Etude de la dynamique du parasite Marteilia refringens au sein de la population tunisienne de moules Mytilus galloprovincialis et l’huître perlière Pinctada radiata.

Abstract

The search for other potential hosts for the Marteilia refringens parasite and Elucidating the life cycle of this parasite is a priority in the management of the risk of marteiliosis. The detection of the M. refringens in the oyster O. Stentina, in Tunisia, enlarges the host range and geographical distribution of this parasite, which appears to be capable to infecting a wide range of bivalve species. For this reason, we selected two species that coexist with the Ostrea stentina oyster in order to study the transmission of the parasite to the other species which forming part of the ecosystem studied; The mussel Mytilus galloprovincialis and the pearl oyster Pinctada radiata. The PCR analysis targeting the ITS-1 region, was based on samples which have a positive results for universal PCR. The amplification products obtained were presented with multiple bands. Subsequently, a second PCR of a total of 180 individuals was analyzed firstly by the MT1 / MT2 PCR and subsequently by a second MT1B / MT2B PCR. Of 90 individuals of P. radiata and 90 individuals of M. galloprovincialis tested, no individuals were detected positive for infection by the parasite Marteilia refringens. Finally, the hypothesis of M. refringens infected the potential intermediate hosts, M. galloprovincialis and P. radiata is rejected. Based on our results, only O. stentina should be included in the list of susceptible species of M. refringens infection.