ACUP ULAR Guideline

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

  • Personnel entering the room must wear personnel protective equipment (PPE) as indicated on the room entry sign. 
  • Personnel must move from most restricted (#1) to the least restricted health status (#5) as noted on the room door. Personnel should never move backwards in the entry order.
  • Cage transfers from a least restricted area to a more restricted area may require additional testing prior to movement.

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.

  • cages and bedding are autoclaved
  • cages must only be opened within the Biosafety cabinet (BSC)
    • animal manipulations including but not limited to cage changes must be performed within a BSC
  • either ventilated sterile or static sterile per diem rates will apply to cages at this level

Barrier - Non-Sterile (Level 3 and 4)

  • supplies are clean but not autoclaved
  • cages can only be opened within the BSC
    • animal manipulations including but not limited to cage changes must be performed within a BSC
  • either ventilated or static per diem rates will apply to cages at this level

Conventional (#5) 

  • supplies are clean but not autoclaved
  • cage manipulations occur on the tabletop

Mouse Agent In-house Screening List

All Mouse Rooms

  • Aspicularis tetraptera
  • Citrobacter freundii 4280/ C. rodentium
  • Ectromelia
  • Lymphocytic Choriomeningitis (LCMV)
  • Mouse Adenovirus 1 and 2
  • Mouse Hepatitis Virus (MHV)
  • Mouse Parvovirus (MPV,MVM, NS1)
  • Mouse Rotavirus (EDIM)
  • Mycoplasma pulmonis (MPUL)
  • Myobia musculi
  • Myocoptes musculinus
  • Pneumonia Virus of Mice (PVM)
  • Radfordia spp.
  • Reovirus 3
  • Sendai
  • Syphacia spp.
  • Theilovirus (MEV/GDVII)

Additional Room Level Restrictions

  • Level 1A - Corynebacterium bovis
  • Level 1 and 2 - Pneumocystis murina
  • Level 1 and 3 - Helicobacter hepaticus and Helicobacter bilis

Additional Information

Contact the clinical veterinarian with any rodent housing questions.