Rodent Housing – Definitions and Exclusion lists


Office of Research, ULAR Guideline, Revised 06/14/2023

Rodent Housing 

All standard rodent diet is irradiated (sterile) and water is treated with reverse osmosis with the exception triple filtered water in Sisson Hall. Water is provided via an automatic water system primarily with water bottles being available as needed for health or experimental purposes.   

Type of Cage Ventilation and Per Diem Charges

Rodents are primarily housed in microisolator (MI) cages utilizing individually ventilated cage (IVC) systems with filtered air and active exhaust. Alternatively, rodents may be housed in a standard shoebox cage on a suspended rack or in a MI cage placed on a cart or tabletop. The later cages utilize static (passive) ventilation and require more frequent cage changes to maintain an appropriate microenvironment for the animals. The type of ventilation and cage requirements (autoclaving, paper bedding, or other enhanced environment) will determine the per diem charges that will apply to a cage.

Hazardous (chemical, biologic, and radioactive) cages require a 30% increase to the standard per diem to cover special handling procedures required by Environmental Health and Safety to protect the animals and personnel for hazards. View complete list of per diem rates and fees.

Levels of Rodent Housing



Barrier - Sterile (Level 1 and 2)

It is recommended that immunocompromised rodents, those with an unknown immune status and those undergoing whole body irradiation be housed in a sterile room.

Barrier - Non-Sterile (Level 3 and 4)

Conventional (#5) 

Mouse Agent In-house Screening List

All Mouse Rooms

Additional Room Level Restrictions

Additional Information

Contact the clinical veterinarian with any rodent housing questions.



Article ID: 106
Created: July 23, 2025
Last Updated: July 23, 2025

Online URL: https://ohiostateresearch.knowledgebase.co/article/rodent-housing-definitions-and-exclusion-lists-106.html