Journal of Wildlife Diseases最新文献

Emydomyces testavorans: is an onygenalean fungus associated with shell and skin lesions in chelonians and is increasingly linked to morbidity and mortality. Effective disinfection methods are a critical component of biosecurity protocols to prevent and manage emydomycosis; however, disinfectant efficacy against E. testavorans is unknown. This study determined the in vitro efficacy of 13 disinfectants across a range of concentrations and exposure times used in veterinary, wildlife, and environmental settings against E. testavorans. Pure E. testavorans culture material was exposed to each disinfectant at manufacturer-recommended concentration and exposure times in triplicate. Disinfectant was removed via centrifugation and cultures were inoculated onto inhibitory media plates, maintained at room temperature (20-22 C), and examined weekly for fungal growth. After 6 wk of incubation, ethanol, Virkon S (active ingredient potassium peroxymonosulfate 21.41%), benzalkonium chloride, and desiccation proved ineffective at completely inhibiting fungal growth. All other agents, including bleach, chlorhexidine, and accelerated hydrogen peroxides, effectively inhibited fungal growth. These data suggest that several effective disinfection options are available for use against E. testavorans. These findings can be used in managed care and field settings to reduce transmission of E. testavorans between turtles through contaminated surfaces and equipment.

To examine whether Ostertagia mossi and Ostertagia dikmansi from white-tailed deer (Odocoileus virginianus) are separate species, we obtained DNA sequences for the cytochrome C oxidase subunit I and internal transcribed spacer 2 gene targets for phylogenetic analyses. Neither target revealed separation between morphotypes, confirming they are the same species and providing new data on Ostertagia morphotypes.

Hepatitis E virus (HEV) is a globally distributed pathogen that causes acute hepatitis in people. Recent human cases of HEV arising after contact with urban rats (Rattus spp.) have raised concerns regarding whether rats may be a source of HEV infection. We investigated whether urban Norway rats (Rattus norvegicus) could be a source of HEV in an underserved urban neighborhood of Vancouver, Canada. We found that 15% of rats tested positive for rat HEV, and that HEV status was associated with increasing rat body length and family relationships. Rat HEV isolates were clustered according to their location on either the east or west side of a busy roadway bisecting this neighborhood, suggesting that this street is a barrier to HEV spread. Widespread distribution of HEV among rats in this neighborhood poses potential human health risks, emphasizing the need to reduce close contact of people with rats and their excreta.

Abstract: Klebsiella spp. are gram-negative facultative anaerobic heavily encapsulated bacteria associated with opportunistic and primary infections in a wide range of species. We assessed a series of cases (n=8) of necrosuppurative peritonitis, lymphadenitis, and/or pyelonephritis in wild juvenile raccoons (Procyon lotor) that died under rehabilitator care in New York, New Jersey, and Wisconsin, US, between July 2020 and December 2023, plus a retrospective case of a juvenile raccoon necropsied from New York in August 2011. Gross necropsy (n=9) and histopathology (n=9) were performed to characterize the lesions, whereas bacterial culture (n=8) was used to identify and characterize the bacteria and associated phenotype. We observed gram-negative short rods and coccobacilli (7/9; 78%), fibrinosuppurative peritonitis of variable severity (7/9; 78%) correlated to gross pyoabdomen (5/9; 56%) or abscessation (2/9; 22%), lymphadenomegaly and associated necrosuppurative lymphadenitis (5/9; 56%), and urinary tract disease (3/9; 33%). Aerobic culture of affected tissues isolated Klebsiella pneumoniae (n=4), K. pneumoniae subsp. ozaenae (n=2), Klebsiella variicola (n=1), and Klebsiella sp. (n=1). Our study strongly suggests an association of bacteria within the K. pneumoniae complex with peritonitis, lymphadenitis, and pyelonephritis in raccoons. Disease might be associated with underlying nosocomial infection given that all animals were under rehabilitator care at the time of death.

We collected and screened black rats (Rattus rattus) in Key Largo, Florida, USA, to determine the potential role of disease or parasites in the collapse of the local population. Rats appeared healthy, but 94% (n=15/16) tested positive for Sarcocystis sp. The partial 18S rRNA gene sequence was 98.7-99.7% similar to a strain of Sarcocystis zuoi that is now considered a strain of the newly described Sarcocystis kani within the larger S. zuoi species complex that contains numerous new species. These Sarcocystis spp. use Asian snakes as definitive hosts and rodents, shrews, or tree shrews as intermediate hosts. Pythons are the definitive host for several Sarcocystis spp. in Asia, including a related parasite (Sarcocystis singaporensis) that has been used as a biologic control agent for Rattus spp. in southeast Asia. It is probable that increasing numbers of invasive Burmese pythons (Python bivittatus) in the Florida Keys are contributing to the spread of this parasite in addition to imposing predation pressure on both rodents and native snakes. As such, further surveillance and molecular and morphologic characterization of parasites from rodents and snakes in south Florida should be prioritized.

