Hatchery Performance of a Whirling-Disease Resistant Strain of Rainbow Trout

The hatchery and field performance of a whirling disease resistant strain of rainbow trout (Oncorhynchus mykiss) was compared to a traditional Utah strain: Ten Sleep (TS). The resistant strain consisted of progeny from a German strain (GR) x Harrison Lake strain (HA) backcrossed with the German strain, resulting in fish that were 3⁄4 German strain x 1⁄4 Harrison Lake strain. The disease resistance of the GR and HA strains have been documented in laboratory studies by Hedrick et al. (2003) and Wagner et al. (2006). The GR strain was originally from the Gunnison River in Colorado, shipped to Germany in the 1880s and subsequently used for aquaculture. Now, over a century later, after exposure to Myxobolus cerebralis for generations, the strain is being evaluated for use in stocking programs in Colorado, Utah and other states.