QUALITY IMPROVEMENT OF DISQUALIFIED TIGER PRAWN (Penaeus monodon Fab.) BROODSTOCK USING DOPAMINE

Disqualified tiger prawn broodstock is the one that has undergone ablation after two breeding periodes, which causes high production cost, pollution of environment and difficulties in providing it continuously with enough quantity at exact time. The purpose of this study is to find the proper dosage of dopamine which will give good quality for breeding of the disqualified tiger prawn, because dopamine inhibits maturation, so it has enough time for maturation and can be improved the eggs quality. This experiment used 15 pairs the twice breeding tiger prawn, which is taken from Perigi (Central Java). The sample were treated with difference dosage of dopamine (dosage 10-9 , 10-8, 10-7, 10-6 moll and control/injected by aquabidest). The parameters were identified in this experiment are duration (days) for eggs maturation, fecundity, fertilizing rate, hatching rate, egg diameter and phototaxis respnnsive of the nauplii. The result of this research are the of the average of duration for eggs maturation on the broodstock that were injected dopamine, dosage 10-9 , 10-8, 10-7, 10-6 moll and control , were 14, 12, 4, 2, 5 days. Fecundity 561.489, 503.000, 384.205, 230.850 and 150.034. Fertilizing rate 89,8 %, 82,1 %, 56.0 %, 46,3 %, and 23,2 %. Hatching rate 79,53%, 72,53%, 47,75%, 12,27%, and 36.6% . Diameter 0,29; 0,29; 0,29; 0,27; and 0,27mm. The nauplii that had produced by injected broodstock by dosage 10-9 , 10-8, 10-7, have the positive phototaxis responsive while dosage 10-6 and control were weak.