title: Presence and histopathological effects of the Parvatrema sp. (Digenea, Gymnophallidae) in the stout razor clam Tagelus plebeius (Bivalvia, Psammobiidae).
abstract: The stout razor clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray's fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout razor clam T. plebeius from Brazil.
authors.affiliation: Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Departamento de Biologia Celular, Embriologia e Genética, Laboratório de Imunologia Aplicada a Aquicultura, CEP 88040-900 Florianópolis, SC, Brazil. mirella_dasilva@hotmail.com
authors.forename: Patricia Mirella
authors.initials: PM
authors.lastname: da Silva
authors.forename: Florencia
authors.initials: F
authors.lastname: Cremonte
authors.forename: Rachel Costa
authors.initials: RC
authors.lastname: Sabry
authors.forename: Rafael Diego
authors.initials: RD
authors.lastname: Rosa
authors.forename: Liege
authors.initials: L
authors.lastname: Cantelli
authors.forename: Margherita Anna
authors.initials: MA
authors.lastname: Barracco
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000469:parasitology*; D001938:Brazil; D016054:DNA, Protozoan; D056890:Eukaryota; D006790:Host-Parasite Interactions / Q000502:physiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011529:Protozoan Infections, Animal / Q000453:epidemiology / Q000473:pathology*
chemical_list: D016054:DNA, Protozoan