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WHAT IS TEXAS FEVER ? 



In various parts of the country this disease is known 

 by different names; it has been called Texas fever, ac- 

 climating fever, Southern fever, tick fever, Spanish 

 fever, red water, hsematuria, black water, murrain, dry 

 murrain, yellow murrain, bloody murrain, hollow-horn 

 and hollow-tail. 



Texas fever is caused by a very small animal parasite 

 (Pi/rosoma higeminumj Smith) which was discovered 

 by Theobald Smith in 1889. Its chief place of living is 

 in the red blood cells of cattle. In some condition it 

 lives in the cattle tick and is carried from immune cat- 

 tle or cattle sick T\ith Texas fever, to non-immune or sus- 

 ceptible cattle by the tick. In this transmission of the 

 microparasite from the diseased to the healthy animals, 

 it passes through two generations of ticks. The female 

 tick abstracts blood from its host; falls to the ground, 

 deposits a large number of eggs that hatch in 14 to 45 

 days, and the young seed ticks get upon susceptible cat- 

 tle and inoculate them. In many cases the fever appears 

 in the cattle about the time the young ticks molt the 

 second time; then the young ticks are about one-eighth 

 of an inch lonor, and the careless observer mav declare 

 there are no ticks on the animal sick with Texas fever. 

 It may be here stated that this micro-parasite has two 

 hosts (cattle and ticks of two generations) and pos- 

 sibly can not live any^^here outside these two hosts. 

 At least its existence in other hosts or places have not 

 been discovered. In some respects it resembles the ma- 

 lerial parasite of man, but its stages of development, 

 are not as well known as those of the ma- 

 terial miscro-parasite. Yet some things are known of 

 its form and life history in the red blood cells of cat- 

 tle, and in the plasma of the blood. In mild cases of 



