ELEVENTH ANNUAL REPORT ON ERADICATION OF 



PULLORUM DISEASE IN MASSACHUSETTS 



1930-31 



By H. Van Roekel' 



Introduction 



The contents of this bulletm inchide a discussion of piillonim disease, the 

 objective in its eradication, and the progress made in testing during the past 

 few years with special reference to the past season. The purpose of the 

 discussion is to make poultrymen more familiar with tlie cause and nature 

 of the disease, and thus enable them to cooperate more intelligently and ef- 

 ficiently in the eradication program. A report on the progress in testing 

 points out that the disease is being eradicated from breeding flocks in this 

 State. 



Nature of the Disease 



Pullorum infection, caused by a specific microorganism (Salmonella pullor- 

 um), manifests itself as an acute disease in chicks and occasionally in adults. 

 In the adult, however, the infection is usually localized in one or more organs 

 and produces little or no systemic effect in the majority of cases. 



In chicks, the disease may manifest itself within a few days after hatching. 

 The onset and severity of the symptoms depend upon the amoimt of infection 

 in the body, the ability of the organism to produce the disease, the resistance 

 of the chick, and the care given by the poultrymen. In some cases of dis- 

 eased chicks, little or no evidence which might suggest infection is observed, 

 whereas in other cases, all the possible manifestations of the disease are 

 foimd. The following symptoms may be revealed: depressed vigor; loss of 

 appetite; remaining under the hover; frequent cheeping; droopy wings; 

 shortened bodies; the adherence of white chalky excreta to the down around 

 the vent; marked depression and exhaustion, followed by death. None of 

 these symptoms are characteristic or specific of pullorum disease alone, since 

 they may be encountered in other health disturbances of chicks. The mortal- 

 ity rate may vary from slight to heavy, or even 100 per cent. Losses may be 

 observed within two or three days after hatching and may continue until the 

 chicks are three weeks of age or older. The heaviest losses usualljr occur dur- 

 ing the second week of chickhood. 



Diagnosis of the disease in young chicks should be based upon bacterio- 

 logical examination. Chicks which succumb to the disease do not always show 

 gross changes in organs such as the liver, heart, and lungs. Some workers 

 have entertained the opinion that a yellow or ochre-colored liver and an un- 



^ Assisted by K. L. Bullis, O. S. Flint, and Miriam K. Clarke. 



Credit is due to Dr. Glen L. Dunlap for the necropsy results reported in this bul- 

 letin ; and consideration is extended to Dr. John B. Lentz, Head of the Department of 

 Veterinary Science, for administrative assistance. Appreciation is extended to various 

 agencies which cooperated in this work, with special reference to County Extension 

 Service. 



