INFECTIOUS ENTERO-HEPATITIS OF TURKEYS 123 
7% to % of an inch in diameter and may be isolated and few in num- 
ber or numerous and closely associated, even coalescent. Their color 
varies from a yellowish to a yellowish-green. These areas of ne- 
crosis extend more or less deeply into the structure of the liver and 
result from plugging of the smaller arterioles with the parasites and 
cellular debris. They are not always of a homogeneous color, but 
may appear mottled with small areas of approximately normal liver 
tissue. No elevation above the liver surface is in evidence as may 
be the case in tuberculosis or sarcomatosis of the liver and the tend- 
ency is rather to a slight depression beneath the capsule. The liver 
is often enlarged to a considerable degree and congested. 
In very acute cases the ceca show slight evidence of exudate but 
are more or less inflamed while the liver is free of lesions. Other 
areas of the intestine, especially the duodenum and rectum, harbor 
the causative parasite and may exhibit congestion of the mucous 
membrane, hemorrhagic points or even spots of necrosis. However, 
the ceca and liver are the main seats of disease and more to be 
relied upon for diagnostic evidence. Infrequently the morbid process 
within the lumen of the cecum extends through the mucosa, sub- 
mucosa, muscular layers and serous coat causing perforation and exu- 
dation into the peritoneal cavity leading to peritonitis or extensive 
adhesions of the cecum to the surrounding loops of intestine. This 
condition is apparently due to the action of invading bacteria since 
the protozoal organisms have not been demonstrated in these sec- 
ondary lesions. 
Microscopically the cecal exudate is found to be composed of 
protozoal bodies, exfoliated mucosa cells in various stages of degen- 
eration, connective tissue shreds, blood cells and an amorphous de- 
tritus. The cecal wall is greatly thickened due to infiltration and 
connective tissue hypertrophy. The mucosa shows extensive de- 
generative changes or is absent in areas. Depending on the depth 
of the ulceration, the circular or longitudinal muscular layers show 
more or less infiltration with small round cells and congestion, which 
may extend to the serosa. In the liver the necrotic foci show vary- 
ing stages of cell degeneration and are surrounded by a congested 
area. Walling off of the affected spots is not well marked or is 
totally absent. Small round cells, protozoal organisms and nuclear 
remnants are distinguished in the amorphous necrotic material. In 
both the intestinal membrane and in the liver the protozoa occur 
either singly or in groups between the epithelial, or parenchymatous 
cells where they may be enclosed in a connective tissue network. 
