Two Perkinsus spp. infect Crassostrea gasar oysters from cultured and wild populations of the Rio São Francisco estuary, Sergipe, northeastern Brazil.
Brazilian production of bivalve molluscs is small but expanding, especially in the northeastern region where the native oysters Crassostrea rhizophorae and C. gasar are abundant, and tropical weather promotes their rapid growth. Studies on bivalve pathology are scarce in Brazil, with only a few employing techniques for detecting protozoan pathogens listed by the World Organisation for Animal Health (OIE). In 2008, a Perkinsus sp. was reported for the first time in Brazil, infecting C. rhizophorae oysters from a wild population in Ceará state, NE Brazil. Recently P. marinus was detected in the same oyster species in nearby Paraíba state. These findings highlighted the need to expand knowledge on the presence and impacts of Perkinsus spp. on Brazilian oyster populations. The current investigation evaluated Perkinsus sp. infections among wild and cultured C. gasar mangrove oysters from the estuary of the Rio São Francisco, Sergipe state, NE Brazil. Our results show that Perkinsus sp. infections occurred commonly in oysters of both groups, at prevalences that were frequently higher among cultured oysters. Prevalences varied seasonally, with maximum values during summer (January) of 57% and 80% for wild and cultured oysters respectively, and minimum values during winter (July). Results of DNA sequencing, in situ hybridization assays, and phylogenetic analyses showed dual- and single-pathogen infections by P. marinus and/or P. olseni in the tested oysters.
Núcleo de Engenharia de Pesca, Universidade Federal de Sergipe, CEP 49100-000 Aracajú, SE, Brazil; Departamento de Biologia Molecular, Universidade Federal da Paraíba, CEP 58051-900 João Pessoa, PB, Brazil. Electronic address: mirella_dasilva@hotmail.com.
Patricia Mirella
PM
da Silva
Embrapa Tabuleiros Costeiros, Bairro Jardins, Caixa Postal 44, CEP 49025-040 Aracajú, SE, Brazil. Electronic address: mscardua@hotmail.com.
Marcos Paiva
MP
Scardua
Núcleo de Engenharia de Pesca, Universidade Federal de Sergipe, CEP 49100-000 Aracajú, SE, Brazil. Electronic address: rtvianna@gmail.com.
Rogério Tubino
RT
Vianna
Núcleo de Engenharia de Pesca, Universidade Federal de Sergipe, CEP 49100-000 Aracajú, SE, Brazil. Electronic address: raoani@hotmail.com.
Raoani Cruz
RC
Mendonça
Departamento de Biologia Molecular, Universidade Federal da Paraíba, CEP 58051-900 João Pessoa, PB, Brazil. Electronic address: cairebarreto@gmail.com.
Cairé Barreto
CB
Vieira
Maryland Department of Natural Resources, Cooperative Oxford Laboratory, 904 S. Morris Street, Oxford, MD 21654, USA. Electronic address: cdungan@dnr.state.md.us.
Christopher F
CF
Dungan
Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, VA 23062, USA. Electronic address: gpscott@vims.edu.
Gail P
GP
Scott
Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, VA 23062, USA. Electronic address: kreece@vims.edu.
Kimberly S
KS
Reece
D000818:Animals; D016782:Apicomplexa / Q000235:genetics*; D001938:Brazil; D049896:Crassostrea / Q000382:microbiology*; D016054:DNA, Protozoan / Q000032:analysis; D063366:Estuaries; D017404:In Situ Hybridization, Fluorescence; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction
D016054:DNA, Protozoan
Crassostrea gasar; Histopathology; Oysters; Perkinsus marinus; Perkinsus olseni; rDNA