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

Abstract

The present work relates diagnosticated cases of fish diseases in the state of São 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.