Till-: MORE COMMON AlI^MICNTS OF CATTLE 423 



the second day every two hours, beginning at 6 a. m. 

 The temperatures are taken by inserting a self-register- 

 ing clinical thermometer into the rectum or the vagina. 

 If the temperature rises more than 2° above the normal 

 range shown on the first day, the animals may be pro- 

 nounced tuberculous, and if the rise is 1.5° to 2°, they 

 should be regarded as suspicious and reserved for further 

 test. In a typical reaction the temperature gradually 

 rises for four hours or more, until it attains a maximum 

 and then it gradually falls. 



Although the testing of cattle is, in a sense, a simple 

 work, there are many things about it that the unskilled 

 may fail to notice, hence the importance of having it 

 done only by qualified men. Cattle owners have fre- 

 quently paid dearly for the mistake of unskilled oper- 

 ators. Tuberculin is now made in a commercial way 

 by certain manufacturing firms from whom it may be 

 obtained directly or through the medium of druggists. 

 The dose of Bureau tuberculin approximately is J4 of 3- 

 dram for each 500 pounds of live weight. The testing 

 should not, except in special cases, be more frequent 

 than once each six months or the system may reach a 

 condition in which it will fail to respond. The tuber- 

 culin does not furnish an absolutely infallible test, as 

 when the disease is in the most advanced stages there 

 may be no response, and yet the percentage of such 

 errors is but a fractional part of i per cent. 



The losses resulting from tuberculosis in cattle have 

 been very great. There is no means of estimating them 

 correctly, for the reason, among others, that they occur 

 in so many different ways. There is, first, the direct 

 loss from death in herds yet untested and from animals 

 found infected and condemned ; second, the less direct 

 loss from ill-doing on the part of many of the afflicted 

 animals; third, the indirect loss in swine which have 

 been affected by tuberculous milk; fourth, the loss from 

 what ma}' be termed deterrent influences to continu- 



