Generation Time of Some Marine Harpacticoid Species in Laboratory Condition

Recent investigations on harpacticoid copepods have demonstrated their higher nutritional values compared to Artemia and rotifer. Nevertheless, studies on the potential use of tropical harpacticoid copepods as live feed in aquaculture are still limited. The present study was carried out to compare the generation time between selected harpacticoid species cultured in laboratory condition as an early step to choose a potential live feed for aquaculture practices. Some estuarine species of harpacticoids were isolated from Merchang river mouth, an estuary of the South China Sea in Terengganu and undergone trial culture procedure. Three species (Paradactylopodia oculata, Schizopera knabeni and Robertsonia knoxi) were successfully adapted to the laboratory condition thus their generation time were recorded. Copepod samples were cultured under controlled laboratory condition at temperature 25±1°C and salinity 27±1 ppt for 40 days and fed with 0.1 mL of baker’s yeast (0.02 g/L/day). The mean generation time (day) was different for each species where P. oculata showed the long generation time (17.19±4.74 days) followed by S. knabeni (10.19±3.51 days) and R. knoxi (8.93±1.00 days). The species with short generation times could be a better choice for fish larval rearing and hatchery activity due to the early time of nauplii production and hence we suggest the R. knoxi could be used as a potential live feed (on the basis of their generation time) in aquaculture practices.