Transcript Whirling Disease

By Linda Tucker
Background Information
 Myxobolus cerebralis
 Native to Europe and first described in 1903
 Currently found in Europe, United States, northern Asia,
New Zealand, Morocco, Lebanon, and South Africa
 First confirmed in the United States in 1958 in
Pennsylvania
 Has spread to 25 states
Life Cycle of M. cerebralis
Life Cycle of M. cerebralis
Life Cycle of M. cerebralis
Life Cycle of M. cerebralis
Effects on Fish
 Only affects salmonid species
 Younger fish are more susceptible than older fish
 Rainbow Trout is the most susceptible species
 Symptoms include skeletal deformities, black tails,
and whirling behavior
 Can slow growth and increase mortality
Spinal Deformity and Black Tail
Head Deformity
Whirling Behavior
Impacts on Wild Populations
 Wild populations declined in Western U.S.
 Eastern and western coastal populations stable
 Decline of single trout species can lead to community
composition changes
 Food web affected
Impacts on Fish Hatcheries
 Destruction of infected fish
 Disinfection and renovation of facilities
 Closure of some facilities
 Money lost and money spent
Prevention in the Wild
 Wash and dry all equipment when moving between
bodies of water
 Don’t transfer live fish from one place to another
 Dispose of unused bait in the trash
 Never discard fish parts near the water
Prevention in Fish Hatcheries
 Only use groundwater sources for water
 Purchase fish that are certified to be whirling disease
free
 Line raceways with concrete
 Frequently clean solids from settling areas
Treatment
 There is no treatment for infected fish
 Remove infected fish
 Disinfect
 Follow prevention methods to avoid reintroduction
Questions?