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PennVet researcher awarded National Medal of Science

For his pioneering work in the field of genetics, Dr. Ralph L. Brinster, the Richard King Mellon Professor of Reproductive Physiology at the University of Pennsylvania School of Veterinary Medicine, has been awarded the 2010 National Medal of Science. It is the highest honor given by the United States government to scientists and engineers. He is the only veterinarian to have received such an award.

Dr. Brinster earned his VMD degree from the University of Pennsylvania School of Veterinary Medicine in 1960. He received his doctorate in 1964 from the Penn Vet Physiology Department. For his doctoral thesis, Dr. Brinster developed the first reliable in vitro culture system for early mammalian embryos. Today, this technique continues to form the foundation for research on mammalian embryos, including technologies such as transgenic engineering, embryonic stem cell therapy, human in vitro fertilization, mammalian cloning, and knockout engineering.

Using this method of embryo manipulation, he next worked out many aspects of the metabolism and development of eggs and early embryos. From there, Dr. Brinster became interested in modifying the development of animals and their germ lines, and he went on to become the first person to show that it was possible to colonize a mouse blastocyst with stem cells from older embryos. Moreover, Dr. Brinster first demonstrated that teratocarcinoma cells could combine with blastocyst cells to form adult chimeric mice, establishing the feasibility of this approach to change the genetic character of mice.

In the late ′70s, Dr. Brinster became interested in developing methods of introducing nucleic acids directly into an egg. He injected messenger RNA into mouse eggs in his pilot experiments and experienced some success. Later, Dr. Brinster began to wonder whether he could inject genes instead of mRNA into the eggs.

By 1981, he and Richard D. Palmiter, PhD, a professor of biochemistry at the University of Washington School of Medicine, were able to show for the first time that new genes could be introduced into the mammalian genome.

The two would go on to publish more than 100 papers together and provide the first proof of expression of transgenes, the first example of cancer arising from a transgene, and proof of the targeted integration of DNA by egg injection.

Dr. Brinster moved on to study male germ cell development. To do this, he needed a system of analysis similar to the one he had developed for eggs in the 1960s that would enable him to assess any experimental effects on spermatogonial stem cells, the male germ cell line stem cells. He hypothesized that if one were to take cells from a fertile testis and put them into the testis of an infertile mouse, the stem cells would be able to develop in the seminiferous tubules and generate donor-derived spermato-genesis. Dr. Brinster was proved right, and over the next few years, his laboratory determined many of the characteristics of spermatogonial stem cells, including their ability to be cryopreserved, which makes individual males biologically immortal. He and his colleagues also demonstrated that these stem cells could survive for months in vitro, which eventually led to culture techniques and the ability to modify the germ line with spermatogonial stem cells. Recently, Dr. Brinster's laboratory has extended their culture methods to farm animals and humans.

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Dr. Ralph L. Brinster is the first veterinarian to receive the medal since it was created in 1959. He received it from President Obama at an Oct. 21 ceremony at the White House. (Courtesy of the National Science & Technology Medals Foundation)

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

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Mice from Dr. Brinster's famous giant mouse experiment, in which the rat growth hormone gene was expressed in the liver of mice and which represented the first published example of transgenesis (Courtesy of Dr. Ralph L. Brinster)

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

Receiving the National Medal of Science, Dr. Brinster said, was a surprise and a great honor. He said he owes much of his success to the hard work and talent of his students, colleagues, and collaborators.

Two veterinarians awarded Institute of Medicine membership

Drs. Patricia A. Conrad of the University of California-Davis and Li-Huei Tsai of the Massachusetts Institute of Technology were among 65 individuals granted membership in the Institute of Medicine this past October. Fewer than 20 veterinarians are members of the IOM.

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Dr. Patricia A. Conrad

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

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Dr. Li-Huei Tsai

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

Dr. Conrad is widely recognized for her research on babesiosis and is credited with discovering two new species of babesial parasites infecting dogs and humans in the United States.

