Abstract
Plasma levels of thyroxine (T4), total proteins, albumin and transthyretin (T4-binding prealbumin) were determined in chick embryos at 19 days of incubation. There were significant sex differences (P<0.05) in plasma levels of T4 and total proteins. A highly significant positive correlation between plasma levels of T4 and albumin (r=0.55, P<0.001, n=42) was found; this suggests that plasma albumin level may be a useful parameter to evaluate thyroid function in the chick embryo. Moreover it was confirmed that both albumin and transthyretin were major T4-binding proteins in chick embryos as well as in growing chickens.
