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Paleoparasitology – Human Parasites In Ancient Material, Adauto Araújo, Karl Reinhard, Luiz Fernando Ferreira

Karl Reinhard Publications

Parasite finds in ancient material launched a new field of science: paleoparasitology. Ever since the pioneering studies, parasites were identified in archaeological and paleontological remains, some preserved for millions of years by fossilization. However, the paleoparasitological record consists mainly of parasites found specifically in human archaeological material, preserved in ancient occupation sites, from prehistory until closer to 2015. The results include some helminth intestinal parasites still commonly found in 2015, such as Ascaris lumbricoides, Trichuris trichiura and hookworms, besides others such as Amoebidae and Giardia intestinalis, as well as viruses, bacteria, fungi and arthropods. These parasites as a …

Electrostatic Charge On Flying Hummingbirds And Its Potential Role In Pollination, Marc Badger, Victor Manuel Ortega-Jimenez, Lisa Von Ribenau, Ashley Smiley, Robert Dudley, Alexei Gruverman , Editor

Alexei Gruverman Publications

Electrostatic phenomena are known to enhance both wind- and insect-mediated pollination, but have not yet been described for nectar-feeding vertebrates. Here we demonstrate that wild Anna's Hummingbirds (Calypte anna) can carry positive charges up to 800 pC while in flight (mean ± s.d.: 66 ± 129 pC). Triboelectric charging obtained by rubbing an isolated hummingbird wing against various plant structures generated charges up to 700 pC. A metal hummingbird model charged to 400 pC induced bending of floral stamens in four plants (Nicotiana, Hemerocallis, Penstemon, and Aloe spp.), and also attracted falling Lycopodium spores at distances of < 2 mm. Electrostatic forces may therefore influence pollen transfer onto nectar-feeding birds.

Wildland Fire Deficit And Surplus In The Western United States, 1984–2012, Sean A. Parks, Carol Miller, Marc-André Parisien, Lisa M. Holsinger, Solomon Z. Dobrowski, John Abatzoglou

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Wildland fire is an important disturbance agent in the western US and globally. However, the natural role of fire has been disrupted in many regions due to the influence of human activities, which have the potential to either exclude or promote fire, resulting in a ‘‘fire deficit’’ or ‘‘fire surplus’’, respectively. In this study, we developed a model of expected area burned for the western US as a function of climate from 1984 to 2012.We then quantified departures from expected area burned to identify geographic regions with fire deficit or surplus. We developed our model of area burned as a …

Patterns Of Substance Use Initiation Among Indigenous Adolescents, Les B. Whitbeck, Brian E. Armenta

Department of Sociology: Faculty Publications

Background—The data for this study come from an eight-wave panel study of Indigenous (Canadian First Nations and American Indian) adolescents from three U.S. reservations and four Canadian reserves.

Objectives—Our objective was to investigate variations in patterns of substance use initiation from early adolescence through early adulthood using data collected annually for 8 years.

Method—At baseline the sample included 675 Indigenous adolescents (M age = 11.10, SD = .83; 50.3% girls). First, we calculated cumulative rates of substance use initiation by age. We then examined whether the cumulative initiation rates were moderated by gender using logistic regression …

Widespread Detection Of Antibodies To Leptospira In Feral Swine In The United States, K. K. Pedersen, K. L. Pabilonia, T. D. Anderson, S. N. Bevins, C. R. Hicks, J. M. Kloft, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

As feral swine continue to expand their geographical range and distribution across the United States, their involvement in crop damage, livestock predation, and pathogen transmission is likely to increase. Despite the relatively recent discovery of feral swine involvement in the aetiology of a variety of pathogens, their propensity to transmit and carry a wide variety of pathogens is disconcerting. We examined sera from 2055 feral swine for antibody presence to six serovars of Leptospira that can also infect humans, livestock or domestic animals. About 13% of all samples tested positive for at least one serovar, suggesting that Leptospira infection is …