At the UC-Davis School of Veterinary Medicine, where Dr. Conrad is a professor in the Department of Pathology, Microbiology, and Immunology, she and her collaborators have helped improve the diagnosis and control of the parasite Neospora caninum, a common cause of abortion in dairy cattle.

In addition, Dr. Conrad is a co-director of the One Health Center of Expertise at the University of California Global Health Institute. There, she leads a team of researchers investigating the impact of fecal pathogen pollution in freshwater, marine, and terrestrial ecosystems on wildlife and human populations.

As director of the MIT Picower Institute for Learning and Memory, Dr. Tsai studies the pathologic mechanisms underlying neurologic disorders affecting learning and memory. She joined the faculty in the Department of Pathology at Harvard Medical School in 1994. Three years later, Dr. Tsai was named an investigator at Howard Hughes Medical Institute.

In 2006, Dr. Tsai was appointed professor in the Department of Brain and Cognitive Sciences at MIT, where she also joined the Picower Institute for Learning and Memory. Major research areas at the institute include neuropsychiatric disorders, autism, and Alzheimer's disease.

Pappaioanou resigns from AAVMC

Dr. Marguerite Pappaioanou announced Oct. 7 that she would resign as the executive director of the Association of American Veterinary Medical Colleges, effective Oct. 31. Starting in early 2012, she will go to work for DAI (Developmental Alternatives Inc.), where she will pursue initiatives in global development, public health, and one health.

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Dr. Marguerite Pappaioanou

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

AAVMC President Gerhardt Schurig announced that Dr. Bennie I. Osburn, the outgoing dean of the University of California-Davis School of Veterinary Medicine, would begin serving as interim director Nov. 1, 2011.

Dr. Pappaioanou began her position at the association Nov. 1, 2007. She oversaw the unveiling of the AAVMC's strategic plan in March 2009. The plan—the first in the association's 45-year history—lists the AAVMC's vision, mission, and values, in addition to the six goals that will determine the association's priorities and allocation of resources until 2014.

Concurrently, the AAVMC initiated the North American Veterinary Medical Education Consortium. Approximately 400 individuals from 150 groups participated in a series of three national meetings in 2010 to discuss core competencies needed by graduates, and to review and explore progress in developing new educational models for delivery of the veterinary curriculum.

Also during her tenure, Dr. Pappaioanou lobbied consistently on behalf of the AAVMC for passage of the Veterinary Public Health Workforce and Education Act, which would establish a competitive, multimillion-dollar grant program for veterinary colleges and other institutions offering graduate training in veterinary public health.

The AAVMC is currently searching for a new executive director.

Ross, Edinburgh name new deans

Dr. Elaine Watson will be the new dean of the Ross University School of Veterinary Medicine in St. Kitts, West Indies, and Dr. David J. Argyle succeeded her Nov. 1, 2011, as dean of the University of Edinburgh Royal (Dick) School of Veterinary Studies in Scotland. Dr. Watson will succeed Dr. David J. DeYoung, whose retirement was previously announced, on Feb. 1, 2011.

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Dr. Elaine Watson

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

A professor of animal reproduction, Dr. Watson was dean at Edinburgh since 2003. She led a $200 million capital development project to create a teaching facility on the Easter Bush Campus and gained $3.2 million in funding for the school's International Center in Animal Welfare Education.

Dr. Watson graduated from the University of Glasgow and has doctorates from Edinburgh and Bristol University. Her positions have included ones at the U.K. Ministry of Agriculture, Fisheries and Food and the University of Pennsylvania. In 1991, she returned to Edinburgh as head of reproduction and, in 1999, was awarded a personal chair in veterinary reproduction. She is a European specialist in equine reproduction and serves on editorial boards of three scientific journals.

Dr. Argyle graduated from the University of Glasgow and entered general practice. He earned his doctorate in oncology and immunology at Glasgow, then joined its Department of Veterinary Clinical Studies. In 2002, he became head of veterinary oncology at the University of Wisconsin-Madison. Returning to the U.K. in 2005, he was appointed to the William Dick Chair of Veterinary Clinical Studies at Edinburgh and has led its Veterinary Cancer Care Center since it opened in 2009.

