American trout may get boost from expatriate trout

DENVER -- Scientists may be able to partly contain whirling disease, introduced to the United States by fish imported from Europe, with the help of a disease-resistant American trout that has dwelled on the continent for a century.

"We have been looking very hard in North America for whirling-disease resistant trout and haven't found any. We have found a fish that was moved to Germany from the United States in 1880 or 1890 that is very promising," said epidemiology professor Ronald Hedrick of the University of California-Davis, perhaps the leading U.S. authority on the disease.

Hedrick and his research associate, fish biologist Mansour El-Matbouli of the University of Munich, said the trout in question was imported into Germany 120 or so years ago. Their report on El-Matbouli's findings was recently presented to the Eighth Whirling Disease Symposium.

After the resistance was discovered, El-Matbouli exposed the trout to whirling disease. The trout seemed to be able to survive the disease as well as brown trout, long known to be generally resistant.

It wouldn't be the first time an expatriate had come to the aid of an industry: The same thing happened with the French vineyards in the 1870s when French vines were grated onto American roots resistant to Phylloxera, which was ravaging the industry.

"Biologists had told us that if we wait a century our problem may be solved. Turns out we have fish that have already been challenged by the disease for a century," said Pete Walker, state fish pathologist.