Investigation of the effects of interaction dietary energy levels in fresh water and brackish water of (Caspian Sea) on growth, survival and body composition of Astacus leptodactylus

Experiment was conducted for 8 weeks to determine the reaction (Astacus leptodactylus) to interaction energy and salinity. Diets containing 3 levels of energy (300,370 and 450 kcal/100g) with a constant protein content of 30% and 2 levels of salinity (fresh water and brackish water (12 ppt) were formulated. Tank content 110 liter, each filled with 80 liter water. 5 A.leptodactylus (average weight of 17±2) were storage per each tank and feed twice a day. Results showed different levels of energy did not have significant effect on growth factor and survival of crayfish (P< 0.05), but fresh water and brackish water had a significant effect on growth factor. The best growth was seen in fresh water. Survey on interaction between energy –salinity was indicated the highest growth were seen in (fresh water) and energy 370 (kcal/100g). Caracas analyzes (protein and lipid) in treatment salinity decreased and has a significant (P<0.05) effect. The highest protein carcass was seen in interaction between energy (370 kcal/100gr) and (0 ppt) which had significantly different with other treatments (P<0.05). The greatest amount protein of body composition were in practical diet containing 370 kcal/100gr energy and fresh water which had significantly differences with other treatment (P<0.05). Overall this study indicates the dietary which containing 370 kcal/100gr energy in fresh water has the greatest performance on growth, nutrition and body composition.