442 INFECTIOUS DISEASES DUE TO PROTOZOA 



Symptoms. — After a period of incubation of eight to ten 

 days following infestation with ticks, symptoms of fever 

 appear. The temperature ranges from 104.9° to 108° F., 

 the patient is dull, stupid (in rarer instances may show 

 excitement), the muzzle dry and hot and the appetite is 

 impaired or fails. Quite often the patients assume unnatural 

 attitudes when standing or lying. The mucous membranes 

 are icteric, pulse rapid, breathing dyspneic, bowels consti- 

 pated and the feces, which later becomes softer, tinged with 

 blood and bile. On the skin of the scrotum (udder), inner 

 surface of the thighs, escutcheon and sometimes over the 

 whole body ticks may be felt and seen. Toward the end of the 

 attack, and especially marked in fatal cases, is the appear- 

 ance of hemoglobinuria, the urine assuming a claret-wine 

 color. The blood is anemic (number of red corpuscles sinks 

 from eight to less than three million), poikilocytes appear 

 and numbers of pear-shaped or round protozoa can be seen 

 in the red blood corpuscles. 



Necropsy. — In acute cases the condition of the cadaver is 

 usually good, but where the course has been protracted it is 

 emaciated. Ticks are found on the skin, especially in the 

 region of the scrotum (udder), inner surface of the thighs and 

 escutcheon. The subcutaneous tissue is usually anemic and 

 icteric. The spleen is enlarged, often weighing six or seven 

 pounds and its parenchyma has become a dark, purple colored, 

 disintegrated mass. The liver is enlarged, has lost its natural 

 brown color and is yellow on its surface. When incised it 

 shows a mahogany-brown color; from fatty degeneration 

 the color is still lighter yellow. The gall-bladder is distended 

 with flaky bile mixed with mucus of a viscid, stringy con- 

 sistency. The urinary bladder is filled with red urine, the 

 shades varying from pale red to a deep red. The kidneys 

 are hyperemic, the lungs are intact and the serous coverings 

 of the heart show ecchymoses. 



Diagnosis. — In the United States Texas fever might be 

 confused with anthrax, black-leg and hemorrhagic septi- 

 cemia. The presence of the ticks (in non-tick-infested 

 districts) on the skin and the microscopic examination 

 of the blood should clear away all doubt. Clinically, the 



Digitized by Microsoft® 



