Документ взят из кэша поисковой машины. Адрес оригинального документа : http://kodomo.cmm.msu.ru/~xenia_l/article.doc Дата изменения: Mon Oct 20 01:31:56 2008 Дата индексирования: Tue Oct 2 00:23:42 2012 Кодировка:

Ovine Enzootic Abortion (OEA): a comparison of antibody responses in
vaccinated and naturally-infected swiss sheep over a two year period

Background
Prevention and control of ovine enzootic abortion (OEA) can be achieved by
application of a live vaccine. In this study, five sheep flocks with
different vaccination and infection status were serologically tested using
a competitive enzyme-linked immunosorbent assay (cELISA) specific for
Chlamydophila (Cp.) abortus over a two-year time period.
Results
Sheep in Flock A with recent OEA history had high antibody values after
vaccination similar to Flock C with natural Cp. abortus infections. In
contrast, OEA serology negative sheep (Flock E) showed individual animal-
specific immunoreactions after vaccination. Antibody levels of vaccinated
ewes in Flock B ranged from negative to positive two and three years after
vaccination, respectively. Positive antibody values in the negative control
Flock D (without OEA or vaccination) are probably due to asymptomatic
intestinal infections with Cp. abortus. Excretion of the attenuated strain
of Cp. abortus used in the live vaccine through the eye was not observed in
vaccinated animals of Flock E.
Conclusion
The findings of our study indicate that, using serology, no distinction can
be made between vaccinated and naturally infected sheep. As a result,
confirmation of a negative OEA status in vaccinated animals by serology
cannot be determined.