Search Results (191)

Deer tick virus (DTV) is a Tick-Borne Orthoflavivirus endemic to the United States, transmitted to humans through bites from the deer tick, Ixodes scapularis, which is also the primary vector of Borrelia burgdorferi s.l., the causative agent of Lyme disease. Human infection with DTV can result in acute febrile illness followed by central nervous system complications, such as encephalitis and meningoencephalitis. Currently, there are mouse models established for investigating the pathogenesis and clinical outcomes of DTV that mimic human infections, but the strains of mice utilized are refractory to infection with B. burgdorferi s.l. Here, we describe the pathogenesis and clinical outcomes of DTV infection in C3H/HeJ mice. Neurological clinical signs, mortality, and weight loss were observed in all DTV-infected mice during the investigation. Infected animals demonstrated consistent viral infection in their organs. Additionally, neuropathology of brain sections indicated the presence of meningoencephalitis throughout the brain. This data, along with the clinical outcomes for the mice, indicates successful infection and showcases the neuroinvasive nature of the virus. This is the first study to identify C3H/HeJ mice as an appropriate model for DTV infection. As C3H/HeJ mice are already an established model for B. burgdorferi s.l. infection, this model could serve as an ideal system for investigating disease progression and pathogenesis of co-infections. Full article

White-tailed deer (Odocoileus virginianus) are a cervid species native to the Americas with ecological, social, and economic significance. Managers must consider several factors when working to maintain the health and sustainability of these wild herds, including reproduction, particularly pregnancy and recruitment rates. White-tailed deer have a variable reproductive capacity, with age, health, and habitat influencing this variability. However, it is unknown whether chronic wasting disease (CWD) impacts reproduction and, more specifically, if CWD infection alters a female deer’s probability of pregnancy. Our study addressed this question using data from 9783 female deer culled in northern Illinois between 2003 and 2023 as part of the Illinois Department of Natural Resources’ ongoing CWD management program. Multilevel Bayesian logistic regression was employed to quantify the relationship between pregnancy probability and covariates like maternal age, deer population density, and date of culling. Maternal infection with CWD was found to have no significant effect on pregnancy probability, raising concerns that the equal ability of infected and non-infected females to reproduce could make breeding, which inherently involves close physical contact, an important source of disease transmission between males and females and females and their fawns. The results also identified that female fawns (<1 year old) are sensitive to county-level deer land cover utility (LCU) and deer population density, and that there was no significant difference in how yearlings (1–2 years old) and adult (2+ years old) responded to these variables. Full article

Sin Nombre virus (SNV) is the main causative agent of hantavirus cardiopulmonary syndrome (HCPS) in North America. SNV is transmitted via environmental biological aerosols (bioaerosols) produced by infected deer mice (Peromyscus maniculatus). It is similar to other viruses that have environmental transmission routes rather than a person-to-person transmission route, such as avian influenza (e.g., H5N1) and Lassa fever. Despite the lack of person-to-person transmission, these viruses cause a significant public health and economic burden. However, due to the lack of targeted pharmaceutical preventatives and therapeutics, the recommended approach to prevent SNV infections is to avoid locations that have a combination of low foot traffic, receive minimal natural sunlight, and where P. maniculatus may be found nesting. Consequently, gaining insight into the SNV bioaerosol decay profile is fundamental to the prevention of SNV infections. The Biological Aerosol Reaction Chamber (Bio-ARC) is a flow-through system designed to rapidly expose bioaerosols to environmental conditions (ozone, simulated solar radiation (SSR), humidity, and other gas phase species at stable temperatures) and determine the sensitivity of those particles to simulated ambient conditions. Using this system, we examined the bioaerosol stability of SNV. The virus was found to be susceptible to both simulated solar radiation and ozone under the tested conditions. Comparisons of decay between the virus aerosolized in residual media and in a mouse bedding matrix showed similar results. This study indicates that SNV aerosol particles are susceptible to inactivation by solar radiation and ozone, both of which could be implemented as effective control measures to prevent disease in locations where SNV is endemic. Full article

