Toxoplasmosis in sheep III. Further evaluation of the ability of a live Toxoplasma gondii vaccine to prevent lamb losses and reduce congenital infection following experimental oral challenge

Authors: Te Punga WA, O'Connell E, Wilkins MF
Publication: New Zealand Veterinary Journal, Volume 36, Issue 2, pp 86-89, Jun 1988
Publisher: Taylor and Francis

Animal type: Livestock, Production animal, Ruminant, Sheep
Subject Terms: Abortion/stillbirth, Animal remedies/veterinary medicines, Biosecurity, Disease control/eradication, Epidemiology, Reproduction, Immune system/immunology, Protozoa, Reproduction - female, Disease/defect, Research/development, Zoonosis, Infectious disease, Vaccination, Public health
Article class: Scientific Article

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Abstract: The aim of this study was to compare the ability of a live incomplete strain (Strain 48) and a live complete strain (Strain 89) of Toxoplasma gondii to protect against abortion and congenital infection follalwing an oral challenge of T. gondii oocysts. Sixty-nine two-tooth ewes were immunised pre-tupping with live Strain 48 of T. gondii tachyzoites and seventy ewes were immunised with Strain 89. Eighty-two serologically negative ewes served as controls. At mid-pregnancy half of the ewes were challenged orally with T. gondii oocysts (2x10⁵/ewe). The ewes vaccinated with Strain 48 were significantly (p<0.05) protected against the effects of experimental challenge and the rate of congenital infection was also significantly (p<0.15) reduced. The ewes vaccinated with Strain 89 were also significantly (p<0.05) protected. The serological response to challenge as measured by both the Dye test and the Indirect Haemagglutination test varied considerably between the two vaccinated groups.

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