There are many types of animal epidemic diseases in China, and the epidemic is long, and it is difficult to control once the disease has occurred. The incidence of animals should be mainly prevention, and the key to prevention is to prevent infection. Therefore, to prevent pathogen infection, we must first fully understand the pathogen. Understand the structure and function of the pathogen's macromolecules so that preventive preparations can be targeted and effective measures taken to prevent pathogens from invading animals can cause disease. As the study of the structure and function of pathogenic macromolecules has far-reaching guiding significance for animal population disease prevention and control technology, the United States, Europe, Japan and other developed countries have placed the research in this field at the forefront of veterinary scientific research. Since the 1980s, they have focused on the study of the primary structure of pathogenic genes and their products. The main progress has been the following: 1. Physical maps and chemical maps of almost all animal viruses have been mapped; The genomic nucleotide sequence and the amino acid sequence of the encoded protein of all animal virus reference strains; 3. The structural proteins, non-structural proteins and intermediates of some animal viruses were isolated and expressed, and the pathogenic and immune mechanisms of some protein products were analyzed. 4. The construction of some animal virus active cDNA, through the deletion, point mutations, gene recombination, analysis of the regulation and pathogenic function of some viral genes; 5. Through the molecular epidemiological studies, the use of computer technology has drawn several important Molecular phylogenetic tree of pathogens, to understand their phylogenetic relationships; 6. Gene libraries of some complex pathogens were constructed, and biological functions of the genes and their products with useful values ​​were analyzed. The above studies have provided guidance and promoted the understanding of the genetic variation and the immune mechanism of animal pathogens, the establishment of new anti-inspection technologies and the development of new preventive preparations. It can be expected that the prevention of animal disease in the next century will be dominated by modern biotechnology and genetic products, and the results of the study of the structure and function of pathogenic macromolecules will be the main basis. Therefore, developed countries and even some developing countries have basic research plans to incorporate this topic into the 21st century. The study on the structure and function of animal pathogenic macromolecules in our country was a decade or so later than that of developed countries. The real research was conducted in the mid to late 1980s. Over the past decade, the following progresses have been made: 1. We have cloned the immune genes of the pathogenic groups of almost all animals in China and analyzed the primary structure; 2. We analyzed or are analyzing swine fever virus, equine plague virus and blue ear disease. Viruses, etc., represent the whole genome sequence of the strain; 3. Molecular epidemiological studies of swine fever, blue ear disease, chicken ND, chicken bursal disease, and infectious bronchitis are being conducted to map the phylogeny of these pathogens. (4) Using the strong and weak strains isolated or cultivated in China, preliminary studies were conducted on the pathogenic genes of equine pluripotent, pseudorabies, chicken Marek’s disease, chicken NDV, chicken bursal disease virus, and avian influenza virus. The sequence characteristics and the mode of action of the encoded protein; 5. The use of antisense nucleic acids and nucleic acids to block the gene expression principle, studied the possibility of blocking the replication process of swine fever virus, obtained anti-virus infection cell lines and transgenic Animals; 6. Constructed cDNA libraries of some complex pathogens such as parasites and bacteria, and cloned a few functional genes. The above research shows that China has made some significant progress in the study of the structure and function of animal pathogen macromolecules and has initially established a theoretical system that is urgently needed for national epidemic prevention. It should be noted that there is still a certain gap between China’s current research level and the developed countries, and there are still many tasks to be done. China is a large agricultural country. Animal husbandry accounts for 1/3 of the total agricultural output value and is a pillar industry of agriculture and rural economy. In the past two decades since the reform and opening up, animal husbandry has made great progress, but there are still many problems that need to be resolved. According to statistics, animal diseases in normal years have reduced livestock and poultry listings by 10% to 30% (5% to 10% in developed countries), resulting in huge losses. The proportion of China's exports is only 0.2% of the total output (a few dozen percent of developed countries). The main reason for this situation is the epidemic of fauna in intensified conditions. With the improvement of global scientific and technological advancement and improvement of animal health conditions, and the imminence of China’s accession to the WTO and the improvement of people’s living standards, the public’s demand for “safety†has become increasingly high. In the future, the production and export of animal products in China will face even more severe challenges. . At present, the vaccines for prevention are mostly made of intact pathogens. Even in production and use, they require even pathogens with high virulence, and there is the danger of spreading and maintaining pathogen circulation in the natural world. At present, the eradication of the epidemic has been controlled or eliminated. In the face of prolonged prevention, the long-standing impending catastrophe and emerging epidemics need to seek new theoretical guidance, carry out molecular etiology research, find out the molecular structure of the pathogen, Analyze the genetic mutations and pathogenic immunity-inducing functions, and provide ideas and scientific basis for the new anti-infective technology. From the analysis of veterinary epidemic prevention technologies and industrial development trends, the prevention and inspection technologies and biological products of animal epidemics in the next century will be dominated by modern biotechnology and genetic products. The scientific basis for the development of these technologies and products is inseparable from the structure of pathogenic macromolecules and Functional research. Therefore, the use of molecular biology theory and modern technology to study the macromolecular structure and function of animal disease pathogens, so as to understand the nature of life activities of pathogens at the individual, cell and molecular level, this is undoubtedly the current and future animal disease prevention and control technology An important scientific support.