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Dr. David J. Argyle

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

Dr. Argyle is a European specialist in veterinary oncology, a diplomate of the European College of Veterinary Internal Medicine–Companion Animals in Oncology, and scientific co-editor of the Journal of Veterinary and Comparative Oncology.

Center of Excellence focuses on dairy education

Four veterinary colleges will collaborate to develop and implement the National Center of Excellence in Dairy Production Medicine Education for Veterinarians. It was announced Oct. 4 that the veterinary colleges at the University of Georgia, University of Illinois, Kansas State University, and University of Minnesota received a grant for $700,000 from the Department of Agriculture's National Institute of Food and Agriculture for the project.

The grant is part of the Higher Education Challenge Grants Program, which makes awards on the basis of how well programs address local, regional, national, or international educational needs; whether they involve nontraditional or creative approaches that can serve as a model; and whether they encourage cooperation among universities and between academia and private business.

The Dairy Education Center, based in New Sweden, Minn., will serve as the primary location for the center of excellence's operations. Veterinary students from all four universities will live at the center during four two-week clinical rotations that focus on dairy health management, production systems, food safety, and food system security.

3-phase building project halfway through

The Virginia-Maryland Regional College of Veterinary Medicine is well on its way to completing the most substantial renovations and additions to its Blacksburg, Va., campus since the college opened in 1980.

The first building to be completed was the $10.5 million Infectious Disease Research Facility that is attached to the Veterinary Teaching Hospital and will offer select support services. Construction of the IDRF began in August 2010, and the building was expected to open for use no later than the end of November 2011.

This 16,000-square-foot building includes biosafety level-2 research facilities on the second floor and research support space on the first floor for the college's translational animal-model program focused on infectious disease and immunology.

The second major building project in the works is the addition of a 32,000-square-foot, $14 million Instructional Addition that will include space for approximately 35 new offices for faculty and enable the college to upgrade and renovate the existing offices. The basement level will contain a new suite of laboratories for teaching clinical techniques to third-year students. Support offices and flexible instructional space for breakout groups will occupy the ground level, and more faculty offices will occupy the second floor. Construction began in July, and the building is slated to open in August 2012.

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Construction on the Instructional Addition began this past July and should be completed in summer 2012.

Citation: American Journal of Veterinary Research 73, 1; 10.2460/ajvr.73.1.5

The final building envisioned as part of the college's major capital development initiative is the $93.9 million Translational Medicine Building. This complex will include a 20,000-square-foot addition to the VTH on the first floor as well as basic and clinical research laboratories on the second and third floors, to be shared with the College of Agriculture and Life Sciences and the College of Science at Virginia Tech. It will be a large addition, adding close to 100,000 square feet in all to the campus.

The Translational Medicine Building is on the university's capital outlay plan for the 2010–2012 biennium, but it will be another three to four years before construction starts on that building.

FDA funds food safety training program

A $1.3 million grant to develop a new food safety training program for government and industry has been awarded by the Food and Drug Administration to seven recipients, five of which have an associated veterinary school or college.

The grant, announced Oct. 5, funds the first year of a five-year agreement and is renewable for a total of $6.5 million. The grant is part of an FDA competitive grants program that aims to build an integrated national food safety system, as mandated by the U.S. Food Safety Modernization Act of 2011.

According to the law, signed by President Barack Obama in January 2011, Congress has provided the FDA with new regulatory authority to inspect farms. The FDA is also expected to hire thousands of new employees to fulfill this authority. These new hires will need to be trained; however, no coordinated training is currently offered by the federal, state, local, and tribal agencies that are tasked with ensuring food safety.

The following entities anticipate developing training programs to assist the FDA as the new regulations are written: Auburn University, the University of California-Davis, the International Food Protection Training Institute, Iowa State University, the National Environmental Health Association, North Carolina State University, and the University of Tennessee.

