Zinc deprivation and zinc repletion: effect on the response of rats to infection with Strongyloides ratti.

The course of a subcutaneous weight-related infection with Strongyloides ratti was followed in rats fed diets containing either 3 mg Zn/kg diet [zinc deficient (Zn-)] or 40 mg Zn/kg diet [zinc adequate (Zn+)]. At 19 d postinfection (dpi) the proportions of larvae persisting in the intestines as adult worms were 52 +/- 2% (means +/- SEM) for Zn-, 39.5 +/- 2.5% for pair-fed Zn- (Zn-PF), and 31.6 +/- 3.2% for Zn+ (p less than 0.001, analysis of variance); some Zn- rats were then transferred to the zinc-adequate diet [This was the zinc-repleted group (ZnR).] Both groups retained a group of pair-fed controls (Zn-PF and ZnRPF). Between 19 and 28 dpi ZnR animals gained weight faster than did Zn- animals and had heavier thymuses relative to body weight. Zinc deficiency enhances the establishment of S ratti larvae in the intestine of rats and alters the characteristics of intestinal expulsion of the nematodes; however, spontaneous cure was achieved by 38 dpi in both Zn- and control groups.