Erythroid Elements of Hemolymph in Anadara kagoshimensis (Tokunaga, 1906) under Conditions of the Combined Action of Hypoxia and Hydrogen Sulfide Contamination

Abstract

The effect of the combined action of hypoxia (0.05 mg O₂/L) and hydrogen sulfide contamination (4–8 mg S^2–/L) on the morphometric characteristics of the bivalve mollusk Anadara kagoshimensis (Tokunaga, 1906) was studied under experimental conditions in vivo; the exposure lasted for 24 hours. A significant increase in the size of granular inclusions in cells was observed. The number of these granular inclusions increased by 72–178%, in comparison with the control values (normoxia). The volume of erythrocytes increased by 15–74% and reached 608.1 ± 15.2 μm³ in some individuals. The cells formed aggregates of different shapes and sizes against the background of pronounced poikilocytosis. A significant increase in the number of erythrocyte shadows became a mass phenomenon. Simultaneously, granular inclusions containing hematin entered into the hemolymph of the mollusk. It is assumed that these granular inclusions reacted with H₂S to form Fe₂S₃ and thus neutralized the toxic effect of hydrogen sulfide.