关键词: 球虫, 球虫病, 疫苗, 抗原, 鸡, 免疫

Abstract: Avian coccidiosis is a major parasitic disease of economic importance in poultry industry and is controlled using prophylactic medication.The increasing incidence of drug resistance and the consumers’ increasing concern about the sanitation of poultry products prompt the development of vaccine against coccidiosis.Although being proved to have definitely effects against coccidial infection，live vaccine will be altered by molecular vaccine due to its possibility of rejuvenation.Hundreds of proteins involved in the process of invasion of the host cells have been described，seldom of them was proved to have a ideal effect against coccidiosis when the related genes were expressed in prokaryotic system.DNA immunization has been widely used in recent years as a novel vaccine delivery system to induce host high levels of cellular immune responses.

Key words: eimeria, coccidiosis, vaccine, antigen, chickens, immunity