Comparative susceptibility of veliger larvae of four bivalve mollusks to a Vibrio alginolyticus strain

Abstract

The susceptibility of 7 d old veliger larvae of the scallops Argopecten ventricosus and Nodipecten subnodosus, the penshell Atrina maura, and the Pacific oyster Crassostrea gigas to a pathogenic strain of Vibrio alginolyticus was investigated by challenging the larvae with different bacterial concentrations in a semi-static assay. The results indicate that the larvae of the 2 scallop species are more susceptible to the V. alginolyticus strain than those of the oyster and the penshell. Signs of the disease were similar to bacillary necrosis described in previous work. Interspecies differences in susceptibility to pathogens are discussed.KEY WORDS: Vibrio alginolyticus · Pathogenicity · Vibriosis · Mollusks · Scallops · Pacific oyster · Penshell Resale or republication not permitted without written consent of the publisherDis Aquat Org 49: [221][222][223][224][225][226] 2002 metabolites) of the immune system in adult Mytilus edulis are also present in the trochophore and veliger larvae of this species (see review of Dyrynda et al. 1995). Recently, Mitta et al. (2000) found that synthesis of the antimicrobial peptide mytilina occurs during metamorphosis of larvae of Mytilus galloprovincialis, and the antimicrobial peptide defensin is detected when metamorphosis is finished.In the present paper, veliger larvae of 4 bivalves, comprising 2 scallops (Argopecten ventricosus and Nodipecten subnodosus), a penshell (Atrina maura) and the Pacific oyster (Crassostrea gigas) were challenged with different concentrations of Vibrio alginolyticus selected from several strains of the same and other species (V. tubiashii, V. parahaemolyticus, V. vulnificus and V. campbelli) tested in 24 h bioassays on veliger larvae of A. ventricosus. V. alginolyticus was isolated during bacterial screening in a shrimp hatchery. MATERIALS AND METHODS Bacteriology.A Vibrio alginolyticus strain named APSA2 was isolated from a hatchery of white shrimp (Farfantepenaeus vannamei) postlarvae, in La Paz, Baja California Sur, Mexico, during bacterial screening. The isolate was identified as V. alginolyticus by Dr. John McInroy at Auburn University, Alabama, USA. The strain was kept in Luria-Bertani medium (LBM) containing 3% NaCl and stored at 4°C until needed. For the susceptibility assays, liquid bacterial cultures were prepared in trypticase soy broth (TSB) (Difco). To find the optimum salinity for bacterial growth, a preliminary assay was run by inoculating the strain into TSB media containing 0.5, 2.0, 5.0, and 10.0% NaCl. Cultures were incubated at 28°C, and growth was estimated by reading absorbance of the cultures in a Spectronic Genesys 2 spectrophotometer at 580 nm, and at 0, 2, 4, 8, 10, and 24 h from inoculation. With these results (Fig. 1), bacterial cultures were subsequently prepared in 2% NaCl TSB.Bivalve larvae. Adult Argopecten ventricosus, Nodipecten subnodosus, Atrina maura, and Crassostrea gigas, were brought to the hatchery at Centro de Investigaciones Biologicas del Noroeste, La Paz, and were conditioned for spawning...

Efecto de bacterias probióticas en el cultivo larvario del ostión de placer Crassostrea corteziensis (Bivalvia: Ostreidae)

“…Sin embargo, al igual que en otros bivalvos, la alta mortalidad que se presenta durante la etapa larvaria y juvenil, es el principal problema que limita el desarrollo del cultivo en el laboratorio. Las mortalidades de C. corteziensis, son generalmente provocadas por bacterias del género Vibrio como ocurre también en Argopecten purpuratus (Riquelme et al 1995), A. ventricosus, Nodipecten subnodosus y Atrina maura (Luna-González et al 2002), C. virginica (Elston & Leibovitz 1980, Gómez-León et al 2008, C. gigas (Sugumar et al 1998, Luna-González et al 2002, Pecten maximus (Lambert et al 1999), Ruditapes philippinarum (Borrego et al 1996, Abasolo-Pacheco et al 2009). …”

Population‐specific genotype x genotype x environment interactions in bacterial disease of early life stages of Pacific oyster larvae

“…Interestingly, this temperature‐dependent disease resistance disappeared at the Pediveliger stage. In particular, Pacific oyster larvae are hypothesized to have a strong innate immune system that has a faster maturation rate in contrast to other marine bivalves (Luna‐Gonzalez, Maeda‐Martinez, Sainz, & Ascencio‐Valle, ). Thus, we hypothesize that in Pediveliger larvae the maturation of the immune system has reached a stage where temperature has no significant effect on defence capabilities anymore.…”

New Insights into Pathogenic Vibrios Affecting Bivalves in Hatcheries: Present and Future Prospects

“…Indeed, they demonstrated its virulence for larvae of M. mercenaria , O. edulis , A. irradians and T. navalis . Luna-González et al (2002) reported that scallops ( Argopecten ventricosus and Nodipecten subnodosus ) were more susceptible to the pathogen than other species tested, including Atrina maura and C. gigas , whereas Gómez-León et al (2005) demonstrated the virulence of V. alginolyticus for carpet shell clam ( Ruditapes decussatus ) larvae and spat. On the other hand, Estes et al (2004) associated the degree of virulence, at least for C. gigas , with an increase in the water temperature.…”