HISTOPATHOLOGICAL PROGRESSION OF HEMIC NEOPLASMS IN THE TROPICAL CRABPARATELPHUSA-HYDRODROMOUS (HERBST) TREATED WITH SUBLETHAL CADMIUM CHLORIDE

Tropical crab Paratelphusa hydrodromous were exposed in the laboratory to five sublethal cadmium chloride concentrations (0.02, 0.05, 0.25 a nd 0.50 muM/L) for 30 days to evaluate the cellular inflammatory and c hronic pathologic responses. The most frequent pathologic responses of hepatopancreas exposed to 0.25-0.50 muM CdCl2/L were atrophy of R-cel ls and the development of granulomatous reaction consisting of granulo cytes and monomorphic basophilic cells. Coagulative necrosis was evide nt in the young oocytes at 0.05 muM CdCl2/L which was accompanied by t he increased vitellophagia of follicle cells. Thirty-day exposure to 0 .25-0.50 muM CdCl2/L shortened the reproductive life span of the crabs by inducing spontaneous atresia and granulocytosis. Eosinophilic gran ulocytes, the most numerous cell type found in the necrotic centers, p hagocytosed the masses of cellular debris and yolk from cadmium-induce d atretic oocytes. The widespread proliferation of basophilic cells re lated to hyalinocyte with high nucleocytoplasmic ratio would suggest t he development of hemic neoplasia. Heavy granulocytic infiltration was the typical cellular inflammatory response during chronic pathologica l conditions.