Hypothyroidism is one of the most common endocrine disorders in dogs and profoundly affects quality of life when undiagnosed or inadequately managed.
Hypothyroidism causes significant welfare impairment across multiple dimensions simultaneously. Affected dogs experience fatigue that limits their capacity for play and exercise, skin conditions that may cause chronic discomfort, weight gain that stresses joints, and in some cases neurological effects including peripheral neuropathy. Because the onset is gradual, owners often attribute changes to normal ageing, delaying diagnosis. The welfare impact of timely diagnosis and treatment is substantial: most dogs experience dramatic improvements in energy, coat condition, and overall demeanour within weeks. The treatment itself is straightforward and inexpensive, meaning the main welfare challenge is ensuring diagnosis rather than accessing therapy. Breed-specific awareness and routine screening of at-risk breeds could prevent significant unnecessary suffering.