Entry of
A collie beside the yarn basket, and the medication note worth keeping
Herding dogs belong naturally in a wool household. What a collie needs from a knitting family is one written page: the list of medicines its MDR1 status makes risky.
People who keep yarn often keep herding dogs; the two go together like gauge and swatches. A collie can doze beside the basket for years without any trouble at all. What the household owes the dog is one written note: which common medicines its genes can turn risky, and who must be told before anyone prescribes, boards or treats. For the working list, the molecules to avoid, the neurological signs that mean an emergency and how the genetic test itself is run, the reference we keep pinned is the veterinary site devoted to MDR1 drug sensitivity in dogs. It reads the way a good pattern reads: the mechanism first, then the list, then what to do.
Which herding breeds carry the MDR1 mutation?
Collies, Australian shepherds, Shetland sheepdogs, border collies, old English sheepdogs, longhaired whippets and their crosses can all carry the MDR1 mutation, sometimes called ABCB1. The mutation weakens the barrier that keeps certain drugs out of the brain, so a dose that is ordinary for a Labrador can reach the nervous system of a sensitive collie.
Ivermectin is the famous example, and the one the mutation is named after in most households, but it is not alone. Loperamide, some sedatives and several chemotherapy drugs sit on the same list.
How do you test a dog and write the result down?
You test with a cheek swab or a blood sample sent to a veterinary laboratory, and the answer comes back as clear, carrier or affected. A clear dog can take the listed drugs normally. A carrier needs caution. An affected dog needs the list kept where anyone in the house can find it without asking.
Write the result in the household notebook, next to the dye-lot numbers and the needle sizes, because the discipline is the same one a knitter already has. Note the date of the test, the laboratory and the exact result in words, not just a tick. Then copy the page: one for the vet file, one for the boarding kennel, one folded into the glove box of the car. A note that stays in a drawer protects nobody.
What changes around the basket itself?
Very little, and all of it cheap. Keep the pill organizer on a high shelf rather than a low table, because a dropped worming tablet is a dog treat the moment it hits the floor. Count capsules when you open a bottle, the way you count stitches after a decrease row. And never let the knitting bag double as a medicine bag: a tablet loose among the stitch markers is a risk and a muddle at once.
If the collie is also grey at the muzzle, the questions widen into weight, ramps and evening stiffness, which we wrote down in the entry on an old dog beside the knitting chair. And because a sensitive dog and loose fibre should never meet unsupervised, the storage rules in leftover yarn and pets apply to this household twice over.
Sources
For the MDR1 test itself, the laboratory that runs it for much of North America is the Veterinary Clinical Pharmacology Laboratory at Washington State University: vcpl.vetmed.wsu.edu.