The Wild Turkey (Meleagris gallopavo) is a geographically widespread, popular game bird and conservation icon in North America. Following successful reestablishment in parts of the US and Canada, regional declines have fueled population health concerns; therefore, understanding mortality causes and spatiotemporal patterns of disease is important to uncover potential ongoing and future health risks. Histomonosis, caused by the trichomonad Histomonas meleagridis, is a well-established and potentially fatal disease in Wild Turkeys; however, its prevalence and potential population health impacts remain poorly understood. Moreover, molecular tools recently have allowed for the detection of additional trichomonads that similarly can cause fatal disease in Wild Turkeys. We describe and compare disease due to H. meleagridis with that of Tetratrichomonas gallinarum, Tritrichomonas sp., and Simplicimonas sp. in Wild Turkeys in the southeastern US. Among 857 Wild Turkeys evaluated postmortem from 2002 to 2023, 34 (4.0%) were diagnosed with trichomonad disease, often assumed to be histomonosis prior to molecular testing. However, among 25 debilitating to fatal trichomonad disease cases for which etiologies were confirmed by PCR from 2015 to 2023, H. meleagridis was detected in 16/25 (64.0%), T. gallinarum in 6/25 (24.0%), Tritrichomonas sp. in 2/25 (8.0%) and Simplicimonas sp. in 1/25 (4.0%). These turkeys had similar clinical manifestations, and although lesion patterns varied to some extent, liver and/or intestinal tract was most commonly affected. Coinfections were common among all turkeys with trichomonad disease from 2015 to 2023 (21/25, 84.0%) and included viruses (lymphoproliferative disease virus, avian poxvirus), bacteria (Streptococcus gallolyticus, Listeria monocytogenes, Escherichia coli), and other protozoa (Sarcocystis sp., Haemoproteus sp.). Our results highlight the importance of molecular diagnostic testing in determining etiologies of trichomonad disease in Wild Turkeys. Further evaluation of the epidemiology and pathogenesis of trichomonad disease and its varied etiologies in Wild Turkeys and other birds is warranted to better understand risk factors and potential health impacts.

Book reviews express the opinions of the individual authors regarding the value of the book's content for Journal of Wildlife Diseases readers. The reviews are subjective assessments and do not necessarily reflect the opinions of the editors, nor do they establish any official policy of the Wildlife Disease Association.

Book reviews express the opinions of the individual authors regarding the value of the book's content for Journal of Wildlife Diseases readers. The reviews are subjective assessments and do not necessarily reflect the opinions of the editors, nor do they establish any official policy of the Wildlife Disease Association.

Polar bear (Ursus maritimus) life history is intimately associated with the distribution of sea ice and their prey in Arctic ecosystems. These ecosystems are changing in response to climate warming, resulting in the increased prevalence of pathogens in polar bears. Erysipelothrix rhusiopathiae has a long history of infection in domestic species and more recently in wildlife in the Canadian Arctic. As a result of increasing reports of E. rhusiopathiae causing morbidity and mortality in Arctic terrestrial mammals, we tested the seroprevalence of E. rhusiopathiae in Beaufort Sea polar bears sampled in 1985-87, 1992, 1994, and 2003-11. Our sample of 180 polar bears (117 females, 61 males, two unknown) with a median age of 9 yr (range 1-26 yr) had a seropositivity of 27.2% (49/180 individuals). We used binomial logistic regressions to investigate biotic and abiotic factors that may be linked to seropositivity. The resulting top model found that increased predation on adult ringed seals (Pusa [Phoca] hispida) and negative winter Arctic Oscillation Index (AOI) years were associated with a higher probability of seropositivity. Ringed seals may be a reservoir for E. rhusiopathiae via their consumption of infected prey, as the pathogen can persist in marine fish, molluscs, and crustaceans. Negative winter AOIs in our data set reflected high ice volume years, which reduced ringed seal natality, resulting in fewer seal pups available as prey. Our results suggest that exposure to E. rhusiopathiae in Beaufort Sea polar bears is modulated by a predator-prey mechanism.