Development of Khawia sinensis Hsü, 1935 (Cestoda: Caryophyllidea) in the fish host.

The development of the tapeworm Khawia sinensis has been observed up to the stage of sexually mature parasites releasing eggs in an experimentally infected definitive host (Cyprinus carpio) at 15-16 degrees C. Juvenile, maturing, adult and gravid tapeworms were found 2-12, 19-24, 36-62, and 78-91 days post infection, respectively. No apparent size difference between tapeworms from carp kept at 20-22 degrees C, examined 1-16 days post infection, and those from 15-16 degrees C was observed. In naturally infected and fed carp, kept at 21-22 degrees C, some tapeworms survived till the end of experiment (44 days) while in unfed fish they survived only 15 days from the beginning of experiment.