KINETICS OF DETECTION OF BLASTOGENIC RESPONSES OF NEONATAL CALVES INOCULATED IN UTERO WITH TETANUS TOXOID, KILLED MYCOBACTERIUM-BOVIS, AND KILLED BRUCELLA-ABORTUS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 40  (4) , 576-579
Abstract
Pregnant cows (9) were laparotomized and their fetuses were immunized with tetanus toxoid, killed B. abortus, and killed M. bovis. Blastogenesis assays and total leukocyte and differential counts were done when the calves were 1, 2, 3, 7, 14, 21, 28 and 60 days of age. Initial blastogenesis responses to antigens [Ag], phytohemagglutinin and concanavalin A were not positive as frequently as the responses obtained when the calves were 2-3 wk of age. The probability of obtaining a positive response to an Ag was positively correlated with the magnitude of the response, as determined by delayed-type hypersensitivity skin reactions. Leukocyte and differential WBC [white blood cell] counts in immunized calves were similar to those of unimmunized calves. The mean leukocyte count for the immunized calves remained near 16,000 cells/mm3; blood obtained in the 1st few days after birth contained a greater number of neutrophils than lymphocytes, whereas lymphocyte-to-neutrophil ratio gradually approached those of adult cattle, in which lymphocytes predominate.