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Leptospirosis In The Azores: The Rodent Connection, Gary W. Witmer, Hernani Martins, Lidia Flor

United States Department of Agriculture Wildlife Services: Staff Publications

The Azores are Portuguese islands in the North Atlantic Ocean. The culture is very agrarian with a large cattle industry. Unfortunately, there is a chronic leptospirosis problem within the people, livestock, companion animals, and wildlife of the Azores. Introduced rodents play a significant role as maintenance hosts of this disease. We review the situation and make recommendations for reducing the occurrence and hazard of leptospirosis in the Azores. Areas addressed include the need for a better understanding of the epidemiology of the disease and the role of rodents, development of an effective rodent control program, improvements in farm practices and …

West Nile Virus And Wildlife Health, Peter P. Marra, Sean M. Griffing, Robert G. Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

The West Nile Virus and Wildlife Health Workshop, hosted by the Smithsonian Institution, National Audubon Society, U.S. Geological Survey, and U.S. Department of Agriculture, was held February 5–7, 2003, at the Smithsonian Environmental Research Center in Edgewater, Maryland. The event was attended by more than 100 scientists, who heard 29 speakers and participated in strategy discussions during the 2-day meeting. The main focus of the conference was the present and future impact of West Nile virus on wildlife populations. Talks and discussions emphasized how basic research, public health, and land management can contribute to our understanding of the disease’s impact …

Prevalence Of Antibodies To Neospora Caninum, Sarcocystis Neurona, And Toxoplasma Gondii In Wild Horses From Central Wyoming, J. P. Dubey, S.M. Mitchell, J.K. Morrow, J.C. Rhyan, L.M. Stewart, D.E. Granstrom, S. Romand, P. Thulliez, W.J. Saville, D.S. Lindsay

United States Department of Agriculture Wildlife Services: Staff Publications

Sarcocystis neurona, Neospora caninum, N. hughesi, and Toxoplasma gondii are 4 related coccidians considered to be associated with encephalomyelitis in horses. The source of infection for N. hughesi is unknown, whereas opossums, dogs, and cats are the definitive hosts for S. neurona, N. caninum, and T. gondii, respectively. Seroprevalence of these coccidians in 276 wild horses from central Wyoming outside the known range of the opossum (Didelphis virginiana) was determined. Antibodies to T. gondii were found only in 1 of 276 horses tested with the modified agglutination test using 1: 25, 1:50, …

The Emergence Of Major Avian Diseases In North America: West Nile Virus And More, Robert G. Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

Some major diseases of wild birds have emerged dramatically in North America recently due in part to the rapid global movement of animals and pathogens and major changes in the size, quality, and continuity of natural habitats. These diseases include invasive pathogens, emergence of new disease agents or syndromes, and reemergence of some established diseases. A prominent example is West Nile virus that invaded North America, became easily established, and has expanded throughout the continent within 4 years. A number of factors have influenced the frequency of occurrence, the variety of species affected, and the geographical extent of these emergent …

Oral Rabies Vaccination: Reducing Economic Uncertainty Via Response Surface Analysis, Ray T. Sterner, Matthew A. Kling, Stephanie A. Shwiff, Dennis Slate

United States Department of Agriculture Wildlife Services: Staff Publications

Economic uncertainty surrounds the distribution of Raboral V-RG7 as an oral rabies vaccine (ORV) bait for the containment or elimination of raccoon-variant rabies in the United States. This paper describes a costs-savings model of ORV. It also describes Excel XP7 code that was prepared to compute potential net savings (NS) and benefit-cost ratios (BCRs) associated with Raboral V-RG7 bait distributions. Currently, baits and bait distributions are relatively expensive; individual baits are produced at a cost of $1.27 for federal use and typically dispensed at >75 baits/km2. Distribution is estimated at $8.62/km², $15.80/km², and $33.30/km² for …

