Journal of Wildlife Diseases最新文献

Hematologic parameters from free-ranging screaming hairy armadillos, Chaetophractus vellerosus, were determined by hemocytometry and blood smear review. Packed cell volume was higher and basophil and eosinophil counts lower than those reported for this species in captivity. These findings will serve as a reference for future research.

We diagnosed and molecularly confirmed the presence of fibropapillomatosis and chelonid alphaherpesvirus 5 infection in one Kemp's ridley sea turtle (Lepidochelys kempii) and three green sea turtles (Chelonia mydas) stranded on the Mississippi, USA, coast, expanding the known range of this disease in sea turtles in the Gulf of Mexico.

A radiographic analysis of fractures and/or luxations in raptors was conducted across two wildlife centers, one in Brazil (Center for Medicine and Research in Wild Animals [CEMPAS]; n=106 raptors) and the other in the USA (Lindsay Wildlife Experience [LWE]; n=310 raptors), through a data study spanning 7 yr. There were differences between the two centers in which order was most affected. At CEMPAS, Strigiformes accounted for 48.1% of the cases, but at LWE Accipitriformes were most affected (59.4% of cases). The axial skeleton was least affected at both centers, with two cases at CEMPAS and three cases at LWE. Most fractures included a single bone in the appendicular skeleton, accounting for 57.7% at CEMPAS and 61.9% at LWE. In the thoracic limb, the humerus was the most fractured bone at CEMPAS (44/108), whereas the ulna was most commonly fractured at LWE (116/307). In the pelvic limb, the tibiotarsus was the most fractured bone at both centers (23/35 at CEMPAS and 27/80 at LWE). Closed fractures were more frequent in the thoracic and pelvic limbs at both centers. Cases of luxation or subluxation without fractures were less common, with 6.7% at CEMPAS and 7.2% at LWE. The types of fractures and/or luxations identified in this study exhibited several similarities between centers that may be useful in understanding these lesions in raptors and establishing future treatment protocols.

Rats are managed using anticoagulant rodenticides (ARs) in cities worldwide, but these compounds cause morbidity and mortality in nontarget wildlife. Several cities also use free-roaming outdoor cat (Felis catus) colonies to help reduce rats, but there have been no investigations of how often these cats are exposed to ARs. In this study, our goal was to assess how often free-roaming domestic cats are exposed to ARs to 1) understand health risks for urban predators by using free-roaming cats as a proxy and 2) evaluate the health risks associated with using cats as rodent control. We tested blood samples from 57 cats that were part of trap-neuter-release cat colonies in Chicago, Illinois, USA. We found that 7% (4/57) of cats tested positive for one type of rodenticide at trace amounts. Free-roaming cats can therefore be exposed to ARs, although the prevalence and concentrations were lower than in wild carnivores. Future research is needed to understand how often cats may be exposed to ARs by killing or consuming rats and any health impacts. Stronger rodenticide regulations are needed to reduce health risks for urban predators, and owned cats should be kept indoors to minimize the risk of rodenticide exposure.

We describe hepatic infections by giant liver fluke (Fascioloides magna) in free-ranging muskoxen (Ovibos moschatus) in Nunavik, Québec, Canada. Whole livers and feces were collected from 51 muskoxen (37 males, 14 females) harvested from 2007 to 2011. Prevalence of F. magna was very high (48/51, 94%; 95% confidence interval, 84-99), with the intensity of infection reaching up to 40 adult trematodes per liver (median, 4 flukes). The estimated percentage of macroscopically altered liver, which was evaluated in serial 1-cm-thick slices, ranged from 0.1% to 57.3% and was positively correlated with the number of parasites detected. Animals harvested near Tasiujaq had higher mean fluke intensity (7.2) than those near Kuujjuaq (2.6) in Nunavik, Québec, Canada. Despite the extent of the hepatic alterations in some individuals, no association was found between intensity of infection or liver alteration and the examined nutritional condition indices (depth of back fat, femur marrow fat percentage, and kidney fat index). Field observations suggest that infections by F. magna did not have a significant clinical impact on sampled muskoxen. The mean fluke intensity and the percentage of altered liver did not vary between sex and age. Fecal shedding of F. magna eggs was documented in some individuals, indicating that muskoxen could be characterized as a definitive host. Further research is needed to define the reservoir species and characterize the life cycle of this parasite in the Canadian Arctic.

Diagnosing the cause of peracute death in wildlife is challenging, particularly when necropsy, histopathology, and ancillary testing yield nonspecific results. Biochemistry could provide pathophysiologic information on the death process that is unobtainable with morphologic methods. To evaluate the impact of postmortem delay on the quality of blood biochemical analysis, blood samples were collected from 20 wild boars (Sus scrofa) hunted in January 2018 in France. The body condition, age, and sex of each boar were recorded. Each animal was sampled once between the time of death and 6 h postmortem, with six boars sampled within the first hour, three boars sampled at each hour thereafter (hours 2-5), and two boars sampled at 6 h postmortem. Samples were promptly sent to the laboratory, centrifuged, and assessed for hemolysis before measurement of biochemical parameters using a wet chemistry analyzer. The first component from a principal component analysis was used as a quality index of the biochemical composition of the blood. This index strongly correlated positively with sodium and chloride and negatively with total proteins, alanine aminotransferase, fructosamine, and potassium. A segmented regression analysis indicated stability of blood quality for 2 h after death, followed by a linear decrease. Practically, blood samples drawn within 2 h after death maintained overall quality. This exploratory study should be expanded with evaluations of changes of individual metabolites over time.