Together, they will help the FDA craft a national food safety curriculum that can be used to train agency and food industry personnel on standards for inspections, investigations, and laboratory testing as well as training and certification requirements, auditing criteria, and metrics for evaluating program performance. The training will involve not only manufactured foods, which have been a mainstay of FDA work, but also on-farm inspections. In addition, the project will create and improve course content to meet or exceed a national accreditation standard, with a focus on specialty produce crops, dairy, and laboratory operations.

Research awards conferred

The following individuals are winners of the 2011 Pfizer Animal Health Award for Research Excellence. The Pfizer award recognizes researchers whose innovative studies have advanced the scientific standing of veterinary medicine.

Pfizer Animal Health Award for Research Excellence

Valery A. Petrenko, PhD, Auburn University

Ian Gardner, BVSc, PhD, University of California-Davis

Shane Hentges, PhD, Colorado State University

Eric C. Ledbetter, DVM, Cornell University

Rowan J. Milner, BVSc, University of Florida

Robert M. Gogal Jr., DVM, University of Georgia

Levent Dirikolu, DVM, PhD, University of Illinois

Albert Jergens, DVM, PhD, Iowa State University

Juergen A. Richt, DVM, PhD, Kansas State University

Samithamby Jeyaseelan, DVM, PhD, Louisiana State University

Lorraine M. Sordillo, PhD, Michigan State University

Srinand Sreevatsan, BVSc, PhD, University of Minnesota

Andrea S. Varela-Stokes, DVM, PhD, Mississippi State University

Craig L. Franklin, DVM, PhD, University of Missouri-Columbia

Barbara Sherry, PhD, North Carolina State University

Wondwossen A. Gebreyes, DVM, PhD, The Ohio State University

Anthony Confer, DVM, PhD, Oklahoma State University

Claudia Hase, PhD, Oregon State University

Kendra K. Bence, PhD, University of Pennsylvania

Lynetta J. Freeman, DVM, Purdue University

David A. Brian, DVM, PhD, University of Tennessee

Jorg M. Steiner, DVM, PhD, Texas A&M University

Dominique Penninck, DVM, PhD, Tufts University

Berhanu Tameru, PhD, Tuskegee University

Lijuan Yuan, PhD, Virginia-Maryland Regional College of Veterinary Medicine

Michael Konkel, PhD, Washington State University

Victoria Voith, DVM, PhD, Western University of Health Sciences

David Vail, DVM, University of Wisconsin-Madison

Presidential order targets drug shortages

President Barack Obama signed an executive order Oct. 31 directing the Food and Drug Administration to take steps to attempt to reduce drug shortages, which have been arising mostly from supply disruptions.

In a report released that day, the FDA concluded that “drug shortages have been increasing in frequency and severity in recent years and adversely affecting patient care.”

Shortages of drugs that the FDA has approved for human use increased from 61 in 2005 to 178 in 2010, according to the report. Many of these drugs are in use in veterinary practice.

Analyzing 127 shortages of drugs that occurred during 2010 and 2011, the FDA found that sterile injectables accounted for 80 percent of the shortages. By therapeutic class, cancer drugs accounted for 28 percent of the shortages.

Major causes of drug shortages include quality problems at the drug manufacturing facility and other delays in manufacturing or shipping. Other causes include shortages of active pharmaceutical ingredients and business decisions to discontinue production.

The presidential order on drug shortages directs the FDA to take the following steps:

  • • Require drug manufacturers to provide notice of manufacturing disruptions for certain drugs.

  • • Expedite regulatory reviews to help address drug shortages.

  • • Communicate to the Department of Justice any findings of drug stockpiling or price gouging.

Proposal would require 2/3 vote for bylaws amendments

The AVMA House of Delegates will consider an amendment to the AVMA Bylaws to require a two-thirds vote of the HOD to approve all future bylaws amendments.

