抄録
Many valuable reports on strangles have already been published, but studies on the complement fixation are very scarce. In 1922, Broco-Russeu, Forgeot, and Urbain reported that they obtained positive results in the complement fixation test with a serum produced from horses immunized against streptococcus equi and an antigen obtained from it, while the test with an antigen from other kinds of streptococcus gave always negative results.
Having been engaged since 1921 in the determination of an antibody which is thought to be present in an immune serum against strangles, the writer has come to the following conclusions:
1. A serum produced from rabbits hyperimmunized against streptococcus equi gives always positive results in the complement fixation test, and the diversity of antigens, whether made from the corresponding streptococcus equi or from other strains of it, exerts little influence upon this reaction.
2. The immune rabbit's serum against streptococcus equi gives positive results in the complement fixation test in which is employed an antigen from the hemolytic streptococci isolated from cows, swine, goats, and dogs; the results, however, are negative, if a non-hemolytic streptococcus be used as antigen (one case in exception).
3. The serum from horses highly immunized against streptococcus equi has the same property as that from immune rabbits.
4. The serum from horses attacked by strangles gives either positive or negative results, but the serum from horses which have some metastatic abcesses in the abdominal cavity, gives always positive results.
