EXPERIMENTAL VIBRIOSIS INDUCTION WITH VIBRIO-ALGINOLYTICUS OF LARVAE OF THE CATARINA SCALLOP (ARGOPECTEN-VENTRICOSUS = CIRCULARIS) (SOWERBY-II, 1842)

Six-day-old larvae of the catarina scallop, Argopecten ventricosus (=c ircularis), were infected with different concentrations of Vibrio algi nolyticus to determine virulence and to describe vibriosis in this spe cies. The development of vibriosis was compared to the effect of the s upernatant of a 24-h V. alginolyticus culture. An experimental larvae culture system (ELCS) yielded a maximum survival of 80% from the 6th t o the 19th day (control and low concentrations of V, alginolyticus). N o effect was shown with concentrations of V. alginolyticus below 0.5 x 10(5) CFU ml(-1). At concentrations higher than 5.0 x 10(5) CFU ml(-1 ), swimming depletion, empty stomachs, lipidic granules in the digesti ve system, velum degradation, and massive mortality were observed. The supernatant of V. alginolyticus culture showed similar effects to the highest concentrations of V. alginolyticus cells.