What question did this study set out to answer?

To evaluate whether vaccination of ewes with an incomplete strain (S48) of Toxoplasma gondii confers protective immunity against oral parasite challenge during pregnancy.

August 3, 1991Veterinary Record

Vaccination of sheep with a live incomplete strain (S48) of Toxoplasma gondii and their immunity to challenge when pregnant

View Full Paper

Ask AI

Bookmark

Authors

DBD. Buxton KTK.M. Thomson SMS. Maley

Discussion

Member takes

Overview

Controlled trial demonstrates improved fetal viability following S48 Toxoplasma gondii vaccination in pregnant sheep, indicating protective efficacy against congenital toxoplasmosis.

Key Points

To evaluate whether vaccination of ewes with an incomplete strain (S48) of Toxoplasma gondii confers protective immunity against oral parasite challenge during pregnancy.
Sixty-four ewes were vaccinated before mating with S48 tachyzoites cultured either in mouse peritoneal cavities (group 1) or Vero cells (group 2), while 30 ewes remained unvaccinated (group 3).
All ewes were mated 77 days post-vaccination and orally challenged with 2000 sporulated T gondii oocysts at 89 to 90 days of gestation, alongside 20 unchallenged vaccinated and unvaccinated controls.
Fetal and lamb viability was 17.8% (8/45) in unvaccinated challenged ewes, compared with 72.3% in mouse-derived and 80.8% in Vero cell-derived vaccine groups.
Vaccinated challenged ewes had shorter, less severe fevers, more rapid antibody titre elevations, and higher single lamb birthweights than unvaccinated challenged ewes.
Precolostral serum analysis indicated that nearly two-thirds of lambs born to vaccinated ewes were infected in utero despite remaining clinically viable.

Cite This Study

Buxton et al. (1991) studied this question.

synapsesocial.com/papers/69da7cd98988aeabbe686d49 https://doi.org/10.1136/vr.129.5.89

View Full Paper

Ask AI

Bookmark

August 3, 1991Veterinary Record

Vaccination of sheep with a live incomplete strain (S48) of Toxoplasma gondii and their immunity to challenge when pregnant

View Full Paper

Ask AI

Bookmark

Authors

DBD. Buxton KTK.M. Thomson SMS. Maley

Discussion

Member takes

Overview

Controlled trial demonstrates improved fetal viability following S48 Toxoplasma gondii vaccination in pregnant sheep, indicating protective efficacy against congenital toxoplasmosis.

Key Points

To evaluate whether vaccination of ewes with an incomplete strain (S48) of Toxoplasma gondii confers protective immunity against oral parasite challenge during pregnancy.
Sixty-four ewes were vaccinated before mating with S48 tachyzoites cultured either in mouse peritoneal cavities (group 1) or Vero cells (group 2), while 30 ewes remained unvaccinated (group 3).
All ewes were mated 77 days post-vaccination and orally challenged with 2000 sporulated T gondii oocysts at 89 to 90 days of gestation, alongside 20 unchallenged vaccinated and unvaccinated controls.
Fetal and lamb viability was 17.8% (8/45) in unvaccinated challenged ewes, compared with 72.3% in mouse-derived and 80.8% in Vero cell-derived vaccine groups.
Vaccinated challenged ewes had shorter, less severe fevers, more rapid antibody titre elevations, and higher single lamb birthweights than unvaccinated challenged ewes.
Precolostral serum analysis indicated that nearly two-thirds of lambs born to vaccinated ewes were infected in utero despite remaining clinically viable.

Cite This Study

Buxton et al. (1991) studied this question.

synapsesocial.com/papers/69da7cd98988aeabbe686d49 https://doi.org/10.1136/vr.129.5.89

Also Consider

Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context:

View Full Paper

Ask AI

Bookmark