Protozoan Cattle Fever. Texas Fever. Paludism of Cattle. 555 



be seen as yellow cylindroid casts sometimes bifurcated to repre- 

 sent the union of the two canals. If stained in Khrlich's acid 

 hsematoxylin, the necrotic elements refuse to take the stain so 

 that the contrast between the dead and the living tissues is en- 

 hanced. Fatty degeneration is common in the liver of healthy 

 beef cattle so that this is less significant than the congestion of 

 the acini, and the phenomenal distension of the radical gall ducts 

 with inspissated bile. 



T\y^ gall bladder \s Xis\x2Xi.y full (^ pint to i quart or more), 

 and its mucous membrane congested and sometimes petechiated. 

 The bile is thick and viscid, like tar, it may be yellowish green, 

 darkening on exposure and contains haematoidin crystals and 

 abundance of flocculi showing bright yellow or orange by trans- 

 mitted light and reddish brown by reflected light. 



The spleen is always enlarged, often enormously so. From an 

 average weight of 1.5 lb. to 1.7 lb. for a 1000 lbs. ox, it will rise 

 to 2, 7 or even 10 lbs. One mea.sured 27 inches long by 7^^ 

 inches wide and in the centre 3 inches thick (Rauch). Even in 

 apparent health the Gulf coast cattle have spleens averaging 

 about 2j^ lbs. 



The spleen is gorged with blood which appears purple as seen 

 through the stretched and attenuated capsule, and darker pete- 

 chial spots are found at intervals. When cut into, the pulp alone 

 appears dark, brownish red, grumous, and showing under the 

 microscope many red blood cells, larger cells granular and under- 

 going fatty degeneration, yellow flocculi, crystals of hsematoidin, 

 and granules of black pigment. It is the excess rather than the 

 nature of these agents that is significant. The pulp may be 

 pressed or washed out, bringing the trabeculse and Malphigian 

 bodies into view. 



The kidneys are most seriously affected in acute and rapidly 

 fatal cases. There may be oedema, with blood staining and even 

 extravasation on their lower surface and in the adipose tissue. 

 The gland may be enlarged and the cortical substance congested 

 of a dark brownish red or black. Its capillaries are gorged with 

 red globules in which the piroplasmata are very numerous. The 

 medullary portion is much paler, and with fatty granules in the 

 epithelium, and oil globules in the tubules. The renal pelvis is 

 more or less petechiated and marked by extravasations. 



