Failure to stimulate a local immune response in the mammary gland of the sow using intraperitoneal "priming".

An experiment was carried out to determine whether a local immune response could be produced in the mammary gland of sows by "priming" the animals with an intraperitoneal injection of antigen without adjuvant. Adjuvant was not used in the immunization regimen because it had been shown to induce acute peritonitis and multiple abscess formation when injected intraperitoneally in pigs. Four pregnant sows were "primed" by intraperitoneal injection of ferritin; a second dose of the antigen was given two weeks later into the lumen of the jejunum. Another group of pregnant sows was given two intra-muscular injections of ferritin two weeks apart and a third group of sows served as non-immunized controls. Antibody titres and concentrations of IgG, IgA and IgM in colostral and milk whey suggested that a local immune response had not been stimulated in the mammary glands of these sows. Mammary tissue was examined for the presence of immunoglobulin-containing and specific antibody-containing plasma cells. Results of these studies confirmed that intraperitoneal/intrajejunal injection of ferritin without adjuvant was not successful in inducing a local immune response in the mammary gland.