Effects of Pesticides on Immune Competency: Influence Of Methyl Parathion and Carbofuran on Immunologic Responses to Salmonella Typhimurium Infection
Date of Award:
Doctor of Philosophy (PhD)
Animal, Dairy, and Veterinary Sciences
Joseph C. Street
Joseph C. Street
Paul B. Carter
R. P. Sharma
J. LeGrande Shupe
Immunologic competence is correlated with resistance to infectious disease which may be affected by exposure to certain compounds. Methyl parathion (MP) and carbofuran (CF) have been reported to affect the development of active immunity in the rabbit and the present research was conducted to quantify the dosage relationships of these two pesticides to both host resistance and acquired resistance in the mouse.
Preliminary study was made on the virulence of Salmonella typhimurium in mice. Mortality rates among infected animals fed Purina Laboratory Chow diet providing 0.08, 0.7 3.0 mg MP/kg/day or 0.1, 0.6, 1.0 mg CF/kg/day along with untreated controls were determined and protection afforded the animals by vaccination under the influence of chemical treatment was examined. The nature of dose response was further investigated with the study of various parameters of host defense against microbial infection. Measurements were made of the bacterial population in tissues of mice during and after the course of infection, differential leukocyte counts, in vivo and in vitro opsonic effect of serum, clearance of the reticulo-endothelial system, agglutination titers of serum, total serum gamma-globulin levels, serum immunoglobulin levels with classes and subclasses, and lymphocyte response to mitogen stimulation.
Dosage-related increases in mortality were seen in unvaccinated mice under both chemical treatments, and protection by immunization was decreased. Pesticide treatment extending beyond two weeks was required to obtain significant increases in mortality. Increased mortality was associated with increased numbers of viable bacteria in blood, decreased total gamma-globulins and specific immunoglobulins in serum, and reduced splenic blast transformation in response to mitogens. Serum opsonic activity of CF-treated animals was slightly reduced. These results support those of other investigations indicating effects of environmental toxicants upon the resistance and immune competency of experimental animals.
Fan, Anna M., "Effects of Pesticides on Immune Competency: Influence Of Methyl Parathion and Carbofuran on Immunologic Responses to Salmonella Typhimurium Infection" (1980). All Graduate Theses and Dissertations. 4220.
Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .