Erysipelas in egg-laying chickens serological investigation.

Examination was made of 81 strains of Erysipelothrix rhusiopathiae isolated from chickens which had died of septicaemic erysipelas. The strains originated from two flocks producing eggs for consumption, 34 from Flock A and 47 from Flock B. Typing was performed by the tube precipitation and the agar gel precipitation test. All strains from Flock B belonged to type 1b, while 27 strains from Flock A belonged to type 4. The seven strains which could not be classified require further examination including production of antiserum for each strain in order to obtain, if possible, sera with precipitating antibodies.