Mycobacterial Diseases In Wildlife, Gary W. Witmer, Thomas Deliberto, Kurt C. Vercauteren, Peter Butchko

United States Department of Agriculture Wildlife Services: Staff Publications

Mycobacterium infections occur in numerous wildlife species worldwide and this bacterial genus can also cause disease in humans and livestock. Two Mycobacterium species and one subspecies that infect wildlife are important from a wildlife damage management perspective. Mycobacterium avium, avian tuberculosis, is a ubiquitous and cosmopolitan disease of wild and domestic birds. Wild and domestic ruminants are host to M. avium paratuberculosis, also known as Johne’s disease. Finally, Mycobaterium bovis, bovine tuberculosis, is primarily associated with domestic and wild bovines and ungulates, but also infects many other species of mammals. Eradicating these diseases from wildlife populations is …

A Review Of Pathogens Of Agricultural And Human Health Interest Found In Blackbirds, Larry Clark, Robert G. Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

Because of their numbers and close association with humans and agriculture. the role of blackbirds in disease transmission has been of concern. Unfortunately fear systematic and quantitative studies have been carried out that bear on this issue. We review the extant literature on zoonoses and pathogens of agricultural concern where there is documented evidence for the involvement of blackbirds and starlings. It is clear that blackbirds can exacerbate levels of risk for failures in agricultural biosecurity and human health. To what degree these levels of risk are raised is largely unknown and should be the focus of future studies because …

A Review Of Pathogens Of Agricultural And Human Health Interest Found In Canada Geese, Larry Clark

United States Department of Agriculture Wildlife Services: Staff Publications

The roles that waterfowl in general, and Canada geese in particular, have in the dissemination and transmission of viral and bacterial diseases of human or agricultural importance are covered in this review. In addition to the biological information about the etiology of the disease, economic impacts and zoonotic potential of viral and bacterial pathogens are considered. In most cases existing evidence suggests the importance of waterfowl in disease dissemination and transmission, however, definitive data are often lacking, indicating the need for more directed studies before quantitative risk assessments can be made. Finally, a brief assessment of management options is considered.

Feral Swine---Are They A Disease Threat To Livestock In The United States?, Gary W. Witmer, Robert B. Sanders, Arnold C. Taft

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine populations provide both benefits and liabilities to citizens of the United States. Their expanding range and increasing densities, however, have raised concern over the adverse environmental and agricultural effects and the increased risk of disease transmission between feral swine and livestock. We discuss the role of feral swine in the transmission of wildlife diseases and, in particular, in diseases of national significance to the livestock industry. We also discuss available management tools and strategies for reducing feral swine populations, minimizing damage or disease occurrences and eradicating populations when deemed appropriate. Finally, we note areas of research that may …

Territorial Defense By Coyotes (Canis Latrans) In Yellowstone National Park, Wyoming: Who, How, Where, When, And Why, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Territorial defense and maintenance are an important facet of the social ecology of most carnivore species. From January 1991 to June 1993, we observed 54 coyotes (Canis latrans) for 2507 h in Yellowstone National Park, Wyoming, during which we observed 112 instances of territory defense. The identity of the coyotes involved in challenging and evicting intruding animals was known. Alpha coyotes were most likely to be involved in territorial evictions of intruding animals, followed by beta individuals; pups participated little in territory defense. Coyotes evicting intruders generally had a numerical advantage when challenging the intruders. Territory-defense rates were …

Disease Emergence In Birds: Challenges For The Twenty-First Century, Milton Friend, Robert G. Mclean, F. Joshua Dein

United States Department of Agriculture Wildlife Services: Staff Publications

Finch (Carpodacus mexicanus) conjunctivitis is an example of the rapid geographic spread that can result from disease emergence in naive populations. That event was neither novel nor transient relative to its occurrence or effects. Disease emergence and reemergence are hallmarks of the latter part of the twentieth century (Center for Disease Control 1994, Levins et al. 1994, DaSilva and Laccarino 1999, Gratz 1999). Current examples involving domestic animals include the problems in Europe with bovine spongiform encephalopathy (BSE, or ‘‘mad cow disease’’) (Brown 2001) and foot-and-mouth disease (FMD) (Kitching 1999). Human health has been affected by diseases caused …

