RESUMO
Infectious diseases of animals are the subject of continuous concern. On the one hand there are some diseases which have not yet been described and on the other hand the presence of microbial agents is proved also in diseases which have been considered non-infectious. Undoubtedly, microbes and parasites take part also in the development of malignant transformation of cells. The question of possible transfer of animal oncogenic microorganisms (retroviruses in particular) to humans remains open. The study points to the changes in the incidence of orthopoxviruses which occurred after eradication of human variola and the increasing importance of bartonelloses. Disease prevention in animals is affected to an increasing extent by DNA recombinant methods. So called "Gene farming" has developed, consisting in production of narrow-profile therapeutically important proteins via animal bioreactors. We enter a period in which the resistance of animal organism begins to affect the transfer of genes encoding non-specific and specific protective mechanisms of organisms. (Tab. 7, Ref. 39.)
