Medicine and Health Sciences Commons^™

Reduced Intestinal Colonization Of Adult Beef Cattle By Escherichia Coli O157:H7 Tir Deletion And Nalidixic-Acid-Resistant Mutants Lacking Flagellar Expression, Gustavo Bretschneider, Emil M. Berberov, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

The importance of the Escherichia coli O157:H7 translocated intimin receptor (Tir) protein in intestinal colonization and the effect of infection with Tir⁺ strains on protection against subsequent challenge was studied in adult beef cattle. Cattle were orally inoculated (C1) with a Shiga toxin-2⁺+ E. coli O157:H7 strain that was Tir⁺ or Tir^-, and 42 days later were re-challenged (C2) with the nalidixic acid (Nal) ^R parent strain to test whether prior infection had any effect on fecal shedding. During the first 14 days post-C1, the Nal^S wildtype (WT) strain was shed at significantly …

Porcine Intestinal Epithelial Cell Lines As A New In Vitro Model For Studying Adherence And Pathogenesis Of Enterotoxigenic Escherichia Coli, Seung Y. Koh, Sajan George, Volker Brozel, Rodney A. Moxley, David H. Francis, Radhey Kaushik

School of Veterinary and Biomedical Sciences: Faculty Publications

Enterotoxigenic Escherichia coli (ETEC) infections result in large economic losses in the swine industry worldwide. The organism causes diarrhea by adhering to and colonizing enterocytes in the small intestines. While much progress has been made in understanding the pathogenesis of ETEC, no homologous intestinal epithelial cultures suitable for studying porcine ETEC pathogenesis have been described prior to this report. In the current study, we investigated the adherence of various porcine ETEC strains to two porcine (IPEC-1 and IPEC-J2) and one human (INT-407) small intestinal epithelial cell lines. Each cell line was assessed for its ability to support the adherence of …

Stable Cell Lines Expressing High Levels Of The Herpes Simplex Virus Type 1 Lat Are Refractory To Caspase 3 Activation And Dna Laddering Following Cold Shock Induced Apoptosis, Dale Carpenter, Chinhui Hsiang, Donald J. Brown, Ling Jin, Nelson Osorio, Lbachir Benmohamed, Clinton J. Jones, Steven L. Wechsler

School of Veterinary and Biomedical Sciences: Faculty Publications

The herpes simplex virus type 1 (HSV-1) latency associated transcript (LAT) gene’s anti-apoptosis activity plays a central, but not fully elucidated, role in enhancing the virus’s reactivation phenotype. In transient transfection experiments, LAT increases cell survival following an apoptotic insult in the absence of other HSV-1 genes. However, the high background of untransfected cells has made it difficult to demonstrate that LAT inhibits specific apoptotic factors such as caspases. Here we report that, in mouse neuroblastoma cell lines (C1300) stably expressing high levels of LAT, cold shock induced apoptosis was blocked as judged by increased survival, protection against DNA fragmentation …

Light-Evoked Calcium Responses Of Isolated Melanopsin- Expressing Retinal Ganglion Cells, Andrew T. E. Hartwick, Jayne R. Bramley, Jianing Yu, Kelly T. Stevens, Charles N. Allen, William H. Baldridge, Patricia J. Sollars, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

A small number (<2%) of mammalian retinal ganglion cells express the photopigment melanopsin and are intrinsically photosensitive (ipRGCs). Light depolarizes ipRGCs and increases intracellular calcium levels ( [Ca²⁺]_i ) but the signaling cascades underlying these responses have yet to be elucidated. To facilitate physiological studies on these rare photoreceptors, highly enriched ipRGC cultures from neonatal rats were generated using anti-melanopsin-mediated plate adhesion (immunopanning). This novel approach enabled experiments on isolated ipRGCs, eliminating the potential confounding influence of rod/cone-driven input. Light induced a rise in [Ca²⁺]_i (monitored using fura-2 imaging) in the immunopanned ipRGCs and the source of this Ca²⁺ signal was investigated. The Ca²⁺ responses were inhibited by 2-aminoethoxydiphenyl borate, SKF-96365 (1–2-(4-methoxyphenyl)-2-[3-(4-methoxyphenyl)propoxy]ethyl-1H-imidazole), flufenamic acid, …

2006 Michigan Dairy Farm Business Analysis Summary, Eric Wittenberg, Christopher Wolf

Michigan Bovine Tuberculosis Bibliography and Database

This report summarizes the financial and production records of 139 dairy farms from throughout Michigan in 2006. To be included, the farms must have produced at least 50 percent of gross cash farm income from milk and dairy animal sales. The records came from Michigan State University’s TelFarm project and the Farm Credit Service system in Michigan. The values were pooled into averages for reporting purposes. The farms are larger than would be the average of all dairy farms in Michigan. While considerable variation in the data exists, average values are reported in the summary tables and discussion that follows.

