Respiratory signs move through a group of mice while individual mice decline at different speeds, and a watch system has to track the individuals. Keep one log per mouse and record exactly five fields at a morning and an evening check: the mouse's name or marking description, its breathing sound and effort, any sneezing you heard during the check, the food and water it took, and its activity and posture since the last check. Identify cage mates by markings you can recognise at a glance, such as a patched coat or a nicked ear, and write that description at the head of the log so anyone covering a check records against the right mouse.
Run Each Timed Check the Same Way
Begin outside the enclosure, standing quietly for two minutes before you touch a door or a lid. In that stillness you can hear clicking, wheezing, or laboured breathing that handling noise would bury, and you can watch who sits hunched in a corner, who breathes with visible effort in the flanks, and who comes forward expecting food. Then open the enclosure, offer the usual feed, and watch who eats, who mouths food and drops the food, and who stays in the nest. Fill the five fields in the same order every time. A worked line follows those fields exactly: name or marking description; breathing sound and effort; sneezing heard during the check; food and water taken; activity and posture since the last check. Breathing that looks or sounds harder than at the previous check matters more than any single observation, which is why the order and the timing of the checks stay fixed.
Keep a spare log sheet clipped to the enclosure for any evening you are away, marked with the covering person's name, and no check then goes unrecorded while the usual keeper is out that night.
Keep the Air and the Routine Steady
Support the watch with steady housekeeping rather than experiments. Keep bedding low in dust, keep the enclosure ventilated, and keep scented sprays, smoke, and strong cleaning smells away from the room, as irritated airways cope badly with added irritation. Clean on the usual schedule instead of deep-cleaning daily, because constant upheaval stresses the group and stress muddies the activity field you are trying to read. Handle mice with signs after the bright cage mates, and wash your hands between groups kept in separate enclosures, and do not move mice between enclosures to even out numbers while signs are spreading. Add no new mouse to the group during a watch period, and keep any newcomer housed apart until a vet advises otherwise.
Share the Logs Early and in Full
Mice are small, and breathing problems in a mouse can worsen quickly, so the log travels to the vet early rather than after a week of watching. Phone a vet experienced with small mammals when any mouse breathes with effort, stops eating, sits hunched and still, or loses condition, and phone the same day when several mice develop signs together. Read the vet the run of entries for the mouse whose entries concern you, then summarise the rest of the group by name, so the clinic hears both the individual picture and the group pattern. Bring the logs to the appointment, and keep recording through any plan the vet sets, using the same five fields, so improvement or decline shows in the record rather than in your impression. Filed by mouse and date, these short logs give the clinic a colony history it could never reconstruct from memory, and Pet Passport with KinsLe keeps every mouse's page in one place.