Copepods are a highly valued live prey item for larvae of marine finfish but u ntil recently the controlled production of copepods for use in aquaculture has been scarce and small in scale. CFEED, a private company headquartered in Trondheim, Norway, has pioneered larviculture techniques to effectively produce Acartia tonsa year-round and offer a steady supply of eggs which can be delivered to hatcheries around the world. The population of copepods at CFEED, however, remains essentially wild and less effort has been made to improve production through selective breeding. Fecundity in calanoid copepods has been reported to be a highly heritable trait but there exist few examples of mult i-generational breeding for increased egg production in these species.
In order to explore the potential of breeding to increase the egg production of female copepods, a selection program was initiated that systematically measured daily egg production for females, individually, over 7 days . Females with the highest average daily production of eggs were then selected for crossing into the next generation via a partitioned mass spawn design. Subsequent generations were reared in a similar fashion, selecting females at random from the mass spawned pool of juvenile copepods.
Initial results suggest that selection for fecundity produced rapid changes in the mean egg production of copepods between generations . The extent to which these substantial gains can continue to be improved at this rate remains to be determined, as well as whether increased egg production is a physiological trait with trade-offs in other performance metrics. Nevertheless, these findings suggest that selective breeding could be a valuable tool to increase the efficiency of commercial copepod farming. After several generations, egg production traits will be compared to an unselected population of copepods in a common environment to evaluate estimates of genetic gain.