Journal of Wildlife Diseases最新文献

Owls play an important role as avian hosts for hemosporidians via overlap in habitat use and activity with these arthropod vectors, thereby resulting in susceptibility to morbidity and, in some cases, mortality upon infection. This study analyzed the hemosporidians in tissues collected from individual dead owls (n=240) in various regions of mainland Portugal; the owls were primarily obtained from wildlife rehabilitation centers (WRCs). Hemosporidian species were detected using nested PCRs, targeting the cytochrome b gene of the mitochondria. For species and lineage identification, 19 positive PCR samples were selected and sequenced by the Sanger method. In total, 51% (n=122) of the 240 owl samples tested positive for at least one hemosporidian species: 31% (n=75) were positive for Haemoproteus-Plasmodium spp., whereas 44% (n=106) were positive for Leucocytozoon spp. Only 7% (n=16) were positive for Haemoproteus-Plasmodium spp. alone and 20% (n=47) for Leucocytozoon spp. alone, whereas 25% (n=59) of owls had mixed infections. Owl species, age, and geographic region of collected samples were significantly associated with hemosporidian prevalence: Eurasian Eagle-Owls (Bubo bubo), adults, and individuals from the Alentejo region presented higher prevalences than other species, ages, and geographic regions. Our findings highlight the potential impact of hemosporidians on owl conservation, particularly their effect on species currently threatened with extinction and the possible repercussions on reintroduction or translocation projects. This study emphasizes the role of WRCs in disease surveillance and suggests the importance of considering prophylactic measures in these settings. Given the high prevalence of hemosporidians, further studies involving live owls, both wild and captive, are encouraged, along with integrating clinical and hematologic data.

From 2017 to 2023, 196 dead Korean water deer (Hydropotes inermis argyropus), a common wildlife species in Republic of Korea, were necropsied. In one deer, bovine tuberculosis infection was confirmed through necropsy, histopathologic examination, and microbiologic diagnosis.

Abstract: Baylisascaris procyonis, a nematode parasite of raccoons (Procyon lotor), has important implications for human health and ecological conservation. Several techniques are available for detecting B. procyonis, and it is important to consider their limitations for the specific question to be answered. The sensitivity of molecular tools to detect B. procyonis in comparison to traditional methods is unknown. We compared the sensitivity fecal flotation with PCR to identify raccoons infected with B. procyonis as determined by seeing worms at necropsy. We collected 2-6 g of fecal material from along the ascending, transverse, and descending colon of 31 raccoons, resulting in 48 fecal samples across 31 individuals. Samples were aliquoted into two sets to compare fecal flotation and PCR. Of the 31 raccoons, 7/31 (23%) were infected with B. procyonis, but fecal flotation analysis identified only 4/31 positive raccoons (13%). Using fecal flotations from known positive individuals, 4/10 (40%) were positive, but PCR did not discover any infected individuals. Our results demonstrate the importance of using multiple techniques to confirm B. procyonis presence or absence. Dissection of raccoon intestines is the most sensitive technique because it enables visualization of worms. Fecal flotations remain the most efficient method of determining environmental prevalence and positive individuals from fecal sampling. Although PCR is technically very sensitive, it is limited by the quality and quantity of DNA in a sample.

Leptospirosis is a bacterial zoonosis impacting wild and domestic animals globally. Leptospira interrogans serovar Pomona is endemic in free-ranging California sea lions (CSLs; Zalophus californianus), and leptospirosis is frequently diagnosed in stranded CSLs. Serum microscopic agglutination test (MAT) is a commonly performed diagnostic assay, and CSLs with clinical disease have reliably elevated MAT titers. However, MAT results may not be available for several days after sampling. Given the zoonotic and high transmission potential of Leptospira spp., a point-of-care diagnostic test would be valuable in rehabilitation and managed care settings and during outbreak response efforts. The ID SNAP and Zoetis WITNESS anti-Leptospira antibody tests are rapid diagnostic tools that have been validated in dogs and give a qualitative (positive or negative), not quantitative (exact titer), result. The SNAP test uses ELISA to detect both immunoglobulin (Ig)M and IgG antibodies, whereas the WITNESS test is a lateral flow assay that only detects IgM. We compared SNAP and WITNESS results with MAT results by using serum collected from stranded and free-ranging CSL with negative, low, medium, and high anti-Leptospira antibody titers as previously determined by MAT. Percent agreement between SNAP and MAT results was high, with a Cohen's kappa statistic of 0.957. No WITNESS tests were positive. These findings suggest that the SNAP test may be useful for detecting anti-Leptospira antibodies and ruling out leptospirosis in CSL.

