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new returning rats quarantine time frame the absolute minimum quarantining for bringing rats in is 14 days this covers the acquisition of new rats or the return of resident rats to the colony after exposure to other rats shows co breeding returned placements etc
If you add a gerbil later, you would have to do a 2-3 week quarantine (different airspace) to avoid transmitting contagious diseases. Once you are sure that all gerbils are healthy, you can start with a slow introduction (about 15 minutes per day or so) on neutral territory (like the bath tub).