The Effect of Dietary Arsenic Additions on the Distribution of Selenium and Iodine in Eggs and Tissues of Laying Hens

The aim of the work was to determine the short-term effect (19 days) of dietary As additions (30 g As/g in the form As₂O₃) on the Se and I concentrations in eggs and tissues of 49-week-old Rhode Island Red laying hens. Se and I concentrations were determined in eggs collected from the 8^th to the 10^th and from the 17^th to the 19^th days of the experiment. After 19 days, blood was collected by anterior heart puncture, and after slaughter the liver, kidney, lung, muscle (musculus pectoralis superficialis) and feathers were collected. Se and I concentrations were determined by radiochemical neutron activation analysis and the results expressed on a dry matter basis. In the control and the exposed group, the highest Se concentrations were found in kidney, followed by liver, blood, lung, muscle, and feathers. In the control group the highest I concentration was found in feathers, followed by kidney, blood, lungs, liver, and muscle. In the trial group, the order was almost the same, except that blood concentration was lower than in liver. As₂O₃ added to the feed significantly increased the Se concentration in the lung (p = 0.0216), I concentration in muscle (p = 0.0112) and significantly decreased I concentration in blood (p = 0.0371). It had no effect on the concentrations of Se and I in egg yolk and white.