338 TEXAS FEVER 
As evidence of the diminution of the number of corpuscles within 
the body these authors point (1) to the loss of hemoglobin through the 
kidneys, (2) to the overproduction of bile which is abnormal in the 
abundance of pigment and (3) to the actual observation of their 
destruction by the micro-parasite under the microscope. 
The regeneration of blood corpuscles is indicated perhaps by the 
count, but more surely by the forms of the corpuscles themselves. 
The abnormal forms are the very large corpuscles, “punctate” forms 
and lastly the diffuse stained or “tinted” forms and the erythroblasts. 
The first of these may appear when the blood count reaches 3,000,000 
and the other forms when it is still lower. These various forms, how- 
ever, are probably embryonic or immature corpuscles, which are 
forced prematurely into the circulation by the blood producing organs 
in trying to overcome the rapid destruction of corpuscles by the 
parasite. The action of the disease upon the leucocytes or the defen- 
sive activities of the white corpuscles in combating the parasite of 
Texas fever have not been determined. In the work thus far per- 
formed and reported, they have received little attention. Suffice it 
to say that they have not been in evidence in this conflict and proba- 
bly take little or no part in the morbid changes of Texas fever. 
Diagnosis. Texas fever is easily diagnosed by the presence of its 
specific parasite. Its symptoms and lesions are sufficient for diag- 
nostic purposes in the typical cases. Texas fever is to be differen- 
tiated from anthrax and poisoning. The possible existence of Ana- 
plasmosis may necessitate its differentiation from that infection. 
The lesions are not simulated by any other disease of cattle, 
although the enlarged, dark spleen may suggest anthrax and in a hasty 
diagnosis the two may be confused. From the fact that all animals 
exposed together usually come down with the disease together 
poisoning may be suggested, but here again a study of the symptoms 
and lesions are sufficient to eliminate toxic disorders. 
Prevention. The discovery of the specific cause of Texas fever and 
of the cattle tick as the common means of its transmission has reduced 
the preventive measures to a direct warfare against the tick. The 
National government has determined the territory in which the tick 
naturally exists and from which cattle, on account of the parasite, 
cannot be shipped to uninfected districts, except under certain very 
restricted conditions. (See regulations of: the Bureau of Animal 
Industry for shipping cattle). Likewise susceptible northern cattle 
