Effect of wheat germ zinc on growth in rats and mice: application for estimating relative availability of dietary zinc (1043.7)

Abstract

Zinc deficiency is one of the most important health problems in the world. Wheat germ contains relatively high amount of zinc and is a potential source of zinc. The aim of this study was to estimate the relative availability of wheat germ zinc based on the half‐maximum dose for the growth of animals. Experimental diets containing the graded levels of zinc from 0 to 18 mg/kg were prepared using zinc sulfate, untreated wheat germ and phytase‐treated wheat germ. The relationship between dietary zinc level and body weight gain was analyzed using the Hill equation to determine the half‐maximum dose of dietary zinc. Experimental diets were fed for 19 days to three‐week‐old male Wistar rats and for 7 days to three‐week‐old male ICR mice. Body weight gains were recorded. When the data of the rats were analyzed, the relative availability of untreated wheat germ zinc was 1.0 and that of phytase‐treated wheat germ zinc was 0.98 using zinc sulfate as a norm. When the mice data were analyzed, the relative availability of untreated wheat germ zinc was 1.0 and that of phytase‐treated wheat germ zinc was 1.1 using zinc sulfate as a norm. Availability of wheat germ zinc was similar to that of zinc sulfate. Wheat germ zinc may be available as zinc source. Partly supported by Japan Society for the Promotion of Science Grants‐in‐Aid for Scientific Research (C) (25350137).