Dietary Selenium and Cadimium Interrelationships in Growing Swine

Publisher Website
Google Scholar
Abstract
In a 6-week experiment with weanling pigs, effects of supplemental dietary Se (3 ppm as sodium selenite) on the toxicity of dietary Cd (50 ppm as cadmium chloride) were tested and effects of dietary Cd on Se metabolism were observed. Levels of Se and Cd did not affect body weight gain. Levels of Se were higher in blood (P < 0.005) and in liver (P < 0.01) in Se-supplemented than in unsupplemented pigs. In Se-supplemented but not in unsupplemented pigs, addition of Cd to the diet reduced Se from 1.179 to 0.202 µg/g in blood and from 1.74 to 0.61 µg/g in liver. The effect of Cd in depressing blood Se in Se-supplemented pigs was present at week 2 and persisted through week 6. Glutathione peroxidase (GSH-Px) activity in plasma was elevated in Se-supplemented pigs (P < 0.005). Addition of 50 ppm dietary Cd doubled activity in pigs fed the diet unsupplemented with Se but not in pigs fed the Se-supplemented diet (Se × Cd, P < 0.005). Hematocrit was depressed (P < 0.005) by 50 ppm Cd at both levels of dietary Se at 2, 4 and 6 weeks. No gross or histopathological lesions were observed. The data suggest that at the levels of Se and Cd used, high dietary Se reduces accumulation of Cd in liver. Dietary Cd depressed tissue retention of added inorganic dietary Se, probably by interfering with absorption, and at a nutritionally adequate but not excessive level of dietary Se, Cd stimulated plasma GSH-Px activity.