Characterization of actin genes in Bonamia ostreae and their application to phylogeny of the Haplosporidia

SUMMARYBonamia ostreae is a protozoan parasite that infects the European flat oyster Ostrea edulis, causing systemic infections and resulting in massive mortalities in populations of this valuable bivalve species. In this work, we have characterized B. ostreae actin genes and used their sequences for a phylogenetic analysis. Design of different primer sets was necessary to amplify the central coding region of actin genes of B. ostreae. Characterization of the sequences and their amplification in different samples demonstrated the presence of 2 intragenomic actin genes in B. ostreae, without any intron. The phylogenetic analysis placed B. ostreae in a clade with Minchinia tapetis, Minchinia teredinis and Haplosporidium costale as its closest relatives, and demonstrated that the paralogous actin genes found in Bonamia resulted from a duplication of the original actin gene after the Bonamia origin.

Download Full-text

Localization and characterization of acid phosphatase activity in Bonamia ostreae (Ascetospora), an intrafemocytic protozoan parasite of the flat oyster Ostrea edulis (Bivalvia)

Diseases of Aquatic Organisms ◽

10.3354/dao012067 ◽

1992 ◽

Vol 12 ◽

pp. 67-70 ◽

Cited By ~ 15

Author(s):

D Hervio ◽

D Chagot ◽

P Godin ◽

H Grizel ◽

E Mialhe

Keyword(s):

Acid Phosphatase ◽

Phosphatase Activity ◽

Acid Phosphatase Activity ◽

Protozoan Parasite ◽

Ostrea Edulis ◽

Bonamia Ostreae ◽

Flat Oyster

Download Full-text

Infection with the protozoan parasite Bonamia ostreae modifies in vitro haemocyte activities of flat oyster Ostrea edulis

Fish & Shellfish Immunology ◽

10.1016/j.fsi.2009.03.018 ◽

2009 ◽

Vol 26 (6) ◽

pp. 836-842 ◽

Cited By ~ 37

Author(s):

Benjamin Morga ◽

Isabelle Arzul ◽

Bruno Chollet ◽

Tristan Renault

Keyword(s):

Protozoan Parasite ◽

Ostrea Edulis ◽

Bonamia Ostreae ◽

Flat Oyster

Download Full-text

Establishment of an experimental infection protocol for the flat oyster, Ostrea edulis, with the intrahaemocytic protozoan parasite, Bonamia ostreae: application in the selection of parasite-resistant oysters

Aquaculture ◽

10.1016/0044-8486(94)00342-l ◽

1995 ◽

Vol 132 (3-4) ◽

pp. 183-194 ◽

Cited By ~ 39

Author(s):

D. Hervio ◽

E. Bachère ◽

V. Boulo ◽

N. Cochennec ◽

V. Vuillemin ◽

...

Keyword(s):

Experimental Infection ◽

Protozoan Parasite ◽

Ostrea Edulis ◽

Bonamia Ostreae ◽

Flat Oyster ◽

Selection Of

Download Full-text

Population bottleneck and effective size in Bonamia ostreae-resistant populations of Ostrea edulis as inferred by microsatellite markers

Genetics Research ◽

10.1017/s0016672301005353 ◽

2001 ◽

Vol 78 (3) ◽

pp. 259-270 ◽

Cited By ~ 45

Author(s):

SOPHIE LAUNEY ◽

MARC BARRE ◽

ANDRE GERARD ◽

YAMAMA NACIRI-GRAVEN

Keyword(s):

Protozoan Parasite ◽

Population Bottlenecks ◽

Effective Number ◽

Ostrea Edulis ◽

Effective Number Of Breeders ◽

Temporal Variance ◽

Bonamia Ostreae ◽

Flat Oyster ◽

Two Populations ◽

Future Management

Genetic variability at five microsatellite loci was analysed in three hatchery-propagated populations of the flat oyster, Ostrea edulis. These populations were part of a selection programme for resistance to the protozoan parasite Bonamia ostreae and were produced by mass spawns, without control of the genealogy. Evidence for population bottlenecks and inbreeding was sought. A reduction in the number of alleles, mainly due to the loss of rare alleles, was observed in all selected populations, relative to the natural population from which they were derived. Heterozygote excesses were observed in two populations, and were attributed to substructuring of the population into a small number of families. Pedigree reconstruction showed that these two populations were produced by at most two spawning events involving a limited number of parents. Most individuals within these populations are half or full-sib, as shown by relatedness coefficients. The occurrence of population bottlenecks was supported by estimates of effective number of breeders derived by three methods: temporal variance in allelic frequencies, heterozygote excess, and a new method based on reduction in the number of alleles. The estimates from the different methods were consistent. The evidence for bottleneck and small effective number of breeders are expected to lead to increasing inbreeding, and have important consequences for the future management of the three O. edulis selected populations.

Download Full-text

Comparison of diagnosis techniques for the protozoan parasite Bonamia ostreae in flat oyster Ostrea edulis

Aquaculture ◽

10.1016/j.aquaculture.2006.05.014 ◽

2006 ◽

Vol 261 (4) ◽

pp. 1135-1143 ◽

Cited By ~ 22

Author(s):

Pablo Balseiro ◽

Ramón Fernández Conchas ◽

Jaime Montes ◽

Javier Gómez-León ◽

Beatriz Novoa ◽

...

Keyword(s):

Protozoan Parasite ◽

Ostrea Edulis ◽

Bonamia Ostreae ◽

Flat Oyster

Download Full-text

A non-lethal method for detection of Bonamia ostreae in flat oyster (Ostrea edulis) using environmental DNA

Scientific Reports ◽

10.1038/s41598-020-72715-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Louise von Gersdorff Jørgensen ◽

Johan Wedel Nielsen ◽

Mikkel Kehler Villadsen ◽

Bent Vismann ◽

Sussie Dalvin ◽

...

Keyword(s):

Water Samples ◽

Sea Water ◽

Diagnostic Technique ◽

Environmental Dna ◽

Detection Methods ◽

Ostrea Edulis ◽

Breeding Programs ◽

Bonamia Ostreae ◽

Flat Oyster ◽

Selection Of

Abstract Surveillance and diagnosis of parasitic Bonamia ostreae infections in flat oysters (Ostrea edulis) are prerequisites for protection and management of wild populations. In addition, reliable and non-lethal detection methods are required for selection of healthy brood oysters in aquaculture productions. Here we present a non-lethal diagnostic technique based on environmental DNA (eDNA) from water samples and demonstrate applications in laboratory trials. Forty oysters originating from Limfjorden, Denmark were kept in 30 ppt sea water in individual tanks. Water was sampled 6 days later, after which all oysters were euthanized and examined for infection, applying PCR. Four oysters (10%) were found to be infected with B. ostreae in gill and mantle tissue. eDNA purified from the water surrounding these oysters contained parasite DNA. A subsequent sampling from the field encompassed 20 oysters and 15 water samples from 5 different locations. Only one oyster turned out positive and all water samples proved negative for B. ostreae eDNA. With this new method B. ostreae may be detected by only sampling water from the environment of isolated oysters or isolated oyster populations. This non-lethal diagnostic eDNA method could have potential for future surveys and oyster breeding programs aiming at producing disease-free oysters.

Download Full-text