágicas), é necessário utilizar técnicas precisas para um diagnóstico etiológico definitivo. Material de arquivo (blocos de parafina) do Departamento de Patologia Veterinária da FCAV - Unesp foi revisado para lesões de doenças hemorrágicas e 42 cervídeos brasileiros de cativeiro e de vida livre foram selecionados e incluídos neste estudo. Tecidos embebidos em parafina foram avaliados usando imunohistoquímica e foram negativos para adenovírus. Usando o RT-PCR em tempo real, o vírus da DEH não foi detectado nos tecidos de nenhum dos casos avaliados. A mesma técnica foi utilizada para detecção do vírus da LA e sete animais positivos (16,66%) foram confirmados após eletroforese em gel de agarose a 4% e sequenciamento genético. As principais alterações macroscópicas observadas nos animais positivos foram conteúdo intestinal hemorrágico, mucosa do trato gastrointestinal avermelhada, úlceras na língua e petéquias em vários órgãos. As alterações microscópicas observadas foram infiltrado inflamatório linfocítico em fígado, rins e pulmões, e hemorragia e congestão em vários órgãos. Todos os casos positivos foram de animais de cativeiro, três fêmeas (dois jovens e um adulto), e quatro jovens do sexo masculino. Este estudo demonstra que o vírus da lingual azul está envolvido nos surtos de doença hemorrágica em veados no Brasil.(AU)

Whole-genome sequences of Odocoileus hemionus deer adenovirus isolates from deer, moose and elk are highly conserved and support a new species in the genus Atadenovirus.

We present the first complete genome sequence of Odocoileus hemionus deer adenovirus 1 (OdAdV-1). This virus can cause sporadic haemorrhagic disease in cervids, although epizootics with high mortality have occurred in California. OdAdV-1 has been placed in the genus Atadenovirus, based on partial hexon, pVIII and fibre genes. Ten field isolates recovered from naturally infected mule deer (Odocoileus hemionus), white-tailed deer (Odocoileus virginiana) and moose (Alces alces) from Wyoming, black-tailed deer (Odocoileus hemionus columbianus) from California, and Rocky Mountain elk (Cervus elaphus nelsoni) from Colorado and Washington state were sequenced. The genome lengths ranged from 30 620 to 30 699 bp, contained the predicted proteins and gene organization typical of members of genus Atadenovirus, and had a high percentage of A/T nucleotides (66.7 %). Phylogenic analysis found that the closest ancestry was with ruminant atadenoviruses, while a divergence of the hexon, polymerase and penton base proteins of more than 15 % supports classification as a new species. Genetic global comparison between the 10 isolates found an overall 99 % identity, but greater divergence was found between those recovered from moose and elk as compared to deer, and a single variable region contained most of these differences. Our findings demonstrate that OdAdV-1 is highly conserved between 10 isolates recovered from multiple related cervid species, but genotypic differences, largely localized to a variable region, define two strains. We propose that the virus type name be changed to cervid adenovirus 1, with the species name Cervid atadenovirus A. Sequence data were used to develop molecular assays for improved detection and genotyping.

Production of a recombinant capsid protein VP1 from a newly described polyomavirus (RacPyV) for downstream use in virus characterization.

Here we describe the methods for production of a recombinant viral capsid protein and subsequent use in an indirect enzyme linked immunosorbent assay (ELISA), and for use in production of a rabbit polyclonal antibody. These reagents were utilized in development and optimization of an ELISA, which established the extent of exposure of free ranging raccoons to a newly described polyomavirus (RacPyV) [1]. Production of a polyclonal antibody has allowed for further characterization of RacPyV, including immunohistochemistry and immunocytochemistry techniques, in order to answer questions about pathogenesis of this virus.

Isolation of a Bohle-like iridovirus from boreal toads housed within a cosmopolitan aquarium collection.