This study extends the application of photothermal spectroscopy to explore heat transfer dynamics in biological fluids, focusing on the examination of artificial vitreous humor (VH) models of human VH and an endogenous sample of cervine (deer) VH. The research integrates previously established methods for analyzing thermal lensing through photothermal deflection. By visualizing convective and conductive heat transfer processes in the artificial components of human VH, one gains insights into the dynamic behavior of heat transfer in the VH. Relevance extends to clinical cases where pathology requires replacement of endogenous VH with an artificial VH substitute. Several VH substitutes identified in the literature were chosen for this study based on their physical properties and relative abundance in the VH. Individual component fluids, and mixtures of these components, were analyzed at various concentrations based on their physiological concentration ranges in the human VH as they varied with age, sex, and certain disease states. By way of comparison to endogenous biological VH, a sample of VH obtained from a female white-tailed deer eye was analyzed, enhancing the understanding of heat transfer in artificial components of the VH compared to endogenous VH. There is a vast array of ophthalmological procedures that utilize an external heat source interacting with endogenous or artificial VH. The data found in this study will progress the understanding of heat transfer within artificial VH components in comparison to endogenous VH and contribute to the advancement of certain ophthalmological procedures. Full article

Knowing the specific characteristics and animal tuberculosis risk factors present and applying good practices are crucial points in combating tuberculosis (TB) in a Mediterranean multi-species scenario. The objective of this work is to statistically analyze the association between the existence of TB in areas with a marked game–livestock interface, with various complementary factors found in 30 extensive farms in southern Portugal, such as the number of animals of each large game species present in the territory and the frequency of their sightings. Collecting this information, an inferential statistical analysis was conducted to obtain information on the association type between TB occurrence in the farms and the presence of highlighted factors. The main statistical results show an association between the presence of large game species and TB occurrence in the analyzed areas. Thus, in a multi-species scenario, large game species are a crucial component in TB maintenance, namely when stricter contact occurs. This could be one of the reasons why TB continues to circulate and why the eradication process is so difficult; the risk of zoonotic transmission is evident. It is crucial to apply biosecurity tools to improve the alignment and structure of natural resource management strategies. Full article

White-tailed deer (Odocoileus virginianus) in the wild and on cervid farms have drawn the attention of state wildlife agencies and animal health agencies as Chronic Wasting Disease (CWD) has spread across North America. Deer farm regulations have been implemented to reduce direct contact between wild and farmed cervids; however, evidence suggests that indirect contact to infectious prions passed through the alimentary tracts of scavengers may be an important transmission pathway. The objective of this study was to characterize mammalian scavenger and wild deer activities associated with deer farms and link these activities with site-specific spatial covariates utilizing a network of camera traps, mounted to farm perimeter fences. We monitored each of 14 farms in Minnesota, Wisconsin, and Pennsylvania for two weeks during the summer, with a subset of farms also monitored in the winter and fall. Across all sites and seasons, we captured 749 observations of wildlife. In total, nine species were captured, with wild white-tailed deer accounting for over three quarters of observations. Despite the large number of wild deer observed, we found that interactions between wild and farmed deer at the fence line were infrequent (six direct contacts observed). In contrast, mammalian scavengers were frequently observed inside and outside of the fence. Supplementary cameras placed on deer feeders revealed higher observation rates of scavengers than those placed along fence lines, highlighting the potential for transmission of CWD through indirect contact via scavenger excreta. To evaluate associations between the number of observations of focal species with land-cover characteristics, two mixed-effects regression models were fitted, one model for scavengers and one for wild deer. Contrary to our hypothesis, landscape context did not have a strong impact on wildlife visitation. This suggests that farm location is less important than management practices, highlighting the need for future research into how farming practices impact rates of wildlife visitation onto cervid farms. Full article

