ARS | Publication request: Performance of Yellowstone and Snake River Cutthroat Trout Fry Fed Seven Different Diets.

Submitted to: North American Journal of Aquaculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 24, 2009
Publication Date: July 13, 2009
Repository URL: http://riley.nal.usda.gov/nal_web/digi/submission.html
Citation: Kindschi, G.A., Myrick, C.A., Barrows, F., Toner, M., Fraser, W.C. Performance of Yellowstone and Snake River Cutthroat Trout Fry Fed Seven Different Diets. North American Journal of Aquaculture 71:325-329.

Interpretive Summary: Cutthroat trout are not raised commercially, unlike rainbow trout, since they do not grow quickly or adapt well to hatchery conditions. However, many States are not requiring commercial fish farmers to produce the native cutthroat trout rather than the non-indigenous rainbow trout for stocking private ponds. In order for this to be commercially feasible appropriate diets and rearing techniques needed to be identified. Five commercial diets and two formulated feeds were fed to initial-feeding Yellowstone cutthroat trout fry and Snake River cutthroat trout fry for 18 weeks to evaluate fish performance. Commercial feeds considered to be premium due to their composition and cost produced the highest survival and growth rates. Feeds that typically support good growth and survival of rainbow trout were not as effective with cutthroat trout.

Technical Abstract: Five commercial diets and two formulated feeds were fed to initial-feeding Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri fry and Snake River cutthroat trout O. clarkii spp. (currently being petitioned for classification as O. clarkii behnkei) fry for 18 weeks to evaluate fish performance. Eyed eggs from Yellowstone and Snake River cutthroat trout were received from the Yellowstone River State Fish Hatchery and Jackson National Fish Hatchery, respectively. Each diet was fed to four tanks of each subspecies of cutthroat trout (7 diets × 4 tanks/diet × 2 cutthroat trout subspecies = 56 tanks). Skretting Nutra-Plus provided optimal fish weight, total length, survival, and feed conversion for Yellowstone cutthroat trout. The weight and total length of Snake River cutthroat trout were also greatest when fish were fed Skretting Nutra-Plus. Skretting Nutra-Plus is no longer available, but Skretting/Bio-Oregon Bio-Vita is very similar; this feed and similar premium feeds from other manufacturers should be considered for future cutthroat trout propagation programs.