The majority of the rooms in the ARC building are maintained under "conventional" conditions, meaning that there is no use of microisolator tops, HEPA changing stations, or autoclaving to ensure that animals remain "clean". A notable exception is the Mouse Genetic Engineering Facility, which is managed as a modified barrier by staff of the Institute for Cellular and Molecular Biology. Common lab-associated mouse viruses such as MPV and MHV are endemic in the conventional areas of the facility. 

In order to monitor the colony health status of the rodent colonies in the facility, the ARC employs a viral screening program using "sentinel" animals. Naive rodents from viral antibody free commercial sources are ordered and placed in all rodent rooms. ARC staff will place these sentinel animals in marked cages in rodent colony rooms, at a ratio of one sentinel cage per 40-60 colony cages. When cages are changed, a random sample of dirty bedding from investigator-owned cages in the room will be transferred to the assigned sentinel cage to increase the opportunity for sentinel animal exposure to any agents present in the room. On a semi-annual basis, blood samples are taken from the sentinel animals and serum is sent to an outside diagnostic lab for viral screening. Test results are posted on the animal room door when received, and the room is assigned  a status category based on what agents are present. A corresponding status hierarchy then determines the general room entry order, a strategy used to minimize cross-contamination from clean to contaminated areas. 

The cost of screening, including the purchase of sentinel animals, is shared by all researchers who have animals in the room. A complete panel of thirteen agents is screened for mice and ten for rats, at a cost of approximately $7.95 per agent. There is also a charge for collection and transport of samples when needed. Monitoring is performed on all rooms (including previously positive areas) in order to verify current status and to assure that excluded agents such as Sendai or LCMV are not present.



                (E) = Currently Excluded

  • Sendai - Mice & Rats (E)
  • Pneumonia Virus of Mice (PVM) - Mice & Rats (E)
  • Mouse Hepatitis Virus (MHV) - Mice
  • Mycoplasma pulmonis (M. PUL) - Mice & Rats (E)
  • Theiler's Virus (GD7) - Mice
  • Minute virus of mice (MVM) - Mice (E)
  • Reovirus 3 - Mice & Rats (E)
  • Mouse Adenovirus (MadV) - Mice (E)
  • Ectromelia virus - Mice (E)
  • Polyoma virus (POLY) - Mice (E)
  • Lymphocytic choriomeningitis (LCM) - Mice (E)
  • Epidemic diarrhea of infant mice virus (EDIM) - Mice (E)
  • Sialodacryoadenitis Virus of Rats (SDA) - Rats (E)
  • Toolan's H-1 virus (H-1) - Rats (E)
  • Killham Rat Virus (KRV) - Rats (E)
  • Parvovirus (MPV) - Mice; (RVP) - Rats
  • Hantavirus - Rats
  • Rat Minute Virus (RMV) - Rats

NOTE: When rodent shipments from noncommercial sources (e.g., another university) are requested, the ARC requires the facility of origin to provide colony health status documentation that is comparable to our monitoring.  

The ARC will work with individual laboratories to provide enhanced screening (e.g., quarterly testing, adding parasite or bacteria screening, etc.) upon PI request. Consultation on the potential negative impact of endemic viruses on particular research studies is also available, and potential response options such as depopulation, rederivation, or "burnout" can be considered when indicated. Groups with an interest in investing in enhanced colony operating procedures to increase the protection for their animals should contact the ARC Director to discuss the possibility of microisolator utilization or modified barrier housing.