Differences In Virulence Among Escherichia Coli O157:H7 Strains Isolated From Humans During Disease Outbreaks And From Healthy Cattle, Diane R. Baker, Rodney A. Moxley, Mike B. Steele, Jeffrey T. Lejeune, Jane Christopher-Hennings, Ding-Geng Chen, Philip R. Hardwidge, David H. Francis

School of Veterinary and Biomedical Sciences: Faculty Publications

Escherichia coli O157:H7 causes life-threatening outbreaks of diarrhea, hemorrhagic colitis, and hemolyticuremic syndrome in humans and significant economic loss in agriculture and could be a potential agent of bioterrorism. Although the prevalence of E. coli O157:H7 in cattle and other species with which humans have frequent contact is high, human infections are relatively uncommon, despite a low infectious dose. A plausible explanation for the low disease incidence is the possibility that not all strains are virulent in humans. If there are substantial differences in virulence among strains in nature, then human disease may select for high virulence. We used a …

Enhancement Of Efficacy Of Prrsv Vaccines By Altering The Glycosylation Pattern Of Viral Glycoproteins, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

PRRSV, the causative agent of PRRS is of major economic significance to the pork industry in the USA and around the world. Current commercial vaccine does not provide adequate protection against PRRSV outbreaks. Therefore, there is an urgent need for development of more efficacious vaccine to combat PRRS. Our previous studies have suggested that (i) induction of neutralizing antibody response is an important correlate of evaluating the efficacy of a vaccine; (ii) neutralizing antibodies can be enhanced by hypoglycosylation of the major surface glycoprotein (GP5). While it is known that GP5 plays a prominent role in neutralizing antibody induction, it …

Otk18, A Zinc-Finger Protein, Regulates Human Immunodeficiency Virus Type 1 Long Terminal Repeat Through Two Distinct Regulatory Regions, Masahide Horiba, Lindsey B. Martinez, James L. Buescher, Sinji Sato, Jenae Limoges, Yunquan Jiang, Clinton J. Jones, Tsuneya Ikezu

School of Veterinary and Biomedical Sciences: Faculty Publications

It has previously been shown by our laboratory that OTK18, a human immunodeficiency virus (HIV)-inducible zinc-finger protein, reduces progeny-virion production in infected human macrophages. OTK18 antiviral activity is mediated through suppression of Tat-induced HIV-1 long terminal repeat (LTR) promoter activity. Through the use of LTR scanning mutant vectors, the specific regions responsible for OTK18-mediated LTR suppression have been defined. Two different LTR regions were identifi ed as potential OTK18-binding sites by an enhanced DNA–transcription factor ELISA system; the negative-regulatory element (NRE) at –255/–238 and the Ets-binding site (EBS) at –150/–139 in the LTR. In addition, deletion of the EBS in …

Isotype-Specific Antibody Responses Against Escherichia Coli O157:H7 Locus Of Enterocyte Effacement Proteins In Adult Beef Cattle Following Experimental Infection, G. Bretschneider, E. M. Berberov, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Escherichia coli O157:H7 is an important food-borne pathogen and cause of hemorrhagic colitis and hemolytic uremic syndrome in humans. Cattle are an important reservoir of E. coli O157:H7, in which the organism colonizes the intestinal tract and is shed in the feces. Vaccination of cattle has significant potential as a pre-harvest intervention strategy for E. coli O157:H7; however, basic information about the bovine immune responses to important bacterial colonization factors resulting from infection has not been reported. The serum and fecal IgG and IgA antibody responses of adult cattle to E. coli O157:H7 intimin, translocated intimin receptor (Tir), E. coli …

