IMMUNE-RESPONSE OF PREGNANT COWS TO BOVINE ROTAVIRUS IMMUNIZATION

  • 1 January 1984
    • journal article
    • research article
    • Vol. 45  (1) , 49-58
Abstract
Fifteen pregnant Holstein cows were freely assigned to 3 experimental groups (5 cows in each group). Cows in group I were inoculated i.m. and intramammarily (IMm) with Ohio Agricultural Research and Development Center (OARDC) tissue culture-propagated modified-live Nebraska calf diarrhea bovine rotavirus with added adjuvant (OARDC vaccine-immunized cows). Group II cows were given i.m. injections of a commercial modified-live rotavirus-coronavirus vaccine (commercial vaccine-immunized cows) and the remaining 5 cows were noninoculated controls (group III). Rotavirus antibody in colostrum and milk was mainly associated with IgG1, and less so with IgG2, IgA and IgM, as analyzed by the enzyme-linked immunosorbent assay (ELISA), using monospecific anti-bovine IgG1, IgG2, IgM and IgA sera. In serum, the rotavirus antibody was distributed almost equally between IgG1 and IgG2. The same relationships appeared in both immunized and nonvaccinated cows. All OARDC vaccine-injected cows had virus-neutralization (VN) and ELISA IgG1 rotavirus antibody titers in serum and mammary secretions at significantly increased levels (at least 100-fold; P < 0.05) compared with the titers in groups II (commercial vaccine-immunized cows) and III (controls). Serum, colostrum and milk antibody titers from these latter 2 groups did not differ statistically. The ELISA IgG2, IgA, and IgM rotavirus antibody titers also were significantly greater in mammary secretions from OARDC vaccine-immunized cows than in groups II and III cows. There was a high correlation between ELISA IgG1 and VN rotavirus antibody titers for all samples tested (r = 0.97, P < 0.001), but ELISA IgG1 antibody titers were consistently higher than VN titers. The ELISA IgG1 and VN antibody titers of milk samples collected from cows 30 days after parturition were higher from the OARDC vaccine-immunized cows (ELISA IgG1, geometric mean titer (GMT) = 3511; VN GMT = 1689) than were titers from the group II cows (ELISA IgG1 GMT = 39; VN GMT = 33) or group III cows (ELISA IgG1 GMT = 21; VN GMT = 19). These results indicate that i.m. plus IMm immunization of pregnant cows, using modified-live bovine rotavirus with added adjuvant, may significantly enhance serum, colostrum and milk rotavirus antibody titers; i.m. vaccinal inoculation of pregnant cows with a commercial modified-live rotavirus-coronavirus vaccine may not.