Effect of diets containing sesame oil on growth and fatty acid composition of rainbow trout (Oncorhynchus mykiss)

Abstract

Summary The aim of this study was to investigate effects of fish oil replacement by sesame oil in combination with other vegetable oils in diets with regard to growth performance, feed utilization, desaturation and elongation, whole fish and liver fatty acid profiles of juvenile rainbow trout. Sesame oil (SO) used in the feeds was a mixture of linseed (LO), sunflower (SFO) and fish oil (FO), whereas the control diet contained only FO. Duplicate groups of 60 rainbow trout (~7 g) held under similar culture conditions were fed 2% of their body weight per day for 75 days. At the end of feeding trials, there was no difference in feed utilization efficiency or growth performance between the control group and the groups with added sesame oil (P > 0.05). However, viscerosomatic and hepatosomatic index values were significantly higher (P 0.05). Diets with sesame oil increased desaturation and elongation of 18 : 3n-3 towards n-3 HUFA. The conclusion was that the diet addition of sesame oil in combination with other vegetable oils increased the nutritional quality of the whole fish and liver of juvenile rainbow trout, in particular the docosahexaenoic acid (DHA) level. Therefore, sesame oil may be of interest for use in aquaculture.