Currently, only a majority vote of the HOD is necessary to adopt any bylaws amendment that receives a recommendation of approval from the Executive Board. A two-thirds vote of the HOD is necessary to adopt any bylaws amendment that does not receive a recommendation of approval from the board.

The House Advisory Committee submitted the proposal to require a two-thirds vote to approve all future bylaws amendments. The HOD will consider the proposal at its regular winter session Jan. 6, 2012.

AVMA seeks nominations to Executive Board

The AVMA is sending a letter to each voting member in districts VII and IX to invite nominations for representatives who will serve on the Executive Board for the next six-year term, starting in August.

District VII comprises Iowa, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota. District IX comprises Arizona, Colorado, Kansas, New Mexico, Oklahoma, and Utah.

Feb. 1, 2012, is the deadline for receipt of nominations for district representatives. If a district has more than one nominee, the Association will mail a ballot to all voting AVMA members in the district.

Education council schedules site visits

The AVMA Council on Education has scheduled site visits to eight schools and colleges of veterinary medicine for 2012.

Site visits are planned for the University of Calgary Faculty of Veterinary Medicine, March 18–23; Michigan State University College of Veterinary Medicine, April 22–26; University of Sydney Faculty of Veterinary Science, June 3–7; Auburn University College of Veterinary Medicine, Sept. 16–20; Louisiana State University School of Veterinary Medicine, Sept. 30-Oct. 4; University of London Royal Veterinary College, Oct. 14–18; University of Montreal Faculty of Veterinary Medicine, Nov. 4–8; and Western University of Health Sciences College of Veterinary Medicine, Dec. 2–8.

The council welcomes written comments on these plans or the programs to be evaluated. Comments should be addressed to Dr. David E. Granstrom, Director, Education and Research Division, AVMA, 1931 N. Meacham Road, Suite 100, Schaumburg, IL 60173. Comments must be signed by the person submitting them to be considered.

Researchers say fungus causes deadly bat disease

A study published in the journal Nature purports to prove the Geomyces destructans fungus is causing a deadly illness responsible for catastrophic die offs among multiple bat species in eastern North America.

The investigation led by the U.S. Geological Survey is offered as the first direct evidence that G destructans is behind white-nose syndrome in bats.

Since the disease was first reported in January 2007 in New York state, the white-nose syndrome outbreak has spread to hibernating bats in more than a dozen states and four Canadian provinces. Biologists estimate more than a million bats have died of white-nose syndrome, making it the worst wildlife health crisis in memory, according to the U.S. Fish and Wildlife Service.

White-nose syndrome has been diagnosed in nine species of bats hibernating in eastern North America. Species known to be susceptible to the disease are the little brown bat (Myotis lucifugus), Indiana bat (M sodalis), northern long-eared bat (M septentrionalis), eastern small-footed bat (M leibii), tricolored bat (Perimyotis subflavus), and big brown bat (Eptesicus fuscus).

Insect-eating bats are estimated to save the U.S. agricultural industry nearly $4 billion annually in pest-control expenses. Earlier in 2011, the USFWS rolled out a national management plan addressing the threat posed by white-nose syndrome.

More than 100 state and federal agencies, tribes, organizations, and individuals are trying to contain the disease outbreak, the first epizootic ever documented in bats. Over the past several years, the Department of the Interior has invested close to $11 million in the effort, including more than $3 million for ongoing research looking for methods to control or cure the disease.

Debate over the role of G destructans in the WNS outbreak stems in part from an assumption that fungal infections in mammals are typically associated with immune system dysfunction. Moreover, G destructans was recently found to commonly colonize the skin of bats in Europe, where no unusually high bat mortality incidents have been reported. These factors have fueled speculation that the fungus is an opportunistic pathogen and that North American bats are dying as a result of unidentified factors.

Researchers at the USGS National Wildlife Health Center in Madison, Wis., exposed captive, healthy little brown bats to pure cultures of G destructans while the animals were hibernating. All the bats subsequently developed white-nose syndrome. Researchers also demonstrated the fungus can spread through contact between individual bats.

