Veterinary Infectious Diseases Commons^™

Ovine Progressive Pneumonia Provirus Levels Are Unaffected By The Prion 171r Allele In An Idaho Sheep Flock, Robert D. Harrington, Lynn M. Herrmann-Hoesing, Stephen N. White, Katherine I. O'Rourke, Donald P. Knowles

Zoonotics and Wildlife Disease: Publications

Selective breeding of sheep for arginine (R) at prion gene (PRNP) codon 171 confers resistance to classical scrapie. However, other effects of 171R selection are uncertain. Ovine progressive pneumonia/Maedi-Visna virus (OPPV) may infect up to 66% of a flock thus any affect of 171R selection on OPPV susceptibility or disease progression could have major impact on the sheep industry. Hypotheses that the PRNP 171R allele is 1) associated with the presence of OPPV provirus and 2) associated with higher provirus levels were tested in an Idaho ewe flock. OPPV provirus was found in 226 of 358 …

Validation Of Use Of Rectoanal Mucosa-Associated Lymphoid Tissue For Immunohistochemical Diagnosis Of Chronic Wasting Disease In White-Tailed Deer (Odocoileus Virginianus), Delwyn Keane, Daniel Barr, Rebecca Osborn, Julie Langenberg, Katherine I. O'Rourke, David Schneider, Phillip Bochsler

Zoonotics and Wildlife Disease: Publications

The examination of rectoanal mucosa-associated lymphoid tissue (RAMALT) biopsy specimens for the diagnosis of transmissible spongiform encephalopathies has been described in sheep, elk, and small numbers of mule and white-tailed deer. Previous sample numbers have been too small to validate examination of this type of tissue as a viable antemortem diagnostic test. In this study, we examined RAMALT collected postmortem from 76 white-tailed deer removed from a farm in Wisconsin known to be affected by chronic wasting disease (CWD) and from 210 free-ranging white-tailed deer harvested from an area in Wisconsin where the overall prevalence of CWD among the deer …

Blood Chimerism Confounds Genetic Relative Susceptibility Testing For Classical Scrapie In Sheep, David A. Schneider, Ahmed Tibary, Terje Taudsepp, Pranab J. Das, Katherine I. O'Rourke

Zoonotics and Wildlife Disease: Publications

Classical scrapie disease is a transmissible spongiform encephalopathy of sheep that is enzootic in the United States. Susceptibility of sheep to classical scrapie is linked to single nucleotide polymorphisms in the prion protein gene (PRNP), forming the basis for genetic testing strategies used by national efforts to eradicate scrapie. Such efforts are occasionally hampered by inconclusive results stemming from the detection of ‘‘complex’’ genotypes. Naturally occurring cases of ovine chimerism are thought to account for some of these instances. In the current report, 4 naturally occurring ovine chimeras are documented through cytogenetic and molecular analyses. All 4 of these sheep …

Nor98 Scrapie Identified In The United States, Christie M. Loiacono, Bruce V. Thomsen, S. Mark Hall, Matti Kiupel, Diane Sutton, Katherine I. O'Rourke, Bradd Barr, Lucy Anthenill, Delwyn Keane

Zoonotics and Wildlife Disease: Publications

A distinct strain of scrapie identified in sheep of Norway in 1998 has since been identified in numerous countries throughout Europe. The disease is known as Nor98 or Nor98-like scrapie, among other names. Distinctions between classic scrapie and Nor98 scrapie are made based on histopathology and immunodiagnostic results. There are also differences in the epidemiology, typical signalment, and likelihood of clinical signs being observed. In addition, sheep that have genotypes associated with resistance to classic scrapie are not spared from Nor98 disease. The various differences between classic and Nor98 scrapie have been consistently reported in the vast majority of cases …

Bovine Viral Diarrhea Virus Multiorgan Infection In Two White-Tailed Deer In Southeastern South Dakota, Christopher C.L. Chase, Lyle J. Braun, Pamela Leslie-Steen, Tanya Graham, Dale Miskimins, Julia F. Ridpath

