Effect of partial harvesting strategies on Artemia biomass production in Vietnamese salt works

摘要

The effect of partial harvest strategies on the production of Artemia biomass was evaluated for 12 weeks under Vietnamese salt farm conditions. The initial stocking density was 100 nauplii L−1. After 3 weeks of inoculation, Artemia adults were partially harvested at intervals of 1, 3, 6 and 9 days starting with an initial quantity of 30 kg ha−1 day−1 at first harvest, and then the quantity of harvestable biomass was adjusted according to the standing stock present in the culture pond, combined with the time needed to harvest these quantities and with the weight of biomass harvested in each pond. The results showed that in most cases, the total densities were not significantly different among harvesting frequencies (P0.05). However, a relatively higher Artemia adult density and its standing stock were better maintained in the 3-day than in the 1-day interval, and were significantly higher compared with the other two harvesting frequencies. The total biomass yields were the highest (1587 kg ha−1) in the 3-day harvesting interval, followed by 1-, 6- and 9-day harvesting interludes, corresponding to 1323, 1091 and 975 kg ha−1 respectively. However, no statistical difference was observed between the 1- and the 3-day interval as well as between the 6- and the 9-day harvest schemes (P0.05). The results of this study suggest that partial harvest of Artemia biomass performed every 3 days appears to be an appropriate strategy to enhance biomass productivity.