Responses of Unio pictorum to the Presence of Toxic and Nontoxic Strains of Microcystis aeruginosa

Abstract—In order to assess the impact of cyanobacteria on mollusks under experimental conditions, the interaction of toxic and nontoxic strains of the cyanobacterium Microcystis aeruginosa (Kützing) Kützing and bivalve mollusks Unio pictorum (Linnaeus, 1758) has been studied. Cyanobacteria have a negative effect on bivalve mollusks: the 40% death of mollusks and deterioration of their adaptive capacity are recorded when cocultivated with M. aeruginosa at a high cell concentration. At the same time, there is no difference in the mortality of mollusks incubated with toxic and nontoxic cyanobacteria. A decrease in the content of microcystin-LR in the presence of bivalves is revealed. No statistically significant increase in the number of cyanobacteria in the water is noted after transit passage through the digestive system of bivalves.