A captive 'survival assurance' population of 56 endangered boreal toads Anaxyrus boreas boreas, housed within a cosmopolitan collection of amphibians originating from Southeast Asia and other locations, experienced high mortality (91%) in April to July 2010. Histological examination demonstrated lesions consistent with ranaviral disease, including multicentric necrosis of skin, kidney, liver, spleen, and hematopoietic tissue, vasculitis, and myriad basophilic intracytoplasmic inclusion bodies. Initial confirmation of ranavirus infection was made by Taqman real-time PCR analysis of a portion of the major capsid protein (MCP) gene and detection of iridovirus-like particles by transmission electron microscopy. Preliminary DNA sequence analysis of the MCP, DNA polymerase, and neurofilament protein (NFP) genes demonstrated highest identity with Bohle iridovirus (BIV). A virus, tentatively designated zoo ranavirus (ZRV), was subsequently isolated, and viral protein profiles, restriction fragment length polymorphism analysis, and next generation DNA sequencing were performed. Comparison of a concatenated set of 4 ZRV genes, for which BIV sequence data are available, with sequence data from representative ranaviruses confirmed that ZRV was most similar to BIV. This is the first report of a BIV-like agent outside of Australia. However, it is not clear whether ZRV is a novel North American variant of BIV or whether it was acquired by exposure to amphibians co-inhabiting the same facility and originating from different geographic locations. Lastly, several surviving toads remained PCR-positive 10 wk after the conclusion of the outbreak. This finding has implications for the management of amphibians destined for use in reintroduction programs, as their release may inadvertently lead to viral dissemination.

Novel polyomavirus associated with brain tumors in free-ranging raccoons, western United States.

Tumors of any type are exceedingly rare in raccoons. High-grade brain tumors, consistently located in the frontal lobes and olfactory tracts, were detected in 10 raccoons during March 2010-May 2012 in California and Oregon, suggesting an emerging, infectious origin. We have identified a candidate etiologic agent, dubbed raccoon polyomavirus, that was present in the tumor tissue of all affected animals but not in tissues from 20 unaffected animals. Southern blot hybridization and rolling circle amplification showed the episomal viral genome in the tumors. The multifunctional nuclear protein large T-antigen was detectable by immunohistochemical analyses in a subset of neoplastic cells. Raccoon polyomavirus may contribute to the development of malignant brain tumors of raccoons.

Evaluation of the pathogenic potential of cervid adenovirus in calves.

Four 3-month-old Jersey calves and three 3-month-old Holstein calves were inoculated with cervid adenovirus and monitored for clinical signs until necropsied between 10 and 42 days postinoculation. The neonatal Jersey calves had received colostrum, and the Holstein calves were colostrum deprived. Preinoculation and postinoculation serum samples were tested for antibodies to the cervid adenovirus, bovine adenovirus type 6, bovine adenovirus type 7, and goat adenovirus type 1. Virus isolation was performed on kidney, nasal secretion, and/or lung homogenates in fetal white-tailed deer lung cells. Negatively stained preparations of feces from Jersey calves were examined weekly using an electron microscope, and weekly blood samples were collected for complete blood counts. Full necropsies were performed on all calves. A complete selection of tissues was evaluated for microscopic changes, and immunohistochemistry was performed on all tissues using a polyclonal antibody to deer adenovirus. No clinical signs were observed in the calves during the study period. Following inoculation, colostrum-deprived calves developed low antibody titers to deer adenovirus, while the Jersey calves that received colostrum did not. Calves that received colostrum had high antibody titers to bovine adenovirus type 7 and goat adenovirus type 1. No consistent gross or microscopic lesions were seen. Adenovirus was not observed in negatively stained preparations of feces. Immunohistochemistry results did not demonstrate virus in all tissues examined microscopically, and virus was not isolated from lungs, nasal secretions, and kidneys.

Adult cockatiels (Nymphicus hollandicus) at maintenance are more sensitive to diets containing excess vitamin A than to vitamin A-deficient diets.

