July 3, 2007

Progress Being Made on Disease That Kills Fish: Colorado Division of Wildlife Monitors Poudre River
CBS4 - cbs4denver.com
02 Jul 2007
Area: Colorado USA

Ken Kehmeier vividly remembers that day 17 years ago when everything changed - the day whirling disease first was discovered in the Poudre River. Kehmeier, the Colorado Division of Wildlife's fishery biologist for the Poudre, North Platte and Laramie river systems, was doing a routine check at one of six testing sites along the Poudre. The tests previously had been done on an annual basis, but after the tests produced the same negative results year after year, the decision was made in 1988 to test the water every two years. Two years later, when Kehmeier returned to sample the Poudre, tests proved that whirling disease - a potentially devastating malady that can wipe out populations of trout and salmon - had arrived.

"To this day, that bugs me more than anything else in my career," the 22-year DOW veteran said. "I feel like I missed something, and it came back to haunt us." Whirling disease attacks young fish when their skeletons still are cartilage. While the fish don't always die, the parasitic disease often deforms fish and can cause them to display the tail-chasing behavior that gives the disease its name.

Dying Sea Birds Showing Up on Hilton Head Island Shore
The Island Packet - islandpacket.com
03 Jul 2007
P Frost
Area: United States

State and federal wildlife officials are investigating the deaths of hundreds of sea birds turning up on the coasts of South Carolina, Georgia and Florida. Wildlife biologists say more than 1,000 shear-waters -- large, gull-like water birds that spend most of their lives far offshore until they nest -- have been found dead over the past two weeks on Southeastern beaches. Since last week, more than 160 of the dead birds have been found in South Carolina, including at least 22 on Hilton Head Island. Officials remain uncertain about what's causing the mass casualties, but they say most of the birds recovered appear to have died of dehydration and malnutrition during migration.

Most shearwater carcasses recovered in South Carolina appear to be those of juvenile birds, said Craig Watson, a wildlife biologist with the U.S. Fish and Wildlife Service in Charleston. A small percentage have been found alive. "For some reason, these birds are dying, and most think it's due to starvation," he said. "Whatever the reason, this appears to be pretty significant; we just don't know how significant yet."

Related Article

Lake Monroe Duck Deaths Puzzle Wildlife Authorities
Orlando Sentinel - orlandosentinel.com
03 Jul 2007
R Perez
Area: Florida USA

The number of mysterious mallard deaths at Lake Monroe has reached nearly 70, and state wildlife investigators have no idea why the ducks are dying. The number of dead ducks found daily since last week around Marina Island has ranged from a single duck to a peak of 34 Friday. "We had seven more this weekend," said Joy Hill, a spokeswoman for the Florida Fish and Wildlife Conservation Commission, which is leading the investigation. The state Department of Environmental Protection sent a staff biologist to the area Monday to look for any potential environmental causes for the deaths, said Jeff Prather, a DEP spokesman.

Tests on water samples taken from the lake found a form of blue-green algae, Prather said. "We're taking a look at that," he said. "But there is nothing definitive so far." The results of necropsies -- animal autopsies -- and tests on blood taken from two dying birds have not produced answers, but the deadly effects appear to be expanding. Early on, only juvenile ducks were dying, but the deaths now run from ducklings to adults.

Organism ID‘d that May Be Killing Sheep
Associated Press (Posted by localnewswatch.com)
02 Jul 2007
K Reidler
Area: United States

An organism that may have played a part in killing thousands of bighorn sheep in the West over the last five decades and in thwarting repopulation efforts has been isolated in a lab and found in struggling bighorn herds in the wild, biologists say. Biologists say that could be the initial organism that attacks the sheep and works by inhibiting the ability of hairlike structures in airways to eliminate bacteria that lead to deadly pneumonia. "This is the first problem I‘ve worked on where there is quite a bit of evidence piling up where the agent is a mycoplasma," said Tom Besser, a professor in WSU‘s department of veterinary microbiology and pathology. He works at the Washington Animal Disease Diagnostic Laboratory on the school‘s Pullman, Wash., campus.

