Haemophilia A – Border Collie

Haemophilia A is a hereditary bleeding disorder caused by mutations in the F8 gene, which encodes coagulation factor VIII—an essential protein required for normal blood clotting. In affected dogs, factor VIII is either severely reduced in amount or non‑functional, meaning the blood cannot clot properly. This results in a strong tendency for prolonged or spontaneous bleeding. In the Border Collie, the condition is inherited in an X‑linked recessive manner, so male dogs are typically affected while females are usually carriers.

Clinical signs generally begin within the first months of life, when puppies start normal play, teething, or experience minor injuries. Common signs include prolonged bleeding after small wounds, excessive bleeding following routine procedures (such as vaccinations), spontaneous bruising, nosebleeds, and bleeding into joints or muscles, which may cause lameness, swelling, or pain. More severe cases can develop internal bleeding, weakness, pale gums, or anemia due to chronic blood loss. The severity of symptoms can vary widely, but uncontrolled bleeding episodes can significantly affect health, mobility, and overall quality of life.

Haemophilia A is a serious condition. While some dogs can be managed with careful monitoring and supportive care, severe or recurrent bleeding episodes may become life‑threatening. In cases where bleeding cannot be controlled or quality of life declines significantly, euthanasia may be considered the most humane option.

Pubmed ID: 38104983

Year published: 2023

Omia ID: 437

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