Trypanosomatids (Protozoa: Kinetoplastida) in three species of Armored Catfish from Mogi-Guaçu river, Pirassununga, São Paulo, Brazil

Abstract

Trypanosome infections have been reported in several species of fish, in majority of cases described on the basis of morphological characteristics. Trypanosomes in fish are heteroxenous and transmitted by hirudineans. This study aims to evaluate the prevalence and density of infections by Trypanosoma sp. in blood from three species of catfish, Hypostomus regani, H. strigaticeps, H. albopunctatus, from the Mogi Guaçu River, Pirassununga, São Paulo, Brazil. Further, this study intends to characterize the Trypanosoma specimens found in the blood of these fish by morphological and molecular techniques. The trypanosomes overall prevalence observed was 47.6% with a general average density of 0.75 parasites/µl of blood. Hypostomus regani and Hypostomus strigaticeps showed a significant difference in prevalence. The average densities of parasites were not significantly different among the three fish species. Similar findings were observed for the monthly variations in densities. The parasites found in the three species of catfish studied showed similar morphological characteristics. The morphological data and the statistical analyses used in this study didn't show the formation of groups. The analyses provided evidence of the presence of pleomorphisms in the trypanosomes found in the three studied fish.Keywords: Trypanosoma, fish, Hypostomus, catfish, protozoa. ResumoInfecções por tripanossomas foram descritas em diversas espécies de peixes, sendo a maioria das descrições baseada nas características morfológicas. Tripanossomas de peixes são heteroxenos e transmitidos por hirudíneos. Este estudo tem como objetivo a avaliação da prevalência e densidade da infecção por Trypanosoma sp. no sangue de três espécies de cascudos, Hypostomus regani, H.strigaticeps, H.albopunctatus, do Rio Mogi-Guaçu, Pirassununga, São Paulo, Brasil. Além disso, pretende-se a caracterização das espécies de Trypanosoma encontradas no sangue desses peixes, por meio da utilização de técnicas morfólogicas e moleculares. A prevalência total de tripanossomas foi de 47,6%, e a densidade média foi de 0,75 parasitas/ µl de sangue. Hypostomus regani e Hypostomus strigaticeps apresentaram diferenças significativas em prevalência. As médias das densidades dos parasitas não apresentaram diferenças significativas entre as três espécies de peixes estudadas. O mesmo foi observado com a variação mensal das densidades. Os parasitas encontrados nas três espécies de cascudo possuíam características morfológicas semelhantes. As análises morfológicas e estatísticas obtidas neste estudo não mostraram a formação de grupos. As análises evidenciaram a presença de pleomorfismo dos tripanossomas encontrados nas três espécies de peixes estudados.

Trypanosomiasis causing mortality outbreak in Nile tilapia intensive farming: Identification and pathological evaluation

“…Numerous articles have described the morphology of trypanosomes in freshwater fish (Grögl et al, 1980, Pádua et al, 2011, Reda, 2011Fujimoto et al, 2013;Molina et al, 2016), including hosts of the genus Oreochromis (Davies et al, 2005); however, the morphometric results found in this study indicated that there is no similarity with previous studies. This variance among studies may be due to the great diversity of trypanosome species and to the pleomorphism of these parasites (Gibson et al, 2005).…”

“…In South America, reports of trypanosomiasis are common in several armored fish species (Eiras et al, 1989;Eiras et al, 1990;D'Agosto and Serra-Freire, 1993;Fujimoto et al, 2013;Lemos and Souto-Padrón, 2014;Lemos et al, 2015;Molina et al, 2016;Corrêa et al, 2016), Petenia kraussii (Grögl et al, 1980), catsharks (Morillas et al, 1987;Silva et al, 2005), and in tuvira (Pádua et al, 2011), highlighting that in all these cases, the hosts are wild fish. The most relevant reports of trypanosomiasis in farmed fish are related to groupers in China (Chong, 2005;Su et al, 2014;Wang et al, 2015), and to our knowledge, only Hamid and Babiker (2011) have reported Trypanosoma infections in cultured Nile tilapia Oreochromis niloticus (Sudan).…”

Morphometric Characterization of Trypanosoma spp. and blood parameters in Pterygoplichthys pardalis (Pisces: Loricariidae) from the Brazilian Amazon

“…However, few blood manifestations have been identified in species of Loricariidae (Fujimoto et al 2013, Corrêa et al 2016. Additionally, it is suggested that fish that recover from infection by these hemoparasites can become immune against possible reinfection (Molina et al 2016). The aim of the present study was to describe infection by Trypanosoma spp.…”

“…Trypanosoma spp. are heterozygous parasites that spend one phase of their lives in the bloodstream of different species of aquatic vertebrates (fish, amphibians and reptiles) and another stage in the intestines of leeches, which infect fish populations on several continents (Corrêa et al 2016, Molina et al 2016, Lapirova & Zabotkina 2018, McAllister et al 2019. The trypomastigote forms of these parasites have a more or less elongated morphology, notably in the nucleus, kinetoplast, undulating membrane and flagellum (Eiras et al 2010).…”

“…This shape appears to be based on the level of digestion of the blood ingested, with the trypomastigote appearing only when the blood is fully digested. This characteristic is also influenced by the temperature and amount of blood ingested (Molina et al 2016).…”