The Effect of Stocking Density on Growth and Stress Indices of Fingerlings and Juvenile Acipen serbaerii Reared in Fiberglass Tanks

Inroduction & At this time,Acipen serbaerii reared in fiber glass tanks to batten period in Iran, while we don’t have any study about stocking density optimum beforebatten period for Acipen serbaerii. aim of this study determined to survey effect of Stocking density on growth factors and stress hormones of fingerling and juvenile Acipenserbaerii reared in fiberglass tanks.
Material and In first and second study 700, 1000 and 1300 individuals with average weight of 2.93±0.083 gr were released to 9 fiber glass tank with stocking density of 0.5, 0.75 and 1 kg/m2and 350, 500 and 750 individuals with average weight of 9.31±0.18 gr with initial stocking density 0.8, 1.3 and 1.9 kg/m2were released in same tanks with three replicates. Fish fed in 3 feeding time to 5and 4 percent of body weight (BW) daily, respectively. In the end of feeding period, we received blood sample by syringe and measured cortisol hormone by Radioimmunoassay, while cholesterol and Glucose was measured by Spectrophotometry.
In first study (3gr), increasing of stocking density had significant decreasing on growth parameters, increasing of feed efficiency ratio and stress hormones, but in second phase increasing of stocking density don’t afford significant increase for stress hormones but growth parameters significantly decreased in fish reared in highest stocking density (1.9 kg/m3).
Result of this study indicated that Acipenserbaerii(3-9gr) have a sensitive to increasing of stocking density, but when fish reach to9 gr have higher tolerance against density and therefore possibility rearing of fish in high density were accessible.