The propagation of L. vannamei shrimp, selected brooders of different generations

We used Molokai and High health broodstocks for inbreeding and cross-breeding of them. For water security, in the first step Persian Gulf water with a pump pure in the concrete laver and then transfer in the two smaller laver, and disifected with 50 ppm calcium hypochlorite in the priod of 12-24 hours, and then transferred to the ultrafilter and ultra violet before transfer to the hatchery. Broodstocks were stocked at the density of 8-10 ind/m^2 in the 4 metric tons fiber glass tank. The feeding of broodstocks were done 4 times at the 9, 11.30, 14 and 20. 3. Three times with cuttlefish (Sepia pharaonis) and sand worm (Perinereis nuntica) and 1 time with edible bivalve meat (Solen brevis) and cow livier. Maturation and mating of broodstocks was done in the 4 cubic meters round fiberglass tanks with the diameter of 2.4 m and 1 m height. For spawning of broodstocks we used tanks with 300 liters content with the diameter of 0.9 m at the head and 0.7 m at the base and in the 4 cubic meters fiber glass tank. Rearing of larvae were done with natural (Chaetacerous sp.) and artificial diet. The amount of dissolved oxygen, water tempreture, pH and salinity measured daily. In the end of initial propagation period, in the inbreeding of High health 3600 Pl16 and from Molokai no obtained any postlarvae. In the cross-breeding of female High heaith×male Molokai 1500 Pl7 and from female Molokai × male high health 1350 Pl21 were produced. In the second year, in the propagation of female Molokai×male High health, 600 thousands of Pl12 was obtained. In the end of initial propagation period, only the survival of female Molokai×male High health was suitable. Therefore in the second year, we only propagate this one. The better propagation of broodstocks in the second year, was mainely due to use of live and fresh freeze perinereis nuntica worm and probably better broodstocks genetic characteristic. The mean temperature, oxygen and pH of water measured 28.75±2.33, 28.16±1.30 0 C, 6.51±0.60 and 7.360± 0.46 mg/land 8.81±0.03 and 8.15±0.20. The salinity of water maintained at 32±2 PPT.