Anticoagulant Rodenticide Exposure And Toxicosis In Coyotes (Canis Latrans) In The Denver Metropolitan Area, Sharon A. Poessel, Stewart W. Breck, Karen A. Fox, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Anticoagulant rodenticides are widely used in urban areas to control rodent pests and are responsible for secondary poisoning in many nontarget wildlife species. We tested the livers of five coyotes (Canis latrans) in the Denver Metropolitan Area, Colorado, US, for anticoagulant rodenticides. All five livers were positive for brodifacoum, with values ranging from 95 ppb to 320 ppb, and one liver was positive for bromadiolone, with a value of 885 ppb. Both of these rodenticides are second-generation anticoagulants, which are more potent and more likely to cause secondary poisoning than first-generation anticoagulants due to their accumulation and persistence …

A Behaviorally-Explicit Approach For Delivering Vaccine Baits To Mesopredators To Control Epizootics In Fragmented Landscapes, James C. Beasley, Todd C. Atwood, Michael E. Byrne, Kurt C. Vercauteren, Shylo R. Johnson, Olin E. Rhodes Jr.

United States Department of Agriculture Wildlife Services: Staff Publications

Despite the widespread use of aerial baiting to manage epizootics among free-ranging populations, particularly in rabies management, bait acceptance and seroconversion rates often are lower than required to eliminate spread of disease. Our objectives in this study, therefore, were to evaluate the performance of stratified bait distribution models derived from resource selection functions (RSF) on uptake of placebo rabies baits by raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana), as well as the probability of bait uptake as a function of proximity to bait distribution areas in fragmented agricultural ecosystems. Among 478 raccoons and 108 opossums …

Evaluating And Validating Abundance Monitoring Methods In The Absence Of Populations Of Known Size: Review And Application To A Passive Tracking Index, Lee R. Allen, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Rarely is it possible to obtain absolute numbers in free-ranging populations and although various direct and indirect methods are used to estimate abundance, few are validated against populations of known size. In this paper, we apply grounding, calibration and verification methods, used to validate mathematical models, to methods of estimating relative abundance. To illustrate how this might be done, we consider and evaluate the widely applied passive tracking index (PTI) methodology. Using published data, we examine the rationality of PTI methodology, how conceptually animal activity and abundance are related and how alternative methods are subject to similar biases or produce …

Is Anthropogenic Cougar Mortality Compensated By Changes In Natural Mortality In Utah? Insight From Long-Term Studies, Michael L. Wolfe, David N. Koons, David C. Stoner, Patricia Terletzky, Eric M. Gese, David M. Choate, Lise M. Aubry

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding the interplay between exploitation and natural mortality is essential to guiding sustainable conservation of wildlife. Exploitation of carnivores by humans has long been thought to result in compensatory reductions of natural mortality among survivors. If rates of human exploitation exceed natural mortality, however, such actions will ‘add’ to overall mortality and could imperil the sustainability of such actions. We applied competing risk analyses to >/= 16 years of data for heavily harvested and semi-protected cougar populations in Utah to test the additive and compensatory mortality hypotheses, while accounting for parameter uncertainty. We additionally tested for presence of the two …

Predator-Induced Renesting And Reproductive Effort In Indigo Buntings: More Work For Less Pay?, Dana L. Morris, John Faaborg, Brian E. Washburn, Joshua J. Millspaugh

United States Department of Agriculture Wildlife Services: Staff Publications

Renesting after nest predation is ultimately an adaptive response to increase productivity in birds. However, renesting also increases reproductive effort to replace lost clutches. We investigated the consequences of this increased reproductive effort by determining whether renesting in female indigo buntings (Passerina cyanea) is associated with a decline in body condition (size-corrected mass) and haematocrit and an increase in stress hormones and whether renesting or maternal body condition is associated with a decline in productivity (clutch size, nestling body condition). Next, because a consequence of multiple renesting attempts is a prolonged breeding season and later timing, we predicted …

Effects Of Mountain Beaver Management And Thinning On 15-Year-Old Douglas Fir Growth And Survival, Dan L. Campbell, Richard M. Engeman, James P. Farley

