Effects of dietary supplementation with different vegetable lipid sources on growth, feed utilization and meat quality in rainbow trout (Oncorhynchus mykiss W., 1792)

In this study, the effects of dietary supplementation with different vegetable lipid sources on the growth (live weight gain, relative growth rate, daily spesific growth rate, condition factor, hepatosomatic index and vicerosomatic index), feed utilization (feed intake, feed conversion ratio, protein efficiency ratio, protein productive value, apparent digestibility ratios of nutrients and energy in the experimental feeds) and chemical quality of meat (crude protein, fat, fatty acids, ash, fiber, nitrogen free extract, moisture and total energy) of rainbow trout (Oncorhynchus mykiss) were investigated.For this purpose, control and experimental diets 1, 2, 3, 4 and 5 were prepared at the lipid ratio 17% used fish oil, soybean oil, sunflower oil, corn oil, cotton seed oil and hazelnut oil, respectively. Three replicates were conducted for each trials. Feeding rate was calculated as the feeding coefficient and percentage of the live weight was given to fishes three times in a day during 3 months at 12±2 oC of water temperature.At the end of this study, there was a significant differences between experimental groups in the live weight gain, relative growth rate, daily spesific growth rate, feed conversion ratio, protein efficiency ratio and hepatosomatic index values (p<0.05). On the other hand, there was not determined significant differences between the condition factor, feed intake, protein productive value, viserosomatic index, apparent digestibility ratios of crude protein, fat, ash, fiber and energy in the experimental diets and the feed costs for 1 kg fish produce (p>0.05). In addition, there was a significant differences between the crude ash, fiber, nitrogen free extract, n-3 and n-6 series fatty acid values in the fish meat of the experimental groups and n-6 series fatty acid values in the fish liver (p<0.05) but these relations were not significant for the crude protein, fat, moisture and total energy in fish meat, and n-3 series fatty acid values in the fish liver (p>0.05).Under the light of this study, it is concluded that it is possible to use a certain amount of soybean oil, sunflower oil, corn oil or hazelnut oil instead of fish oil in rainbow trout diets but cotton seed oil is not suitable to use.Keywords: Rainbow trout (Oncorhynchus mykiss), vegetable lipid sources, growth, feed utilization, chemical quality of meat, digestibility of nutrient and energy.