To the question of evolution of infectious diseases of animals
In the article the different aspects of fight of animals and timber-toe are examined by the exciters of infectious diseases, role of pathogens in the evolution of animals and man. The biological consequences of cooperation of animals and pathogenic organisms and basic factors of genetic selection are analysed. The numerous forms of polymorphism of, are resulted which determine the degree of receptivity of clinical display at many infections. A conclusion is done, that selective пресінг microorganisms shows up from the direct selection et the cost of surpluses of death rate of diseased to integration in the genome of animal. It is marked, that as a result of immunological пресінгу, caused a mass vaccination, take a place change in популяції of exciter which results in appearance of him the antigen changed variants. New knowledges about cooperating of animals with exciters require new approaches in a fight against infectionsi illnesses of man and animals.