Detections of highly pathogenic avian influenza viruses in mammals have increased globally, underscoring the need to assess influenza A virus (IAV) exposure in species that bridge wildlife, livestock, and human interfaces. We collected serum from 396 wild pigs (Sus scrofa, hybrids of wild boar and domestic swine) between October 2022 and May 2023 on a cattle ranch in north central Texas, USA, to estimate IAV seroprevalence and identify ecologic correlates of exposure. Using commercial blocking ELISAs and hemagglutination inhibition assays, we report high recent exposure of wild pigs to IAVs (seroprevalence 40%, n=396). Seropositivity was highest in individuals that were female, >2 yr old, sampled during spring (compared with fall or winter), and/or sampled <1.5 km from surface water. Almost half (46.3%, 57/123) of the samples were positive for at least two hemagglutinin clade representatives, and 13.8% (17/123) had titers against both an H1 and an H3 strain. These results indicate a hotspot of IAV circulation in wild pigs in north central Texas and highlight elevated exposure near water bodies, where wild pigs may contact wild waterfowl. Enhanced surveillance of wild pigs at the wildlife-livestock-waterbird interface is warranted to better understand ecologic and epidemiologic pathways for IAV transmission and reassortment.

Dystocia, a complication that occurs at parturition, either due to fetal or maternal factors, is uncommon in wild ungulate species because of natural selection against predisposed individuals. Among giraffes, reports of dystocia are rare in free-ranging populations across Africa. This study reviewed occurrence and type of dystocia, and outcome of obstetrical interventions, in giraffes in Kenya during 1991-2023 and considered possible risk factors. Only one case of dystocia in a semicaptive and one case in a captive northern (Rothschild's) Rothschild's giraffe (Giraffa camelopardalis) had been reported in Kenya before 2012. Seventeen cases were recorded in free-ranging giraffes during 2012-23 in 10 different protected areas with variable range and forage restrictions, associated with fenced, partially fenced, or unfenced management systems. In the latter period, three giraffe species found in Kenya were all affected, with nine cases in Masai giraffes (Giraffa tippelskirchi) and four cases each in reticulated giraffes (Giraffa reticulata) and Rothschild's giraffes. Cases were attributed to fetal factors, including malposition that refers to the position of the fetus or to malpresentation that refers to parts of the body presenting on the pelvis. Potential maternal factors were not evaluated in any individuals. Based on dam survival, 75% success rate relieving dystocia, through obstetrical manipulation, was recorded, but none of the calves survived. We postulate that dystocia might be increasing in Kenya, although increased reports may simply reflect improving capacities to observe and intervene.

The collection and storage of swab samples for molecular diagnostics is a routine component of wildlife health surveillance. The suitability of different sample storage conditions for maximizing the recovery of pathogen DNA in most species has not been assessed; therefore, the aim of this study was to identify a preferred storage method for swabs collected for the detection of frog virus 3 (FV3), a significant chelonian pathogen. Sterile swabs were inoculated in triplicate with a plasmid containing known quantities of FV3 DNA from 100 to 107 copies. Swabs were then stored under one of the following four conditions: 1) dry frozen at -20 °C; 2) immersed in phosphate-buffered saline (PBS) and frozen at -20 °C; 3) immersed in a nucleic acid preservative (RNAlater) and frozen at -20 °C; and 4) immersed in 100% ethanol at ambient room temperature. Swabs remained undisturbed under designated storage conditions for 14 d, at which point DNA extraction and conventional and quantitative PCR for FV3 detection were performed. Conventional PCR amplified down to the lowest expected FV3 target copy number (10,000 copies/swab) for the dry-frozen and PBS-frozen treatment groups. Conventional PCR amplification was inconsistent for the ethanol and RNAlater treatment groups. Quantitative PCR on dry-frozen samples successfully amplified as low as 100 FV3 target copies/swab with a mean recovery of 90%, with all other storage methods amplifying only down to 10,000 copies/swab. Findings suggest there is improved detection of pathogen DNA for samples stored from collection to extraction under the dry-frozen method. Swab sample storage recommendations for future applications should be observed within the context of study-specific objectives and target pathogens. Furthermore, failure to detect fewer than 100 copies/swab of FV3 from any storage method may have clinically significant ramifications and suggests that the differences in DNA recovery based on extraction method should also be examined.

This study detected Trichomonas gypaetinii in Black-tailed Gulls (Larus crassirostris) in South Korea. We collected 83 samples (80 oropharyngeal swabs from live birds and three carcass-derived specimens) from breeding colonies on Nando and Hongdo islands and coastal habitats in Taean, South Korea, in 2023-24. Molecular analysis using nested PCR targeting the ITS region revealed an exceptionally high prevalence (98.8%) of Trichomonas spp., with both Trichomonas gallinae and Trichomonas gypaetinii identified. We observed significant seasonal variation in Trichomonas spp. distribution, with T. gallinae predominating in winter (85%), while T. gypaetinii became more prevalent during breeding and migration periods (67%). Co-infections were documented at both breeding colonies, suggesting potential interspecies interactions. Sex-based differences in infection patterns were statistically significant (P<0.05); T. gypaetinii showed higher prevalence in adult males at Nando Island (88%) and in adult females at Hongdo Island (88%). Despite the high infection rate, no distinctive lesions were observed in examined carcasses, raising questions about pathogenicity and host adaptation. These findings expand the known host range of this protozoan parasite beyond raptors. This, together with previous detection of T. gallinae in other seabird species (Streaked Shearwater [Calonectris leucomelas] and Swinhoe's Petrel [Hydrobates monorhis]), highlights the need for expanded surveillance of Trichomonas spp. in nonraptor species and further investigation into transmission dynamics, pathogenicity, and potential impacts on reproductive success and population health in colonial nesting birds.