Factors inducing fertility in aseptic Crustacea
© Biologischen Anstalt Helgoland 1970
1. Fertility stops after a few aseptic generations in cultures ofArtemia salina, Tigriopus japonicus andDaphnia magna fed algae.
2. Fertility was restored in amphigonic and parthenogeneticArtemia salina subjected to low-salinity stress by addition of milligram concentrations of yeast and liver extract.
3. Fertility ofTigriopus japonicus andDaphnia magna was restored by addition of vitamin mixtures to the algae/crustacean medium.
4. The vitamins act directly on the algae by increasing their nutritional value for the crustaceans cultivated.
5. Continuous aseptic culture ofMoina macrocopa was obtained in an artifical medium enriched with egg yolk and vitamins E and D. Such a medium supports only 5 to 6 generations ofDaphnia magna.
6. Lipid factors seem essential for sustained fertility inMoina macrocopa andDaphnia magna.
7. Some suggestions are made for improving partially gnotobiotic cultures of filter-feeders.