The effect of water physicochemical factors of culture ponds on the survival rate of Litopenaeus vannaemi in shrimp culture farms of Abadan-Choebdeh

This study was performed to survey the relationship between water physicochemical factors and determination the effective parameters on Litopenaeus vannaemi survival in three ponds of three different farms with same stocking (250000 pl) and same storage time during 109 days (Days of culture), from June to September, in shrimp culture ponds of Abadan-Choebdeh. The results showed that the highest correlation between salinity and temperature, as well as salinity and pH is established. Nitrate and phosphate values ​​recorded during the culture period were outside of the standard range. The results of correlation between chemical feature and survival showed in all of three farms, the nitrate and ammonia had the maximum effect on shrimp survival which this relationship was expressed inverse. According to the results, the mean of primary weight, final weight and weight gain was observed in T3 more than T1 and T2 , and survival rate in T3 and T2 was more than T1 at the end of the culture period. It seems that the level of protein in diets play an important role in the nitrate and ammonia scale and finally in survival.