Juvenile, red hybrid tilapia were fed diets containing cod liver oil (0%, 4%, 8%, 12% of total diet) substituted
against corn oil. After 10 weeks, no significant differences between treatments were seen in weight gain,
specific growth rate, feed conversion ratio, whole body or dorsal muscle (fillet) proximate composition.
Gas chromatography revealed significant differences in the total n-3 content and fatty acid profiles of
dorsal muscle. The total n-3 content of dorsal muscle increased from 7.6% to 18.6%, total n-6 content fell
from 37.5% to 12.9% and docosahexanaenoic acid increased from 5.8–16.1% of total fatty acids, in fish fed
0% and 12% fish oil, respectively. The retention of eicosapentaenoic acid was low in all dietary groups,
possibly indicating selective use as a substrate for b-oxidation. The results demonstrate the potential
to enhance the total n-3 fatty acids and docosahexaenoic acid in tilapia fillets by increasing dietary fish
oil.