Culture and development of a harpacticiod species in different salinity and temparature

Abstract

Copepods play a major role as food link for larger animals and it is also important as a live food source for the aquaculture industry. There are only few reports of the influence of temperature and salinity towards the growth and development of copepods. In this study, two physical parameter, temperature (5 and 25 °C) and four different salinity regime (5, 10, 25 and 35 ppt) was used to determine the growth and population development in a marine harpacticoid, Pararobertsonia sp. in a laboratory condition. The findings shows that there was a significant difference (P<0.05) detected between the salinity treatment and it shows that different salinities have different effects on the population number of the copepod cultured in the same temperature (ambient, 25 ± 1 °C). Whereas for copepods reared in cold temperature ( 5 ± 1 °C), no observation was made and the copepods did not survive the very low temperature. Copepods reared in 25 ppt salinity show the highest population density that can be achieved at one time with 3.7 individuals per milliliter. However, copepods in 35 ppt treatment shows the most stable population growth among the others. From this experiment, it can be concluded that 35 ppt and ambient temperature (25 ± 1 °C) is the optimum condition for the maximum production of Pararobertsonia sp. in the laboratory condition.