The short answer: no vaccine card exists for a mouse
A fancy mouse usually needs no vaccination proof for boarding, for the simple reason that pet mice are not vaccinated — there is no routine vaccine schedule for them. What a boarder asks for instead is paperwork of a different kind: a signed health declaration, details of his cage companions, your vet's contact information, an emergency contact who can make decisions, and written consent for the facility to arrange veterinary treatment if he becomes unwell while you are away. Because mouse boarding is uncommon, confirming a facility even accepts mice is the true first step.
Finding a boarder is part of the paperwork problem
Many boarding establishments that happily take rabbits and guinea pigs do not board mice at all, and those that do usually sit within exotic-pet or home-boarder services rather than large kennels. That scarcity shapes the paperwork: smaller exotic boarders often work from their own one-page intake form rather than a standardised system, so what one asks for will not match the next. Ask early what their form covers, whether they want it returned before the stay, and whether they house mice only in their own enclosures — most will insist your fancy mouse arrives in his own cage, which conveniently means his paperwork can travel taped to it. Get their requirements in writing, because a mouse is a short-notice problem if a booking falls through over a missing form.
The health declaration for a mouse
For a fancy mouse, the health declaration carries the weight a vaccine card carries for a rabbit. Expect to confirm that he is breathing quietly with no clicking or wheezing, that his eyes are bright without discharge, that his coat has no bald patches or scabs, and that he is eating, drinking, and active at his usual level. Respiratory signs deserve particular honesty in mice, who are prone to breathing problems and share airspace with other small guests at a boarder's. Note any recent changes — a new lump, weight loss you have noticed when handling him, or a course of treatment your vet has him on — and let the facility judge. A boarder who trusts your declaration will move mice whose health shifts during a stay to a quiet isolation cage quickly, which protects his cage mates too.
Companions, consent, and contacts
Mice are social, and the paperwork should say exactly who boards together: name his cage companions on the form, note if the group is female or a neutered male grouping, and flag any scuffles the staff should watch for, because a week in a new-smelling cage can unsettle a mouse colony's hierarchy. The consent section authorises the boarder to take him to a vet and approve necessary care with costs to you, and it should name a vet who will actually see a mouse — worth arranging in advance, since not every practice treats animals this small. Add your mobile number and a backup contact who knows the mice and can decide fast if you are out of reach.
What to hand over on the day
Arrive with the signed declaration, the boarder's intake form, your consent and contacts sheet, and a half-page care summary: his seed-and-grain mix, the fresh extras he knows, his wheel and nesting habits, and the instruction that deep cage cleans mid-stay are usually unnecessary and stressful. A mouse's world is scent-based, and staff who understand that will spot-clean around his nest rather than scrubbing away the colony's smell. Handled this way, drop-off takes minutes and your fancy mouse settles into a cage that still smells like home.
Keeping your fancy mouse's declaration, companion list, and consent forms stored in KinsLe's Pet Passport turns a scattered set of small-pet forms into one portable packet you can hand to any exotic boarder.