The author prepared a tuberculin sample using synthetic medium for the test material in7this experiment.
For the test animals, guinea pigs, healthy calf sensitized with heat killed tubercle bacilli, naturally infected dairy cattle, goat, and calf were used.
A reduced reactivity to tuberculin was observed when the second tuberculin test was done within 28 days after the first. The results obtained are summarized as follows.
1. The experimental HCSM tuberculin was shown the similar activities as the control products of standard tuberculin.
2. The potency of the experimental tuberculin preserved at 5°C in refrigerator maintained the activity for three years.
3. By the intradermal test, the experimental tuberculin was proved to be specific to detect tuberculous dairy cattle’s and goats.
4. The appearance of skin reaction to tuberculin in naturally infected dairy tattles, goat and beef tattles was soft and diffuse swellings or circumscribed swellings accompanied by in duration.
5. In the case of observing tuberculous dairy cattle’s, goats and beef cattle`, as the criterion of the reaction to the caudal fold test, results were taken as positive when findings are either hard and circumscribed or soft and diffuse swellings of 3 mm at least in size.
6. The acid fast organisms isolated from tuberculin positive animals were identified mostly as M. tuberculosis var. bovis.
7. When the tuberculin test was repeated in the tuberculin positive animals, the reactivity decreased rapidly, lasting 4 weeks at least.
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