It is possible to reduce the resistance of guinea pigs to tuberculosis by x-ray exposures, so that when animal inoculation is required for a diagnosis a much quicker result may be had than by the use of normal animals. In renal tuberculosis when it is necessary to resort to the use of animals, it ordinarily requires from 5 to 7 weeks, while by the use of x-rayed guinea pigs the diagnosis can be made in from 8 to 10 days. The resistance can be sufficiently lowered by one massive dose of x-ray administered either shortly before or after the inoculation of the material to be tested. The lesions are so marked in these animals that the diagnosis is certain after the interval indicated above.

This content is only available as a PDF.