Hair, as a non-invasive biospecimen, retains metabolic deposits from sebaceous glands and capillaries, reflecting substances from the peripheral circulation, and provides valuable biochemical information linked to phenotypes, yet its application in animal disease research remains limited. This work applied ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) to compare the hair metabolomic characteristics of healthy forest musk deer (FMD, Moschus berezovskii) and those diagnosed with hemorrhagic pneumonia (HP), phytobezoar disease (PD), and abscess disease (AD). A total of 2119 metabolites were identified in the FMD hair samples, comprising 1084 metabolites in positive ion mode and 1035 metabolites in negative ion mode. Differential compounds analysis was conducted utilizing the orthogonal partial least squares–discriminant analysis (OPLS-DA) model. In comparison to the healthy control group, the HP group displayed 85 upregulated and 92 downregulated metabolites, the PD group presented 124 upregulated and 106 downregulated metabolites, and the AD group exhibited 63 upregulated and 62 downregulated metabolites. Functional annotation using the Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that the differential metabolites exhibited significant enrichment in pathways associated with cancer, parasitism, energy metabolism, and stress. Receiver operating characteristic (ROC) analysis revealed that both the individual and combined panels of differential metabolites exhibited area under the curve (AUC) values exceeding 0.7, demonstrating good sample discrimination capability. This research indicates that hair metabolomics can yield diverse biochemical insights and facilitate the development of non-invasive early diagnostic techniques for diseases in captive FMD. Full article

Prion diseases such as chronic wasting disease involve the conformational conversion of the cellular prion protein (PrP^C) into its misfolded, β-rich isoform (PrP^Sc). While chemical denaturants such as guanidine hydrochloride (GdnHCl) and urea are commonly used to study this process in vitro, their distinct molecular effects on native and misfolded PrP conformers remain incompletely understood. In this study, we employed 500 ns all-atom molecular dynamics simulations and essential collective dynamics analysis to investigate the differential effects of GdnHCl and urea on a composite PrP^C/PrP^Sc system, where white-tailed deer PrP^C interfaces with a corresponding PrP^Sc conformer. GdnHCl was found to preserve interfacial alignment and enhance β-sheet retention in PrP^Sc, while urea promoted partial β-strand dissolution and interfacial destabilization. Both denaturants formed transient contacts with PrP, but urea displaced water hydrogen bonds more extensively. Remarkably, we also observed long-range dynamical coupling across the PrP^C/PrP^Sc interface and between transiently bound solutes and distal protein regions. These findings highlight distinct, denaturant-specific mechanisms of protein destabilization and suggest that localized interactions may propagate non-locally via mechanical or steric pathways. Our results provide molecular-scale insights relevant to prion conversion mechanisms and inform experimental strategies using GdnHCl and urea to modulate misfolding processes in vitro. Full article

Wildlife serves as a significant reservoir for various pathogens transmissible to domestic animals and humans. Vector-borne diseases represent an increasing concern in Europe, affecting both animal and human health. This pilot study investigated the circulation of endemic and emerging vector-borne viruses in wild ungulates in Hungary, utilizing a One Health approach. Serum samples were obtained from European fallow deer (Dama dama), red deer (Cervus elaphus), and roe deer (Capreolus capreolus) during routine national game management activities between 2020 and 2023. Samples were analyzed for antibodies against the Bluetongue virus (BTV), West Nile virus (WNV), and Epizootic hemorrhagic disease virus (EHDV) using ELISA and neutralization tests. The results revealed a WNV seroprevalence of 22.3% in fallow deer and 31.8% in red deer, while BTV seroprevalence was 2.5% in fallow deer. All samples were negative for EHDV antibodies. These findings confirm the circulation of WNV and BTV in Hungarian wild ungulates. While the study’s design precludes statistical analysis due to non-random sampling, it demonstrates the potential of integrating wild ungulate serosurveillance into disease monitoring programs, leveraging established wildlife management activities for a cost-effective and complementary approach to One Health surveillance, particularly considering the ongoing spread of EHDV in Europe and the importance of BTV serotype monitoring for effective vaccination strategies. Full article

