MASS. EXPERIMENT STATION BULLETIN No. 284 



Photograph 2. — Bird No. I — Non-infected Hen; Bird No. II — Infected Hen. 

 Pulloruni diseased birds as a rule cannot be differentiated from the non-infected by 

 physical examination. Apparently normal, well-developed birds may be affected with 

 the disease. Infection in such birds can be detected either by the agglutination test or 

 by bacteriological examination. Refer to questions 4 and 33. 



Photograph 3 — Ovaries Removed from Hens. 

 Specimens I and HI, showing irregular shaped, discolored and pedunculated ova, 

 are affected with pullorum disease. Specimen II, showing normal ova, is not affected. 

 Refer to question 4. 



