254 



Notice that out of 1,500 animals inoculated by him 3^ 

 per cent, were lost by inoculation fever and less than 7 

 per cent, by exposure to tick inoculation after recovery 

 from defibrinated blood inoculation. Remember that 

 the vast majority of the cattle inoculated by him were 

 placed in large pastures on ranches where little or no 

 attempt was made to keep off ticks; and that in many 

 previous instances Northern-bred cattle under like con- 

 ditions had a mortality as high as 50 to 90 per cent. 



College Station, August 5, 1001. 



Dr. C. A. Gary, Auburn, Ala. 



Dear Doctor — I have your letter of the 2nd in 

 regard to our experiments with Texas fever. I am pre- 

 paring a bulletin on the subject now and hope to have it 

 off within six weeks. I have inorulated about 1,500 

 calves. These run all the way from a few months old to 

 two years of age. I cannot tell you without several 

 hours' work just how many of each age. I may say^ 

 however, that the best age is about one year old. The 

 best time of the year is any time from November to 



March. 



We consider one cubic centimeter as a standard dose. 

 We use all the way from one-half of one cc to two cc, 

 but one cc is a standard dose. We take the blood direct 

 from the jugular vein of any Texas-raised animal that 

 is in good health. We usually take something that is 

 two or three years old, so as to avoid the transmission 

 of tuberculosis. 



As a general rule, we make two inoculations. I think, 

 however^ that one is enough, but we use two merely to be 

 sure of an infection. If the time between inoculation 

 and exposure to ticks is several months, I favor two in- 

 oculations. 



