Use of dietary oil, solvent-extracted meal and protein concentrate from Camelina sativa for rainbow trout, Oncorhynchus mykiss, at the early fry stage

A 98-day feeding trial was conducted in a 24-tank freshwater flow-through system (13 +/- 0.5 degrees C) to evaluate the effects of using dietary camelina oil (CO), solvent-extracted camelina meal (SECM), and camelina protein concentrate (CPC) in early fry diets for rainbow trout (initial weight 1g/fish, 50 fish/tank). Triplicate tanks were randomly fed one of eight diets including aCamelina sativafree control diet, two diets containing CO at either 50 or 100% replacement of fish oil, three diets containing 6, 12, or 18% SECM, and two diets containing 6 or 12% CPC. Dietary replacement of 100% of added fish oil with CO, and dietary inclusion of up to 18% SECM or 12% CPC did not result in significant reductions in growth and feed efficiency, or changes in proximate whole-body carcass composition and hindgut morphology of rainbow trout fry. However, fish fed diets containing 18% SECM, did require a longer acclimation period to the feed and, ultimately, gained less weight, presumably due to a poorer protein utilization efficiency in the early days of the trial.