[Effects of Increasing Dietary Iron and Administering Oxytetracycline to Laying Hens on Oxytetracycline Residues and Their Activity in Eggs

Abstract

An experiment was conducted to elucidate the effects of increasing dietary iron on the reduction and inactivation of oxytetracycline residues in eggs, in which the hens administered oxytetracycline. Laying hens were administered oxyteracycline via drinking water with 2 g/l for 7 succcessive days and fed on the diet that increased the iron content by adding 100 ppm, 200 ppm and 300 ppm. The iron content, residue and activity of oxytetracycline in eggs, both in white and yolk, were evaluated on 4th and 6th of administering oxytetracycline. Results indicated that the iron in egg white could not be increased due to the increased of iron in dietary. Therefore, oxytetracycline residue existing in egg white could not be inactivated. However, addition of 200 ppm iron in dietary increased the iron content, reduced and inactivated oxytetracycline residue in yolk. Whereas the addition of 300 ppm iron in dietary eliminated oxytetracycline residue in yolk. Keywords: oxytetracycline, iron, hen, egg, residue, activity