Mặc dù thường được coi là một nhóm duy nhất của hóa chất, thuốc thú y là một nhóm đa dạng các sản phẩm khác nhau có chứa một loạt các hợp chất thuộc lớp hóa học khác nhau và được sử dụng cho một loại đa dạng của điều kiện (xem Bảng ở Chương 2). Antiparasiticides kiểm soát ký sinh trùng bên ngoài như bọ ve hoặc biển chí (ectoparasiticides), ký sinh trùng nội bộ như sâu tiêu hóa và protozoans (endoparasiticides), hoặc cả hai (endectocides). Thuốc kháng sinh được sử dụng để điều trị và phòng chống. | 3 Environmental Risk Assessment and Management of Veterinary Medicines Joop de Knecht Tatiana Boucard Bryan W. Brooks Mark Crane Charles Eirkson Sarah Gerould Jan Koschorreck Gregor Scheef Keith R. Solomon and Zhixing Yan INTRODUCTION Although often considered as a single group of chemicals veterinary medicines are a diverse group of different products containing a broad range of compounds belonging to different chemical classes and used for a diverse assortment of conditions see Table in Chapter 2 . Antiparasiticides control external parasites such as ticks or sea lice ectoparasiticides internal parasites such as gastrointestinal worms and protozoans endoparasiticides or both endectocides . Antibiotics are used for the treatment and prevention of bacterial infections whereas fungicides are administered to treat fungal or yeast infestation. Hormones regulate growth reproduction and other bodily functions. Veterinary medicines are used to treat many groups of animals such as terrestrial and aquatic animals that are used for food and companion animals. Taxonomically the groups include mammals . cattle horses pigs sheep goats dogs and cats birds . chickens and turkeys fish and invertebrates . bees lobsters and shrimps . This diverse group of animals necessitates a variety of treatment techniques. Veterinary medicines are administered orally parenterally intramuscular intravenous and subcutaneous injection and topically dip spray pour-on spot-on ear tag collar and aquaculture water baths . Veterinary medicines are not usually directly applied to the environment except for some aquaculture treatments although manure drainage from sheep dip releases from aquaculture facilities scavenging of carcasses and other environmental releases result in environmental exposure to nontarget organisms. Releases of veterinary medicines into the environment can take place at any step in the life cycle of the product. However veterinary medicines have a 21 2009 by the .