Low Molecular Weight Protein Tyrosine Phosphatase (Lmw-Ptp) And Its Possible Physiological Functions Of Redox Signaling In The Eye Lens, Kuiyi Xing, Ashraf Raza, Stefan Lofgren, M. Rohan Fernando, Ye-Shih Ho, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Low molecular weight protein tyrosine phosphatase (LMW-PTP) was cloned from human lens epithelial B3 cells (HLE B3) and the recombinant enzyme was purified to homogeneity. The pure enzyme reacted positively with anti-LMW-PTP antibody, displayed tyrosine-specific phosphatase activity and was extremely sensitive to H2O2. The inactivated LMW-PTP could be regenerated by thioltransferase (TTase)/GSH system as demonstrated by both activity assay and by mass spectrometry (MS). The MS study also showed that an intramolecular disulfide bond was formed between C13 and C18 at the active site, and was reduced by the TTase/GSH system. The putative role of LMW-PTP in regulating platelet derived …

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

Other Publications in Zoonotics and Wildlife Disease

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

Other Publications in Zoonotics and Wildlife Disease

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%), …

The Infected Cell Protein 0 Encoded By Bovine Herpesvirus 1 (Bicp0) Induces Degradation Of Interferon Response Factor 3 And, Consequently, Inhibits Beta Interferon Promoter Activity, Kazima Saira, You Zhou, Clinton J. Jones

School of Veterinary and Biomedical Sciences: Faculty Publications

The ICP0 protein (bICP0) encoded by bovine herpesvirus 1 is the major viral regulatory protein because it stimulates all viral promoters and, consequently, productive infection. Like other ICP0 analogues encoded by Alphaherpesvirinae subfamily members, bICP0 contains a zinc RING finger near its amino terminus that is necessary for activating transcription, regulating subcellular localization, and inhibiting interferon-dependent transcription. In this study, we discovered that sequences near the C terminus, and the zinc RING finger, are necessary for inhibiting the human beta interferon (IFN- β) promoter. In contrast to herpes simplex virus type 1-encoded ICP0, bICP0 reduces interferon response factor 3 (IRF3), …

Localization Of Period 1 Mrna In The Ruminant Oocyte And Investigations Of Its Role In Ovarian Function, R. A. Cushman, M. F. Allan, S. A. Jones, Gary P. Rupp, S. E. Echternkamp

School of Veterinary and Biomedical Sciences: Faculty Publications

The clock gene Period 1 (Per1) may be a prolificacy gene, because it localized to the mouse oocyte and Per1-null drosophila shed fewer eggs. Because Per1 mapped to a region of mouse chromosome 11 syntenic to bovine chromosome 19 where a quantitative trait loci (QTL) for ovulation rate existed, we hypothesized that Per1 influenced folliculogenesis and ovulation rate in ruminants. Ovarian cortex was collected at slaughter on days 5, 12, 15, 17, and 20 after estrus for real-time RT-PCR evaluation of Per1mRNAexpression in Dorset (n = 18), Romanov (n = 10), Romanov/Dorset (n = 21), and Composite …

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

Other Publications in Zoonotics and Wildlife Disease

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

Other Publications in Zoonotics and Wildlife Disease

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 …

Michigan Bovine Tuberculosis Eradication Project: 2007 Activities Report

Michigan Bovine Tuberculosis Bibliography and Database

Bovine tuberculosis (TB) is an infectious disease that is close to being eradicated in the United States, but still poses a significant risk to domestic livestock, wildlife, companion animals, and humans throughout the world. The Michigan Bovine TB Eradication Project involves a multi-agency team of experts from the Michigan departments of Agriculture, Natural Resources and Community Health, Michigan State University, and the US Department of Agriculture.

Managing Bovine Tuberculosis In White-Tailed Deer In Northwestern Minnesota: A 2007 Progress Report, Michelle Carstensen, David Pauly, Michael Doncarlos, Lou Cornicelli

Michigan Bovine Tuberculosis Bibliography and Database

Bovine tuberculosis (TB), first discovered in 2005, has now been found in 11 cattle operations in northwestern Minnesota. To date, all of the infected cattle herds have been depopulated and the Board of Animal Health (BAH) has continued an investigation of herds in the area as well as conducted a statewide surveillance effort. The strain has been identified as one that is consistent with bovine TB found in cattle in the southwestern United States and Mexico. In November 2007, the Minnesota Department of Natural Resources (MNDNR) conducted bovine TB surveillance of hunter-harvested white-tailed deer (Odocoileus virginianus) within a …

