Acceleration of mercury excretion in broilers

Abstract

VARION AD (NIKE, Balatonfűzfő) anion exchange resin in the form of EDTA or Cl was used as a protective agent against mercury (II) ions. Where the anion exchanger pretreated with EDTA was fed together with the contaminated feed the VARION AD (EDTA) bound the great majority of these heavy metal ions in the digestive tract, thus inhibiting their absorption. With regard to selectivity, it is advantageous that the alkali metals do not form EDTA complexes; at the same time, the chelates created by the alkaline earth metals with EDTA are substantially less stable than those formed by mercury. In both cases this protective effect was examined in four-week-old Ross 308 type broiler cocks. The mercury was administered to the birds in a single dose, in the form of HgCl2 labelled with Hg-203 isotope; the feed supplemented with the protective agent was fed ad libitum. In the subsequent feeding period the mass and radioactivity concentration of the excreta were measured once daily. On the 10th day the birds were slaughtered, after which radioactivity concentration in the breast muscle, the liver and the kidney was measured. On the basis of the results obtained it was established that even at concentrations as low as 20 g per kg both protective agents increased mercury excretion significantly and reduced the quantity of mercury accumulating in the various organs (P<0.05).