STUDIES ON RESPONSE OF EWES TO LIVE CHLAMYDIAE ADAPTED TO CHICKEN EMBRYOS OR TISSUE-CULTURE

  • 1 January 1976
    • journal article
    • research article
    • Vol. 40  (1) , 46-52
Abstract
Ewes infected before gestation with chicken embryo or tissue culture adapted chlamydial strain B-577 were challenge inoculated with the homologous strain at 4-18 wk of gestation. The ewes responded with group specific complement fixing antibody titers of 1:8-1:256 by the 2nd wk after initial infection. A secondary antibody response in the surviving challenge inoculated ewes occurred at the time of lambing and reached titers of 1:32-1:256 by the 2nd wk after parturition. Group specific complement fixing antibodies did not appear to play a significant role in resistance to chlamydial infection. Ewes infected with the chicken embryo adapted strain B-577 excreted chlamydiae in their feces 60 days after inoculation. Chlamydiae were not recovered from feces of ewes infected with the tissue culture adapted strain B-577. Placentas of ewes i.v. challenge inoculated were consistently infected. Chlamydiae were recovered from placentas, some fetuses and lambs. In 2 instances when challenge inoculation was given i.m., infection was detected only by the direct fluorescent antibody method.