COMPLEMENT-FIXATION TEST IN HEPATIC COCCIDIOSIS OF RABBITS

Abstract

Antibodies to Eimeria stiedae were measured in rabbit serum by complement fixation. The titre rose to a maximum at about the 22nd day after infection, remained at this level for about 20 days and then declined. Antibodies were still detectable up to 160 days after infection. Evidence of past or present slight E. stiedae infection was found in clinically normal rabbits whose sera fixed complement with E. stiedae antigens. Challenge of rabbits which had recovered from a near-fatal infection had no effect upon the complement fixation titres of their sera. The serum of a rabbit which had been injected with alum-precipitated antigen fixed complement with E. stiedae antigens. However, the animal was still susceptible to a superimposed oral infection which had the effect of further increasing the serum titre.