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During 1999, Shahid Beheshti & Yousefpour hatcheries were released 6499769 fingerlings produced by 225 female spawners from 1999.5.28 to 1999.7.26. Totally 2458667 fingerlings released from Shahid Beheshti hatchery which consisted of 2360490 specimen of Acipenser persicus (96% frequency) with mean weight of 1.8 g and 7.6 cm length, 86177 specimen of Acipenser stellatus (3.5% frequency) with mean weight of 3.9 g and 11.2 cm length, 1200 specimen of Acipenser nudiventris (0.5% frequency) with mean weight of 3.6 g and 8.7cm length. Out of the total numbers of fingerlings released 82.4% of A. persicus, 45% of A. stellatus & 25% of A. nudiventris fingerlings were below 3g. The survival rate of A. persicus & A. stellatus were 33.7% and 32.0%, respectively. The result of study on growth coefficient and condition factor showed these fingerlings had low growth coefficient (4.89) and mean condition factor (04). In Yousefpour hatchery 4020002 sturgeon fingerlings were released consist of 3968262 specimen of A. persicus (99.4% frequency) with mean weight of 3.1 g and 8.9cm length, 51740 specimen of A. stellatus (0.6% frequency) with mean weight of 0.9g & 6.3cm length. Out of total number of released 61.7% of A. persicus and 100% Of A. stellatus were below 3g. The total Survival rate of A. persicus & A. Stellatus fingerlings were 46.3 and 28.4%, respectively. The experiments Showed that the growth coefficient and condition factor were low, 3.64 and 0.37, respectively. The results of comparing the mean quality of A. persicus between Shahid beheshti & Yousefpour (P0.05) showed that there is a significant difference among length, weight, condition factor & growth coefficient of these 2 hatcheries in a way that the fingerlings released from Yousefpour rearing and propagation center had better condition in terms of length and weight but, their growth coefficient and Condition factor were lower than A. persicus fingerlings in Shahid Beheshti hatchery.

WE sampled 139 specimen of Acipenser persicus and 103 Acipenser stellatus over the years 19984999 in five fishing zones of the southern Caspian Sea for heavy metal contamination assessment. Flame Atomic Absorption Spectrophotometery was used to determine contamination of the specimens with Zn, Cu, Cd, and Pb and cold vapor method for Hg. The mean age for A. persicus and A. stellatus was 17.6±2.6 years and 11.9±1.8 years, respectively. The mean concentrations of heavy metals assessed for dry weight of the muscle tissues and caviar in A. persicus were 26.9 and 65.9 µg/g for Zn, 1.8 and 4.2 µg/g for Cu, 0.61 and 0.111 µg/g for Pb and 0.61 and 0.005 µg/g for Cd. The wet weight concentration of Hg in the muscle tissue and caviar of the fish were 0.06 and 0.007 µg/g respectively. For A. stellatus we determined the mean concentration of heavy metals in dry weight of the muscle tissue and caviar to be 27.4 and 57.8 µg/g for Zn, 1.64 and 4.85 µg/g for Cu, 0.481 and 0.112 µg/g for Pb and 0.59 and 0.005 µg/g for Cd while the wet weight concentration of Hg were 0.05 and 0.008 µg/g. By international standards, the contamination of the muscle tissue and caviar samples with the heavy metals in the two sturgeon species are well below maximum allowable for human consumption.