DISEASES OF POULTRY. 



105 



time, or whether the warm season favors the dissemi 

 nation and the development of the disease is not clear 

 That infection may occur in older 

 birds and in cold weather is de- 

 monstrated by Moore's experi- 

 ments in which turkeys five 

 months old and weighing six 

 to eight pounds were exposed 

 in November and December, and 

 in which the disease was well de- 

 veloped by the latter part of De- 

 cember and the early part of 

 January. 



The disease begins in the caeca ; 

 sometimes it is found in but one 

 of these organs but oftener it af- 

 fects both. With the progress of 

 the disease, the mucous mem- 

 brane may be shed and a coagu- 

 lable fluid poured out into the 

 caecum. In some cases this ex- 

 udate appears as isolated masses, 

 which adhere to certain spots of 

 the mucous membrane ; in others, 

 it fills the entire tube with a yel- 

 lowisb-white mass or plug, built 

 up of concentric layers and con- 

 sisting of a mixture of blood 

 corpuscles, fibrin and round cells. 

 The wall of the afiected caecum is thickened, and the 

 inflammation may extend to the outer or serous coat 

 upon which yellowish exudates are sometimes seen that 

 may bind the organ to the other caecum, to other parts 

 of the intestine or to the abdominal wall. In no case 



Fig". 18. — Caeca of diseas- 

 ed turkey. 



