[Effect of the thyroid in the development of intestinal hydroxylases].

The authors studied the saccharidase levels in the intestines of rats during the perinatal period. Sucrase and maltase values increase with advancing time, while lactase values decrease also age-dependently. The thyroid gland has a decisive role in the intestinal maturation of fats. In an assessment of circulating blood thyroxin levels, the authors found that the amount of thyroxin at birth is practically undetectable (less than 0,05 mug/100 ml expressed in iodine), rapidly increasing up to adult levels (3,8 mug/100 ml) 22 days after birth.