Nutrient Requirements of Haddock,Melanogrammus aeglefinus

摘要

The main fish and shellfish species farmed in Canada include Atlantic salmon,rainbow trout,mussel,oyster,scallop and clam.In the past six years,our institute has directed nutrition research towards haddock,halibut and cod.This paper reviews our recent findings on lipid,protein,energy and phosphorus utilization by haddock.Unlike salmonids,growth and feed efficiency are not significantly affected by increasing the lipid content of the diet(12-22 %),however,the higher amounts of dietary lipid(>12 %) cause a significant increase in hepatosomatic index(HSI;9.8-12.1%) and total liver lipid(63.2-69.0%) in juvenile fish. The development of feeds for this potential new marine fish species for aquaculture must be based on sound information regarding the nutrient requirements,digestion,absorption and retention of major nutrients and energy utilization from various feed ingredients.Until recently,the field of haddock nutrition remained unexplored.Our preliminary research has shown that diet containing high amounts of protein(50-55 %),low carbohydrate(<14%),low lipid(<15 %) with a sufficient amount of n-3 long chain polyu nsaturated fatty acids(1.5-2.0 % eicosapentaenoic and docosahexaenoic f atty acids) and well fortified with vitamins and trace elements is suitable for initial feed formulations of haddock growout diets.Higher amounts of dietary lipid(>12 %) cause fatty liver and an increase in hepatosomatic index.The best growth,feed utilization and nutrient digestibility and minimal increase in HSI of juvenile fish have been obtained with a diet containing 54.6% crude protein(51.3% DP),11.4% lipid,17.0 MJ/kg DE and a DP/DE ratio of 30.2 g DP MJ DE-1.The paper has briefly reviewed the role of certain critical nutrients(protein and amino acids,essential fatty acids,minerals,vitamins),energy utilization,feeds and feeding for haddock.