Abstract
The diagnostic value of Total T4 (TT4) levels was reconsidered in dogs with skin disorders. TT4 (CLEIA, Mitsubishi Chemical Medience Corporation, Animal Laboratory Center) was evaluated in 161 dogs requiring examination for hypothyroidism and in 7 clinically healthy dogs. In dogs with hypothyroidism, TT4 was 0.2 ± 0.6 μg/dl, which was apparently lower than the normal range (0.5-2.8 μg/dl), was less than the lowest mean TT4, 1.3 μg/dl, in dogs with various skin diseases besides hypothyroidism. Based on these findings, it was suggested that TT4 levels were consistently low in dogs with hypothyroidism, and useful as a screening test if mean TT4 in dogs without hypothyroidism was used for the reference value.
