101 



dark. The designation is not a good one, however, be- 

 cause this discoloration of tlie liead may come from 

 other causes than this particular disease, and some- 

 times in this disease the head does not become dark. 

 As yet, a good popnlar. descriptive name has not been 

 suggestd. 



Infections entero-hepatitis is caused by protozoa, 

 minute animal parasites so small and simple that they 

 can scarcely be distinguished from some members of 

 the vegetable kingdom. 

 These gain access to the di 

 gvstive tract of turkeys and 

 enter the caeca, which are 

 two prolonged pouches 

 .springing from the union of 

 the small and hirge intes 

 tines. Within the caeca, 

 the protozoa of this disease 

 irritate the mucous mem 

 brane and cause il to be 

 come tliickenetl .iiid ulcer 

 ated. Tlie caeca also be- 

 come distended and some 

 times extraordinarily large. 

 The protozc'a penetrate to 

 tlie liver and cause tliere the 

 formation of yellowish spots 

 resembling small abscesses 

 tilled with cheesy pus. This 

 appearance results from the 

 death of localized areas of 

 liver tissue. The surround 

 iutf parts of the liver are full 

 of blood, and the entire organ is considerably enlarged 



Cmca of Healthy Turkey. 



The central tube is the small in- 

 testine, the food passing down- 

 ward in the direction of the arrow. 

 At the junction of the caeca with 

 the intestine, the food is drawn 

 into the cieca by suction. The 

 thicknes", of the ctecal wall is 

 shown in a: One-half natural 

 size (Moore). 



