Cat parasite killing otters; Michigan's perch pressured; HACCP for medicine

December 17, 2002

Parasite In Cats Killing Sea Otters
Offering a partial explanation to a mysterious decline in Southern Sea Otter population, California Sea Grant researchers have established a strong body of circumstantial evidence linking cats to a lethal otter disease. University of California at Davis professor Patricia Conrad and doctoral student Melissa Miller, both in the School of Veterinary Medicine, have shown that otters near heavy freshwater flows are three times more likely to have been infected by Toxoplasma gondii - a potentially lethal parasitic protozoan that causes brain infections in otters - than otters from areas where runoff is light.

The scientists' best guess is that parasite eggs in cat droppings are washed into coastal-bound storm drains and creeks. Although many different kinds of animals, such as birds and rodents, can serve as intermediate hosts for the parasite, cats are the only animals known to shed the parasite's eggs in their droppings. Otters may be acquiring parasites directly through water contact, or they may be eating infected mussels or other bivalves.

Southern Sea Otters are listed as threatened under the federal Endangered Species Act. Once numbering more than 300,000, there were an estimated 2,100 otters off California this past spring. For more than a decade, otter numbers rose, hitting a peak in the spring of 1995. The recovery, for reasons still unexplained, appears to have stagnated or slid backward.

While the scientists are not certain how much of this decline can be attributed to the parasite infections, Miller's Sea Grant research suggests that about 60 percent of dead otters in her survey had been infected by the parasite. Further research suggests that many of these otters likely died of toxoplasma encephalitis.

To further investigate pathogens in storm water and runoff, a California Sea Grant study is looking at another parasite, Cryptosporidium, widely regarded as one of the most significant causes of diarrhea in humans. Conrad, and Rob Atwill, also at the School of Veterinary Medicine at Davis, are taking cues from the sea otters study, measuring pathogen levels in bivalves near outfalls of human and agricultural runoff, to track the upstream sources of pollution. Genetic tests are also being used to identify which animal species are the main sources of pathogen pollution. Wildlife, cattle, pets and people can spread Cryptosporidium.

Contact: Patricia Conrad, California Sea Grant Researcher, Professor of Veterinary Medicine, University of California at Davis; Office Phone: 530-752-7210; Email: paconrad@ucdavis.edu
Rob Atwill, California Sea Grant Researcher, Professor of Veterinary Medicine, University of California at Davis; Office Phone: 559-688-1731; Email: vmtrc.ratwill@ucdavis.edu

Eurasian Ruffe May Increase Pressure on Lake Michigan Yellow Perch
Eurasian ruffe, an invasive fish whose numbers have multiplied dramatically in Lake Superior, have now been spotted in northern parts of Lake Michigan. The good news is that round gobies, which are already abundant in Lake Michigan, may keep ruffe numbers down. The bad news is that Eurasian ruffe will nonetheless deplete resources for yellow perch, an important native sport fish.

With funding from Illinois-Indiana Sea Grant, Gary Lamberti, University of Notre Dame, and Martin Berg of Loyola (Ill.) University have been studying the relationship among Eurasian ruffe, round gobies and zebra mussels, and how this "exotic triad" can affect yellow perch. "Exotic species now dominate the food webs of the Great Lakes, including Lake Michigan," says Lamberti.

The researchers found that although the relationship between these invaders is complex, one fact is simple. The successful species is often the one that gets there first, noting that in Lake Superior Eurasian ruffe have become the dominant fish, while in Lake Michigan, round gobies have become numerically dominant, relegating ruffe to deeper waters.

Yellow perch in Lake Michigan are pressured early in life by competition from zebra mussels and round gobies. Zebra mussels filter plankton that larval perch need to grow. Gobies not only eat yellow perch eggs, they also compete with young perch for invertebrate food. Even a diminished ruffe presence will further impact the young perch.

As yellow perch grow larger they move to deeper waters, as do ruffe. Unlike larger yellow perch, ruffe prefer the bottom habitat, but nonetheless the two species will continue to tap the same food sources.

"The addition of Eurasian ruffe to Lake Michigan waters will likely increase the bottleneck on yellow perch," said Lamberti. "The native fish will experience increased competition during several stages of its life."

Contact: Gary Lamberti, Illinois-Indiana Sea Grant Researcher, Associate Professor of Biology, University of Notre Dame; Phone: (574) 631-8075; E-mail: Lamberti.1@nd.edu
Martin Berg, Illinois-Indiana Sea Grant Researcher, Assistant Professor of Biology, Loyola (Ill.) University; Phone: (773) 508-8853; E-mail: mberg@luc.edu

Sea Grant's HACCP Alliance Finds Role In Medical Profession
Long considered a model in how an industry can adapt rapidly to implementing federal safety guidelines, the National Sea Grant Program's Seafood HACCP ((Hazard Analysis and Critical Control Points) Alliance has spread its gospel of quality assurance to the medical industry.

