Veterinary Drugs Residues: Ectoparasiticides

Food-producing animals are infected by a number of ectoparasites that can result in production losses. Control of these parasites is largely based on the use of chemicals that are either applied topically to the skin or sometimes given parenterally. Most ectoparasiticides are neurotoxins, exerting their effect on the nervous system of the target parasite. As a result of frequent and inappropriate use, resistance of arthropods to the lethal effects of parasiticides has been reported in many parts of the world. Ectoparasiticides can also be toxic to mammals and restrictions are therefore applied to many of the compounds indicated for use in food-producing animals to ensure that unacceptable residues are not present in products intended for human consumption. Consequently many international organizations and countries have issued their own pesticide maximum residual limits in international trade.