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number of animals (say five to ten), and after experience has 

 been gamed 20 to 30 may be tested at a time. It is not a good 

 plan to test animals when the days are very hot, unless the 

 barn is well ventilated and can be kept so cool that the cows 

 will not become overheated during the test. 



The animals being tested should be fed the same kind of 

 feed, in the same quantity, and at the same time each day of 

 the test; they should also be watered at the same time each 

 day. Likewise the cows should be milked at the regular 

 time during the test. In short the cows that are being tested 

 should be kept under exactly the same conditions during the 

 two days of the test. 



If the animals to be tested are not kept in their stalls over 

 night have them placed in their stalls at 5 o'clock in the 

 morning. Begin taking and recording their temperatures at 6 

 o'clock and repeat this every two hours until 6 or 8 o'clock in 

 the evening. At 8 or 10 o'clock in the evening inject sub- 

 cutaneously 2 to 3 c.c. of tuberculin into each adult animal 

 weighing 1,000 pounds or less; if the animal weighs 1,200 to 

 1,500 inject not less than 3 c.c; for calves use at least Ice. 

 These doses apply to that form of tuberculin that is ready for 

 use and not to the concentrated form. 



The most convenient place for injecting the tuberculin is 

 on the side of the neck or at the upper part of the shoulder. 

 The best form of hypodermic syringe is one that permits the 

 needle to slip on or into the barrel, and can be thoroughly 

 sterilized by steam, hot water or hot air. 



On the following morning begin to take the temperatures at 

 6 a. m. and repeat the same every two hours until 6 or 8 

 p. m., as on the previous day. 



Now compare the temperature records for the two days. If 

 the temperatures are two or more degrees higher on the 

 second day, for three or more consecutive readings or records, 

 than on the first day the animal is sard to have "reacted." In 

 other words the reaction says that the animal has tubercu- 

 losis. If the temperature rises for one or two readings, then 

 falls for one or two readings and then rises, such fluctuations 

 will indicate that the animal is more or less suspicious and 



