So far there have been some studies on breedings of a few species of copepoda but such a study had difficulty because of lack of suitable diet or requirement of a great deal of running water.
By the present study the authors have found that mass reproduction of a microplankton,
Tisbe furcata (body length, about 1mm) would be possible with feeding seawater-acclimatized chlorella as a basic diet.
A couple of living
T. furcata was put into 100m
l of chlorella suspensions in glass receptacles (200m
l) without aeration and we observed how the couple would multiply in the receptacles. The chlorella was
Chlorella ellipsoidea.
The density of the organism in the suspension was 0.5 ?? 1.0×10
7m
l in number of cells and the number of
T. furcata was counted every 5 days under different temperature (15, 20 and 25°C) and chlorinity (Cl=15, 17, 19 and 21‰) conditions for 40 days and 30 days respectively.
As result of the observation, the highest reproduction of
T. furcata was shown under temperature 25°C, wherein the number of
T. furcata became as many as 276 at the peak of 20 days, but higher survival rate of
T. furcata was shown under temperature 15°C in 40 days than under 20°C and 25°C.
As for the chlorinity of the suspension,
T. furcata breeded under all the conditions of 15-21‰ (S=27.10 ?? 37.93‰) in the experiments but the optimal chlorinity for the survival of
T. furcata seemes to be 15-19‰ (S=27.10 ?? 34.32%).
In the subsequent experiments the authors found that the optimal numbe of cells of chlorella to be used for the reproduction of
T. furcata would be about 0.5 ?? 1.0×10
7/m
l as the authors had tried originally.
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