Bottle of dried Johnin PPD Sample. Used by Commonwealth Serum Laboratories (CSL) Ltd, Parkville, Victoria, 1947. Johnin is a product used as a diagnostic agent, analogous to tuberculin but made from mycobacterium paratuberculosis (the causative organism of Johne's disease) grown in a broth medium containing mycobacterium phlei (timothy hay bacillus); used as an allergen to provoke reactions in infected animals.

Physical Description

Glass jar with glass lid, bound in plastic. Contains brown powder in clumps. Paper label.


Example of CSL work on tuberculosis

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