Tavares-Dias et al. (2001) described a Trichodina sp. Prevalence at fee fishings from Southeast Brazil. The authors also observed that Leporinus macrocephalus, P. mesopotamicus and Cyprinus carpio were the most susceptible species to the protozoa infestation, if compared to tambacu (P. mesopotamicus × Colossoma macropomum),Brycon cephalus, Tilapia rendalli and O. niloticus.