United States Department of Agriculture Wildlife Services: Staff Publications

We examined 4-year growth of 15-year-old damaged and undamaged Douglas fir (Pseudotsuga menzesii) after integrating temporary population reductions of mountain beaver (Aplodontia rufa) with thinning in a pre-commercial hand-planted plantation in western Washington. Five treatment combinations were considered: (1) trapping mountain beavers in an unthinned area, (2) trapping before thinning to 65 trees/ha (160 trees/ac), (3) no trapping and thinning to 65 trees/ha, (4) no trapping and thinning to 146 trees/ha (360 trees/ac), and (5) no trapping and no thinning. Removal of ≥90 % of mountain beavers temporarily reduced mountain beaver activity whether the stand was unthinned or thinned. Diameter …

Avian Bornaviruses In North American Gulls, Jianhua Guo, Ian Tizard, John A. Baroch, H L. Shivaprasad, Susan L. Payne

United States Department of Agriculture Wildlife Services: Staff Publications

Avian bornaviruses, recently described members of the family Bornaviridae, have been isolated from captive parrots and passerines as well as wild waterfowl in which they may cause lethal neurologic disease. We report detection of avian bornavirus RNA in the brains of apparently healthy gulls. We tested 439 gull brain samples from 18 states, primarily in the northeastern US, using a reversetranscriptase PCR assay with primers designed to detect a conserved region of the bornavirus M gene. Nine birds yielded a PCR product of appropriate size. Sequencing of PCR products indicated that the virus was closely related to aquatic bird bornavirus …

Review Of The 2012 Epizootic Hemorrhagic Disease Outbreak In Domestic Ruminants In The United States, G Stevens, B Mccluskey, A. King, E O'Hearn, G Mayr

United States Department of Agriculture Wildlife Services: Staff Publications

An unusually large number of cases of Epizootic hemorrhagic disease (EHD) were observed in United States cattle and white-tailed deer in the summer and fall of 2012. USDA APHIS Veterinary Services area offices were asked to report on foreign animal disease investigations and state diagnostic laboratory submissions which resulted in a diagnosis of EHD based on positive PCR results. EHD was reported in the following species: cattle (129 herds), captive white-tailed deer (65 herds), bison (8 herds), yak (6 herds), elk (1 herd), and sheep (1 flock). A majority of the cases in cattle and bison were found in Nebraska, …

The Cost Of Canine Rabies On Four Continents, A. M. Anderson, S. A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

We estimated the economic impacts of canine rabies in Latin America, Africa and Asia. Direct and indirect costs of rabies post-exposure prophylaxis, dog vaccination and control, rabies diagnostic testing and cattle mortality-related costs were accounted for. The number of human deaths was updated from previous estimates based on population growth, and the costs associated with the risk of human mortality were incorporated. We accounted for uncertainty associated with the parameter estimates using a Monte Carlo simulation and estimated that the global burden of canine rabies is approximately $124 billion annually. This result illustrates the potential benefits that could be realized …

Carnivore Incidents With U.S. Civil Aircraft, Alexander R. Crain, Jerrold L. Belant, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife incidents with aircraft are of concern in the United States as they pose a risk to human safety and economic losses for the aviation industry. Most previous research on wildlife-aircraft incidents has emphasized birds, bats, and ungulates. We queried the Federal Aviation Administration’s National Wildlife Strike Database from 1990 to 2012 to characterize carnivore incidents with U.S. civil aircraft. We found 1016 carnivore incidents with aircraft representing at least 16 species, with coyotes (n = 404) being the species most frequently struck. California and Texas had the most reported incidents and incidents were most likely to occur at …

Influence Of Simulated Double-Crested Cormorant, Phalacrocorax Auritus, Predation On Multiple-Batch Production Of Channel Catfish,Ictalurus Punctatus, Brian S. Dorr, Carole R. Engle

United States Department of Agriculture Wildlife Services: Staff Publications

The double-crested cormorant, Phalacrocorax auritus, is considered the primary depredating bird species on commercially produced channel catfish, Ictalurus punctatus, in the southeastern USA. We simulated different levels of cormorant predation on losses at harvest and economic effects on channel catfish production in a multiple-batch cropping system. We observed significant (P<0.05) declines in catfish production at increasing levels of cormorant predation in this study. This decline was mitigated by increased individual growth of catfish at higher predation rates (i.e., lower catfish densities). This mitigating effect produced a non-linear relationship with total kg of catfish harvested per pond resulting in a non-linear incremental increase in breakeven price related to predation. Costs of production ($/kg) increased with increasing predation levels up to very high levels of predation with a cumulative maximum increase in breakeven price of $0.143/kg. These results indicate that losses at harvest due to cormorant predation occur immediately but are mitigated in part by compensatory growth of individual catfish. Losses due to cormorant predation in multi-batch systems can be considerable, but there is not a 1:1 relationship between losses and kg of catfish harvested due to compensatory factors.

