TREATMEN OF SHRIMP FARM SOURCE  WATER TO ELIMINATE CRUSTACEAN VECTOR OF VIRAL  DISEASES WITH DICHLORVOS

Of the several methods for eliminating crustacean vectors of shrimp disease from shrimp ponds, treatment with Dichlorvos appears to be the most effective and economical. This compound degrades quickly, and there is no detectable residue in water 5 to 7 days after application at 3 mg/L. Shrimp from ponds subjected to the standard Dichlorvos treatment used at shrimp farmers (in Lampung, Indonesia), did not contain Dichlorvos residue after 90-106 days of culture, 10-14 days days before the normal time of harvest. No residue also found in ponds water and the mud (bottom substrate). The production rate is also considered to be normal, with the SR varies from 64.3% - 79.7%. Having   ADG of about 0.16 - 0.22g/day the shrimp  could reach the MBW of 15.53 - 24.92 g/indv, and the production reach 3,779 kg - 8,247 kg/5000 m2 (depend on its stoking density). There does not appear to be any reason for food safety concerns related to Dichlorvos use at the farms, for a residue of this compound does not occur in shrimp. Dichlorvos degrades completely after 7 days at treatment rates used at farms. Thus, there is no opportunity for discharge of Dichlorvos via pond effluent into natural waters. The compound is toxic to hum ans, for that workers should follow instruct tions as provi ded, such as protective clot hing, and proper equipment to allow safe us.