QU ALITY IMPR OVEMENT OF DISQU ALIFIED TIGER PRA WN (PENAEUS MONODON FAB.) BROODST OCK USING DOP AMINE

Disqualified tiger prawn broodstock has undergone ablation after two breeding periods, which causes high production cost, pollution of environment and difficulties in providing the broodstock continuously with enough quantity at an exact time. The purpose of this study was to find the proper dosage of dopamine to improve the quality for breeding of the disqualified tiger prawn, because dopamine inhibits maturation, so there will be enough time for maturation and improvement of the eggs quality. This experiment used 15 pairs of the twice breeding tiger prawn, which was collected from -9 Perigi (Central Java). The samples were treated with different dosages of dopamine (dosage 10, -8 -7 -6 10, 10, 10 moll and control/injected with aquabidest). The parameters identified in this experiment w ere duration (da ys) for eg gs maturation, fecundity , fertilizing rate , hatching rate, egg diameter and phototaxis response of the nauplii. The research concluded that the average duration for eggs maturation on the broodstock -9 -8 -7 -6 that were injected with dopamine, dosage 10, 10, 10, 10 moll and control, were 14, 12, 4, 2, 5 days, respectively. Fecundities were 561.489, 503.000, 384.205, 230.850 and 150.034. Fertilizing rates were 89.8%, 82.1%, 56.0%, 46.3%, and 23.2%. Hatching rates were 79.53%, 72.53%, 47.75%, 12.27%, and 36.6%. Diameters were 0.29; 0.29; 0.29; 0.27; and 0.27 mm. The nauplii