IMMUNOLOGICAL EFFECT OF DERMONECROTIC TOX IN OF BORDETELLA-BRONCHISEPTICA AND PASTEURELLA-MULTOCIDA ON SPF PIGLETS

SPF piglets aged twelve weeks received ten parenteral applications eac h of 15 mug DNT of Bordetella bronchiseptica over a period of five wee ks. This treatment, apart from minor atrophy of the conchae, led to at rophy of the spleen as well as to decline of T-cells in spleen, lymph nodes and peripheral blood. Ten comparable applications of 15 mug DNT of Pasteurella multocida resulted in minor histological alterations to lymphatic organs as well as in minimum numerical decline of lymphocyt es. The amount of neutralising antibodies in blood serum and nasal muc us of piglets immunized twice with toxoids was higher than that record able from DNT-treated piglets.