[Code of Federal Regulations]
[Title 9, Volume 1]
[Revised as of January 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 9CFR113.55]

[Page 645-646]
 
                  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. 113.55  Detection of extraneous agents in Master Seed Virus.

    Unless otherwise prescribed in a Standard Requirement or in a filed 
Outline of Production, each Master

[[Page 646]]

Seed Virus (MSV) shall be tested as prescribed in this section. A MSV 
found unsatisfactory by any prescribed test shall not be used. A serial 
of biological product shall not be released if produced from a MSV that 
is found unsatisfactory by any prescribed test.
    (a) At least a 1.0 ml aliquot per cell culture of MSV shall be 
dispensed onto monolayers (at least 75 cm\2\ in area) of:
    (1) Vero (African green monkey kidney) cell line;
    (2) Embryonic cells, neonatal cells, or a cell line of the species 
for which the vaccine is recommended; and
    (3) Embryonic cells, neonatal cells, or a cell line of the species 
of cells in which the MSV is presently being propagated if different 
than prescribed in paragraphs (a)(1) and (a)(2) of this section. Cell 
lines used shall have been found satisfactory when tested as prescribed 
in Sec. 113.52 and primary cells used shall have been found 
satisfactory when tested as prescribed in Sec. 113.51. If the MSV is 
cytopathic for or causes hemadsorption in the cells in which it is to be 
tested, the MSV shall be neutralized with monospecific antiserum 
supplied or approved by Animal and Plant Health Inspection Service 
(APHIS) or counteracted by a method approved by APHIS.
    (b) At least one monolayer of each cell type used in the test shall 
be maintained as an uninoculated control.
    (c) Each monolayer shall be maintained at least 14 days.
    (d) Cells shall be subcultured at least once during the maintenance 
period. All but the last subculture shall result in at least one new 
monolayer at least 75 cm\2\. The last subculture shall meet the minimum 
area requirement specified in Sec. Sec. 113.46 and 113.47.
    (e) Monolayers shall be examined regularly throughout the 14-day 
maintenance period for evidence of cytopathogenic agents. If evidence of 
a cytopathogenic agent is found, the MSV is unsatisfactory.
    (f) At the conclusion of the 14-day maintenance period, monolayers 
shall be tested for:
    (1) Cytopathogenic and/or hemadsorbing agents as prescribed in Sec. 
113.46;
    (2) Extraneous agents by the fluorescent antibody technique as 
prescribed in Sec. 113.47.

[50 FR 444, Jan. 4, 1985, as amended at 56 FR 66784, Dec. 26, 1991]

                         Live Bacterial Vaccines