476 DISEASES OF CATTLE. 



generation and perish. The functions of the liver are thereby com- 

 pletely suspended and death is the result. This enormous destruc- 

 tion of corpuscles takes place to a large extent in the kidneys, ^vhere 

 a great number of corpuscles containing the parasites are always 

 found in acute cases. T]iis accounts largely for the blood-colored 

 urine, or red Avater, 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 up and pass into the urine. 



Symptoms. — After a period of exposure to infected soil, which 

 may vary from 13 to 90 days, and which will be more fully discussed 

 under the subject of cattle ticks as bearers of the Texas-fever para- 

 site, the disease first shows itself in dullness, loss of appetite, and a 

 tendency to leave the herd and stand or lie down alone. A fcAv days 

 before these symptoms appear the presence of a high fever may be 

 detected by the clinical thermometer. The temperature rises from 

 a normal of 101° to 103° F. to 106° and 107° F. There seems to be 

 little or no change in temperature until recovery or death ensues. 

 The period of high temperature or fever varies considerably. As it 

 indicates the intensity of the disease process going on within, the 

 higher it is the more rapid the fatal end. When it does not rise 

 above 101° F. the disease is milder and more prolonged. 



The bowels are niosth' constipated during the fever; toward the 

 end the feces may become softer and rather deeply tinged with bile. 

 The urine shows nothing abnormal during the course of the disease 

 until near the fatal termination, when it may be deeply stained with 

 the coloring matter cf the blood. (Hemoglobinuria; see PI. XLV, 

 fig. 3.) Although this symptom is occasionally observed in animals 

 which recover, yet it may generally be regarded as an indication of 

 approaching death. The pulse and respiration are usually unich 

 more rapid than during health. 



Other symptoms in addition to those mentioned have been de- 

 scribed by observers, but they do not seem to be constant, and only 

 those described above ai-e nearly always present. As the end ap- 

 proaches emaciation becomes very marked, the blood is very thin 

 and watery, and the closing of any wound of the skin by clots is re- 

 tarded. The animal manifests increasing stupor and may lie down 

 much of the time. Signs of delirium have been observed in some 

 cases. Death occurs most frequently in the night. 



The duration of the disease is very variable. Death may ensue 

 in from three da3^s to several weeks after the beginning of the fe\ er. 

 Those that recover ultimately do so very slowly, owing to the 

 great povei'ty of the blood in red coi'puscles. The fltv^h is regained 

 but vei-y gi-adually, and the animal may be subjected to a second. 



