Immune Response of Sheep at Subchronic Intoxication by Pyrethroid Insecticide Supercypermethrine

Immune Response of Sheep at Subchronic Intoxication by Pyrethroid Insecticide Supercypermethrine.Acta vet.Brno, 61, 1992: 57-60.Testing of the influence of subchronic (6 weeks) load of sheep organism caused by the pyrethroid insecticide supercypermethrine on functionality of cells of the immune system was carried out.Insecticide was administered daily in molasses feed in the doses 50,200 and 300 mg .kg-1 of live weight.During the last two weeks (5th to 6th weeks) of the experiment we recorded a decrease of the phagocytic index dependent on the supercypermethrine dose.Percentage of E rosette forming cells and the migration index were either unchanged or displayed insignificant dose-dependent values. Pyrethroid insecticide, supercypermethrine, sheep, phagocytic acti7Jity, E rosette test, leucocyte migration indexOuter environment represents the source of a great number of different chemical factors influencing the immune response of humans and animals (Moore and Faith 1976).Many chemical preparations have been developed and applied in free nature during the recent decades.This refers most often to herbicides and insecticides.Their wide-area application brings along the toxicological hazards as well.Characteristics of pesticides from the viewpoint of their influence on animal health represents a highly topical aspect of the present.Besides the classical toxicological methods for testing of insecticide harmlessness, an important role is played by the immunological examinations which allow to detect even very moderate toxicological risk (V os et al. 1982; Desi et a1.1986).Presented study followed the influence of the pyrethroid insecticide supercypermethrine on cellular immune response of sheep.Synthetic pyrethroids represent a new group of insecticides.Cypermethrine (type II pyrethroid), m. w. 413.3, contains cyanide group (CN-) and its empiric formula is: C.' Huel NO. (Sapiets et a1.1984).It belongs among oral and contact insecticides with wide effect on a whole range of noxious insects (e. g.Lepidoptera, Coleoptera, Hemiptera, etc.).It is very effective in small amounts, for example, preparation Ripkord in the dose of 0.1-0.21.ha-1 (Sedokur 1986), 25-75 g. ha-1 (Piskac et a1.1985).Resistance of insects to this preparation is small and its action affects various developmental stages (eggs, larvae, adult insects).It is easily applied (sprays, emulsions, powders).Acute oral LD.o in rats is most trequently specified within the range 200-300 mg.kg-1 (Sapiets et a1.1984;Sedokur 1986; Mefnikov et a1.1980), in mice 63-805 mg .kg-I, in chicken 200 mg .kg-1 (Sapiets et a1.1984; Marhold et a1.1986).It is used not only against noxious insect species (flies, horseflies, cockroaches, mosquitos) but also as an ectoparasitic preparation (e.g.scab).