L'ELEVAGE DE LA PALOURDE, PROGRAMME NATIONAL DE RECHERCHE SUR LA MALADIE DE L'ANNEAU BRUN

A national program started in 1989 to drive researches, on Ruditapes philippinarum brown ring desease cor elated with a vibrio called PI. The researches have concerned epidemiological surveys on spats and adults, treatment methods, diagnostic techniques, and anatomical and functional studies about the vibrio-clam relations. The transmissions of the desease appeared mainly related to contaminated manila clam seeds, with secondary horizontal propagation. The brown ring formation appeared to be caused by a periostracum deterioration. Taking into account some of these results, an adapted cultural technique including special care of seeds and decreased densities was proposed to the farmers.