158 COMMON DISEASES. 



inclined to kick just as the operator steps out of the stall. This 

 can be prevented by an assistant giving the tail a vigorous pull 

 sidewise. 



Two periods. — The time of each test is divided into two 

 periods: (A) the day before, and (B) the day after injection. 

 During (A) the temperatures are taken at 8 and 10 a. m., then at 

 2, 6 and 8 p. m. The tuberculin is then given by hypodermic in- 

 jection at 9 p. m. During (B) the temperatures are taken at 6, 

 8, io and 12 a. m., and 2, 4, 6, and 8, and sometimes 10 p. m. 



The thermometer. — Self registering thermometers, commonly 

 known as fever or clinical thermometers, are necessary for this 

 work, and the)' should all be correct between 100 and 105 F. All 

 thermometers used should first be tested on the same animal and 

 the records compared. Any thermometer which varies one de- 

 gree or more from the records shown by the others should be dis- 

 carded. 



Temperatures are taken by inserting the thermometer into the 

 rectum or vagina, usually the former. The following simple de- 

 vice has been found very satisfactory. A rubuer band is fitted 

 with a wire hook at one end and ring at the other. The middle 

 of the band is then connected with the top of the thermometer 

 by a stout string about 5 inches long. The thermometer is in- 

 serted and the band hooked around the base of tail. This per- 

 mits the operator to use a large number of thermometers and 

 prevents them from falling to the floor and breaking. 



Dose. — The dose is about 1 c. c. or J4 dram Bureau tuber- 

 culin per 500 pounds live weight. The doses may be measured 

 directly from the bottle, or one or two bottles at a time can be 

 emptied into a small vessel from which the doses can be more 

 conveniently poured into the small graduate. It is very conveni- 

 ent to use a syringe with graduated piston rod or barrel and 

 measure the doses in the syringe. 



Cautions. — The cattle must be kept under the same condi- 

 tions as nearly as possible on both days; i. e., watered at the same 

 hours and fed at the same hours on each day, given as nearly 

 as possible the same amounts and treated alike on the two davs in 

 every respect. 



There are several possibilities of error if operator is not care- 



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