Salinomycin was approved for chickens in 1983. It is a sodium salt of a polyether monocarboxylic acid produced by Actinomycetes sps. Salinomycin sodium is feed additive. It is used in the prevention of coccidiosis in poultry caused by E.coli and salmonella.enterica. Salinomycin is active against certain Gram-positive bacteria, whereas Enterobacteriaceae are resistant. In addition, it is known that salinomycin has an inhibitory effect on Clostridium perfringens, therefore the use of salinomycin leads to a decrease in the incidence of necrotic enteritis in broiler chickens. Salinomycin is absorbed to a certain extent in the chicken and extensively metabolized although the concentration present in the edible tissues of the animals are very low and scarcely detectable. Salinomycin is considered as the marker residue and skin/fat as the target tissue. Salinomycin produces relatively low residue levels in the eggs compared with other polyether ionophores. chickens. Salinomycin is absorbed to a certain extent in the chicken and extensively metabolized although the concentration present in the edible tissues of the animals are very low and scarcely detectable. Salinomycin is considered as the marker residue and skin/fat as the target tissue. Salinomycin produces relatively low residue levels in the eggs compared with other polyether ionophores.