Double-crested Cormorants (Nannopterum auritum) have historically exhibited low levels of infection and antibodies to avian influenza virus (AIV). The recent global expansion of clade 2.3.4.4b A/goose/Guangdong/1/1996 highly pathogenic (HP) avian influenza virus H5N1 (HPAI H5N1) has resulted in large-scale mortalities across diverse waterbird taxa including cormorants. We sampled 32 and 29 Double-crested Cormorants breeding in the Chesapeake Bay, US, during the summers of 2023 and 2024, respectively, to assess HPAI H5N1 infection and AIV antibodies. Although no mortality was observed in the area, one bird sampled in 2023 was infected with HPAI H5N1. Additionally, 21/31 individuals in 2023 and 10/25 individuals in 2024 for which sera were collected had AIV antibodies. Based on additional testing using hemagglutination inhibition, virus neutralization, and an enzyme-linked lectin assay, 94 and 100% (2023 and 2024, respectively) of the seropositive birds tested positive for antibodies to both H5 and N1, suggesting previous infection with HPAI H5N1. These results are consistent with survival and limited clinical effects related to HPAI H5N1 infections. Furthermore, these results suggest that population immunity to HPAI H5N1 within the Chesapeake Bay might reduce future infections and potential population impacts should HP H5N1 remain on the landscape, though immunity may be waning across time. Because results are based on a single population, additional testing for both infection and antibodies as well as continued monitoring could enhance understanding of antibody persistence.

Rehabilitation and release of wild birds hinge upon a comprehensive understanding of both biologic and nonbiologic factors, including the medical and physical fitness of the animal. The objectives of this study were to determine reference intervals of packed cell volume and plasma chemistry values for healthy Eurasian Eagle Owls (Bubo bubo) and to compare blood values between age and sex classes. There were significant differences between males and females in total protein and globulin mean values, with males having higher values than females. Adult and juvenile Eagle Owls differed significantly in the mean values of calcium, alkaline phosphatase, and uric acid, with juveniles having higher values than adults. The calculated reference intervals for Eagle Owls can be used in Eurasian Eagle Owls admitted to rescue centers to assist veterinarians and wildlife managers to clinically evaluate and monitor the health of Eagle Owls and make decisions about when to release them after treatment.

We investigated the prevalence of arthropod-borne viral diseases in a population of free-ranging mantled howler monkeys (Alouatta palliata) in Costa Rica in 1998. Blood samples were opportunistically collected from monkeys anesthetized for another study. Serology was performed on 64 individuals to assess exposure of this population to vesicular stomatitis virus, equine encephalitis viruses, Mayaro virus, St. Louis encephalitis virus, yellow fever virus, and dengue virus. The New Jersey serotype of vesicular stomatitis (VSV-NJ) was the only pathogen for which the population tested positive (44% [28/64]). This is the first report of antibodies against VSV-NJ in nonhuman primates in Costa Rica.

Ectoparasite loads of birds may be governed, in part, by the climatic characteristics of their environment. We surveyed live-trapped American Kestrels (Falco sparverius caribaearum) for lice and other ectoparasites on the humid subtropical island of Puerto Rico during March-May 2024. The main goal was to compare the prevalence and abundance of lice on kestrels in Puerto Rico to recently published data on the lice of kestrels 1000 km away in the Bahamas, and to the lice of kestrels in an arid region of the western US (Utah). A brief general inspection of the plumage of 39 captured birds was followed by careful examination of the underside of wing primary feathers under a dissecting microscope. Two species of lice were collected, Colpocephalum subzerafae and Degeeriella carruthi, neither previously recorded from kestrels in Puerto Rico. The same two species are present on kestrels in the Bahamas. The prevalence and abundance of lice on kestrels in Puerto Rico and the Bahamas were similar, while being much greater than the prevalence and abundance of lice on kestrels in arid Utah, US. We also collected two species of hippoboscid flies (Diptera: Hippoboscidae): Microlynchia pusilla, not previously recorded on the American Kestrel, and Ornithoctona erythrocephala. These flies, as well as the lice, might affect the health of kestrels both directly, e.g., causing anemia by feeding on blood, and indirectly by vectoring endoparasites.

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.

Molecular approaches are becoming more prevalent for the diagnosis of neurodegenerative diseases in human medicine and can be extended to diagnosis of wildlife diseases such as chronic wasting disease and other prion diseases. These diseases have been associated with exosome-bound molecular biomarkers of disease progression, such as proteins and micro RNA molecules (miRNA). We tested and optimized a method for exosomal miRNA isolation from minimally invasive, small-volume serum samples obtained from white-tailed deer (Odocoileus virginianus). We confirmed the isolation of exosomes and optimized a commercially available benchtop kit to obtain sufficient and pure RNA for miRNA sequencing. The selected method for RNA extraction combines two 500-μL serum aliquots into one elution column and re-eluting the final product of the column. We identified 137 miRNA present in healthy white-tailed deer that can be used as a baseline to identify putative miRNA biomarkers of disease progression and mechanisms of infection in future comparative disease studies. This approach to biomarker discovery may help to inform biological processes in wildlife populations and provide alternatives to invasive or postmortem samples.