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Vesicular stomatitis virus (VSV) outbreaks periodically occur in livestock in the western US and are thought to originate from outside this country. Feral swine (Sus scrofa) have been identified as an amplifying host for vesicular stomatitis New Jersey virus (VSNJV) and have been used to better understand the epidemiology of this virus through serosurveillance. This study aimed to determine if antibodies to vesicular stomatitis Indiana virus (VSIV) and VSNJV were present in feral swine in the western US and to determine if seropositive animals were associated with areas of previously detected VSV in livestock. A total of 4,541 feral swine samples was tested using virus neutralization (VN); samples exhibiting neutralizing activity against one or more of the viruses were confirmed using competitive ELISA (cELISA). Eight sera exhibited neutralizing activity by VN assay and a single serum sample from an animal from Kinney County, Texas sampled in December 2019 tested positive for antibodies to VSIV by cELISA. This finding is supported by a local outbreak of VSIV in horses in the same county in June 2019. The low prevalence of antibodies against VSNJV and VSIV was unexpected but indicates that feral swine in the western US do not represent an endemic reservoir for either of these viruses. [ABSTRACT FROM AUTHOR]

Wild turkeys (Meleagris gallopavo) are an important game species throughout the geographic range. Populations throughout multiple regions of the US have been declining, including in Kentucky, US, raising concerns among managers and resource users. To better understand the overall population health, we performed postmortem examinations and targeted pathogen, mineral, and toxicant testing on 36 adult male, apparently healthy, wild turkeys that were hunter harvested in western Kentucky during April 2018. We found that birds were in fair to good nutritional condition with no significant gross or microscopic lesions. Ticks (Amblyomma spp.) and lice (three species) were present on 94 and 31% of birds, respectively. We commonly detected intestinal nematodes and cestodes and found coccidian oocysts in 39% and capillarid eggs in 6% of birds. The prevalences of lymphoproliferative disease virus and reticuloendotheliosis virus were 39 and 11%, respectively. Spleen samples tested with PCR were positive for Borrelia burgdorferi, Haemoproteus sp., and Leucocytozoon sp. in 11, 83, and 3%, respectively. Based on a subjective histologic assessment of testis tissues, most birds had widespread and abundant sperm present. Mineral analysis and broad toxicant screening on liver samples from 32 turkeys were unremarkable. Further work is needed to assess potential population risk factors and to determine individual- and population-level impacts of pathogens on adults and poults. [ABSTRACT FROM AUTHOR]

Over the last four decades, Barred Owls (Strix varia) have expanded their range to include much of western North America, including California. This expansion is suspected to have contributed to declining populations of a closely related species, the federally threatened Northern Spotted Owl (Strix occidentalis caurina). As a result, understanding potential health threats to Barred Owls has implications for Spotted Owl health and recovery. From 2016 to 2020, 69 Barred Owls were collected to determine the apparent prevalence of periorbital nematode infection, to identify the parasite species present, and to investigate the potential pathologic effects on their hosts. The nematodes were morphologically identified as Oxyspirura and Aprocta spp. On the basis of phylogenetic analyses, they were clearly divergent from published sequences of other species within these genera. Overall, 34 (49%) Barred Owls were infected with periorbital nematodes, with Oxyspirura sp. infections being much more common (94%) than Aprocta sp. (18%). Histopathology revealed varying severity of conjunctivitis in infected owls. Despite the frequency of infection and subsequent inflammation, parasite burden was not associated with reduced body weight in these owls. As a result, the potential health effect of these nematodes is unclear. Further taxonomic characterization is needed to determine potential novelty of these nematodes. [ABSTRACT FROM AUTHOR]