Open AccessEffects of partial or total replacement of fish meal with freeze‐dried krill ( Euphausia superba ) on growth and nutrient utilization of juvenile Atlantic cod ( Gadus morhua ) and Atlantic halibut ( Hippoglossus hippoglossus ) fed the same practical diets
Author(s) -
TIBBETTS S.M.,
OLSEN R.E.,
LALL S.P.
Publication year - 2011
Publication title -
aquaculture nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.941
H-Index - 79
eISSN - 1365-2095
pISSN - 1353-5773
DOI - 10.1111/j.1365-2095.2010.00753.x
Subject(s) - halibut , hippoglossus hippoglossus , gadus , biology , krill , atlantic cod , fishery , euphausia , meal , fish meal , nutrient , zoology , food science , fish <actinopterygii> , ecology
Studies were conducted with juvenile (28 g) Atlantic cod ( Gadus morhua ) and halibut ( Hippoglossus hippoglossus ) fed fish meal (FM) based diets with partial (0%, 25%, 50% and 75%) or total (100%) replacement of FM with freeze‐dried krill (FDK). Addition of dietary FDK significantly stimulated feeding activity in both species and resulted in higher feed consumption and intakes of digestible protein (DP) and energy (DE). This is a significant finding on the feed attractant properties of FDK because it occurred despite having 2–4 MJ kg −1 higher levels of DE in the FDK diets which could have had an intake suppression effect. In addition, it indicates that the soluble protein fraction of krill thought to be responsible for its attractant properties and is routinely lost or greatly reduced during commercial processing of krill meals, is retained by freeze‐drying. Supplementation of FDK significantly improved growth rates, digestibility and nutrient utilization. Levels exceeding 25–50% FM replacement, however, generally did not significantly increase growth performance or nutrient utilization. In addition, feed formulations with high FDK (>75% replacement) are likely to be cost‐prohibitive as long as the market price remains higher than FM.