Colony Health Monitoring Program

The primary objective of the Colony Health Monitoring (CHM) Program is to monitor mice and rat colonies for the presence of agents that would compromise the "Specific Pathogen Free" (SPF) status so that appropriate management steps can be taken should they be found. Ferrets are monitored semi-annually. For more information on the ferret CHM process, please contact us directly.

Rodent Colony Health monitoring & Maintenance

Background

Emory University has been continuously accredited by AAALAC international since 1992. Rodents entering into colonies maintained at Emory University Division of Animal Resources DAR may originate from one of three sources: 

1. Emory DAR's List of Approved Vendors
2. DAR Rodent Quarantine Program
3. Mouse Transgenic and Gene Targeting Core (TMF)

Rodents are verified to be free from a defined set of adventitious pathogens upon entry into a colony, and policies are in place to help maintain this ‘Specific Pathogen Free’ (SPF) status. The primary objective of the health monitoring program is to monitor colonies for the presence of agents that would compromise the SPF status so that appropriate management steps can be taken should they be found. 

General Husbandry Practices for Rodents in DAR

Rodent housing rooms, except under special conditions, are under negative relative air pressure with respect to adjacent corridors. Personnel entering rodent rooms must wear dedicated gowns and gloves when handling rodents and use a DAR approved disinfectant in the animal facility.Colony animal cage bottoms are changed out weekly on static microisolator cages and every two weeks on ventilated cage systems. Corncob bedding and a cotton fiber nest material are the default for most mouse strains, with exceptions for specific strains or based on IACUC protocol requirements. Rodents are fed irradiated diets and water sanitation varies depending on the building. Water bottles, if present, are replaced weekly and food is added during each cage change. Wire bar lids and food hoppers are replaced when visibly soiled, when a cage is depopulated, or at least every 6 months. Sterile housing is available for mice which includes an autoclaved water bottle and a complete autoclaved cage change weekly. 
 
Rats may be housed in solid bottom cages without filter tops, in static filter top cages, in ventilated caging systems, or in suspended stainless-steel cages. Cages, food, water and bedding for immunocompetent rats typically are not autoclaved prior to use, but cages are sanitized at 180°F.  

Rodent Colony Health Reports

A customized rodent colony health report can be requested online through DAR Quality Assurance and Diagnostic Laboratory here:Emory Rodent Colony Health History Request. Requested reports will be provided to the requestor within two business days, excluding weekends and holidays.  

Biological Materials Screening Policy

All biological materials administered to rodents in Emory colonies must be screened for adventitious pathogens in accordance with DAR policy, which can be viewed here: Biological Materials Screening Policy

Rodent Colony Health Surveillance Program Overview

Since 2021 Emory has relied on environmental/sentinel-free soiled bedding samples for health monitoring in DAR rodent colonies, compared to the previous method that utilized live animals. One to two empty, sanitized, and autoclaved colony health collection cages are placed into each populated room to monitor animals of the same health status (e.g., Sterile or Non-Sterile). 

During each cage change session, approximately one tablespoon of soiled bedding is collected from each cage being changed and transferred into the colony health monitoring (CHM) cage. Only bedding from cages of the same health status should be combined into the CHM collection cage.  

Bedding transfers continue for the duration of the monitoring period: 

• High-level SPF facilities: 3 months (90 days; quarterly) 
• Conventional SPF housing: 4 months (120 days; triannual) 

At the end of a monitoring period, colony health monitoring cages are then collected from their housing rooms and are replaced with a new cage for continued monitoring. Collected colony monitoring cages are then processed for testing by collecting PathogenBinder® (Charles River Laboratories) media. These samples are submitted at the room and health status level accordingly and submitted to third-party commercial laboratories for PCR diagnostic analysis. Conventional SPF housing locations are minimally tested for the agents and at the frequency shown in Tables 1 and 4 (mice, and rats, respectively). The additional agents monitored, and frequency tested in high-level SPF and high-level sterile SPF rooms are shown in Tables 2 and 3. Note that some buildings have specialized rooms that necessitate testing in addition to that shown in the tables, and health reports for those rooms will indicate any additional agents monitored. Please request a health report for further details. 

Table 1. Agents monitored in conventional SPF mouse housing. 

Table 2. Status for high-level SPF mouse housing: Status same as listed in Table 1 unless specified below. 

Table 3. Status for high-level SPF Sterile mouse housing: Status same as listed in Tables 1&2 unless specified below. 

Table 4. Agents monitored in conventional SPF rat housing. 

   
Notes: 

MNV is assumed to be endemic in the general population 

*C. Bovis, Pneumocystis spp., and Rat polyoma virus 2 (RatPyV2) are monitored in sterile populations. 

*Mycoplasma pulmonis (MPUL), Lactic Dehydrogenase Elevating Virus (LDV), Lymphocytic Choriomeningitis (LCMV), Polyoma Virus (POLY), and Mouse cytomegalovirus (MCMV) are monitored annually in conventional SPF mouse rooms except for B-Clinic where these are monitored triannually.  
 

Definitions: 

Excluded: Actions are taken if a positive result is found. Actions include researcher notification, room quarantine and additional testing of colony animals to confirm the positive and its source. The specific processes depend on the agent and circumstance. 

Monitored: No definitive action is taken if a positive is noted. 

Varies: Agent is either excluded or monitored based on the status of the room. 

Dependent: Agents is either monitored annually or triannually based on location.  

Updated: 8/25/2025