[Effect of marginal zinc deficiency on humoral immunity in rats].

The purpose of this experiment was to examine the effects of a marginal zinc deficiency on serum immunoglobulin (Ig) IgM and IgG1 levels. 60 weanling female Sprague-Dawley rats were divided into six groups of ten animals each. Two control groups (73.7 ppm Zn) and two zinc-deficient groups (4.3 ppm Zn) were fed a semisynthetic casein diet ad libitum. The animals of two further groups received the control diet (73.7 ppm Zn) pair-fed to the zinc-deficient animals. After 15 days the rats of one group of each treatment were infected i.m. with a single injection (0.2 ml) of a bovine enterovirus, apathogenous to rats. 3 weeks later, all rats were anesthetized with ether and decapitated. Infection of the rats with the bovine enterovirus had no effect on the serum immunoglobulin level. The marginal zinc deficiency did not alter the IgM and IgG1 serum concentrations at all either. It remains to be examined whether other Ig-classes will react to marginal zinc deficiency. Also, the effect of severe zinc deficiency on the humoral immune system must be studied.