IUBio Biosequences .. Software .. Molbio soft .. Network News .. FTP

Salmonid whirling disease

John E. Grant jgrant1 at emerald.tufts.edu
Mon Feb 6 21:46:11 EST 1995

Recently reports from Montana indicate that a possible reason for the 
dramatic decrease in native rainbow trout populations on the Madison 
river is the introduction of what is known as Whirling disease.  The 
disease is caused by a protozoan parasite that attacks the brain and 
spine of trout and salmon.  The fish lose their equilibrium, causing 
them to swim in circles until they starve to death or are attacked by 

The Protozoan is Myxobolus cerebralis.  It has a multi-stage life cycle 
in two hosts, early stages in the tubifex or sludge worm and later stages 
in the trout.  It is endemic to Europe, therefore brown trout (also from 
Europe) are less susceptible than American rainbows, which are thought to 
have 85-95% mortality in infected waters.  If there is any information on 
how to control this or related protozoans, it would be greatly 
appreciated.  I am a Biology student at Tufts University and an avid 
fly-fisherman so I have double interest in the topic.  Thanks for any help.

John E. Grant		  |"This morning I shot two holes in my freezer,
jgrant1 at emerald.tufts.edu | I think I've got cabin fever,
Parrothead logician	  | I've gotta go where it's warm." -J. Buffett

More information about the Parasite mailing list

Send comments to us at biosci-help [At] net.bio.net