This study investigates the recombinant Tarim red deer hepatocyte growth factor (HGF) in a mouse model to develop an HGF/c-Met-based regenerative therapy for alcoholic liver disease. We constructed a recombinant HGF fusion protein and expressed and purified it in Escherichia coli. The recombinant protein was administered via intravenous injection to treat mice with alcoholic liver disease induced by chronic alcohol feeding followed by acute alcohol gavage (NIAAA model). The therapeutic effects were evaluated based on liver tissue histology and biochemical indicators. The recombinant Tarim red deer HGF protein successfully reduced serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in mice, increased serum albumin (ALB) levels, decreased hepatic steatosis and triglyceride (TG) levels, lowered hepatic malondialdehyde (MDA) levels, and increased the levels of the antioxidants glutathione (GSH) and superoxide dismutase (SOD) in the liver. Additionally, it enhanced the proliferation capacity of liver cells, thereby promoting liver regeneration. In conclusion, our study demonstrates that recombinant Tarim red deer HGF effectively reduces liver damage in a mouse model of alcoholic liver disease. Full article

Dictyocaulosis is a parasitic disease that affects ungulate species, including red deer (Cervus elaphus). The genus Dictyocaulus comprises eighteen species, but only four have been reported to infect red deer. The disease is characterized by respiratory tract infection, particularly in the lungs, bronchi, and bronchioles, leading to inflammatory and hemorrhagic microscopic lesions, as well as emphysema and edema. The biological cycle involves a female ovipositing larvated eggs in the bronchi and trachea, which are expelled to the exterior through coughing or feces, releasing L1 into the environment. In this study, 106 adult red deer were collected from seven locations in Extremadura (Spain). Eight positive lungs were initially assessed by morphological identification, revealing a mean intensity of 13.3 adult worms per infected lung, with a global decrease to an average of 1.8 adult worms per sampled lung. The presence of adult worms in the upper and middle respiratory tract was confirmed through anatomopathological analysis. Molecular identification was performed by sequencing the COI gene. The results indicated the presence of three genetic groups, supported by significant subdivision using the ɸ_ST measure. D. cervi and D. viviparus exhibited their respective matrilineal ancestry, while D. eckerti and D. cervi demonstrated matrilineal sharing. Consequently, the possibility of introgression between these two species was suggested. Although D. viviparus had previously been identified in the same Spanish region based on morphological characteristics, D. cervi and D. eckerti were reported for the first time in the explored geographic area. Full article

Ticks carry a range of pathogens, the best known of which causes Lyme disease, prevalent in the northeastern United States. Emerging diseases do not yet consist of a wide range of Lyme diseases, raising the question of how long it takes for a newly introduced tick-borne disease to establish itself. The aim of this study was to address this question, with the agent of Lyme disease used as the test case. A prior process-based model of the Ixodes scapularis (Say 1821) life cycle and the transmission of Borrelia burgdorferi (Burgdorfer 1982) between this tick and its various hosts was used to predict the dynamics of disease introduction into a new area. The importance of temperature, infection probabilities, and tick host populations, relative to that of other factors, was established by a global sensitivity analysis using Latin hypercube sampling. The results of those samples were analyzed to determine the time to near-equilibrium. Eight locations in New Hampshire were chosen for high/low temperature, high/low mouse, and high/low deer values. Mammal abundance was estimated by relating the known mammal density from previous studies to a MaxEnt analysis output. The time required to reach Borrelia endemicity in the ticks of New Hampshire ranged from 8 to 20 years in regions where the tick population is viable, with a strong dependency on susceptible tick host populations. Full article

