Immunological Studies on Experimental Infection of Pigs withAscaris suumGoeze, 1782 I. An Introduction with a Review of the Literature and the Demonstration of Complement-fixing Antibodies in the Serum

An introduction to a study of immunity againstA. suumin the pig is given. A review of the literature on the life cycle, a note on terminology and a general discussion on immunity to helminths has also been included. 2. By first removing the procomplementary activity of pig serum to guineapig complement with hydrochloric acid, it was possible to apply the complement fixation test to a study of the antibody response to experimental infection withA. suum. 3. Using an alcoholic extract of uterus, oviducts and ovaries of the adult femaleAscarisworm as antigen, antibodies against this nematode were first detected in two experimentally infected pigs ten days after infection. A peak of antibody concentration from the thirteenth to the seventeenth day of infection was followed by a decline in the antibody content of the serum to the forty-first day; after which no antibody was detected.