Molecular data and the evolutionary history of dinoflagellates

Nutritional strategies in dinoflagellates: A review with emphasis on cell biological aspects.

Diseases caused by parasites in the aquaculture of warm water fish

https://onlinelibrary.wiley.com/doi/epdf/10.1111/raq.12365

Sustainable aquaculture requires environmental-friendly treatment strategies for fish diseases

The present work relates diagnosticated cases of fish diseases in the state of Sao Paulo, Brazil between January/1999 and December/2000. During 1999, the monogenean was the most important parasite (72.9%), followed by Piscinoodinium pillulare (43.2%), Henneguya piaractus (34.2%), Ichthyophthirius multifiliis (23.4%) and copepodids of Lernaea cyprinacea (9.0%). However, in 2000, monogenean showed 78.9%, trichodinids 52.1%, P. pillulare 35.7%, I. multifiliis 29.8% and L. cyprinacea 11.9%. The most infected fish was Piaractus mesopotamicus, followed by Leporinus macrocephalus, hybrid "tambacu" and Oreochromis niloticus. This work showed the highest susceptibility of "tambacu" and L. macrocephalus to P. pillulare and P. mesopotamicus to monogenean Anacanthorus penilabiatus. The authors emphasize the importance of prophylaxis in farmed-fish, as well as adequate transport and water quality. The regular accompaniment of fish health, strategic applications of sodium chloride in the water and vitamin C supplementation in the ration to avoid the unbalance of the host/parasite/environment system.

Recent studies on parasitic infections of freshwater cultivated fish in the state of Sao Paulo, Brazil

. Trophonts of Pisdnoodinium pillulare (Schaperclaus, 1954), a common ectoparasite of freshwater aquarium fish, are attached to host cells by means of a specialized structure, the attachment disc. Unlike other dinoflagellate genera parasitic on fish and invertebrates, this disc features nail-like organelles, the rhizocysts. Head-parts of the rhizocysts are inverted in separate compartments, rhizothecas, in the sole of the disc while their long shafts are firmly embedded in the cytoplasm of cells of the host epidermis or gill epithelium. The attachment inflicts a serious injury on the host cells which may ultimately be destroyed. Rhizocysts originate in the subnuclear cytoplasm from where they migrate into the attachment disc. There are other specialized organelles and inclusions; fibrous vesicles, membraneous bodies, striated tubular bodies and paracrystalline bodies. Pisdnoodinium has well-developed chloroplasts. While its cytological adaptations indicate a nutritional dependence on the host, there is no evidence of ingestion of host-derived particulate material. Pisdnoodinium may derive an essential part of its nutrition from photosynthesis.

G. Schubert

Papers

Ultrastructural study of Pisdnoodinium pillulare (Schäperclaus, 1954) Lom, 1981 with special emphasis on its attachment to the fish host