Veterinary and Biomedical Sciences Faculty Publications

The susceptibility of wild ruminants, especially cervids, to bovine viral diarrhea virus (BVDV) has remained an enigma. Two white-tailed deer (Odocoileus virginianus) were submitted to the Animal Disease Research and Diagnostic Laboratory (ADRDL) in the fall of 2003 by the South Dakota Game Fish and Parks for chronic wasting disease (CWD) testing. Both animals were CWD negative. The animals were necropsied and histopathology, viral antigen detection, and virus isolation were performed. A noncytopathic (NCP) BVDV was isolated from the lungs and several other tissues of both animals. Formalin-fixed ear notches from both animals were positive for BVDV antigen by immunohistochemistry. …

Sheep Updates 2008 - Contents, Department Of Food And Agriculture, Western Australia

Sheep Updates

No abstract provided.

Tetanus And Rabies Eradication In Pakistan; A Mission Not Impossible, Mohammad Wasay, Ismail A. Khatri, Naseem Salahuddin

Department of Medicine

No abstract provided.

Brown Dog Tick: Vector For Rocky Mountain Spotted Fever, Craig Levy

Zoonotics and Wildlife Disease: Publications

The brown dog tick, Rhipicephalus sanguineus (Acari: Ixodidae), feeds primarily on dogs and until recently was not known to vector Rocky Mountain spotted fever (RMSF). In 2003–2004, fourteen cases of RMSF in humans occurred in eastern Arizona in the absence of known vectors, the Rocky Mountain wood tick, Dermacentor andersoni, and American dog tick, Dermacentor variabilis. However, health officials found brown dog ticks to be very abundant in areas associated with human cases, and the Centers for Disease Control and Prevention (CDC) implicated that the brown dog tick was responsible for transmitting RMSF. Brown dog ticks occur throughout the United …

Ecological Factors Associated With West Nile Virus Transmission, Northeastern United States, Heidi E. Brown, James E. Childs, Maria A. Diuk-Wasser, Durland Fish

Zoonotics and Wildlife Disease: Publications

Since 1999, West Nile virus (WNV) disease has affected the northeastern United States. To describe the spatial epidemiology and identify risk factors for disease incidence, we analyzed 8 years (1999–2006) of county-based human WNV disease surveillance data. Among the 56.6 million residents in 8 northeastern states sharing primary enzootic vectors, we found 977 cases. We controlled for population density and potential bias from surveillance and spatial proximity. Analyses demonstrated significant spatial spreading from 1999 through 2004 (p2 = 0.16). A significant trend was apparent among increasingly urban counties; county quartiles with the least (0.75 cases/100,000 residents) than counties with the …

Myenteric Neurons Of The Ileum That Express Somatostatin Are A Target Of Prion Neuroinvasion In An Alimentary Model Of Sheep Scrapie, David A. Schneider, Huijun Yan, Lindsay M. Fry, Janet Alverson, Stephen N. White, Katherine I. O'Rourke

Zoonotics and Wildlife Disease: Publications

Neuroinvasion of the enteric nervous system by prions is an important step in dissemination to the brain, yet very little is known about the basic process of enteric neuroinvasion. Using an alimentary model of neonatal disease transmission, neuroinvasion by scrapie prions in the ileum of lambs was detected by immunohistochemical staining for the disease-associated form of the prion protein, PrP^Sc. Odds ratios (OR) were determined for the frequency of PrP^Sc staining within enteric somata categorized by plexus location (myenteric, submucosal) and neurochemical staining (PGP 9.5, neural nitric oxide synthase, somatostatin, substance P, and vasoactive intestinal polypeptide). PrP …

Prion Gene (Prnp) Haplotype Variation In United States Goat Breeds, Stephen N. White, Lynn Herrmann-Hoesing, Katherine I. O'Rourke, Daniel Waldron, Joan Rowe, Janet Alverson

