Effects of Dietary Cottonseed and/or Canola Oil Inclusion on the Growth Performance, FA Composition and Organ Histology of the Juvenile Rainbow Trout, Oncorhynchus mykiss

Engin, Kenan

This study aimed at demonstrating the effects of total and 50% dietary fish oil replacement by cotton seed and canola oils and a mixture of these vegetable oils (VOs) on growth, tissue fatty acid composition and histology of digestive organs in the juvenile rainbow trout for 84 days. Five iso-nitrogenous and lipidic diets were formulated to replace dietary fish oil (FO) totally by cotton seed oil (CSO), canola oil (CO) and an equal or 50% FO/ 50% VO mixture. Duplicate groups of 50 fish (~15 g) were fed two times daily to apparent satiation. Growth performance, feed efficiency and viscerosomatic index were not influenced by dietary treatments (P>0.05). However, hepatosomatic index was significantly higher (P