Aust Vet Practit, 1993. 23(1): p.2-6.
Feline hyperthyroidism is caused by the overproduction and secretion of thyroid hormones, thyroxine (T4) and tri-iodothyronine (T3) (Bond, 1986; Feldman & Nelson, 1987). It is a disorder affecting mainly middle-aged and old cats. The best indicator of hyperthyroidism may be weight loss in the face of polyphagia and hyper excitability (Feldman & Nelson, 1987; Labuc & Jones, 1988; Watson es al., 1981) In cats, this disease is most frequently due to functional multi nodular adenomatous hyperplasia or thyroid adenoma (Feldman & Nelson, 1987; Labuc & Jones, 1988). Functional thyroid carcinoma is rare, constituting 1% to 2% cases (Turrel et al., 1988).