Use of Wire-Bottom Caging for Rodent Housing

Proper housing is essential to animal wellbeing, to the quality of research data and to the health and safety of animal personnel. While it is true that rodents have historically been housed in cages with wire flooring suspended over a collection pan, studies have shown that rodents prefer solid-bottomed caging, with bedding, which allows for species-specific behavior such as nest-building.  Solid-bottomed caging, with bedding, is therefore the recommended housing method for rodents at UCI.Housing of rodents on wire mesh flooring  (including metabolic cages if applicable) must be fully described in the approved protocol and must include a justification for the exception to standard housing.  The protocol must also describe in detail how animals will be monitored for complications such as foot sores, peripheral nerve abnormalities and neuropathy associated with the wire-bottom caging, and address how these possible adverse effects will be managed.

Guidelines for Use of Wire-Bottomed Caging

  • Guinea pigs, chinchillas and rats weighing less than 500 grams and/or in residence less than 4 months may be housed on wire flooring.
  • Rodents with litters must have solid flooring with bedding.
  • Animal care and investigative staff observing clinical signs of discomfort or lesions related to wire flooring must immediately provide solid flooring with bedding.


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