“While our study confirmed that G destructans is spread bat to bat, it is also important to note that virtually all pathogens, especially spore-producing fungi, are spread by multiple routes,” said USGS micro-biologist and study author David Blehert, PhD.

The study was conducted by scientists from the USGS, University of Wisconsin-Madison, Wisconsin Veterinary Diagnostic Laboratory, University of Tennessee-Knoxville, New York Department of Environmental Conservation, USFWS, Wisconsin Department of Natural Resources, and Bucknell University.

The Nature article, “Experimental infection of bats with Geomyces destructans causes white-nose syndrome,” was published online Oct. 26, 2011, at www.nature.com.

Russian, US vets collaborate on distemper threat to tigers

Russian and Wildlife Conservation Society veterinarians have teamed up to determine how serious a threat distemper is to endangered Siberian tigers.

Using a combination of histologic examination, PCR assays, and DNA sequencing at the WCS's Wildlife Health Center at the Bronx Zoo, the team characterized distemper infections in two wild Siberian tigers from the Russian Far East.

The diagnosis is a much-anticipated confirmation that wild tigers have been infected with the distemper virus, which the WCS and Russian veterinarians first documented in 2003.

The team, which includes veterinarians from the Primorskaya State Agricultural Academy and the Moscow Zoo, presented its findings this September at the first Russian symposium on wildlife diseases, in the city of Ussurisk.

In 2010, a gaunt female tiger with neurologic signs was shot dead when the animal wandered into a Russian village. A similar event occurred seven years earlier. In that instance, WCS staff immobilized the tiger, which later died in captivity.

Samples collected from the tigers were tested to make the distemper diagnosis. Whether the tigers contracted distemper from a wild animal or domestic dog, both of which are reservoirs for the virus, is not known.

Dr. Denise McAloose, the WCS's chief pathologist and lead investigator of the tiger study, noted the benefits of international collaboration in making the diagnosis. “Without our Russian associates there on the spot, knowing what samples to collect and how to preserve these specimens, samples would never have made it to our lab, and the cause of death would remain unknown.”

Recent years have seen a disturbing uptick in reports of unusual behavior in wild Siberian tigers, ranging from tigers entering villages to stalling traffic on major roadways—behavior possibly indicative of distemper.

Conservation organizations estimate as few as 3,200 Siberian, or Amur, tigers remain in the wild. The endangered animals are already in jeopardy as a result of poaching and habitat loss, but now they may face a new threat.

“With all the threats facing Siberian tigers from poaching and habitat loss, relatively little research has been done on diseases that may afflict tigers,” said Dale Miquelle, director of Russia Programs for the WCS. “There are no records of tigers entering villages and behaving so abnormally before 2000, so this appears to be a new development and new threat.”

“Understanding whether disease is a major source of mortality for Siberian tigers is crucial for future conservation efforts,” Miquelle added.

Dr. Irina Korotkova of the Primorskaya State Agricultural Academy says the East-West collaboration provides a foundation for elucidating potential disease threats to tigers in the Russian Far East. “Understanding the role of distemper in our wild Amur tiger population is vitally important,” Dr. Korotkova said.

Currently, the WCS is working with the Agriculture Academy in Primorskaya and others to establish a wildlife diagnostic laboratory in Ussurisk, although the facility is not expected to be adequately funded and fully functional for several years.

“Until then, there's still much to do, including identifying the source of the disease,” Dr. McAloose said.

Mystery illness killing Arctic ringed seals may be spreading

A mysterious disease that's killed scores of ringed seals off the Alaskan coast since last summer may also be affecting other species of Arctic marine wildlife.

The outbreak was first reported in July 2011 along the North Slope of Alaska. Severely ill and dead ringed seals were found with excessive hair loss and lesions on their faces and flippers. Other signs associated with the disease are delayed molt, lethargy, unusual behavior, and labored breathing.