Piroplasmids (Babesia spp., Rangelia spp., Theileria spp., Cytauxzoon spp.) are tick-borne apicomplexan protozoa that infect, depending on the species, erythrocytes and leucocytes in a wide variety of mammals and birds. The genera Bartonella and Borrelia include vector-borne bacteria that can infect and cause disease in both animals and humans. Detection of hemotropic bacteria and piroplasmids in wild animals is often challenging due to low bacteremia or parasitemia. Digital (d)PCR has proven to be an effective modality for the detection and quantification of DNA of hemotropic pathogens with low parasitemia. This study compared dPCR results from 366 biological samples from seven different Brazilian wild animal groups (5 Xenarthra species, 5 deer species, 3 felid species, 1 canid species, 3 rodent species, 1 bat species, 1 tapir species, and 12 bird species) to two other molecular diagnostic techniques: quantitative real-time (qPCR) and nested (nPCR). For this study, DNA extracted from wild animal blood and spleen samples were subjected to a multiplex dPCR assay for piroplasmids, Bartonella spp., and Borrelia spp. For comparison, the same primers and probes for each agent were used in qPCR assays. Additionally, an nPCR based on the 18S rRNA gene for piroplasmids was performed. The proportions of positive results obtained using dPCR were 85.5% for piroplasmids, 33.6% for Bartonella spp., and 16.7% for Borrelia spp. For all tested agents, dPCR proved to be the technique with the highest sensitivity, making it a useful tool for screening vector-borne agents in biological samples from wild animals with low parasitemia. Full article

Considering the taxonomic uncertainties of Neotropical deer species, as well as the threat status of many of them, new studies and strategies for their maintenance are urgently needed. Obtaining live cells is of great importance for the conservation of wild species in order to allow cytogenetic and molecular studies to be carried out and for the construction of genomic resource banks. In order to increase the genetic diversity stored in these banks, the possibility of collecting skin fragments from dead animals (e.g., run over, hunted, deaths related to disease or natural causes) becomes a valuable source and a last alternative for obtaining material from these individuals. However, the interval between the death of the animal and the collection of tissue can directly interfere with the quality of the sample obtained and it is therefore essential to identify the maximum time during which viable cells are still found. Thus, this study sought to establish a protocol for the collection, storage, cryopreservation, and cultivation of skin obtained postmortem from individuals of the species Subulo gouazoubira (gray brocket deer) and Mazama rufa (red brocket deer). The collection of tissue fragments at different postmortem intervals (0 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, and 11 h) was evaluated. The tissues were analyzed for fibroblast cell viability immediately after collection. Their ability to undergo cryopreservation was evaluated based on techniques that can be directly applied to samples obtained in the field and their subsequent thawing and success of cell cultures was performed in the laboratory. Regarding the genetic integrity of the cells, the number of metaphases was observed by the mitotic index. The cell viability presented by the samples always remained above 60%. It was possible to establish cell cultures even with the tissues obtained 11 h after the death of the individuals; however, they required twice as many days to reach bottle confluence compared to the cultures performed with the tissues obtained 0 h after the death of the individuals. The results suggest that the best rates of cell viability, time to reach confluence, and number of metaphases per cell (mitotic index) are found in skin fragments collected up to 5 h after the death of individuals when their carcasses are kept at room temperature. Full article

Diarrhea is a common disease in sika deer. The causes of diarrhea in sika deer are complex and involve a variety of pathogens. Additionally, new virulent pathogens are continuously emerging, which poses a serious threat to deer’s health and particularly affects fawns’ survival rate. In the present study, feces samples were collected from fawns with diarrhea in Jilin Province, in the northeast of China. The viral communities were investigated using the metagenomic method. Viral metagenome data revealed that the viruses in the fecal samples were mainly from 21 families in 14 orders. The major viruses in high abundance were astrovirus, rotavirus, coronavirus, and bovine viral diarrhea virus. In addition, a large number of phages, which mainly belonged to the family Siphoviridae, were identified. Then, the known causative virus species were investigated via RT-qPCR. The results showed that the infection rates of bovine coronavirus, bovine rotavirus, and bovine viral diarrhea virus were 59.44%, 58.89%, and 21.67%, respectively, and mixed infections were commonly seen in the samples. A bovine rotavirus strain was successfully isolated from the positive samples. Whole-genome sequencing revealed that the genotype of the strain was G6-P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3, indicating the recombination of rotavirus. This study revealed the profiles and characteristics of viruses that cause sika deer diarrhea, which will be helpful for understanding diarrhea diseases in sika deer. Full article