SPAWNING OF CULTURED CORAL TROUT, Plectropomus leopardus

First generation (F1) of cultured coral trout has been successfully spawned in tanks. This study aimed to evaluate the quality of natural spawning of cultured coral trout. Observation was conducted on 30 of coral trout F1 broodstocks, body weight 2-4 kg and for a comparison, on 30 of wild coral trout broodstocks, body weight 2-5 kg. Both cultured and wild broodstocks were confined in 2 tanks (each tank for each type of broodstock) with approximately 300 % of water exchange. Broodstocks were fed fresh pilchard fish and squid mixed with Vitamin C and E. Feeding was performed once a day, ad libitum. Parameters observed were number of eggs produced, number of fertilized eggs, fertilization rate and spawning frequency.

The results of observation for 1 year showed that coral trout F1 spawned 6 times, with number of eggs produced ranged from 220,000 to 2,670,000 and fertilization rate was 41.15-85.16 %. While wild broodstocks (F0) were spawned 9 times with number of eggs produced ranged from 4,160,000 to 49,349,000 and fertilization rate was 60.97-85.16 %. To sum up, the quality of eggs produced by cultured coral trout was not as good as those produced by the wild one.