The Effects of Dietary Cadmium, Zinc, Iron and Copper Concentrations of Tissues and Hair in Rats

Lee, Keun-woo; Lee, Hyun-beom

Korean Journal of Veterinary Research 1987;27(2):361-383.

Keun-woo Lee, Hyun-beom Lee

Department of Veterinary Medicine, College of Agriculture, Kyungpook National University

사료내 카드뮴 첨가가 체조직과 피모의 카드뮴, 아연, 철 및 구리함량에 미치는 영향

이근우, 이현범

경북대학교 농과대학 수의학과

Abstract

This thesis was designed to find out whether the cadmium content of hair in living animals reflects the status of cadmium accumulation in internal organs or muscles so that this status can be used as a diagnostic method. Forty-five rats were divided into 4 experimental groups and one control group. The control group received a basal diet which contained zinc $100{mu}g/g$, iron $80{mu}g/g$ and copper $135{mu}g/g$. The experimental group received experimental diets sllpplemented with 1, 10, 100 or $1,000{mu}g/g$ cadmium as cadmium sulfate. Rats were dissected on the 28th or 56th day of experimental periods and tissues, blood and hair samples were taken, dried and burned to ash and analysed. The cadmium, iron zinc and copper concentrations were measured with an atomic absorption spectrophotometer. In addition feed efficiency and hematological changes were observed. The results obtained can be summerized as follows: A marked decrease in feed intake, weight gain and feed efficiency were observed from 1 or 2 weeks of experimental periods, which was in accordance with the dosage and periods. The cadmium contents of kidney, liver, spleen and muscle were significantly increased in all experimental rats; the accumulation was marked in kidney and liver tissues. It was shown that the cadmium contents of hair reflects the cadmium accumulation in internal organs and muscle; the higher the cadmium levels of diet and of rat tissues, the higher the cadmium content of hair. In the $100{mu}g/g$ group of rats erythrocyte counts and. hemoglobin concentrations were decreased. A significant(p<0.01, p<0.05) increase in iron contents of kidney, liver and muscle was observed in 10, 100, $1,000{mu}g/g$ groups of rats on the 28th day of experiment. A significant (p<0.01, p<0.05) increase in zinc contents of kidney, liver and muscle was observed in all experimental rats. On the other hand, serum zinc concentration was decreased. A significant(p<0.01) increase in copper contents in the liver was observed on the 28th day in $100{mu}g/g$ and $1,000{mu}g/g$ groups of rats. From these results it may be concluded that the analysis of hair for cadmium is a useful diagnostic approach for the cadmium status of internal organs and muscle in living animals.