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

Abstract

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.   Key words: Disqualified,  dopamine, dosage, duration. maturation, fecundity, fertilizing, hatching, diameters, nauplii