Animal Use on the UIUC Campus
Policies Pertaining to the Care and Use
of Animals in Research and Teaching



Use of Wire-Bottom Caging for Rodents

Reference(s):

  • Guide for the Care and Use of Laboratory Animals (Guide), NRC, 1996

Background:

Acceptable primary enclosures for animals must, among other things, allow for the normal physiologic and behavioral needs of the animals, including urination and defecation, maintenance of body temperature, normal movement and postural adjustments, and, where indicated, reproduction. Rodents are often housed on wire flooring, which enhances sanitation of the cage by enabling urine and feces to pass through to a collection tray. However, evidence indicates that solid-bottom caging with bedding is preferred by rodents. Furthermore, clinical abnormalities associated with housing rodents on wire-bottom caging have been documented. Solid-bottom caging with bedding is therefore recommended for rodents.

Policy:

Wire-bottom caging for rodents is permissible only when a) there is an appropriate scientific rationale for not using solid-bottom caging with bedding, or b) when suitable solid-bottom caging and bedding is not available.

  1. Role of the Investigator:    If principal investigators desire to house rodents in wire-bottom caging, they must submit in writing an acceptable scientific rationale for using wire-bottom instead of solid-bottom caging with bedding.

  2. Role of the Department/College Animal Care Unit:    The college/departmental animal care unit is responsible for maintaining an inventory of solid bottom cages adequate to meet the needs of the rodent populations. In cases where animals must be housed in wire-bottom cages because of shortages of solid-bottom cages, the ACU or facility administration will be required to submit to the ACUC a plan for addressing the shortage.

  3. Institutional Animal Care and Use Committee (IACUC) Oversight:    The IACUC will review all requests to house rodents in wire-bottom caging and plans for addressing caging shortages. The IACUC also will monitor animal facilities to verify compliance with this policy.