Zoonotics and Wildlife Disease: Publications

Scrapie eradication efforts cost 18 million dollars annually in the United States and rely heavily upon PRNP genotyping of sheep. Genetic resistance might reduce goat scrapie and limit the risk of goats serving as a scrapie reservoir, so PRNP coding sequences were examined from 446 goats of 10 breeds, 8 of which had not been previously examined at PRNP. The 10 observed alleles were all related to one of two central haplotypes by a single amino acid substitution. At least five of these alleles (M142, R143, S146, H154, and K222) have been associated with increased incubation time or decreased …

A Species Barrier Limits Transmission Of Chronic Wasting Disease To Mink (Mustela Vison), Robert D. Harrington, Timothy V. Baszler, Katherine I. O'Rourke, David A. Schneider, Terry R. Spraker, H. Denny Liggitt, Donald P. Knowles

Zoonotics and Wildlife Disease: Publications

Transmissible mink encephalopathy (TME) occurs as sporadic outbreaks associated with ingestion of feed presumably contaminated with some type of prion disease. Mink lack a species barrier to primary oral challenge with bovine spongiform encephalopathy, whereas they have a barrier to such challenge with scrapie. We investigated whether mink have a species barrier to chronic wasting disease (CWD) by performing primary intracerebral (IC) and primary oral challenge with CWD-positive elk brain. Primary IC challenge resulted in clinical disease in two of eight mink at 31–33 months incubation. Affected mink had spongiform vacuolation and astrocytosis within the central nervous system and immunoreactivity …

Scrapie Resistance In Arq Sheep, W. W. Laegreid, M. L. Clawson, M. P. Heaton, B. T. Green, Katherine I. O'Rourke, D. P. Knowles

Zoonotics and Wildlife Disease: Publications

Variation in the ovine prion protein amino acid sequence influences scrapie progression, with sheep homozygous for A¹³⁶R¹⁵⁴Q¹⁷¹ considered susceptible. This study examined the association of survival time of scrapie-exposed ARQ sheep with variation elsewhere in the ovine prion gene. Four single nucleotide polymorphism alleles were associated with prolonged survival. One nonsynonymous allele (T112) was associated with an additional 687 days of survival for scrapie-exposed sheep compared to M112 sheep (odds ratio, 42.5; P = 0.00014). The only two sheep homozygous for T112 (TARQ) did not develop scrapie, suggesting that the allelic effect may be additive. …

A Collaborative Canadian–United Kingdom Evaluation Of An Immunohistochemistry Protocol To Diagnose Bovine Spongiform Encephalopathy, Lisa Manning, Katherine I. O'Rourke, Donald P. Knowles, Sarah A. Marsh, Yvonne I. Spencer, Estella Moffat, Gerald A. H. Wells, Stefanie Czub

Zoonotics and Wildlife Disease: Publications

Collaboration was established in 2001 to evaluate a commercially available immunohistochemistry assay kit for the detection of bovine spongiform encephalopathy (BSE) disease–associated prion protein in formic acid–treated formalin-fixed samples of bovine brain. The kit protocol was evaluated at the National Centre for Foreign Animal Diseases (Winnipeg, Canada) and the Veterinary Laboratories Agency (Weybridge, U.K.). The U.K. laboratory provided paraffin-embedded blocks of brainstem (medulla oblongata at the level of the obex) from 100 positive cases defined by clinical signs and histopathology, and 100 clinically suspect but BSE-negative samples defined by histopathology and immunohistochemistry with anti-PrP monoclonal antibody R145. The Canadian laboratory …

Experimental Transmission Of Chronic Wasting Disease (Cwd) Of Elk (Cervus Elaphus Nelsoni), White-Tailed Deer (Odocoileus Virginianus), And Mule Deer (Odocoileus Hemionus Hemionus) To White-Tailed Deer By Intracerebral Route, A. N. Hamir, J. A. Richt, J. M. Miller, R. A. Kunkle, S. M. Hall, E. M. Nicholson, Katherine I. O'Rourke, J. J. Greenlee, E. S. Williams

