PERIPARTURIENT REDUCTION IN BUFFALO OF MITOGEN-INDUCED LYMPHOCYTE-PROLIFERATION AND ANTIBODY TO TOXOCARA-VITULORUM

Lymphocyte and antibody reactivity were examined during the peripartur ient period in buffalo cows naturally infected with Toxocara vitulorum . Titres of antibodies to an extract of T. vitulorum larvae increased about 3 months before parturition. Antibody titres declined at about t he time of parturition and remained low for up to 3 months into lactat ion. Lowered titres were found in the IgG class and not the IgM class of immunoglobulins. Levels of lymphocyte transformation induced by the mitogens concanavalin A and pokeweed mitogen declined markedly from o ne to 2 weeks before until one to 2 weeks after parturition. The relat ionship between this suppressed immunological reactivity and vertical transmission of T. vitulorum larvae is discussed.