Zinc deficiency during the latter third of pregnancy: effects on fetal rat brain, liver, and placenta.

The effects of zinc deficiency during the last third of gestation on the growth and development of the fetal rat at term were investigated. Zinc deficiency resulted in anorexia and weight loss of the pregnant dams. Fetuses from such dams displayed intrauterine growth retardation when compared with fetuses from pair-fed or ad libitum-fed controls given adequate zinc. Although the brains of the zinc-deficient fetuses were smaller than those of the controls, the brain was relatively spared while the liver was severely affected. The total cell number was reduced and there was an apparent increase in cell size in the brains of zinc-deficient fetuses in comparison with the brains of the controls. The growth failure of the zinc-deficient liver resulted in a smaller complement of total DNA, RNA, protein, and lipid, and there was less incorporation of [3H]thymidine into DNA in the liver. The placenta appeared to be only marginally affected by the zinc deficiency.