title: Cyrilia sp. (Apicomplexa: Haemogregarinidae) in the Amazonian freshwater stingray Potamotrygon wallacei (cururu stingray) in different hydrological phases of the Rio Negro.
abstract: Intraerythrocytic parasites are frequently found in fish, including elasmobranchs. The Amazonian rivers present well defined annual hydrological cycles that results in drastic modifications of the environmental conditions with deep implications in the life cycle of the whole associated biota in those fluvial systems. The freshwater stingray Potamotrygon wallacei (stingray cururu) is a new species restricted to the Middle Rio Negro basin and it is subject to strong alterations in their natural habitats (igapós) a result of the constant variations in the water level of Rio Negro. This work demonstrates the occurrence of intraerythrocytic parasite Cyrilia sp. in this stingray species. Additionally, the prevalence and quantification of hemoparasites in different phases of Rio Negro were also established. Field sampling was carried in the Archipelago of Mariuá, Middle Rio Negro, involving different stages of the water cycle. The intraerythrocytic parasites were quantified by direct counting in blood smears using a total counting of 2000 erythrocytes in each blood smear. The presence of parasites intraerythrocytic generates changes in the morphology of blood cell. The largest amount of the hemoparasites was recorded in the drought period. We observed a decreasing tendency in the number of parasites in the blood between the drought periods and inundation. We concluded that the level of Negro River influences the incidence of intraerythrocytic parasites in the cururu stingray and the drought represents the period of larger susceptibility to the infestation.
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia do Amazonas - IFAM, Campus Manaus Centro, Avenida 7 de Setembro, 1975, CEP 69020-120, Manaus, AM, Brazil.
authors.forename: A T
authors.initials: AT
authors.lastname: Oliveira
authors.affiliation: Universidade Federal Rural de Pernambuco - UFRPE, Campus Recife, Avenida Dois Irmãos, s/n, CEP 52171-900, Recife, PE, Brazil.
authors.forename: M L G
authors.initials: MLG
authors.lastname: Araújo
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia do Amazonas - IFAM, Campus Presidente Figueiredo, Avenida Onça Pintada, 1308, CEP 69735-000, Presidente Figueiredo, AM, Brazil.
authors.forename: J
authors.initials: J
authors.lastname: Pantoja-Lima
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia do Amazonas - IFAM, Campus Manaus Distrito Industrial, Avenida Danilo Areosa, 1672, CEP 69735-690, Manaus, AM, Brazil.
authors.forename: P H R
authors.initials: PHR
authors.lastname: Aride
authors.affiliation: Empresa Brasileira de Pesquisas Agropecuárias - EMBRAPA, Rodovia Juscelino Kubitschek, Km 5, CEP 68903-419, Macapá, AP, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Tavares-Dias
authors.affiliation: Department of Biological Sciences, Florida International University - FIU, 3000 NE 150 St. 33181, Miami, FL, USA.
authors.forename: R P
authors.initials: RP
authors.lastname: Brinn
authors.affiliation: Laboratório de Ciências Fisiológicas, Universidade Federal do Amazonas - UFAM, Avenida General Rodrigo Octávio Jordão Ramos, 3000, CEP 69077-000, Manaus, AM, Brazil.
authors.forename: J L
authors.initials: JL
authors.lastname: Marcon
mesh_terms: D000818:Animals; D001938:Brazil / Q000453:epidemiology; D003044:Coccidia / Q000302:isolation & purification*; D003048:Coccidiosis / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D004912:Erythrocytes / Q000469:parasitology; D005393:Fish Diseases / Q000453:epidemiology* / Q000469:parasitology; D045483:Rivers; D012860:Skates, Fish