Spatially Explicit Modeling Of Blackbird Abundance In The Prairie Pothole Region, Greg M. Forcey, Wayne E. Thogmartin, George M. Linz, Patrick C. Mckann, Shawn M. Crimmins

United States Department of Agriculture Wildlife Services: Staff Publications

Knowledge of factors influencing animal abundance is important to wildlife biologists developing management plans. This is especially true for economically important species such as blackbirds (Icteridae), which cause more than $100 million in crop damages annually in the United States. Using data from the North American Breeding Bird Survey, the National Land Cover Dataset, and the National Climatic Data Center, we modeled effects of regional environmental variables on relative abundance of 3 blackbird species (red-winged blackbird, Agelaius phoeniceus; yellow-headed blackbird, Xanthocephalus xanthocephalus; common grackle, Quiscalus quiscula) in the Prairie Pothole Region of the central United States. We …

Molecular Assessment Of Translocation And Management Of An Endangered Subspecies Of White-Tailed Deer (Odocoileus Virginianus), Matthew W. Hopken, Tod M. Lum, Paul M. Meyers, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Translocations are an effectual management strategy for the reestablishment and reconnection of endangered populations and species. However, knowledge about the evolution and ecology of the populations and species of interest are critical so that informed decisions can be made about source populations and reestablishment areas. We employed 614 base pairs of the mitochondrial control region and 15 microsatellite loci to investigate genetic variation, contemporary connectivity, and interspecific hybridization in the two remaining populations of the endangered Columbian white-tailed deer (Odocoileus virginianus leucurus) through comparisons with the closest subspecies, O. v. ochrourus. Our data revealed the dubious taxonomic …

Capillaria Hepatica Infection In Black Rats (Rattus Rattus) On Diego Garcia, British Indian Ocean Territory, Are R. Berentsen, Scott Vogt, Antenor N. Guzman, Daniel S. Vice, William C. Pitt, Aaron B. Shiels, Terry R. Spraker

United States Department of Agriculture Wildlife Services: Staff Publications

Rats (Rattus spp.) are among the most damaging invasive species worldwide. The accidental introduction of rats has caused significant detriment to native flora and fauna, crops, structures, and human livelihoods. Rats are vectors of disease and carriers of various zoonotic parasites. Capillaria hepatica (syn. Callodium hepaticum) is a parasitic nematode found primarily in rodents but is known to infect over 140 mammal species, including human beings and several species of domestic animals. In this case study, the presence of C. hepatica infection in black rats on Diego Garcia, British Indian Ocean Territory, is reported. Liver samples from …

Shifting Perceptions Of Risk And Reward: Dynamic Selection For Human Development By Black Bears In The Western United States, H. E. Johnson, S. W. Breck, S. Baruch-Mordo, D. L. Lewis, C. W. Lackey, K. R. Wilson, J. Broderick, J. S. Mao, J. P. Beckmann

United States Department of Agriculture Wildlife Services: Staff Publications

As landscapes across the globe experience increasing human development, it is critical to identify the behavioral responses of wildlife to this change given associated shifts in resource availability and risk from human activity. This is particularly important for large carnivores as their interactions with people are often a source of conflict, which can impede conservation efforts and require extensive management. To examine the adaptations of a large carnivore to benefits and risks associated with human development we investigated black bear behavior in three systems in the western United States. Our objectives were to (1) identify temporal patterns of selection for …

