This is when there is a lowered production and release of the the T3 and T4 hormones. The T3 (liothyronine) and T4 (levothyroxine) hormones are required for a normal metabolism in the body.
It is primarily caused by the result of lymphocytic thyroiditis or idiopathic atrophy of the thyroid gland. Other causes can be cancer or congenital defects.
Treatments
Vet may prescribe an oral replacement hormone, treatment will be lifelong.
This condition is common in the following Dogs & Cats