INFECTIOUS DISEASES OF CATTLE. 431 



The acute disease is fatal in most cases, and the fatality is due not so 

 much to the loss of blood corpuscles as to the difficulty which the or- 

 gans have in getting rid of the waste products arising from this whole- 

 sale destruction. How great this may be a simple calculation will 

 serve to illustrate. If we take a steer weighing 1,000 pounds, the blood 

 in its body will amount to about 50 pounds, if we assume that the blood 

 represents one-twentieth of the weight of the body, a rather low esti- 

 mate. According to experimental determination at the Bureau Station, 

 which consists in counting the number of blood corpuscles in a given 

 quantity of blood from day to day in such an animal, the corpuscles con- 

 tained in from 5 to 10 pounds of blood may be destroyed within twenty- 

 four hours. The remains of these corpuscles and the coloring matter 

 in them must either be converted into bile or excreted unchanged. The 

 it-suit of this effort on the part of the liver causes extensive disease 

 of this organ. The bile secreted by the liver cells contains so much 

 solid material that it stagnates in the finest bile canals and chokes these 

 up completely. This in turn interferes with the nutrition of the liver 

 cells and they undergo fatty degeneration and perish. The functions 

 of the liver are thereby completely suspended and death is the result. 

 This enormous destruction of corpuscles takes place to a large extent 

 in the kidneys, where a great number of corpuscles containing thepara- 

 >ite> arc always found in acute cases. This accounts largely for the 

 blood-colored urine or red water which is such a characteristic feature 

 of Texas fever. The corpuscles themselves are not found in the urine; 

 it is the red coloring matter or hemoglobin which leaves them when they 

 break np and passes into the urine. 



Xymptom*. After a period of exposure to infected soil, which may 

 vary from thirteen to ninety days, and which will be more fully dis- 

 1 im-t her on, under the subject of cattle ticks as bearers of the 

 ver parasite, the disease first shows itself in dullness, loss of 

 appetite, and a tendency to leave the herd and stand or lie down alone. 

 A few days before these symptoms appear the presence of r, high fever 

 may be detected by the clinical thermometer. The temperature i 

 from a normal of 101Q-103O F. to 10<P and 107 F. There seems to be 

 little or no change in temperature until recovery or deatli ensues. The 

 period of high temperature or fever varies considerably. As it indi- 

 cates the intensity of the disease process going on within, the higher it 

 is t lie more rapid the fatal end. When it does not rise above 104 F. the 

 disease is milder and more prolonged. 



The bowels are mostly constipated during the fever; towards the end 

 the tcces may become softer and rather deeply tinged with bile. The 

 mine shows nothing abnormal during the course of the disease until 

 near the fatal termination, when it may be deeply stained with the'col- 

 oring matter of the blood. (Hemoglobinuria; see Plate XLIII, Fig. 3.) 

 Although this symptom is occasionally observed in animals which 

 reeo\er. yet it may generally be regarded as an indication of approach- 



