What it is
When a blood vessel is damaged, a chain of clotting proteins switches on one after another to build a firm plug. Hemophilia A breaks one link in that chain, a protein called factor eight. Without it a first, loose plug still forms but is never properly reinforced, so bleeding may seem to stop and then start again, or blood seeps quietly into joints and muscles.
The gene sits on the X chromosome, so the disease shows up mainly in males, while females can carry it without any signs and pass it on. The first clues may appear in puppyhood, when teething or a vaccination leaves a bleed that lasts too long.
Day to day, life with such a dog is about avoiding knocks: calm games instead of rough wrestling, no stick-chasing, and telling every vet, groomer and trainer about the condition before they handle the dog.
Signs you may notice
- Large bruises from small knocks
- Swollen, painful joint
- Limps for no clear reason
- Small cuts bleed for long
- Bleeding gums while teething
You may notice a dog that bruises easily with large bruises or swellings, limps for no clear reason, or bleeds for a long time from a small cut or from where a puppy tooth has fallen out. If bleeding will not stop, don't wait: take the dog to a vet right away.
When to see a vet
Bleeding that will not stop, or sudden weakness with pale gums, means a vet is needed immediately. Book a visit if your dog bruises easily or limps without a clear reason.
This is general information, not veterinary advice. For your own dog's health, tests and treatment, see a vet.