RECIPROCAL TRANSMISSION TESTS WITH INFECTIOUS CATARRH OF CHICKENS, MICE, AND RATS.

Infectious catarrh of chickens (fowl coryza of slow onset) was not transmissible to mice or rats by nasal instillation of the specific coccobacilliform bodies. Exudates were also inactive in both rodents on foot pad injection. The infectious catarrhs of the mouse and the rat were reciprocally transmissible by the nasal injection of exudates or tissue cultures of the respective coccobacilliform bodies and by direct contact. Exudates and cultures also produced an arthritic reaction in both hosts on foot pad injection. The coccobacilliform bodies of mouse catarrh were innocuous in chickens on nasal instillation, whereas those of rat catarrh were established locally but were maintained for only two passages. In the opposite host each of the two rodent forms of infectious catarrh reproduced the typical features of the naturally acquired disease, a highly fatal pneumonia being characteristic of the mouse but not of the rat.