What is a typical requirement when acquiring new mice from an external supplier?

• A. Quarantine and health assessment prior to integration; confirm health status and record.
• B. Immediately integrate into main housing to accelerate acclimation.
• C. Only quarantine if a disease is observed.
• D. Do not quarantine; new mice are assumed healthy.

Answer: (A)

Quarantine and a health assessment before adding new mice to the main colony is a protective step to prevent introducing problems from outside sources. Animals from external suppliers can carry pathogens, parasites, or other health issues that aren’t yet visible. By placing them in separate housing for a defined period and conducting a health check, you verify their health status, catch any problems early, and document the results before they share space with established mice. This period also allows observation of behavior and appearance and gives time to complete any required tests or screenings. The quarantine duration should be long enough to observe for signs of illness and complete screening, typically a few weeks, with policy-based adjustments. Immediate integration or waiting to quarantine only if disease appears increases risk to the colony, while proper quarantine minimizes cross-contamination and helps maintain overall colony health.