Abstract
Extract
The complement fixation (CF) test has been used for the diagnosis of Brucella ovis infection in sheep by several workers (CitationClapp, 1955, Citation1961; CitationBiberstein and McGowan, 1958; CitationBiberstein et al, 1964; CitationRyan, 1964; CitationGorrie, 1964, Citation1968; CitationHughes and Claxton, 1968). When the CF test described by CitationClapp (1961) was used in a study of natural and experimental infections in rams (CitationRis, 1964), it was found that some rams excreting Br. ovis organisms in their semen had no detectable CF titres. This occurred some 6 months after initial infection when the rams had been serologically positive for at least 2 months. However, CF antibodies were again detected after an interval which varied from 2 weeks to 3 months.