Antibody response in the bovine genital tract to intrauterine infusion of Actinomyces pyogenes

Antibody titres and immunoglobulin concentrations were measured in serum and in uterine and vaginal secretions from five heifers after intrauterine infusion of Actinomyces pyogenes. Infection stimulated an increase in uterine antibody titres of IgG2 and IgA, which approached significance. There was no increase in antibody titres in vaginal secretions or in serum. For each class of immunoglobulin, the ratio of specific antibody to immunoglobulin tended to increase in uterine secretions after infection, whereas no change was detected in the serum. These results indicate that at least a portion of the antibody was derived from local uterine synthesis.