Research Strategies To Reduce Bovine Tuberculosis Transmission From Wildlife To Cattle, Are R. Brentensen, Mike R. Dunbar, Robert G. Mclean

Michigan Bovine Tuberculosis Bibliography and Database

Bovine tuberculosis (bTB) is a zoonotic disease caused by Mycobaterium bovis, and is transmissible to humans, wildlife and domestic livestock. In the northern Lower Peninsula of Michigan, white-tailed deer ( Odocoileus virginianus) serve as a reservoir for the disease and pose a significant threat to domestic cattle and captive cervids. Scientists at USDA, APHIS, Wildlife Services, National Wildlife Research Center have designed a variety of laboratory and field studies aimed at reducing or eliminating bTB infection in cattle by interrupting the transmission of the disease from wildlife reservoirs. These strategies include reducing bTB in deer by delivery of …

Risk Factors Associated With The Prevalence Of Tuberculosis-Like Lesions In Fenced Wild Boar And Red Deer In South Central Spain, Joaquin Vicente, Ursula Hofle, Joseba M. Garrido, Isabel G. Fernandez-De-Mera, Pelayo Acevedo, Ramon Juste, Marta Barral, Christian Gortazar

Michigan Bovine Tuberculosis Bibliography and Database

In recent decades the management of large game mammals has become increasingly intensive in south central Spain (SCS), resulting in complex epidemiological scenarios for disease maintenance, and has probably impeded schemes to eradicate tuberculosis (TB) in domestic livestock. We conducted an analysis of risk factors which investigated associations between the pattern of tuberculosis-like lesions (TBL) in wild boar (Sus scrofa) and red deer (Cervus elaphus) across 19 hunting estates from SCS and an extensive set of variables related to game management, land use and habitat structure. The aggregation of wild boar at artificial watering sites was …

The Birth Of A Wild Ass (Equus Hemionus Khur) In India’S Little Rann Of Kutch, Gertrud Neumann-Denzau

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The birth of a wild ass was completely described and photographed in the wild for the first time. It happened in the daytime, in the open desert, and in the vicinity of other wild asses. The mother isolated her foal afterwards for an entire day. After birthing she drove away her male yearling, which did not join her any longer from this moment on.

Research Strategies Of The National Wildlife Research Center To Control Bovine Tuberculosis In Wildlife In Michigan, Usa, A. R. Berentsen, M. R. Dunbary, R. G. Mclean

Michigan Bovine Tuberculosis Bibliography and Database

Bovine tuberculosis (bTB) is a zoonotic disease caused by Mycobaterium bovis and is transmissible to humans, wildlife, and domestic livestock. In the United Kingdom, the suspected wildlife reservoir of bTB is the badger (Meles meles) (HUTCHINGS and HARRIS, 1997), and in New Zealand, the culprit is the brush-tailed possum (Trichosurus vulpecula) (MORRIS et al., 1994). In northern Michigan, USA, bovine tuberculosis is endemic in white-tailed deer (Odocoileus virginianus). In 1975 a hunter-killed white-tailed deer in Alpena County, Michigan, USA, was tested positive for bTB. Subsequent surveillance by the Michigan Department of Natural Resources (MDNR) …

Vaccination Of White-Tailed Deer (Odocoileus Virginianus) With Mycobacterium Bovis Bacillus Calmette Guerin, M. V. Palmer, T. C. Thacker, W. R. Waters

Michigan Bovine Tuberculosis Bibliography and Database

Wildlife reservoirs of Mycobacterium bovis represent serious obstacles to the eradication of tuberculosis in domestic livestock. In Michigan, USA tuberculous white-tailed deer transmit M. bovis to cattle. One approach in dealing with this wildlife reservoir is to vaccinate deer in order to interrupt the cycle of deer to deer and deer to cattle transmission. Thirty-one white-tailed deer were assigned to one of three groups; 2 SC doses of 10⁷ CFU of M. bovis BCG (n = 11); 1 SC dose of 10⁷ CFU of M. bovis BCG (n = 10); or unvaccinated deer (n = 10). …

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

Other Publications in Zoonotics and Wildlife Disease

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; found worldwide in birds; and infect a variety of avian species.