Potential For Great Egrets (Ardea Alba) To Transmit A Virulent Strain Of Aeromonas Hydrophila Among Channel Catfish (Ictalurus Punctatus) Culture Ponds, Madison M. Jubirt, Larry A. Hanson, Katie C. Hanson-Dorr, Lorelei Ford, Scott Lemmons, Paul Fioranelli, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Aeromonas hydrophila is a gram-negative, rod-shaped, facultative, anaerobic bacterium that is ubiquitous in freshwater and slightly brackish aquatic environments and infects fish, humans, reptiles, and birds. Recent severe outbreaks of disease in commercial channel catfish (Ictalurus punctatus) aquaculture ponds have been associated with a highly virulent A. hydrophila strain (VAH), which is genetically distinct from less-virulent strains. The epidemiology of this disease has not been determined. Given that A. hydrophila infects birds, we hypothesized that fish-eating birds may serve as a reservoir for VAH and spread the pathogen by flying to uninfected ponds. Great Egrets (Ardea alba …

Influenza A Virus H5–Specific Antibodies In Mute Swans (Cygnus Olor) In The Usa, Whitney M. Kistler, David E. Stallknecht, Camille Lebarbenchon, Kerri Pedersen, David R. Marks, Randy Mickley, Thomas J. Deliberto, Michael J. Yabsley

United States Department of Agriculture Wildlife Services: Staff Publications

The use of serologic assays for influenza A virus (IAV) surveillance in wild birds has increased because of the availability of commercial enzyme-linked immunosorbent assays (ELISAs). Recently, an H5-specific blocking ELISA (bELISA) was shown to reliably detect H5-specific antibodies to low- and highpathogenic H5 viruses in experimentally infected waterfowl. Mute Swans (Cygnus olor) were frequently associated with highly pathogenic H5N1 outbreaks in Europe and may have a similar role if highly pathogenic H5N1 is introduced into North America. We measured the prevalence of antibodies to the nucleoprotein and H5 protein in Mute Swans using three serologic assays. We …

Chemical Repellents Appear Non-Useful For Eliciting Exit Of Brown Tree Snakes From Cargo, Fred Kraus, Randal S. Stahl, William Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The brown tree snake (Boiga irregularis) is invasive in Guam, has imposed ecological and economic problems there, and threatens to be dispersed via cargo and vehicles to other islands in the Pacific, where it could be expected to inflict similar damages. Prevention of inadvertent snake export currently relies on cargo inspection and suppression of snake populations around ports, which are expensive and incompletely reliable. Hence, there has long been interest in developing additional tools to preclude snakes leaving in cargo, and fumigation with essential oils has been suggested for this role. We tested gaseous or aerosol deliveries of …

Deer Response To Exclusion From Stored Cattle Feed In Michigan, Usa, Michael J. Lavelle, Henry Campa Iii, Kyle Ledoux, Patrick J. Ryan, Justin W. Fischer, Kim M. Pepin, Chad R. Blass, Michael P. Glow, Scott E. Hygnstrom, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Disease and damage from white-tailed deer (Odocoileus virginianus) continually threaten the livelihood of agricultural producers and the economy in the United States, as well as challenge state and federal wildlife managers. Threats can be partially addressed by excluding free-ranging deer from livestock-related resources. Throughout the year, use of stored livestock feed by deer in northern Lower Michigan (MI), USA fluctuates, though their presence is relatively consistent. Since 2008, use of livestock areas and resources by deer has been reduced through intensive efforts by livestock producers in cooperation with state and federal agencies. These efforts focused on excluding deer …

Limitations Of Population Suppression For Protecting Crops From Bird Depredation: A Review, George M. Linz, Enrique H. Bucher, Sonia B. Canavelli, Ethel Rodriguez, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Blackbirds (Icterinae) in North America, and dickcissels (Spiza americana Gmelin), eared doves (Zenaida auriculata Des Murs), and monk parakeets (Myiopsitta monachus Boddaert) in South America can cause serious economic damage to grain crops. Farmers frequently advocate lethal bird damage abatement measures based on the perceived need to take immediate action to avoid serious economic losses. In comparison, wildlife managers must make informed decisions based on a multitude of factors, including local, state, and national environmental laws, administrative restrictions, logistics, costs, expected outcome, and cultural considerations related to wildlife stewardship. In this paper, we focus on practicality, environmental …

West Nile Virus Antibody Decay Rate In Free-Ranging Birds, Eileen M. Mckee, Edward D. Walker, Tavis K. Anderson, Uriel D. Kitron, Jeffrey D. Brawn, Bethany L. Krebs, Christina Newman, Marilyn O. Ruiz, Rebecca S. Levine, Mary E. Carrington, Robert G. Mclean, Tony L. Goldberg, Gabriel L. Hamer

