Jansen, B.C.Jansen, B.C.2016-07-062016-07-0620161967Jansen, BC 1967, 'The duration of immunity to pulpy kidney disease of sheep’, Onderstepoort Journal of Veterinary Research, vol. 34, no. 2, pp. 333-343.0330-2465http://hdl.handle.net/2263/53875The journals have been scanned in colour with a HP 5590 scanner; 600 dpi. Adobe Acrobat v.11 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.It was shown that the immunity induced by a primary and secondary dose of antigen varying from 25 to 135 Lf APT, protected sheep for only about nine weeks. Any booster dose given before a year after the primary injection resulted in protective titres lasting for periods up to about 20 weeks. When a sound basic immunity is established, e.g. with two doses of 135 Lf, sheep are protected to the same extent by a large (135 Lf) or small (25 Lf) booster dose given one year after the primary injection. The protection thus effected lasts for at least one year. When sheep with a sound basic immunity receive a booster of 135 Lf after one year and a second booster of 135 Lf after a further year, they are protected against pulpy kidney disease for at least three years following the last injection. A single injection of epsilon toxoid in Freund's complete or incomplete adjuvant protects sheep for at least two years.en© 1967 ARC - Onderstepoort and Faculty of Veterinary Science, University of Pretoria (original). © 2016 University of Pretoria. Dept. of Library Services (digital).Veterinary medicineVeterinary medicine -- South AfricaSheep -- InfectionsType D enterotoxemia of sheepArticle