"References" For Carnivore Conservation, John L. Gittleman, Stephan M. Funk, David Macdonald, Robert K. Wayne, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

119-page bibliography of works cited in in CARNIVORE CONSERVATION, edited by John L. Gittleman, Stephan M. Funk, David Macdonald, and Robert K. Wayne, Cambridge University Press, 2001.

Includes approximately 2,000 items.

Serological Responses Of Coyotes To Two Commercial Rabies Vaccines, Frederick F. Knowlton, Marianna Roetto, Deborah Briggs

United States Department of Agriculture Wildlife Services: Staff Publications

Between August 1993 and September 1994 we documented serological responses of coyotes (Canis latrans) vaccinated with two commercial rabies vaccines licensed for use in domestic dogs. Serologic responses were documented by testing for rabies virus neutralizing antibodies with the rapid fluorescent focus inhibition test (RFFIT) at 30, 90, 180, 270, and 365 days post-vaccination. All coyotes vaccinated with Imrab 3^® (Rhone-Merieux, Inc.), and 75% of those vaccinated with Dura-Rab 3^® (Immunovet, Inc.) seroconverted, as evidenced by the presence of antirabies antibody titers ≥1:5 in one or more of the five post-vaccination samples. The percent of coyotes …

Demonstration Of Tritrichomonas Foetus In The External Genitalia And Of Specific Antibodies In Preputial Secretions Of Naturally Infected Bulls, J. C. Rhyan, K. L. Wilson, B. Wagner, M. L. Anderson, R. H. Bondurant, D. E. Burgess, G. K. Mutwiri, L. B. Corbeil

United States Department of Agriculture Wildlife Services: Staff Publications

Portions of penis and prepuce were collected from 24 bulls with current or recent Tritrichomonas foetus infection. Epididymides were collected from seven of the bulls, and seminal vesicles and prostate were collected from four. Following immunohistochemical staining with two monoclonal antibodies (34.7C4.4 and TF1.15) prepared against T. foetus surface antigens, trichomonads were identified in sections from 15 of the bulls. Organisms were most often located in penile crypts in the midshaft and caudal regions and less often in preputial crypts. Trichomonads were not observed in sections from other genitalia or in subepithelial tissue. T. foetus antigen, however, was present in …

Epidemic Leptospirosis Associated With Pulmonary Hemorrhage—Nicaragua, 1995, Rosalie T. Trevejo, José G. Rigau-Pérez, David A. Ashford, Emily M. Mcclure, Carlos Jarquín-González, Juan J. Amador, José O. De Los Reyes, Alcides Gonzalez, Sherif R. Zaki, Wun-Ju Shieh, Robert G. Mclean, Roger S. Nasci, Robbin S. Weyant, Carole A. Bolin, Sandra L. Bragg, Bradley A. Perkins, Richard A. Spiegel

United States Department of Agriculture Wildlife Services: Staff Publications

In October 1995, epidemic “hemorrhagic fever,” without jaundice or renal manifestations, was reported in rural Nicaragua following heavy flooding; 2259 residents were evaluated for nonmalarial febrile illnesses (cumulative incidence, 6.1%) and 15 (0.7%) died with pulmonary hemorrhage. A case-control study found that case-patients were more likely than controls to have ever walked in creeks (matched odds ratio [MOR], 15.0; 95% confidence interval [CI], 1.7–132.3), have household rodents (MOR, 10.4; 95% CI, 1.1–97.1), or own dogs with titers ≥ 400 to Leptospira species (MOR, 23.4; 95% CI, 3.6–`). Twenty-six of 51 case-patients had serologic or postmortem evidence of acute leptospirosis. Leptospira …