Effect of poultry waste oil as a source of dietary fat on growth performance and Fat accumulation in the liver tissue in Rainbow trout (Oncorhynchus mykiss)

To investigate the feasibility of using poultry waste oil as an energy source in rainbow trout (Oncorhynchus mykiss) diets, an experiment designed by a completely randomized plan with three treatments and three replications for each treatment in a semi-closed aquaculture system, with an average temperature of 19.1±2.11°C (Mean±‌ SD). The experimental units consisted of fiberglass tanks with a useful volume of 100 liters by 1.5 liter per minute water replacing. Fattened fish weighted average 21.67±0.38 g were fed for eight weeks, with three of the same chemical composition and different fat sources diets (including 100% fish oil (control), 50% of poultry waste oil and 50% fish oil (treatment 1) and 100% of poultry waste oil (treatment 2)). The results of the experiment, showed significant difference in final weight, protein efficiency ratio, established protein, rate of muscle protein, condition factor, SGR and FCR between the experimental groups. Usage of treatment by 50% replacement led to fish in this experimental group, compared with the other groups on measures such as: feed conversion ratio, established protein, specific growth rate and condition factor was significantly superior (p>0.05). Overall findings indicate that the combined use of fish oil and poultry waste oil with equal proportion can be a good way to provide energy and fatty acids for rainbow trout.