The purpose of this experiment was to examine the physiological responses of adult cockatiels at maintenance to dietary vitamin A (VA) concentrations, and to identify concentrations associated with deficiency and toxicity. Adult cockatiels at maintenance (n = 22, 2-3 y of age) were fed a diet of 0, 600, 3000 or 30,000 microg VA/kg (0, 2000, 10,000 or 100,000 IU), and monitored for signs of VA deficiency or toxicity for up to 706 d. The analyzed diet concentrations were 0, 835, 2815 and 24,549 microg/kg, respectively. After 269 d, birds fed the 30,000 microg/kg VA diet had greater plasma retinal concentrations, markedly intensified vocalization patterns, pancreatitis and multifocal accumulation of lymphocytes in the lamina propria of the duodenum compared to birds fed the 600 microg/kg diet (P < 0.05). The 3000 microg/kg VA diet induced increased plasma retinol, splenic hemosiderosis and altered vocalization patterns (P < 0.05), although not as striking as those induced by the 30,000 microg/kg VA diet. The secondary antibody response was reduced after 225 d and vocalization patterns were altered in birds fed 0 microg/kg VA (P < 0.05), but after almost 2 y there were no changes in body condition, plasma retinol, organ pathology or classical signs of deficiency such as squamous metaplasia of nasal epithelia. Thus, adult cockatiels at maintenance were more susceptible to VA toxicity than to VA deficiency and concentrations > or = 3000 microg VA/kg diet can cause toxicity. It is possible that disturbances in VA nutrition contribute to the widespread incidence of behavioral problems reported in companion birds.

An avian bioassay for environmental estrogens: the growth response of zebra finch (Taeniopygia guttata) chick oviduct to oral estrogens.

The rat uterotrophic assay is a recommended tier 1 screening assay for environmental estrogens, but no comparable assay exists for altricial birds. We orally dosed zebra finch chicks daily during their linear growth phase (days 5-11) with estradiol benzoate (EB), genistein, methoxychlor, or octylphenol, all dissolved or suspended in canola oil, or canola oil alone, as a vehicle control. On day 12, oviducts were removed, weighed and examined histologically. All doses of EB (0.1-1,000 nmol/g body wt), genistein at 100 nmol/g. and methoxychlor and octylphenol at 1,000 nmol/g, markedly increased oviduct weight, with the highest dose of EB inducing a 60-fold increase over controls. Oviducts were differentiated in a dose-depedent manner to the point of having tubular glands and a pseudostratified, ciliated epithelium at the higher doses of EB. Our earlier results show that EB at 100 and 1,000 nmol/g impairs reproductive performance of zebra finches. Thus, the zebra finch oviduct bioassay measures estrogenicity over a wide dose range and, for EB exposure, can predict impairment in adult reproductive performance. The responsiveness of chick oviducts to estrogen stimulation may serve as a useful marker of estrogen exposure in wild populations of songbirds.

Adenoviral infection in captive moose (Alces alces) in Canada.

Adenoviral infection was associated with hemorrhagic enteritis, serosal hemorrhages, and severe pulmonary edema in six captive moose (Alces alces) in Toronto, Ontario, Canada: an adult female moose and three calves in 1985 and two calves in 1998. Adenoviral disease was suspected based on histological findings of systemic vasculitis and widespread thrombosis associated with amphophilic intranuclear inclusions in endothelial cells. Diagnosis was confirmed by immunohistochemistry using antiserum to bovine adenovirus type 5, transmission electron microscopic identification of viral particles consistent in morphology with adenovirus within nuclei of pulmonary endothelial cells in an affected calf, and virus isolation. The restriction pattern of virus isolated from the lung of one of the calves indicated that the virus was identical to a recently characterized adenovirus in black-tailed deer (Odocoileus hemionus) in California. The moose adenovirus reported here may have been endemic in the captive moose herd, or infection may have resulted from either direct or indirect contact with other species of captive or wild cervids. This is the first report of adenoviral infection in moose and of the presence of adenoviral disease in a cervid in Canada.