A new low cost microtest with the freshwater ciliate protozoan Spirostomum ambiguum. Definition of culturing conditions

Culturing conditions for Spirostomum ambiguum were examined for 2 French strains collected from pond locations and a Polish strain that had been in laboratory culture for several years. The strains were grown in natural and reconstituted waters maintained at different conditions of temperature and light and with several types of inert diets. One of the French strains was found to be the best for stock culture and maintenance. The best culture conditions in terms of survival and reproduction were obtained using reconstituted Volvic water at 20C and a diet of oat flakes supplemented with dried leaf powder. Medium and food were renewed weekly. These culture conditions gave an average generation time of 4 d. There are 30 references.