Effect of different levels of Fish oil and Canola oil on diet on growth, survival and body Chemical Composition of Fattening Rainbow Trout (Oncorhynchus mykiss)

The effect of marine oils has been proven in many diseases due to the presence of n-3 fatty acids. Most of the clinical effects of n-3 fatty acids are due to the presence of Docosahexaenoic acid (DHA( and Eicosapentaenoic acid (EPA), which has so far not been found in any other food, except in fish. The purpose of this study was to investigate the effects of different levels of fish oil and canola oil on diet, on growth, survival and body chemical composition of Fattening rainbow trout (Oncorhynchus mykiss) Which ultimately can compensate for the deficiency of n-3 fatty acids in the household food basket and it is an important step towards the health of the community. For this purpose, three experimental diets were prepared with the same protein level (40%) and different fat levels (the first diet with 10% fish oil, the second diet with 10% canola oil and the third diet with 5% fish oil and 5% canola oil) and each one with three repetitions and 270 rainbow trout with an average weight of 100±10 g were cultured with a density of 30 in per cage for 56 days. Based on the results, there were significant differences between mean weight, body weight gain, feed conversion ratio, specific growth rate and condition factor in all three treatments (P<0.05). However, there was no significant difference in terms of survival rate and body chemical composition between treatments (P>0.05). In general, the results showed that the third treatment (5% fish oil and 5% canola oil) in the diet improved the growth indices, survival rate and condition factor (P<0.05).