IMMUNE-RESPONSE OF CALVES GIVEN MYCOPLASMA BOVIS ANTIGENS

  • 1 January 1977
    • journal article
    • research article
    • Vol. 41  (3) , 279-286
Abstract
Seven calves 7-30 days of age were given Mycoplasma bovis antigen by different routes. Immunization was in 2 phases. The 1st consisted of single or multiple s.c., i.v. or oral doses of antigen for 2-4 wk. The 2nd phase consisted of multiple s.c. or i.d. [intradermal] injections given from the 8th to the 19th wk. The experiment was terminated at 26 wk. Antibody titers were followed by indirect hemagglutination, growth inhibition and tetrazolium reduction inhibition. Total serum protein, protein fractions and Ig[immunoglobulin]G and IgM concentrations were determined in serum from 1 calf, and the distribution of indirect hemagglutination antibodies in IgG and IgM classes were determined in sera from 2 of the calves. Indirect hemagglutination titers of 1280 and peak titers of > 20,480 occurred after the 1st and 2nd phases, respectively. There was no relationship between total serum IgG or IgM concentrations and indirect hemagglutination titers. In 1 calf given M. bovis antigen in 1 dose s.c. and 5 weekly doses i.v. in phase I, indirect hemagglutination antibodies appeared in IgM within 1 wk, and IgG by 4 wk. IgG antibody activity rose steadily until the 17th wk but declined at the 26th wk, whereas IgM activity after the initial rise dropped at the 13th wk but rose even higher as a result of 2nd phase i.d. injections. Another calf given 6 weekly i.v. doses of M. bovis antigen in phase I developed indirect hemagglutination antibodies in IgM, peaking at 4 wk then declining, but with no IgG response. Activity in IgM and IgG occurred after the 2nd phase. Growth inhibition antibodies were found only on 2 occasions in serum from 1 calf and tetrazolium reduction inhibition activity when tested never gave titers exceeding 1:32.