Rodent Housing Policy
Boston University Animal Science Center (ASC) maintains centralized vivaria and resources for their optimal maintenance and use, to support animal research at BU. ASC not only provides daily care and veterinary oversight to our animals but also develops policies consistent with our animal welfare regulatory requirements at federal, state and local levels. As our vivaria constitute a university-wide shared resource, their management with respect to the housing space allocation, equipment use, biosecurity and operational oversight must be closely monitored by ASC staff. Inefficient use of these shared resources will ultimately result in higher costs for our services and increased per diem rates to the faculty. It should be noted that breeding efficiency and fecundity in mice are more often related to the strain than the daytime traffic through the area since rodents normally breed during the dark cycle.
Cage-Level Occupancy for Mice and Rats
- Mice and rats should be group housed whenever possible. Individual housing may occur for study reasons, fighting, attrition, or if only one male is weaned in a litter.
- Most mouse cages will accommodate up to 5 adults of one sex, a breeding pair or harem, or two adults and a litter.1,2
- For rats, 1-2 adults or a female with litter can be accommodated depending on the weight of the adult animals.
- Male mice from different litters or from the same litter but separated for an extended period of time should not be recombined to avoid injuries related to fighting.3
Vivarium Space Utilization for Mice and Rats
- Room- and vivarium-level housing are determined by the specific research needs and overall occupancy of the facility.
- Rooms are assigned based on husbandry and research needs, such as ABSL-2 husbandry, chemical hazard handling, light cycle, and animal movement to and from the lab.
- Housing equipment and rooms are not dedicated to individual PIs. Proximity and access to vivarium from the lab may be considered and accommodated whenever possible.
- New housing rooms will not be opened unless existing rooms are at capacity, except when housing exceptions require it (e.g. reverse light).
- Everyone must follow the posted room-entry order without exceptions.
- Use posted PPE by room or facility.4
- Sanitize shared equipment before and after their use. Supplies brought in and out of the vivarium should also be sanitized or sterilized appropriately, so that they do not become a source or act as carriers to spread the excluded agents.
- Cages should not be moved among racks within the same room or to different rooms without a formal transfer request. Moving cages will affect the specificity and accuracy of the colony surveillance results.
- Noncompliance with colony biosecurity guidelines increases the risk of introducing or spreading excluded pathogens that may cause disease outbreaks and interrupt critical research.5,6
ASC is committed to accommodating the needs of BU’s rodent users wherever possible. PIs may convey their preferences with justification but final decisions on the allocation of our shared resources will be made by ASC management.
1 HUS 48: Rodent Cage Change
2 HUS 56: Weaning Rodents
3 BU ASC Male Housing Policy
4 SAF 05: Personal Protective Equipment (PPE)
5 VET 46: Soiled Sentinel Program
6 VET 55: Rodent Quarantine Housing