26o 



INFECTIOUS ENTERO-HEPATITIS 



Yellowish exudates are sometimes found outside of the diseased 

 caecum on its serous covering and they bind it inextricabh' to- 

 the other caecum or to the intestine or attach it to the abdomi- 

 nal wall. In these stages, the microparasite is not found. It 

 seems to have done its work b}' destro^'ing the mucous mem- 

 brane and to have left the field for miscellaneous bacteria. 



Other portions 

 of the digestive 

 tract are not affect- 

 ed. The secondary 

 lesions are found in 

 the liver although 

 in some cases they 

 do not appear. The 

 organ itself is en- 

 larged to probably 

 twice the normal 

 size. Over the sur- 

 face are distributed 

 roundish, d i s c o 1- 

 ored spots, d i s- 

 tinctl}' demarcated 

 from the surround- 

 ing tissue. These may be distributed uniformly over the whole 

 surface of the liver or they may be limited in number to a few. 

 They vary from 3 to 15 mm. in diameter. Several types of 

 these spots appear corresponding to different conditions of the 

 diseased tissue. We have in the earh-, most active disease 

 process sharply defined circular areas of a lemon yellow, of a 

 neutral gray or of an ochre yellow color. The spot is not homo- 

 geneous in structure, but made up of a delicate network of 

 grayish yellow, dead tissue. 



In another class of spots there is a mottled brownish color 

 which contrasts only slightly with the surrounding liver tissue 

 by its darker color. It may contain a central yellow nucleus 

 of dead tissue and a narrow outer border of the same character, 

 or the border may be a dark brownish circular line. The entire 

 spot has an indistinct appearance and is flattened or even 



Fig. 66. Liver shoioing diseased foci. 



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