Studies on the Salmonellosis of Fowls with Special Reference to Diagnosis of S. Pullorum Carrier

I. Studies on the fluctuation of agglutination titer in S. pullorum carrier

Abstract

Serological studies, particulary the agglutination test were carried out on 11 naturally infected hens with S. pullorum. The results were summarized as follows.
1. Agglutinin titer of the sera obtained from these S. pullorum carriers were rather erratic, 2 (18%) out of the 11 hens being consistently positive, 4 (36%) of them undulatory positive and the remaining 5 (45%) intermittently positive (intermittent type).
2. From the point of view of the carrier diagnosis, this “intermittent type” of reaction seemed to be most important, demonstrating alternatively positive and negative reaction on the agglutination test, within the extent of approximately 1: 50 to 1: 200.
3. On the other hand, hens of this type generally showed negative reaction on the rapid plate-agglutination test with the whole blood. Occasionally, however, did they de monstrate weakly positive reaction.
4. Healthy hens belonging to the “intermittent type” may play the most important role in the epidemic of this disease.