Oesophagostomum radiatum: the effect of different adjuvants on vaccination with a partially purified protective antigen.

The components of a soluble extract of adult Oesophagostomum radiatum were separated into four fractions by gel filtration chromatography on a Superose-12 column. The second fraction had a molecular weight range of approximately 60,000-65,000 as judged by SDS gel electrophoresis. Vaccination of calves with this fraction significantly (P < 0.05) reduced faecal egg output after challenge infection. In addition, the packed cell volume of vaccinated calves was higher than that of control calves (P < 0.05). The effect of three adjuvants on the vaccine activity was compared. Fraction 2 presented in dextran sulfate reduced the faecal egg count by 93.6% (P < 0.05), Fraction 2 in Freund's complete adjuvant reduced the faecal egg count by 27% (P = N.S.). Quil A was ineffective as an adjuvant.