hypothyroidism , defined as a serum concentration of less than 70 ng of triiodothyronine ( t3 ) /dl or less than 1.5 microgram of thyroxine ( t4 ) /dl , or both , was diagnosed in 108 dogs by means of radioimmunoassay techniques .
C0020676
hypothyroidism
C0041014
triiodothyronine