Reproductive and growth performances in female giant freshwater prawn following inhibition of gonadal maturation using dopamine and medroxyprogesterone hormone

ABSTRACT One of the main problem in giant river prawn (GFP) culture is early gonadal maturation in female resulting a reduced growth performance. This problem cause economic losses. When GFP at gonadal maturation, somatic growth will be inhibited because energy is used for reproduction. A factorial experimental design using two factors, namely dopamine and medroxyprogesterone, with each factor consist of three levels was applied. Three dopamine levels were 0, 10-5 mol/shrimp, and 10-10 mol/shrimp, while the medroxyprogesterone levels were 0, 75 mg/1.5 mL/bodyweight, and 150 mg/3 mL/bodyweight with a density 15 individual/tank. The utilization of dopamine and medroxyprogesterone in GFP (initial bodyweight : 11.27 ± 0.97 g) through injection at the third periopod was done three times at week 0, 2nd, and 4th with two weeks interval. The results showed that hormone inhibitor treatments affected both growth and reproductive performances in female GFP. The treated individuals showed a lower gonadal maturity indicator values and faster growth rate than control. Gonadal maturity, as shown by gonad histology, in all treatments were lower (previtelogenic and vitellogenic stages) than that in control which is in mature stage. Estradiol concentration premix dopamine 10-10 mol/shrimp and medroxyprogesterone 150 mg/3 mL/bodyweight treatments are lower than control. In conclusion, dopamine and medroxyprogesterone administration could suppres GSI and gonad development, and also increase growth rate. Keywords: Macrobrachium rosenbergii, dopamine, medroxyprogesterone, gonad development, growth.