Effects of organophosphorus insecticides: effects of trichlorfon and dichlorvos on the immune response of carp (Cyprinus carpio). III. In vitro effects on lymphocyte proliferation and phagocytosis and in vivo effects on humoral response.

Cells isolated from the pronephros of carp were incubated in vitro with the organophosphorus insecticide trichlorfon or dichlorvos, each of which is used in aquaculture to eliminate fish ectoparasites. Dose-dependent suppressive effects were observed in assays for lymphocyte proliferation and myeloid cell respiratory burst activities. Dichlorvos given by bath in vivo did not affect antibody production against Yersinia ruckeri even if the spleen and kidney were obviously contaminated according to acetylcholinesterase activity analysis. Some blood parameters of nonspecific immunity (ceruloplasmin, lysozyme, hemagglutinins) were slightly affected.