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This study was conducted on farmed Acipenser nudiventris at the International Sturgeon Research Institute from the winter of 2007 till summer 2010. A total of 11 farmed A. nudiventris specimens (7 male and 4 female) were stocked in groups of 4 fish in eight fiberglass tanks (4 tons capacity) on the basis of their sex. Males were fed with a diet with no soybean but containing vitamins. Females were fed with a diet containing soybean and vitamins with 38-40% protein, 13-15% fat, 19.5-20Mj/kg energy, respectively. GnRH was used for artificial propagation of Acipenser nudiventris brood stocks twice for females (dose 10μg/kg with 80:20 ration) and during one occasion for males with a dose of 20 μg/kg. The results of the study indicated that food composition (soybean and vitamins C and E) played a significant and positive role in the reproduction system for females. No significant effect of treatment was observed in Testosterone levels between mature (Mean ±SD: 60.6±8.07ng/ml) and immature (24.42±4.87ng/ml) males, Likewise, no significant differences were found in17α-Hydroxy Progestrone for female (Mean ±SD: 0.106±0.019ng/ml) and for immature fishes (0.031±0.006ng/ml) significant differences was detected in the concentration of Albomine (1.54±0.05mg/dl for females and 1.35±0.07mg/dl for immature females), but there were no significant differences in other biochemical parameters including Glocose, Cortisol, Chlosterole and Triglisride in males and females. There were no significant differences in total weight and length, WBC, RBC, Hb, Hct, MCH, MCHC and MCV parameters in males and females. This study is a step forward towards the development of artificial breeding and rearing sturgeon fish in the country.

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In this study, a total of 60 juvenile Acipenser persicus (mean weight 410±267.6, mean length 39.6±19.6 cm and 1 - 2 year old) were captured by trawling method at depths of 20 to 100 meters in the Mazandran province via 7 times surveys during 2009 – 2012, and studied immunologically. Results showed that the mean of red blood cells (RBC) and white blood cells (WBC) were 585000 ± 151000 and 30300 ± 3200 per mm3 of blood, respectively. Mean percentage of lymphocyte, monocyte, neutrophile and eozynophile were 83.1 ± 12, 2.9 ± 2, 8.3 ± 6.6 and 5.6 ± 3.2 %, respectively. Mean concentration of Immunoglobin M (IgM) in blood serum was 25.6 ± 8.7 mg/dl. Samples showed no significant difference in length (P>0/05). These results showed that the fish by less than the length classes were more sensitive to environmental changes. For this reason, their immune indices improved. Therefore, any change in fish blood immunological factors can lead to the secondary response.