Mutual effect surveys of culture density, temperature and water volume on feed consumption, food conversion ratio and growth of rainbow trout (Oncorhynchus mykiss)

Being succeed in aquaculture is mainly dependents on environmental and cultural conditions. Density, temperature and water flow are the most important factors that influence water quality and aquatic conditions. This study conducted to evaluate the effects of mentioned factors on feed consumption, food conversion ratio and growth of rainbow trout (Oncorhynchus mykiss). According to the Response Surface Methodology (RSM), at a 60 day trial, 1400 fry (mean weight 10±1.5) exposed in different water flow (0.1, 0.2 and 0.3 l.s-1), density (50, 70 and 90 individuals) and temperature (10, 15 and 20 oC) and fed by commerical diet. At the end of trial, food intake, food conversion ratio and weight gain optimized according to the objected factors. After data analysed, results revealed that food intake affected by different densities (P<0.05) but temperature and water flow did not affect significantly (P>0.05). Food conversion ratio and growth significantly affected by density and water flow (P<0.05); but Water temperature did not affect on this factors (P>0.05). According to this experimental conditions 170 fish.m-3, 0.9 l.s-1 of water flow and temperature of 15 oC, will achieve best food intake, food conversion ratio and growth.