Abstract
Extract Preliminary investigations carried out by Jacobs (1961) Jacobs, Leon . 1961. U.Z. vet. J., 9: 85–85. [Taylor & Francis Online] [Google Scholar] in New Zealand suggested that sheep with naturally acquired Toxoplasma dye test antibody, were protected from artificial infection with the proliferative and cystic forms of Toxoplasma. The following investigation is an extension of Jacobs's observations, using larger numbers of animals.