Passive Immunity to Ascaris Suum: Colostral Transfer from Sows to Their Piglets

The purpose of this study was to determine whether pregnant sows could be actively immunized against A. suum through repeated oral doses of ascarid eggs, or if at a maturity swine have been naturally immunized through repeated exposure to eggs. A comparison was made between passive immunity to A. suum acquired by: piglets suckling naturally (farm) infected and experimentally immunized against A. suum; piglets suckling a sow naturally (farm) infected; and piglets which were hysterectomy-derived and colostrum-deprived. Cellulose acetate electrophoresis was applied to sera of sows to determine changes in gamma globulin concentrations.These samples were taken at weekly intervals during immunization.Cellulose acetate electro-phoresis was also applied to colostral and milk wheys to determine if there was a difference between immunized sows and the nonimmunized sow. Piglets serum patterns were determined to compare differences in per cent gamma globulin and gamma concentrations. Immunodiffusion and immunoelectrophoresis were applied to whey globulins using various saline extracts of adult worms and larval stages as antigens.Crude, semipurified and purified enzymes from both adult and larval stages of A. suum were tested for inhibition by antibodies in serum, colostral and milk wheysof two immunized sows and one nonimmunized sow. Three sows of the Yorkshire breed were used in this study.These animals were raised under farm conditions where piglets were kept with their dams until five weeks of age. At weaning, piglets were put into pens and fed ad libitum until weighing approximately 200 pounds. Sows were limit fed during breeding and gestation.Exposure to A. suum was highly probable under such conditions.Therefore, fecal flotation for identification of worm eggs was prepared for each sow at the time of isolation at these facilities. Several conclusions were made from this study among them was that results of challenging piglets with infective larvae of A. suum and enzyme inhibition analyses of this study suggest that all sows had specific antibodies to A. suum in colostrum and milk. Advisor: Donald L. Ferguso