Tuberculin, Intradermic.

CFR · 2024-01-01 · US · Title 9

Tuberculin, Intradermic, is a filtrate produced from cultures of Pn, C, and Dt strains of (a) (1) Final container samples of completed product shall be tested for viable bacteria and fungi as prescribed in § 113.26. (2) A 20 ml sample shall be centrifuged and the sediment examined (b) (c) (1) The guinea pigs shall be sensitized with a sterile heat-killed suspension of equal amounts of strains Pn, C, and Dt of (2) The guinea pigs shall be prepared for sensitivity testing at least 4 hours prior to the injection of tuberculin. The entire abdominal and flank areas shall be clipped, a depilatory agent applied for 5-10 minutes, the area rinsed with warm water, and dried. (3) Dilutions of 1:100, 1:200, and 1:400 shall be prepared with the Reference Tuberculin and the unknown tuberculin. Three test sites on each side of and equidistant from the abdominal midline shall be chosen on each guinea pig. Using a tuberculin syringe and needle, 0.05 ml of each dilution shall be injected intradermally at one of the test sites which has been randomly selected for the dilution. (4) The sensitivity of the tuberculins shall be determined 24 hours after injected by measuring the area of erythema. Measurements in millimeters shall be made anterior of the greatest diameter and perpendicular to the first measurement. The square millimeter shall be calculated by multiplying the two measurements. (5) The total area of response for each tuberculin tested shall be determined by adding the areas of erythem

official document · source cfr-2024 · id 9:§ 113.406