[Code of Federal Regulations]
[Title 9, Volume 1]
[Revised as of January 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 9CFR113.101]
[Page 623-624]
TITLE 9--ANIMALS AND ANIMAL PRODUCTS
CHAPTER I--ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF
AGRICULTURE
PART 113--STANDARD REQUIREMENTS--Table of Contents
Sec. 113.101 Leptospira Pomona Bacterin.
Leptospira Pomona Bacterin shall be produced from a culture of
Leptospira pomona which has been inactivated and is nontoxic. Each
serial of biological product containing Leptospira pomona fraction shall
meet the applicable requirements in Sec. 113.100 and shall be tested for
purity, safety, and potency as prescribed in this section. A serial
found unsatisfactory by any prescribed test shall not be released.
(a) Purity test. Final container samples of completed product from
each serial and each subserial shall be tested for viable bacteria and
fungi as provided in Sec. 113.26.
(b) Safety test. Bulk or final container samples of completed
product from each serial shall be tested for safety as provided in
Sec. 113.38.
(c) Potency test. Bulk or final container samples of completed
product shall be diluted with physiological saline so that each 0.25 ml
contains not more than 1/800th of the dose recommended on the label and
shall be tested for potency, using the two-stage test provided in this
paragraph.
(1) Vaccinates. Inject each of at least 10 but not more than 12
young adult hamsters, each weighing 50 to 90 grams, with 0.25 ml of the
diluted bacterin either subcutaneously or intramuscularly, in accordance
with the label recommendations for use.
(2) Controls. Retain at least 10 but not more than 12 additional
hamsters from the same group as unvaccinated controls.
(3) Challenge. From 14 to 18 days postvaccination, challenge each of
10 vaccinates and each of 10 controls intraperitoneally with a
suspension of virulent Leptospira pomona organisms, using a dose of 10-
10,000 hamster LD50 as determined by titration.
(4) Post-challenge period. Observe the vaccinates and controls for
14 days post-challenge and record all deaths. If eight or more controls
die of leptospirosis, the test is valid and the results shall be
evaluated according to the following table:
[[Page 624]]
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Cumulative total Cumulative total
Number of Cumulative number dead hamsters for dead hamsters for
Stage vaccinates of vaccinates satisfactory unsatisfactory
serial serial
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1............................... 10................ 10................ 2 or less......... 5 or more.
2............................... 10................ 20................ 5 or less......... 6 or more.
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(5) If three or four vaccinates die in the first stage, the second
stage shall be conducted in a manner identical to the first stage.
(6) If the second stage is used, each serial shall be evaluated
according to the second part of the table. On the basis of cumulative
results, each serial shall either pass or fail.
[39 FR 16862, May 10, 1974, as amended at 40 FR 20067, May 8, 1975; 45
FR 40100, June 13, 1980. Redesignated at 55 FR 35562, Aug. 31, 1990, as
amended at 56 FR 66785, Dec. 26, 1991]