TEXAS FEVER. 
95 
from this malady in cattle shipped from the north are rarely less 
than forty per cent, and frequently seventy per cent., or more. 
The pressing need for some practical method of preventing 
these losses has led the Experiment Stations of Missouri and 
Texas and the Missouri State Board of Agriculture to under¬ 
take the experiments reported herein. 
This cooperative work was begun in 1896, and is still in 
progress. The interests of the cattle industry demand that the 
results obtained up to the present time be presented in official 
form. There is probably much work yet to be done before the 
methods, which can now in careful hands be employed with a 
great degree of success, reach the perfection that is desirable. 
The work reported herein includes: 
I. Experiments to determine whether sterile blood serum of 
immune southern cattle contains any chemical substance of the 
nature of an antitoxin, or toxin that might be utilized practi¬ 
cally in stimulating at least a passive immunity in susceptible 
cattle. 
II. Experiments on immunizing cattle by infection with the 
micro-parasites of the disease by means of tick-infestation . 
III. Experiments on immunizing cattle by infection with 
the micro-parasites of the disease through blood inoculation . 
These will be discussed in the order named. Only a brief 
discussion of the first two lines of work will be given in this 
bulletin.* 
The final results of the experiments on inoculation with 
sterile serum show that such material possesses no protective 
properties. 
Immunizing by tick-infestation can be employed with suc¬ 
cess, but on account of the necessity of maintaining a quaran¬ 
tined pasture, and the necessity of hand-feeding in the case of 
calves of non-immune cows, this method is not as practicable as 
that of blood inoculation. 
* The full details, temperature records, etc., of the first two lines of work will be 
given in the next Annual Report, for the benefit of those who are interested in these mat¬ 
ters from the purely scientific point of view. These records would unnecessarily burden 
this bulletin, which is mainly intended to present results of practical interest. 