Zoonotics and Wildlife Disease: Publications

To compare clinical and pathologic findings of chronic wasting disease (CWD) in a natural host, 3 groups (n = 5) of white-tailed deer (WTD) fawns were intracerebrally inoculated with a CWD prion of WTD, mule deer, or elk origin. Three other uninoculated fawns served as controls. Approximately 10 months postinoculation (MPI), 1 deer from each of the 3 inoculated groups was necropsied and their tissues were examined for lesions of spongiform encephalopathy (SE) and for the presence of abnormal prion protein (PrP^d) by immunohistochemistry (IHC) and Western blot (WB). The remaining deer were allowed to live until …

Chronic Wasting Disease In A Wisconsin White-Tailed Deer Farm, Delwyn P. Keane, Daniel J. Barr, Phillip N. Bochsler, S. Mark Hall, Thomas Gidlewski, Katherine I. O'Rourke, Terry R. Spraker, Michael D. Samuel

Zoonotics and Wildlife Disease: Publications

In September 2002, chronic wasting disease (CWD), a prion disorder of captive and wild cervids, was diagnosed in a white-tailed deer (Odocoileus virginianus) from a captive farm in Wisconsin. The facility was subsequently quarantined, and in January 2006 the remaining 76 deer were depopulated. Sixty animals (79%) were found to be positive by immunohistochemical staining for the abnormal prion protein (PrP^CWD) in at least one tissue; the prevalence of positive staining was high even in young deer. Although none of the deer displayed clinical signs suggestive of CWD at depopulation, 49 deer had considerable accumulation of …

Small-Ruminant Lentivirus Enhances PrpSc Accumulation In Cultured Sheep Microglial Cells, James B. Stanton, Donald P. Knowles, Katherine I. O'Rourke, Lynn M. Herrmann-Hoesing, Bruce A. Mathison, Timothy V. Baszler

Zoonotics and Wildlife Disease: Publications

Sheep scrapie is the prototypical transmissible spongiform encephalopathy (prion disease), which has a fundamental pathogenesis involving conversion of normal cellular prion protein (PrP^C [C superscript stands for cellular]) to disease-associated prion protein (PrP^Sc [Sc superscript stands for sheep scrapie]). Sheep microglial cell cultures, derived from a prnp 136VV/171QQ near-term fetal brain, were developed to study sheep scrapie in the natural host and to investigate potential cofactors in the prion conversion process. Two culture systems, a primary cell culture and a cell line transformed with the large T antigen of simian virus 40, were developed, and both were identified …

Febrile Response And Decrease In Circulating Lymphocytes Following Acute Infection Of White-Tailed Deer Fawns With Either A Bvdv1 Or A Bvdv2 Strain, Julia F. Ridpath, C. Scott Mark, Christopher C.L. Chase, Alanson C. Ridpath, John D. Neill

Veterinary and Biomedical Sciences Faculty Publications

Although commonly associated with infection in cattle, bovine viral diarrhea viruses (BVDV) also replicate in many domestic and wildlife species, including cervids. Bovine viral diarrhea viruses have been isolated from a number of cervids, including mule deer (Odocoileus hemionus), European roe deer (Capreolus capreolus), red deer (Cervus elaphus), white-tailed deer (Odocoileus virginianus), and mouse deer (Tragulus javanicus), but little information is available regarding clinical presentation and progression of infection in these species. In preliminary studies of experimental infection of deer with BVDV, researchers noted seroconversion but no clinical signs. In this study, we infected white-tailed deer fawns that were negative …

Sheep Updates 2007 - Part 3, Andrew Ritchie, Edward Riggall, James Hall, Gus Rose, Johan Greeff, John Young, M. Alchin, M. Young, T. Johnson, John Lucy, Martin Staines, Tim Wiley, Rob Grima, Sandra Prosser, Matt Ryan, Geoff Moore, Tony Albertsen, Phil Barrett-Lennard, George Woolston, John Titerington, Sarah Knight, Brianna Peake

Sheep Updates

This session covers seven papers from different authors:

PROFITABILITY

1. Benchmarking demonstrates both the potential and realised productivity gains in the sheep and wool industry, Andrew Ritchie, Edward Riggall and James Hall, ICON Agriculture, Darkan

