Low zinc intake affects maintenance of pregnancy in guinea pigs

Zinc deficiency during pregnancy has severe effects in animals. To what extent the effects in animals apply to human pregnancy is not known. Because the pregnant guinea pig shares characteristics with pregnant women that make it a useful model, three experiments were done with guinea pigs in which Zn intake was reduced beginning on the 30th d of gestation. Reduced Zn intake in two of the three experiments resulted in abortion or premature delivery. Zinc-supplemented animals with feed intake restricted to that of Zn-deficient animals also aborted or delivered prematurely. Zinc-supplemented animals fed for ad libitum access delivered living young at term. Fetal/neonatal liver Zn concentration was low in the guinea pigs compared to that reported for other animals and was affected to a lesser extent by low Zn intake by the dam. Zinc concentration of neonatal plasma was also less than that in several other species. Change in activity of angiotensin-converting enzyme with addition of Zn in vitro was greater in the plasma of Zn-deficient guinea pigs than in that of Zn-adequate guinea pigs and may be useful as an indicator of Zn status.