Complement Fixation and Agglutination Tests for Salmonella Pullorum Infection

Abstract

For several years we have been testing domestic fowl for bacillary white diarrhea without being able to decide on the exact standard to indicate actually dangerous infection of the carriers. There are many low reacting birds which have recovered from the disease and are immune. The serum from others may give nonspecific reactions because of certain intercurrent infections not of a dangerous character, while still others whose serum reacts with the Salmonella pullorum antigen only in low dilutions are known to be actual carriers of the bacillary white diarrhea organisms and to eliminate them through the egg. Some of these eggs hatch and cause heavy losses of chicks from normal hens. In an attempt to determine which birds are carriers and of danger to the remainder of the flock extensive experiments were conducted during the past year in comparing, among others, the agglutination and the complement fixation tests of serums from a flock at this station. We have found few comparative tests of this type and in those mentioned in the literature it has been difficult to make a direct comparison of the two tests on the same dilution of the serum.