By late October, government officials had received some 200 reports of sick or dead seals, mostly along the more than 200-mile expanse between the Alaskan cities of Point Lay to the south and Barrow to the north. Approximately 50 animals were dead or died a short time after being found.

Ringed seals are the most common and widely distributed of the Arctic seal species. Since July, ringed seals with the same telltale signs of the mystery illness have been documented in Russia and Canada.

Walruses with similar ulcerative skin lesions are turning up along the North Slope and western coast of Alaska while harp seals with marked hair loss have been sighted in Alaskan waters and around Greenland—indicators the outbreak may not be isolated to ringed seals.

On Oct. 13, the National Oceanic and Atmospheric Administration issued a statement saying it was not known whether the same disease is infecting multiple marine mammal species. Moreover, the agency acknowledged that the cause of the ringed seal illnesses and deaths had so far eluded discovery.

Samples have so far tested negative for poxvirus, parapoxvirus, herpesvirus, papillomavirus, morbillivirus, and calicivirus and are currently being tested for influenza virus.

Native communities living in the region hunt ringed seals and other marine mammals for food, and government officials are advising them against eating sick animals or feeding the meat to their dogs.

Dr. Kathy Burek, owner of Alaska Veterinary Pathology Services in Eagle River, began assisting in the disease investigation this August. By early November, Dr. Burek had performed necropsies on 10 ringed seal carcasses recovered from the North Slope.

The board-certified veterinary pathologist described the case animals as having excessive hair loss across their bodies as well as ulcerative and erosive lesions on their skin and inside their mouths. In all the seals, one or more pathologic abnormalities have been identified, including hepatitis; vasculitis and thrombosis in the skin, lungs, and spleen; lymphadenopathy; and lymphoid depletion.

Some features of the histopathologic and epidemiologic findings, such as unusual vacuolar changes, possible inclusions in the skin lesions, and a lymphoplasmacytic necrotizing hepatitis, could indicate a virus is behind the outbreak, Dr. Burek explained, hence the intense search for a primary viral etiology.

Dr. Burek has also seen signs suggestive of disseminated intravascular coagulation, including evidence of hemolysis and an unusual bleeding tendency in affected animals that were still alive. And, although vacuolar changes were evident in the cerebral and cerebellar white matter of two carcasses—a possible explanation for the abnormal behavior—Dr. Burek says further testing is necessary to determine whether the condition occurred while the animals were alive or after they had died.

Dr. Burek can't say with certainty what killed the seals, but she suspects the animals were terminally septicemic.

Alopecia and delayed molt have been observed in ringed seals around Alaska for the past couple years, according to Alaska State Veterinarian Bob Gerlach. He worries the recent cases of morbidity and mortality, along with the possibility other marine mammal wildlife in the Arctic are infected with the same agent, are signs of a more serious issue.

“This may not just be a problem for a specific species of marine mammals,” Dr. Gerlach said, “but could be a reflection of a larger problem across the entire Arctic coastal ecosystem.”

Dr. Gerlach and others involved in the investigation speculate that no single infectious agent or toxin is responsible for the outbreak. Rather, they wonder whether the animals are succumbing to a complex combination of stressors brought on by changes in their environment, such as warmer air and ocean temperatures and a diminished sea ice habitat.

But determining how the warmer Arctic climate could be a factor in the disease outbreak isn't easy. “The problem is how do you establish any correlation or causation between these particular disease issues and climate change?” noted Dr. Burek, who has written about the subject for the journal Ecological Applications.

Updated wildlife disease manual available

The latest edition of the American Association of Zoo Veterinarians' reference notebook on infectious diseases of captive and free-ranging wildlife in North America can be downloaded for free at www.aazv.org.

The peer-reviewed “Infectious Disease Manual 2011” is intended as a resource for clinicians, pathologists, and wildlife biologists facing a potential infectious disease situation. Along with fact sheets on more than 150 transmissible animal diseases, the AAZV manual lists reportable diseases and regulations for all 50 states, Canada, and Mexico.

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