Taking in a relative's collie for a fortnight is a kindness with a checklist attached. Food, walks and sleeping spot are obvious; the one that matters most is the one least often asked: which medicines this particular dog must never have.
Why do some collies react badly to common drugs?
A mutation in a gene called MDR1 leaves some herding breeds unable to pump certain drugs out of the brain. A dose that is routine for a labrador can be dangerous for a collie, sheltie or Australian shepherd carrying two copies. The volunteer-run site on collie drug reactions keeps the Washington State University list of problem medicines and explains which breeds carry the mutation beyond the collies.
A saliva test answers the question once, for life. Many breeders and rescues now test before a dog changes hands.
What should a dog-sitter ask before the owner leaves?
Three things: the vet's number, the dog's MDR1 status if it is a herding breed, and a written list of anything the dog takes or must not take. Add the owner's permission to authorise treatment, and the risk of a bad weekend shrinks to nearly nothing.
The same care applies in reverse: if your own dog goes to a sitter, write the list down rather than leaving it to memory.
Does the extra walking help the sitter too?
Usually, yes. A borrowed collie walks more miles than most guest walkers planned, and a fortnight of twice-daily outings is a reasonable reset for a stiff back. Pace the first days rather than matching the dog's enthusiasm.
When does a symptom mean the vet, not a wait?
Tremors, disorientation, excessive salivation or a dog that cannot walk straight after any medication mean the vet, now. Do not wait to see whether it passes.
For the exercise side of the same arrangement, see our guide to keeping a shepherd breed fit.
Sources
For the drug list itself, see the WSU veterinary clinical pharmacology page on problem drugs.