Mulata spawning analysis in 2005 and 2006
The comparison of Mulata spawning in 2005 and 2006 as below. Wild captured G. nigra are rearing at UNAPDCM since 2002 and it starts spawned from 2002. Seven females (biomass 14,056 g) spawned 9,551,611 eggs with 83 times spawning under water temperature 15.8 ± 0.89 ° C from July 13 to November 1, 2005 . Spawned egg consist 6,956,117 floating eggs (72.8%) and it produces 4,487,154 hatch-out larvae (64.5%). Six females (biomass 13,035 g) spawned 15,657,954 eggs with 94 times under 16.5 ± 0.63 ° C from June 11 to October 17, 2006 . Spawned egg consist 7,947,405 floating eggs (50.8%) and it produces 5,422,681 hatch-out larvae (68.2%). G. nigra spawn several times in a spawning season and the spawning quantity per fish body weight shows 679,500 eggs/Kg in 2005 and 1,202,224 eggs/Kg in 2006. The strong relation shows between egg quantity and the average water temperature while 3 days before spawning and it abundant at WT 15.50 ° C in 2005. It has more spawning quantity at 16 ° C...