Growth, mortality and susceptibility of oyster Crassostrea spp. to Perkinsus spp. infection during on growing in northeast Brazil

Abstract

Crassostrea rhizophorae and C. gasar oysters are cultivated in the northeast region. Perkinsus parasites infect bivalves, and their effects on oysters from tropical regions are poorly understood. This study evaluated the impact of Perkinsus infection on the productive traits of native oysters. Oysters were sampled bimonthly during 7 months, from July 2010 to February 2011, to evaluate growth rate, mortality and shell color patterns (white and dark-gray) (n = 500), and to determine the prevalence and intensity of Perkinsus (n = 152). Perkinsus and Crassostrea species were determined using molecular tools. Results showed that most dark-gray (90%, n = 20) and white (67%, n = 18) oysters were C. gasar and C. rhizophorae, respectively. Oysters showed a high growth rate and moderate cumulative mortality (44%). C. gasar oysters grew better and showed lower mortality and lower incidence of Perkinsus compared to C. rhizophorae. The mean prevalence of Perkinsus was moderate (48%), but the infection intensity was light (2.2). Perkinsosis affected very small oysters (19.4 mm). In conclusion, native oysters, especially C. gasar, have a great potential for culture, mortality is not associated with perkinsosis, and the shell color of oysters can be used to improve selection for spats with better performance.

Perkinsus sp. infecting three important mollusks from Jaguaribe River estuary, Ceará, Brazil

“…In recent years, the prevalence of Perkinsus observed in oysters from different regions of the country has varied considerably and, although the value found in this study (8%) has been lower than that recorded in oysters from that same estuary in 2015 (17.3%) and in oysters from Carnaubeira River in Maranhão (10.6%), the same was higher than the values recorded in oysters from the estuaries of the Rivers Camurupim, in Piauí (5.3%) and Pacoti, in Ceará, in 2009and 2010. In other states of the northeastern region, the prevalence of Perkinsus recorded in the RFTM assays has been higher than the values mentioned above (Luz et al, 2018;Queiroga et al, 2015;Scardua et al, 2017;Silva et al, 2016). In the present study, the infection intensity ranged from very light to light (clams), very light to severe (oysters) and very light to moderate (mussels).…”

“…Since then, other studies have reported the occurrence of Perkinsus sp. in oysters of the genus Crassostrea from several regions (Brandão et al, 2013;Luz et al, 2018;Scardua et al, 2017). It is worth noting the record, in 2016, of the species P. chesapeaki, detected for the first time in South America, infecting oysters from the Jaguaribe River estuary, Ceará (Dantas et al, 2016).…”

EPIZOOTIOLOGY OF Perkinsus sp. INFESTING Crassostrea rhizophorae FROM THE SEMI-ARID REGION, BRAZIL

“…Two mangrove oyster species (Crassostrea rhizophorae and C. gasar) inhabit the estuaries of the Northeast region of Brazil (3) . The oyster C. rhizophorae is naturally found in estuarine environments along the Brazilian coast, fixed on substrates, mainly in the roots of mangroves (4) .…”

“…The oyster C. rhizophorae is naturally found in estuarine environments along the Brazilian coast, fixed on substrates, mainly in the roots of mangroves (4) . Mangrove oysters are produced using artisanal techniques, which include the sampling of naturally settled spats at different places in an estuary (3) .…”

Detecção de enterobactérias e vírus entéricos em frutos do mar no Estado de São Paulo

“…No Brasil, a produção de moluscos bivalves é significativa nos Estados de Santa Catarina, Espírito Santo e São Paulo (RISTORI et al, 2007). No ano de 2015, o Estado de Santa Catarina teve uma produção de 17.000 toneladas de mexilhões e 3.000 toneladas de ostras (SCARDUA et al, 2017), representando quase o total da produção nacional. No entanto, nas regiões Sudeste e Sul, foi observado um incremento de 19% e 21% na produção de moluscos, respectivamente.…”