Differential Engagement Of Tim-1 During Activation Can Positively Or Negatively Costimulate T Cell Expansion And Effector Function, Vijay K. Kuchroo, Sheng Xiao, Nader Najafian, Jay Reddy, Monica Albin, Chen Zhu, Eric Jensen, Jaimie Imitola, Thomas Korn, Ana C. Anderson, Zheng Zhang, Cristina Gutierrez, Thomas Moll, Raymond A. Sobel, Dale T. Umetsu, Hideo Yagita, Hisaya Akiba, Terry Strom, Mohamed H. Sayegh, Rosemarie H. Dekruyff, Samia J. Khoury

School of Veterinary and Biomedical Sciences: Faculty Publications

It has been suggested that T cell immunoglobulin mucin (Tim)-1 expressed on T cells serves to positively costimulate T cell responses. However, crosslinking of Tim-1 by its ligand Tim-4 resulted in either activation or inhibition of T cell responses, thus raising the issue of whether Tim-1 can have a dual function as a costimulator. To resolve this issue, we tested a series of monoclonal antibodies specifi c for Tim-1 and identifi ed two antibodies that showed opposite functional effects. One anti–Tim-1 antibody increased the frequency of antigen-specifi c T cells, the production of the proinfl ammatory cytokines IFN-γ and IL-17, …

Chlorophacinone Baiting For Belding’S Ground Squirrels, Craig A. Ramey, George H. Matschke, Richard M. Engeman

USDA Wildlife Services: Staff Publications

The efficacy of using 0.01% chlorophacinone on steam-rolled oat (SRO) groats applied in CA alfalfa by spot-baiting/hand baiting around burrow entrances (~11.5 g) to control free-ranging Belding's ground squirrels (Spermophilus beldingi) were compared in 6 randomly assigned square treatment units (TUs). Four TUs were given the rodenticide and 2 treated with placebo bait. Each TU was a 0.4 ha square surrounded by a similarly treated 5.5 ha square buffer zone. Baits were applied on May 13 and re-applied, on May 20 and May 22, after 7 days of un-forecasted cool wet weather greatly reduced their above ground activity. Pesticide (EPA …

Department Of Veterinary And Biomedical Sciences 2007 Annual Report

Veterinary and Biomedical Sciences -- Department Information and History

The first class of twenty· five Nebraska students began their DVM degree program at the University of Nebraska-Lincoln. The new program provides for students from Nebraska to complete their first two years of the professional school at UNL. The second two years of training will be completed at the College of Veterinary Medicine, Iowa State University. Under the agreement, the students will pay Iowa State resident tuition rates all four years.

To prepare for the new program, an anatomy teaching laboratory, classroom and microbiology laboratory were develop by renovating space in the Animal Science Complex. New faculty members hired to …

Coyotes As Sentinels For Monitoring Bovine Tuberculosis Prevalence In White-Tailed Deer, Todd Atwood, Kurt C. Vercauteren, Thomas Deliberto, Holly Smith, Justin Stevenson

Michigan Bovine Tuberculosis Bibliography and Database

Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), is endemic in free-ranging white-tailed deer (Odocoileus virginianus) in 5 counties (Alcona, Alpena, Montmorency, Oscoda, and Presque Isle) in the northeastern Lower Peninsula of Michigan, USA. The presence of a wildlife reservoir of tuberculosis in Michigan and the incidence of bTB in cattle (Bos taurus) resulted in Michigan losing its bTB accredited-free status. Subsequent wildlife surveillance programs identified relatively high disease prevalence in coyotes (Canis latrans), generating interest in their potential to serve as a sentinel species to detect bTB prevalence in white-tailed deer. …

Protostrongylid Parasites And Pneumonia In Captive And Wild Thinhorn Sheep (Ovis Dalli), Emily J. Jenkins, A. M. Veitch, Susan J. Kutz, T. K. Bollinger, J. M. Chirino-Trejo, B. T. Elkin, K. H. West, Eric P. Hoberg, L. Polley

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

We describe health significance of protostrongylid parasites (Parelaphostrongylus odocoilei and Protostrongylus stilesi) and other respiratory pathogens in more than 50 naturally infected Dall’s sheep (Ovis dalli dalli) from the Mackenzie Mountains, Northwest Territories (1998–2002) as well as in three Stone’s sheep (O. d. stonei) experimentally infected with P. odocoilei (2000–2002). Histological lesions in the brain and distribution of P. odocoilei in the muscles of experimentally and naturally infected sheep were consistent with a previously hypothesized ‘‘central nervous system to muscle’’ pattern of migration for P. odocoilei. Dimensions of granulomas associated with eggs of …