2. Improving sheep genetics will increase farm profitability, Gus Rose, Johan Greeff Department of Agriculture and Food Western Australia, John Young Farming Systems Analysis Service, WA

3. Meat, Merinos and making money in WA Pastoral Zone, M. Alchin, M. Young and T. Johnson, Department of Agriculture and Food Western Australia,

GRAZING

4. Nitrogen - farmers' friend or foe? John Lucy and Martin Staines, Department …

Sheep Updates 2007 - Part 5, Bindi Murray, John Karlsson, Johan Greeff, Carolina Viñoles Gil, B. L. Paganoni, K. M. M. Glover, J. T. B. Milton, G. B. Martin, Hugh Dove, Bill Mckiernan, John Wilkins, Paul Greenwood, Linda Cafe

Sheep Updates

This session covers six papers from different authors:

GENETIC IMPROVEMENT

1. Breech Strike Resistance: Selecting for resistance traits reduces breech strike, Bindi Murray, John Karlsson, Johan Greeff, Department of Agriculture and Food, Western Australia

2. Breeding Merino Sheep for Worm Resistance increases profit in a Mediterranean Environment, John Karlsson and Johan Greeff Department of Agriculture and Food, Western Australia

FEEDING

3. Embryo lasses were not increased when Merino ewes that had lost weight were supplemented with lupins, C. Viñoles Gil, B.L. Paganoni, K.M.M. Glover, J.T.B. Milton & G.B. Martin, School of Animal Biology, Faculty of Natural and Agricultural Sciences, …

Sheep Updates 2007 - Contents, Department Of Agriculture And Food, Western Australia

Sheep Updates

No abstract provided.

Spatial And Temporal Patterns Of Enzootic Raccoon Rabies Adjusted For Multiple Covariates, Sergio Recuenco, Millicent Eidson, Martin Kulldorff, Glen Johnson, Bryan Cherry

Zoonotics and Wildlife Disease: Publications

Background: With the objective of identifying spatial and temporal patterns of enzootic raccoon variant rabies, a spatial scan statistic was utilized to search for significant terrestrial rabies clusters by year in New York State in 1997–2003. Cluster analyses were unadjusted for other factors, adjusted for covariates, and adjusted for covariates and large scale geographic variation (LSGV). Adjustments were intended to identify the unusual aggregations of cases given the expected distribution based on the observed locations.

Results: Statistically significant clusters were identified particularly in the Albany, Finger Lakes, and South Hudson areas. The clusters were generally persistent in the Albany area, …

Potential Cost Savings With Terrestrial Rabies Control, Sergio Recuenco, Bryan Cherry, Millicent Eidson

Zoonotics and Wildlife Disease: Publications

Background: The cost-benefit of raccoon rabies control strategies such as oral rabies vaccination (ORV) are under evaluation. As an initial quantification of the potential cost savings for a control program, the collection of selected rabies cost data was pilot tested for five counties in New York State (NYS) in a three-year period.

Methods: Rabies costs reported to NYS from the study counties were computerized and linked to a human rabies exposure database. Consolidated costs by county and year were averaged and compared.

Results: Reported rabies-associated costs for all rabies variants totalled $2.1 million, for human rabies postexposure prophylaxes (PEP) (90.9%), …

An Hsus Report: Human Health Implications Of U.S. Live Bird Markets In The Spread Of Avian Influenza, The Humane Society Of The United States

Impact of Animal Agriculture

After millions of years of existing as a harmless infection of aquatic birds, some strains of avian flu have developed the ability to mutate into highly pathogenic forms that may not only be deadly for birds, but potentially more dangerous for humans as well. Experts from the World Health Organization, the World Organization for Animal Health, and the Food and Agriculture Organization of the United Nations have joined leading scientists in implicating industrialized poultry production for providing fertile ground for the transformation of benign bird flu into highly pathogenic strains.

