M Afsharnasb - Iranian Fisheries Research Organization, Tehran, Iran
A Matinfar
Mohammad Mohamadydost
A Ghavampoure

Objective: The importation of Litopenaeus vannamei to Iran from Hawaii was occurred when Iranian shrimp culture faced with white spot syndrome virus (WSSV) in 2004. To introduce this species, experimental study was carried out on the effects of different stocking densities on growth rate, survival rate, food conversion ration and the total harvest of L. vannamei in the Iranian shrimp culture industry. Method & Materials: Three postlarval group (PL12) of L. vannamei (Pond A: 20 PL/m2, Pond B: 30 PL/m2 and Pond C: 50 PL/m2) with an average size, 0.9cm and initial mean weight, 0/015g±0/005 were used in this study. The experiments were carried out in triplicate in 9 half hectare of earthen pond located in Choiebde site in Khuzestan Province in the south of Iran for 110 days. The survival rate, FCR, total harvest and growth rate were determined by Brock and Main (1994) method. The salinity, temperature, pH and DO measured routinely. Results & Conclusion: The result showed that there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture in this study. Mean survival rate among farms were greatest at the lowest density, where mean survivals in pond A was 88.6%, Pond B was 83% and Pond C was 80%, respectively, however, the difference was not significant (P>0.05). The results also showed there was no significant difference (P>0.05) on growth rate/10days in each experiment where the mean growth rate/10days for Pond A calculated 1.96 g for Pond B 1.85g and for Pond C 1.73g, respectively. The food conversion ration at the end of the study for Pond A was 1.01, for Pond B was 1.17 and for Pond C was 1.2. Shrimp production increased linearly with an increase in stocking density when farm production at Pond A and Pond B indicated insignificant change (P>0.05) with pond C. The total production was calculated for Pond A 3280 kg/he, for Pond B 4156 kg/he and for Pond C 5670 kg/he, respectively. This study suggests that L. vannamei could adapt to Iranian shrimp culture industry

Litopenaeus vannamei, Stocking density; Growth rate; Survival rate; Food conversion ratio; Total harvest