have been reared for a period of seven and 14 years,
respectively, in 150 tonnes of cylindrical fiber
reinforced plastic (FRP; 8 m in diameter and 3 m in
height), equipped with a recirculation system. Both
types of brood fish were fed with enriched prey fish
(Sardinella sp.), and supplemented with pure cod liver
oil (Seven seas, Merck Company), every two days
until satiation. The salinity was maintained at 29.5 to
31.4 ppt; the water temperature was 27.0 to 28.8 oC;
the dissolved oxygen was 6.09 to 7.02 mg/l; and the
pH was 7.81 to 8.21.
For egg collection purposes, female hybrid
groupers OGGG (weighed at 16.2 kg) were treated
with the Human Chorionic Gonadotrophin (HCG)
hormone twice in March 2014. The dosage was 250
IU/ kg for each injection. The first injection was given
on 26th March 2014, followed by the second injection