Among adult bighorns that hadn‘t previously been exposed to mycoplasma, 25 percent to 75 percent die, she said, noting the variation could be due to how many were initially exposed or to how virulent a strain of the disease is at work. After WSU researchers identified the mycoplasma, biologists in Idaho, Washington, Oregon, California and the Canadian province of Alberta sent the researchers blood samples previously collected from 18 herds. "We found some really promising patterns and things seemed to fit together really well," Cassirer said. Biologists say about 2 million bighorns once inhabited the West, but they disappeared over most of their range in the 1800s and early 1900s due to unregulated hunting and disease believed to have been carried by domestic animals.

Manganese Levels Increase in Scrapie-Infected Sheep before Clinical Symptoms Develop
University of Bath (Posted by sciencedaily.com)
02 Jul 2007
Area: United Kingdom

Sheep infected with scrapie and cows infected with BSE have elevated levels of manganese in their blood before clinical symptoms appear, according to new research. The findings, published in the Journal of Animal Science, also show that scrapie-resistant sheep produce elevated levels of the metal when “challenged” with the disease. This suggests that elevated manganese levels in the blood and central nervous system are caused by the animal’s initial response to the disease. The findings raise the possibility of using manganese levels in the blood as a potential diagnostic marker for prion infection.

At present, only post-mortem examination of the brain tissue gives a certain diagnosis. Scrapie, Bovine Spongiform Encephalopathy (BSE) and Creutzfeldt-Jakob Disease (CJD) are neurodegenerative diseases that affect the brain and nervous system of sheep, cows and humans respectively. They are transmitted by mis-formed prion proteins which cause tiny loss of brain cell in different regions of the brain, leading to impairment of brain function, including memory changes, personality changes and problems with movement that worsen over time. “Definite diagnosis of prion disease is currently only possible post-mortem," said Professor David Brown from the University of Bath who led the study with colleagues from the universities of Hull and Edinburgh.

Fish Kill: Fertilizer Nitrates May Be to Blame for 500 Dead Parleys Creek Trout
The Salt Lake Tribune - sltrib.com
03 Jul 2007
B Prettyman
Area: Utah USA

Salt Lake City and state officials believe exceptionally high levels of nitrate are responsible for a widespread fish kill on Parleys Creek last week, but they still don't know how it got into the water. "You can get nitrates from fertilizers. That's the first thing that pops into my mind," said Florence Reynolds, who is in charge of water quality and treatment for Salt Lake City. "I don't know what other kinds of material would have a heavy enough nitrate level to show up like that."

The nitrate level in the creek at Parleys Nature Park near the mouth of Parleys Canyon was 1.66 milligrams per liter June 26 at 8 a.m. when a Salt Lake City water-quality and treatment monitoring station collected a sample as part of a water-quality project. Last week's numbers were even more alarming at a station near Sugar House Park, where the nitrate level was 21.05 milligrams per liter. Nitrates that reach 4 milligrams per liter are toxic to cold-water fish, like the more than 500 Bonneville cutthroat trout found dead in the creek. The highest nitrate level previously recorded on Parleys Creek was 0.8.

Other Wildlife Disease Related News

Global Disease Detection Program Key Part of Worldwide Network

When Good Neighbours Become Good Collaborators

Mystery of the Missing Lure

Journal Article(s) of Interest

Susceptibility of Cattle to First-Passage Intracerebral Inoculation with Chronic Wasting Disease Agent from White-tailed Deer [online abstract only]
Vet Pathol. 2007; 44: 487-493
AN Hamir et al.

The Toxic Origins of Disease [free full-text available]
PLoS Biol. June 2007; 5(7): e193
L Gross

Prion Protein Alleles Showing a Protective Effect on the Susceptibility of Sheep to Scrapie and Bovine Spongiform Encephalopathy [online abstract only]
J. Virol. July 2007; 81(13): 7306-7309
G Vaccari et al.

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