Trichodinidae in commercial fish in South America

Abstract

Ciliates of the family Trichodinidae are protozoan parasites of importance for fish farming in South America, given that at high infestation levels, they cause significant mortality among farmed fish. Although data on economic losses due to parasitosis are not available for South America, mortality outbreaks correlated to trichodinids are very common in the tilapia production chain, especially in Brazil, the largest aquaculture chain in the country. In Brazil in the past, trichodinids were considered only as Trichodina sp. Today, they have been better studied and identified taxonomically in wild and farmed fish. However, in other countries in South America, trichodinids continue to be described only as Trichodina sp. This review presents the history of occurrences of trichodinids in fish of interest in South America, highlighting 15 new species that have been described in three genera in Brazil, along with information on parasite-host-environment relationships, diagnostic methods and treatments. The occurrence of parasitic ciliates must be correlated with farming conditions such as stress factors, water quality, seasonality, age and host immunity to elucidate the critical points of each production system. Furthermore, for tropical fish, studies on treatment against trichodinid species are needed to provide support for approval of antiparasitic medications for use in fish farming. However, it is recommended that the production sector use intensive production systems that are more sustainable, with biosafety protocols, to increase production and productivity.

Effects of anEnterococcus faecium‐based probiotic on growth performance and health of Pirarucu,Arapaima gigas

“…in their mucus and gills compared to other treatments. Trichodinids are recognized as one of the main fish parasites that are responsible for economic losses due to high mortality rates in fish farming (Maciel, Garcia, Chagas, Fujimoto, & Tavares‐Dias, ; Martins, Cardoso, Marchiori, & Pádua, ) and especially in mortality of pirarucu farming in conjunction with monogeneans, branchiura, protozoans and nematodes (Araujo et al, ; Marinho et al, ). The high mean intensity of trichodinids observed here in the experimental fish that did not receive feed that was supplemented with probiotics could have been the cause of higher mortality in these treatments.…”

Identification of parasites in youth paiches “Arapaima gigas”

“…Sin embargo, en otros países de América del Sur, los tricodinidos siguen siendo descritos sólo como Trichodina sp. (Maciel et al, 2017). Los brotes de Trichodiniasis pusieron en peligro la supervivencia de los peces en algunos estanques.…”

First report of Trichodinella and new geographical records of trichodinids in Nile tilapia (Oreochromis niloticus) farmed in Brazil

“…Trichodinids are mobile peritrichous ciliated protozoa that are important within marine and inland aquaculture. More than 300 species of trichodinids have been recognized as parasites or symbionts of aquatic organisms (GONG et al, 2005;MITRA et al, 2013;MACIEL et al, 2018). They are perhaps the most frequent protozoa invading the surface of fish and have been implicated in severe disease and mortality in various parts of the world (NIKOLIĆ et al, 2003;KHAN, 2004;KHOSHNOOD & KHOSHNOOD, 2014;VALLADÃO et al, 2014).…”