Growth and survival rates, mean weight, food conversion ratio and total harvest in cultured Shrimp Litopenaeus vannamei in Iran

To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of L. vannamei. Mee post-larval groups (P1,12) of L. vannamei (pond A: 20 PL/m2, pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, 0.16g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P