Hypothyroidism in Dogs

Category
Hormonal
Breeds documented
91
Published sources
23

Overview

The thyroid glands in the neck make hormones that help control how the body uses energy. When too little thyroid hormone is available, many body functions slow down. In the most common form, thyroid tissue is damaged by the immune system or replaced by other tissue. This can cause changes in energy, body weight, skin, and coat.

Signs to watch for

  • Less energy or less interest in activity
  • Weight gain despite eating no more than usual
  • Seeking warmth or struggling in the cold
  • Thinning hair or bald patches without much itching
  • Dry, brittle fur or slow regrowth after clipping
  • Repeated skin or ear infections

Usually develops in adulthood, most often in middle age.

When to get help Book a vet visit if unexplained weight gain, low energy, or coat changes appear.

Diagnosis and tests

Vets assess the signs, perform an examination, and use blood tests to check thyroid function. A low thyroid hormone level alone cannot confirm hypothyroidism, because other illnesses and some medicines can lower it. The Orthopedic Foundation for Animals (OFA) offers blood screening for inherited thyroid inflammation in breeding dogs. Repeat screening is needed because a normal result does not rule out thyroid disease developing later.

Breeds with documented risk

91 breeds

By breed size
  • 4 Toy
  • 16 Small
  • 33 Medium
  • 30 Large
  • 8 Giant

Most popular breeds on this list

All 91 breeds, A to Z

Inheritance

  • Autosomal recessive

    Toy Fox Terrier, Rat Terrier, Tenterfield Terrier, Spanish Water Dog, French Bulldog

    A dog is affected only if it inherits two copies of the gene variant, one from each parent. A dog with one copy is a carrier: usually healthy, but able to pass the variant on. When two carriers are bred, on average one puppy in four is affected. A DNA test can tell clear, carrier and at-risk dogs apart.

    As stated by OMIA

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.

Sources

  1. OMIA: Hypothyroidism, primary: omia.org
  2. Cornell Riney Canine Health Center: Hypothyroidism: vet.cornell.edu
  3. merckvetmanual.com
  4. merckvetmanual.com
  5. pmc.ncbi.nlm.nih.gov
  6. vetmed.tamu.edu
  7. ofa.org
  8. Afghan Hound: spl.cde.state.co.us
  9. Airedale Terrier: pubmed.ncbi.nlm.nih.gov
  10. Akita Inu: d-nb.info
  11. Borzoi: open.lib.umn.edu
  12. Cocker Spaniel: pmc.ncbi.nlm.nih.gov
  13. Goberian: petmd.com
  14. Hovawart: pmc.ncbi.nlm.nih.gov
  15. Hovawart: pubmed.ncbi.nlm.nih.gov
  16. Irish Doodle: petmd.com
  17. Lapponian Herder: kennelliitto.fi
  18. Russian Hound: ajokoirajarjesto.fi
  19. Slovak Cuvac: bin.yhdistysavain.fi
  20. Small Munsterlander: link.springer.com
  21. Swiss Hound: nkk.no
  22. Thai Bangkaew: he01.tci-thaijo.org
  23. Yorkiepoo: petmd.com