[Code of Federal Regulations]
[Title 9, Volume 1]
[Revised as of January 1, 2008]
From the U.S. Government Printing Office via GPO Access
[CITE: 9CFR3.28]

[Page 62-63]
 
                  TITLE 9--ANIMALS AND ANIMAL PRODUCTS
 
  CHAPTER I--ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF 
                               AGRICULTURE
 
PART 3_STANDARDS--Table of Contents
 
 Subpart B_Specifications for the Humane Handling, Care, Treatment, and 
               Transportation of Guinea Pigs and Hamsters
 
Sec. 3.28  Primary enclosures.

    All primary enclosures for guinea pigs and hamsters shall conform to 
the following requirements:
    (a) General. (1) Primary enclosures shall be structurally sound and 
maintained in good repair to protect the guinea pigs and hamsters from 
injury. Such enclosures, including their racks, shelving and other 
accessories, shall be constructed of smooth material substantially 
impervious to liquids and moisture.
    (2) Primary enclosures shall be constructed and maintained so that 
the guinea pigs or hamsters contained therein have convenient access to 
clean food and water as required in this subpart.
    (3) Primary enclosures having a solid floor shall be provided with 
clean bedding material.
    (4) Primary enclosures equipped with mesh or wire floors shall be so 
constructed as to allow feces to pass through the spaces of the mesh or 
wire: Provided, however, That such floors shall be constructed so as to 
protect the animals' feet and legs from injury.
    (b) Space requirements for primary enclosures acquired before August 
15, 1990--(1) Guinea pigs and hamsters. Primary enclosures shall be 
constructed and maintained so as to provide sufficient space for each 
animal contained therein to make normal postural adjustments with 
adequate freedom of movement.
    (2) Guinea pigs. In addition to the provisions of paragraph (b)(1) 
of this section, the following space requirements are applicable to 
primary enclosures for guinea pigs:
    (i) The interior height of any primary enclosure used to confine 
guinea pigs shall be at least 6\1/2\ inches.
    (ii) Each guinea pig housed in a primary enclosure shall be provided 
a minimum amount of floor space in accordance with the following table:

------------------------------------------------------------------------
                                                                Minimum
                                                               space per
                 Weight or stage of maturity                  guinea pig
                                                                (square
                                                                inches)
------------------------------------------------------------------------
Weaning to 350 grams........................................          60
350 grams or more...........................................          90
Breeders....................................................         180
------------------------------------------------------------------------

    (3) Hamsters. In addition to the provisions of paragraph (b)(1) of 
this section, the following space requirements are applicable to primary 
enclosures for hamsters:
    (i) The interior height of any primary enclosure used to confine 
hamsters shall be at least 5\1/2\ inches, except that in the case of 
dwarf hamsters, such interior height shall be at least 5 inches.
    (ii) A nursing female hamster, together with her litter, shall be 
housed in a primary enclosure which contains no other hamsters and which 
provides at least 121 square inches of floor space: Provided, however, 
That in the case of dwarf hamsters such floor space shall be at least 25 
square inches.
    (iii) The minimum amount of floor space per individual hamster and 
the maximum number of hamsters allowed in a single primary enclosure, 
except as provided for nursing females in paragraph (b)(3)(ii) of this 
section, shall be in accordance with the following table:

------------------------------------------------------------------------
                                           Minimum space per
                                            hamster (square     Maximum
                   Age                          inches)       population
                                         --------------------     per
                                            Dwarf     Other    enclosure
------------------------------------------------------------------------
Weaning to 5 wks........................       5.0      10.0          20
5 to 10 wks.............................       7.5      12.5          16
10 wks. or more.........................         9      15.0          13
------------------------------------------------------------------------

    (c) Space requirements for primary enclosures acquired on or after 
August 15, 1990--(1) Guinea pigs. (i) Primary enclosures shall be 
constructed and maintained so as to provide sufficient space for each 
guinea pig contained therein to make normal postural adjustments with 
adequte freedom of movement.
    (ii) The interior height of any primary enclosure used to confine 
guinea pigs shall be at least 7 inches (17.78 cm).
    (iii) Each guinea pig shall be provided a minimum amount of floor 
space in any primary enclosure as follows:

[[Page 63]]



------------------------------------------------------------------------
                                                           Minimum floor
                                                               space
               Weight or stage of maturity               ---------------
                                                          in\2\   cm\2\
------------------------------------------------------------------------
Weaning to 350 grams....................................     60   387.12
350 grams....................................    101   651.65
Nursing females with their litters......................    101   651.65
------------------------------------------------------------------------

    (2) Hamsters. (i) Primary enclosures shall be constructed and 
maintained so as to provide sufficient space for each hamster contained 
therein to make normal postural adjustments with adequate freedom of 
movement.
    (ii) The interior height of any primary enclosure used to confine 
hamsters shall be at least 6 inches (15.24 cm).
    (iii) Except as provided in paragraph (c)(2)(iv) of this section, 
each hamster shall be provided a minimum amount of floor space in any 
primary enclosure as follows:

------------------------------------------------------------------------
                        Weight                            Minimum floor
-------------------------------------------------------     space per
                                                             hamster
           g                          ozs              -----------------
                                                         in\2\    cm\2\
------------------------------------------------------------------------
<60                     <2.1                                 10    64.52
60 to 80                2.1-2.8                              13    83.88
80 to 100               2.8-3.5                              16   103.23
100          3.5                       19   122.59
------------------------------------------------------------------------

    (iv) A nursing female hamster, together with her litter, shall be 
housed in a primary enclosure that contains no other hamsters and that 
provides at least 121 square inches of floor space: Provided, however, 
That in the case of nursing female dwarf hamsters such floor space shall 
be at least 25 square inches.
    (3) Innovative primary enclosures that do not precisely meet the 
space requirements of paragraph (c)(1) or (c)(2) of this section, but 
that do provide guinea pigs or hamsters with a sufficient volume of 
space and the opportunity to express species-typical behavior, may be 
used at research facilities when approved by the Institutional Animal 
Care and Use Committee, and by dealers and exhibitors when approved by 
the Administrator.

[32 FR 3273, Feb. 24, 1967, as amended at 55 FR 28882, July 16, 1990]

                  Animal Health and Husbandry Standards