Zaleha Kassim
International Islamic University
Malaysia
Title: Life cycle of a benthic harpscticoid in Laboratory condition and effect of some environmental factors on population growth
Biography
Biography: Zaleha Kassim
Abstract
Copepods are recently reported as a potential live feed to be used to replace our dependency on Artemia and rotifers in larviculture activity. Nonetheless, the number of the identified copepod species which potentially been use for mass production is still very limited.This study was carried out to determine the development time and sizesof the different stage of a marine harpacticoid copepod, Amphiascoidesneglectus cultured in laboratory condition. Theirpopulation growth when cultured in the different temperature, pH and salinity were also monitored. The culture was started with 50 adults in the sex ratio of 1:1 and the gravid females were observed until the end of egg-hatching period. Total development time between NI and CI stage is 63.67 ± 1.15hours (2.66 ± 0.05days) while between CI and adult stage is 89.97 ± 3.06hours (3.74 ± 0.13days). The size of naupliar stages varies from 53.86µm to 112.12µm (width) and 97.52 µm to 178.24 µm (length) and copepodite stages from 226.25 µm to 492.12 µm. The size of adult for male and female is 579.58µm and 593.98µm respectively. The highest population density is found in the combination of 28 °C, pH 9 and 25ppt culture condition (45.34 ± 5.54individual/ml). Naupliar production is highest in the treatment of 25 °C, pH 9 and 25 ppt (15.00 ± 2.00 individual/ml). The highest copepoditesand gravid females density is found in 28 °C, pH 9 and 25ppt which is 15.67 ± 1.53 individual/ml and3.67 ± 0.58 individual/ml respectively.The maximum specific growth rate, K is 0.1472 ± 0.0012. This study suggests that the optimum condition for the population growth of A. neglectuscould possibly at temperature 28 °C, pH 9 and salinity 25 ppt.