Decrease and recovery of serum zinc and bone growth of rats with chronic ingestion of 25 ppm and 50 ppm cadmium

Weanling female Wistar rats ingested 25 ppm or 50 ppm cadmium (Cd) as CdCl2 in water for 330 days. Suppression of body weight gain was observed during the early stages of ingestion. The serum zinc (Zn) concentration from Cd-treated rats was significantly decreased in both groups at 35 days. Cd groups gradually exceeded the control group in body weight gain. At the 330th day of Cd ingestion decreased Zn concentration was observed in the fibula bone, though exchangable serum Zn had almost returned to normal. The decrease of calcium (Ca) and hydroxyproline in fibulae was small. The severe decrease in serum Zn concentration during growing stages did not have a suppressing effect on bone growth. The recovery of body weight gain could be partly explained by the smaller intake of Cd water in adults than in young.