Lipid nutrition of haddock (Melanogrammus aeglefinus ): Alternate lipid sources and the role of vitamin E as a biological antioxidant

The main objective of this thesis research was to evaluate the potential for partially replacing marine fish oil in diets for juvenile haddock with flaxseed, canola and sunflower oils and poultry fat. Two long term feeding studies and one digestibility trial were conducted to achieve this. Haddock were fed diets where alternative lipid sources replaced 65% of anchovy oil for 18 weeks. Growth, survival, feeding efficiency and tissue lipid content (ca. 1% muscle and ca. 80% liver) were unaffected. Feeding alternative lipid sources significantly decreased (P<0.05) tissue EPA and DHA, as well as leukocyte arachidonic acid. Lipid digestibility was generally excellent (≥90% ADC) and did not vary between treatments after feeding alternative lipid sources to haddock for 3 weeks. PUFA were well digested (ca. 95% ADC), while saturates were generally less well digested (55-90% ADC). (Abstract shortened by UMI.)...