514 BOARD OF AGRICULTURE. [Pub. Doc. 



so that native cattle when grazing or resting upon the infected 

 places contracted the disease known to the United States govern- 

 ment as Texas fever, but to farmers as " red water," "bloody 

 murrain " or " tick fever." 



The actual cause of the disease (the micro-parasite Pyrosoma 

 higeminum. Smith) was demonstrated in 1889. The proof that 

 cattle ticks {Boophilus bovis TRiley sp.) Curtice) carried this 

 disease from one animal to another followed a year or two later. 



A complete cycle of an outbreak of this disease is embraced 

 between the time that it leaves an animal capable of infecting 

 ground it passes over, until it destroys or runs its course in an 

 attacked animal. 



In their investigations, the Bureau authorities completely dem- 

 onstrated the fact that southern cattle without ticks were inca- 

 pable of spreading disease ; that young ticks hatched from eggs 

 laid by ticks plucked from southern cattle produced the disease 

 when placed on susceptible northern cattle in from thirteen to 

 twenty-one or more days, depending upon the age of the cattle 

 and the temperature of the weather. 



They also demonstrated that blood taken from affected cattle 

 produced disease in young cattle, and death in older cattle in from 

 thirteen to twenty-one days, but on one occasion eight days and 

 on another nine days. It has been demonstrated that the appear- 

 ance of the disease in northern cattle is entirely dependent upon 

 the life-history of the cattle tick. For example : southern cattle 

 passing through stock yards, riding in cars, driven over highways 

 or pasturing, lose the ticks, which usually infect them, upon the 

 ground. These ticks lay eggs beginning in from one to four days, 

 and continuing a week. Incubation begins at once, and continues, 

 depending mainly upon heat and moisture, from three to six weeks. 

 Since the ovipositing is prolonged, the hatching is also prolonged. 

 After a day or two the recently hatched ticks scatter somewhat 

 and crawl upwards on the grass blades, sticks, or whatever is first 

 met with. They are then ready to attach themselves to cattle, 

 from which alone they can get the sustenance necessary to carry 

 them to maturity. They may endure, however, in this condition 

 for a practically indefinite time, three to four months, unless 

 benumbed by the chilling frosts and the low average temperature 

 of the fall months. 



The home of these ticks, the country where they are practically 

 perpetually present, unless eradicated by the efforts of farmers or 

 agricultural processes, is coincidental with the area described 

 above as containing cattle which may carry disease to northern 

 cattle. The tick does not seem to be able to stand climatic con- 



