At ARS\'s National Center for Cool and Cold Water Aquaculture (NCCCWA) in Leetown, West Virginia, molecular biologist Greg Wiens, geneticist Timothy Leeds and their colleagues have developed a new line of rainbow trout that is resistant to bacterial cold-water disease (BCWD), as well as a susceptible line and a control line to use in studies.
BCWD, which is caused by the bacterium Flavobacterium psychrophilum, affects trout, salmon and other cold-water fish species and causes substantial economic loss to the aquaculture industry each year.
Scientists are studying how genetic breeding changes disease resistance properties in trout. With the help of industry and government collaborators, Wiens evaluated the performance of the control, susceptible and disease-resistant trout lines under farm conditions before and after natural exposure to the bacterium. The disease-resistant line had a higher rate of survival than the control or susceptible lines after exposure.
\"In addition, fewer disease-resistant fish harbored the pathogen in their internal tissues compared to the control and susceptible fish during the outbreak,\" Wiens says.
