Schistosoma mattheei in the ox: the serological response.

Thirty Friesian steers were infected with Schistosoma mattheei and the antibody response was followed for up to 76 weeks by the complement fixation (CF), indirect haemagglutination (IH) and indirect immunofluorescent (IF) tests. CF and IF antibodies rose to a peak at about 25 weeks and then fell, while IH antibodies rose more slowly and remained high. Peak IH and IF titres were proportional to the level of infection. Peak CF titres were reduced in animals on a low plane of nutrition. There was a strong cross-reaction to Fasciola gigantica and Paramphistomum microbothrium in the CF test while the IH and IF tests were specific. The IF test proved of value in the diagnosis of naturally occurring clinical schistosomiasis.