Five years ago the United States medical device industry sought to implement a risk analysis and risk management tool that would further increase the safety of their products. Their goal was to find both a regulatory paradigm that would increase accountability, and also a process to reduce waste, curtail the production of defective or substandard devices or products, and implement an efficient and effective quality assurance program at each manufacturing facility.

It didn't take long for them to learn of Sea Grant's accomplishments. Turning to the guidance of Virginia Sea Grant researcher George Flick, a national leader of Sea Grant's seafood HACCP efforts, the medical device industry used that Sea Grant Seafood Alliance model to develop a complete curriculum for HACCP implementation in the medical device industry. The program, which originally focused on medical devices, now includes chemotherapeutics, blood, and tissues. The success of the program was further recognized in October, 2002 when it was adopted by the Canadian Blood Service as their standard for certifying the safety and purity of the Canadian blood supply.

Flick is one of the leaders of the National Sea Grant Seafood HACCP Alliance and currently serving as Chairman of the Medical HACCP Alliance that has established itself as a public interest organization and includes representatives from major healthcare product manufacturing firms.

Contact: George Flick, Virginia Sea Grant's Marine Advisory Service, Virginia Tech University, Office Phone: (540) 231-6965; E-mail: flickg@vt.edu

SEA GRANT WEB SPOTLIGHT:
Madison Jason
http://www.seagrant.wisc.edu/kidsteachers/madisonjason/
An international, interdisciplinary program that uses state-of-the-art technology such as the Internet and satellite feeds to enable 4th- through 8th-grade students to see and talk with scientists and researchers doing fieldwork in remote locations in the world. Site also provides professional development for teachers.

Features include profiles of Great Lakes fish, birds, and frogs; interactive quizzes; guides to student and teacher resources, interviews with scientists, and student art and projects as developed as part of the JASON Project curriculum. This award-winning site is run by Wisconsin Sea Grant.

SEA GRANT CALENDAR SPOTLIGHT:
Enhancing the Quality and Markets for Alaska Salmon
January 27, 2003 - January 28, 2003, Anchorage, Alaska
"Enhancing Quality and Markets for Alaska's Salmon," scheduled for January 27-28 in Anchorage, is the second in a series of statewide workshops addressing the economic crisis facing Alaska's salmon industry and its coastal communities. The workshops are part of a University of Alaska, Alaska Sea Grant and Washington Sea Grant initiative called "Tools for the Salmon Industry." For more information contact Paula Cullenberg, University of Alaska Marine Advisory Program, (907) 274-9691, E-mail: paulacullenberg@uaa.alaska.edu, Event Web Site: http://www.sfos.uaf.edu/salmontools/index.html
-end-
Sea Grant is a nationwide network of 30 university-based programs that works with coastal communities and is supported by NOAA. Sea Grant research and outreach programs promote better understanding, conservation, and use of America's coastal resources. For more information about Sea Grant visit the Sea Grant Media Center Website at: www.seagrantnews.org, which includes on-line keyword searchable database of academic experts in over 30 topical areas.

National Sea Grant College Program

Related Parasite Articles from Brightsurf:

Finding the Achilles' heel of a killer parasite
Two studies led by UT Southwestern researchers shed light on the biology and potential vulnerabilities of schistosomes -- parasitic flatworms that cause the little-known tropical disease schistosomiasis.

Your brain parasite isn't making you sick -- here's why
The new discovery could have important implications for brain infections, neurodegenerative diseases and autoimmune disorders.

Malaria parasite ticks to its own internal clock
Researchers have long known that all of the millions of malaria parasites within an infected person's body move through their cell cycle at the same time.

Malaria runs like clockwork; so does the parasite that causes the disease
A new study uncovers evidence that an intrinsic oscillator drives the blood stage cycle of the malaria parasite, P. falciparum, suggesting parasites have evolved mechanisms to precisely maintain periodicity.

Discovery of malaria parasite's clock could pave way to new treatments
The parasite that causes malaria has its own internal clock, explaining the disease's rhythmic fevers and opening new pathways for therapeutics.

New research shows how the malaria parasite grows and multiplies
Scientists have made a major breakthrough in understanding how the parasite that causes malaria is able to multiply at such an alarming rate, which could be a vital clue in discovering how it has evolved, and how it can be stopped.

Malaria parasite lives on the edge
The parasite that causes malaria expresses genes that code for the proteins it will need in later life stages, but uses two separate schemes to prevent these proteins from actually being made until they are needed.

Parasite paralysis: A new way to fight schistosomiasis?
Scientists have isolated a natural chemical that acts as a potent kryptonite against parasitic worms that burrow through human skin and cause devastating health problems.

Novel compound interrupts malaria parasite's lifecycle
Compound inhibits key enzymes, interrupting the parasite's lifecycle in human organisms and preventing transmission to vector insects.

Sweet success of parasite survival could also be its downfall
University of York scientists are part of an international team which has discovered how a parasite responsible for spreading a serious tropical disease protects itself from starvation once inside its human host.

Read More: Parasite News and Parasite Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.