United States Department of Agriculture Wildlife Services: Staff Publications

Antibody duration, following a humoral immune response to West Nile virus (WNV) infection, is poorly understood in free-ranging avian hosts. Quantifying antibody decay rate is important for interpreting serologic results and for understanding the potential for birds to serorevert and become susceptible again. We sampled free-ranging birds in Chicago, Illinois, US, from 2005 to 2011 and Atlanta, Georgia, US, from 2010 to 2012 to examine the dynamics of antibody decay following natural WNV infection. Using serial dilutions in a blocking enzymelinked immunosorbent assay, we quantified WNV antibody titer in repeated blood samples from individual birds over time. We quantified a …

Knowledge, Attitudes And Practices Regarding Rabies And Exposure To Bats In Two Rural Communities In Guatemala, David Moran, Patricia Juliao, Danilo Alvarez, Kim A. Lindblade, James A. Ellison, Amy T. Gilbert, Brett Petersen, Charles Rupprecht, Sergio Recuenco

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Rabies is a fatal encephalitis caused by rabies virus, of the genus Lyssavirus. The principal reservoir for rabies in Latin America is the common vampire bat (Desmodus rotundus), which feeds routinely on the blood of cattle, and when livestock are scarce, may prey on other mammals, including humans. Although rabies is endemic in common vampire bat populations in Guatemala, there is limited research on the extent of exposure to bats among human populations living near bat refuges.

Results: A random sample of 270 of 473 households (57%) in two communities located within 2 Km of …

Novel Paramyxoviruses In Bats From Sub-Saharan Africa, 2007–2012, Marinda Mortlock, Ivan V. Kuzmin, Jacqueline Weyer, Amy T. Gilbert, Bernard Agwanda, Charles E. Rupprecht, Louis H. Nel, Teresa Kearney, Jean M. Malekani, Wanda Markotter

United States Department of Agriculture Wildlife Services: Staff Publications

As part of a larger survey for detection of pathogens among wildlife in sub-Saharan Africa conducted during 2007–2012, multiple diverse paramyxovirus sequences were detected in renal tissues of bats. Phylogenetic analysis supports the presence of at least 2 major viral lineages and suggests that paramyxoviruses are strongly associated with several bat genera.

Modeling The Economic Impacts Of Double-Crested Cormorant Damage To A Recreational Fishery, Stephanie A. Shwiff, Katy N. Kirkpatrick, Travis L. Devault, Steven S. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

The double-crested cormorant (Phalacrocorax auritus) has undergone a significant range expansion in the Great Lakes area of the United States since the 1970s, negatively impacting native fish populations and sport fisheries. Effective management of wildlife requires policies and practices that quantify their economic impacts, which is often complicated by multiplier effects in the regional economy. This analysis estimates the potential direct and regional economic impacts of the cormorant to a recreational fishery. We estimated that the potential economic loss was on average $5 million to $66 million annually, as well as 66 to 929 job-years in the region …

Progressive Accumulation Of The Abnormal Conformer Of The Prion Protein And Spongiform Encephalopathy In The Obex Of Nonsymptomatic And Symptomatic Rocky Mountain Elk (Cervus Elaphus Nelsoni) With Chronic Wasting Disease, Terry R. Spraker, Thomas Gidlewski, Jenny G. Powers, Tracy Nichols, Aru Balachandran, Bruce Cummings, Margaret A. Wild, Kurt C. Vercauteren, Katherine I. O’Rourke

United States Department of Agriculture Wildlife Services: Staff Publications

The purpose of our study was to describe the progressive accumulation of the abnormal conformer of the prion protein (PrP^CWD) and spongiform degeneration in a single section of brain stem in Rocky Mountain elk (Cervus elaphus nelsoni) with chronic wasting disease (CWD). A section of obex from 85 CWD-positive elk was scored using the presence and abundance of PrP^CWD immunoreactivity and spongiform degeneration in 10 nuclear regions and the presence and abundance of PrP^CWD in 10 axonal tracts, the subependymal area of the fourth ventricle, and the thin subpial astrocytic layer (glial limitans). Data …