Effect of Vegetable Protein and Oil Supplementation on Growth Performance and Body Composition of Russian Sturgeon Juveniles (Acipenser gueldenstaedtii Brandt, 1833) at Low temperatures*

摘要

Effect of different feed compositions on growth performance and body composition of Russian sturgeon (Acipenser gueldenstaedtii) juveniles was studied. One control and three experimental diets were prepared with different ratios of soybean meal (20%, 10.5%, 33%, and 27%) sunflower meal (7%, 8.5%, 14.5%, and 10.5%) and corn meal (10%, 20.5%, 15% and 7.5%) substitute fish meal (40%, 35%, 25%, and 30%) as a protein source. Corn oil (2.5% in Group I and 10% in Group II) and sunflower oil (2.5% in Group I and 10% in Group III) also were substituted for fish oil (10% in control group and 5% in Group I) as a lipid source. Initial weight of fish was 143.89±2.84 g, following the feeding time the fish reached 67.92±1.90 g in the control group, and 1= 62.73±2.11 g, 2= 55.09±2.57 g and 3= 59.74±2.34 g in experimental groups, respectively (P≤0.05). Feed conversion ratio was found 2.57 in control group, 2.75, 3.06 and 2.86 in experimental groups, respectively and differences between the groups were found significant (P≤0.05). Hepatosomatic index and viscerosomatic index were significantly different (P≤0.05) between the initial and the final values of feeding trials. No differences were determined between the experimental groups (P≥0.05). Condition factors and specific growth rate were similar before and following the feeding trials in experimental groups. According to the body composition, crude protein and crude fat levels in the fish body were affected by the feeds (P≤0.05). Decreased protein level in the feed (Group III) resulted in poor protein level in the fish body. Crude fat in the fish body was similar in first (fish oil) and third (sunflower) group, but fat deposition in the body and liver of fish were higher in second (fish oil 5% + corn oil 2.5% + sunflower oil 2.5%) and third (corn oil 10 %) group. After the feeding trials, liver fat levels were similar whereas the fat levels of the liver were different from initial liver fat (P≤0.05) values of the other groups. Fish body and liver fat values were similar in control (fish oil) and Group III (sunflower oil) but different in the other groups (P≤0.05).