Evaluation of a canola protein concentrate as a replacement for fishmeal and poultry by-product meal in a commercial production diet for Atlantic salmon (Salmo salar)

Abstract

Atlantic salmon (<em>Salmo salar</em>) is an important cultured carnivorous species that, in the past, has not tolerated high levels of most plant protein feed ingredients in their diet. In order to increase efficiency and production to meet global demand, new sources of protein must be incorporated into the aquafeeds. A 38-week feeding trial was conducted at the National Cold Water Marine Aquaculture Center (Franklin, ME, USA) with juvenile Atlantic salmon (133 g per fish, initial weight) to determine the effect of feeding graded levels of canola protein concentrate (CPC) in a commercial-type diet. A commercial diet (Signature Salmon 3.5 mm, Northeast Nutrition, Truro, Nova Scotia, Canada) was modified and analyzed by the manufacturer to contain 10% or 20% canola protein concentrate, replacing fishmeal and poultry by-product meal. Fish fed diet containing 20% canola protein concentrate had significantly lower growth compared with those fed 0% canola protein concentrate diet (<em>p</em> = 0.04). There was not any significant difference in feed efficiency (<em>p</em> = 0.22) or protein efficiency ratio (<em>p</em> = 0.21). There was not a significant difference in growth comparing the salmon fed the 0% CPC and the 10% CPC diets (<em>p</em> > 0.05). Canola protein concentrate significantly depressed growth when included in the diet at 20%, but not at 10%, indicating that canola may be used as a minor feed ingredient when available.