considered suspicious of harboring the disease. In all but one instance the flocks 

 consisted of mature chickens. The single chick case was a broiler flock which 



ii originated from an out-of-state hatchery. 



In eight of the twelve adult flocks acute outbreaks of pullorum disease, ac- 

 companied with a high morbidity rate, a significant mortality, and a decline in egg 

 prochiction were observed. In two adult flocks the infection was detected in ex- 

 hibition birds when tested at the Boston Poultry Show. The remaining two adult 

 flocks had a suspicious history of pullorum disease but did not reveal evidence of 



J infection when tested with the agglutination method. 



Table 7. 



Pullorum Disease Eradication Results In Thirteen Nonbreeding 

 Chicken Flocks 



FLOCK NO. METHODS OF ERADICATION 



1 Periodic testing and partial depopulation. 



2 Partial depopulation. 



3 Testing followed by total depopulation. 



4 Periodic testing and partial depopulation. 



5 Partial depopulation followed by testing. 



6 Total depopulation. 



7 Testing and partial depopulation. 



8 Total depopulation. 



9 Complete flock test. 



10 Partial depopulation followed by testing. 



11 Total depopulation after 10 weeks of age. 



12 Partial test with no reactors. 



13 Total flock tested with no reactors. 



Flocks 1 to 8: Mature birds which experienced acute outbreaks identified by 

 isolation of S. pullorum. 



Flocks 9 and 10: Mature birds with chronic pullorum disease identified with 

 the tube agglutination test. 



Flock 11: A chick flock which experienced an acute outbreak identified by isola- 

 tion of S. pullorum. 



Flocks 12 and 13: Mature birds which had a suspicious history of pullorum 

 disease. 



Table 7 gives a brief summary of the findings in the thirteen flocks and the 

 manner in which the infection was eliminated. In eight flocks the tube agglutina- 

 tion test was used as a means to establish a clean flock. A total of 49,167 samples 

 was tested from some of these flocks. The cooperation received from the flock 

 owners has been most gratifving in our efforts to eliminate the known foci of in- 



11 



