BY DR NICKY THOMAS, WYNNUM MANLY VETERINARY HOSPITAL
What is hypothyroidism?
Hypothyroidism is a hormonal deficiency in which there is a reduction in the production of thyroid hormone by the thyroid glands. The condition may be congenital but is more commonly seen in middle aged to old dogs. A number of breeds have been recognised as being more likely to develop hypothyroidism – Doberman Pinschers, Tibetan Terriers and Boxers were more commonly affected according to a retrospective study of cases in the UK.
Clinical signs
The clinical signs of hypothyroidism include:
- Animals may be easily fatigued and sleep more
- Dull attitude
- Seeking warmth
- Slow heart rate
- Weight gain without diet change
- Coat may become sparse, dry and lose shine; clipped fur may not regrow
- The skin may become hyperpigmented (darker)
- Animals may be prone to skin infections and show slow wound healing
Diagnosis
Diagnosis of hypothyroidism is based on clinical signs and blood tests. Your vet may perform any or all of a T4 level, free T4 or TSH (thyroid stimulating hormone) test. Affected dogs often have an increased circulating cholesterol level.
Treatment
Treatment of hypothyroidism requires ongoing/lifelong supplementation of thyroid hormone, usually in tablet form. Owners often notice an improvement in their dog’s demeanour very rapidly, but skin and coat improvement may take months.
Ongoing monitoring with regular blood tests is required to ensure your dog’s thyroid hormone level remains in the normal range.