Live bird markets can be the conduit by which waterfowl …

Their Bugs Are Worse Than Their Bite: Emerging Infectious Disease And The Human-Animal Interface, Michael Greger

State of the Animals 2007

In the twenty-five years since that announcement, what we now know as AIDS has killed 20 million people (National AIDS Trust 2005). Where did the AIDS virus— and other emerging diseases, such as severe acute respiratory syndrome (SARS), Ebola, mad cow— come from?

The Human/Animal Interface: Emergence And Resurgence Of Zoonotic Infectious Diseases, Michael Greger

Transgenesis Collection

Emerging infectious diseases, most of which are considered zoonotic in origin, continue to exact a significant toll on society. The origins of major human infectious diseases are reviewed and the factors underlying disease emergence explored. Anthropogenic changes, largely in land use and agriculture, are implicated in the apparent increased frequency of emergence and reemergence of zoonoses in recent decades. Special emphasis is placed on the pathogen with likely the greatest zoonotic potential, influenzavirus A.

Hantavirus And Arenavirus Antibodies In Persons With Occupational Rodent Exposure, North America, Charles F. Fulhorst, Mary Louise Milazzo, Lori R. Armstrong, James E. Childs, Pierre E. Rollin, Rima Khabbaz, C.J. Peters, Thomas G G. Ksiazek

Zoonotics and Wildlife Disease: Publications

Rodents are the principal hosts of Sin Nombre virus, 4 other hantaviruses known to cause hantavirus pulmonary syndrome in North America, and the 3 North American arenaviruses. Serum samples from 757 persons who had worked with rodents in North America and handled neotomine or sigmodontine rodents were tested for antibodies against Sin Nombre virus, Whitewater Arroyo virus, Guanarito virus, and lymphocytic choriomeningitis virus. Antibodies against Sin Nombre virus were found in 4 persons, against Whitewater Arroyo virus or Guanarito virus in 2 persons, and against lymphocytic choriomeningitis virus in none. These results suggest that risk for infection with hantaviruses or …

Development Of An Assay To Determine Single Nucleotide Polymorphisms In The Prion Gene For The Genetic Diagnosis Of Relative Susceptibility To Classical Scrapie In Sheep, Mary Lynn Johnson, Jessica M. Evoniuk, Charles L. Stoltenow, Katherine I. O'Rourke, Dale A. Redmer

Zoonotics and Wildlife Disease: Publications

The objective of this study was to develop a reliable Taqman® 5' Nuclease Assay for genotyping sheep for scrapie susceptibility. The sheep prion gene contains 2 single nucleotide polymorphisms (SNPs) that may mediate resistance to classical scrapie, one at codon 136, alanine (A) or valine (V), and another at codon 171, arginine (R) or glutamine (Q). The R allele appears to confer resistance to classical scrapie, with the AA₁₃₆ RR₁₇₁ genotype the most resistant to scrapie and QR₁₇₁ only rarely infected in the US sheep population. The Assays by Design^SM protocol was used for development of …

Avian Influenza Vaccination: A Commentary Focusing On H5n1 High Pathogenicity Avian Influenza, Karen Burns Grogan, David A. Halvorson, Richard D. Slemons

Zoonotics and Wildlife Disease: Publications

Avian influenza (AI) is a viral disease of poultry, caused by influenzavirus A, classified in the family Orthomyxoviridiae. The influenza A viruses maintained in birds are commonly referred to as avian influenza viruses (AIVs). The AIVs are antigenically, genetically, and biologically diverse, are found worldwide in birds, and infect a variety of avian species.

Assessment Of Biosecurity Procedures To Prevent Bovine Viral Diarrhea Virus Cross Contamination, Rebecca Aden

The Journal of Undergraduate Research

Bovine viral diarrhea virus (BVDV) is a common virus among cattle, and there are many different strains of the virus. BVDV can cause mucosal disease in infected cattle. There are lab strains of BVDV used for testing, but there are also wild-type viruses that may develop within a herd or population. These wild-type strains can be dangerous due to cross contamination between herds. This project compares serum samples from two different herds on the basis of the antibody response to a wild-type virus isolated from a persistent infected animal in one of the herds. We tested for a possible cross …