عنوان مقاله [English]
This study was conducted to improve the feeding of Huso huso in completely randomized design in fiberglass tanks with a capacity of 1100 L under identical conditions. 300 juvenile Huso huso (215±10g) were distributed to 15 tanks each containing 20 fishes. Water flow rate was 20±2L/min with the water temperature of 15±0.4ºC and the dissolved oxygen content 7.7±1mg/L during the experiment. The experimental fish were fed manually 3 times daily according to 1-2 % of body weight and depending on their apetite which lasted for a period of six weeks. The water was supplied with non-circulated filtered from a river. Five experimental diets with various levels of lipid were formulated: D1 (without added oil), D2 and D3, diet of soyabean oil (with levels, 5/35% and 17/4%, respectively), D4 and D5, diet of fish oil (with levels, 5/35% and 17/4%, respectively). At the end of the experiment, there were noticeable improvements in fish growth following the addition of different fat level in the diets. The increased fat content in the fish feed resulted in better FCR, BWI and SGR. The lowest level of cholesterol was observed in fish that were fed with D5 diet. There also appeared no significant difference in triacyl glycerol among treatments. In general, with respect to FCR, BWI, and SGR, D5 diet proved better results of growth. This can be attributed to a greater palatability of the diet which contained higher fish oil as well as to its better physiological effects.