Dr. Murai Éva szerk.: Parasitologia Hungarica 22. (Budapest, 1989)
our country as well as medical and veterinary practice have shown that an effective strategy (theory) and tactics (practice) of struggle against associative diseases are possible only after elucidation of the structure and function of microparasltocenoses . The solution of major problems of parasitocenology requires, first of all, the development of complex interdisciplinary research which would result in elucidation of specific (particular) laws of formation and function of parasitic ecosystems, factors regulating interrelationships of their members, evolutionary and genetic events which call forth the historical evolution of these systems, bioenergetic metabolism and information. Interdisciplinary research, integration of parasitological disciplines, the development of the common scientific language for all the fields of parasitology will be accompanied by more and more profound knowledge of the essence and regularities of parasitism. There is no need for any special proof to state that any special parasitologic discipline alone is not able. The systemic approach represents one of the most important trends of methodology of scientific cognition that orientates researchers towards the study of objects of complex structure ass systems. It favours the understanding of the wholeness of an object, elucidation of multiform types of relations of its compounds, the reproduction of a system under investigation in our mind in the form of objective reality. The basis of a systemic approach is the notion of the world as the most complicated system of Interrelated, interdependent, interacting and hierarchically coordinated forms of the matter, which reflect organizational levels as well as the nature, trends and successive steps of its development. A systemic organization of the living nature is revealing itsel f in the structural and functional coordination of all écologie systems of different constructive range and structural level, united in a supercomplex global system - ecosphere. A systemic approach is the matter of principle in the solution of Interdisciplinary problems, since the integrative trend is one of its basic functions. The development of this approach will contribute to the perfection of systemic style of reasoning of parasitologists, to the formation of theory and scientific method of parasitocenology. The concept "parasitic ecosystem" can be applied to hierarchic systems of any levels of complexity and dimension beginning with microparasltocenosis and the parasitic subsystems it unites. In addition to parasites and conditionally pathogenic organisms this system includes also the hostal environment and associations of free-living generations of pathogens together with the concrete external environment they are surrounded by. Research work and characteristics of the parasitic ecosystems' hierarchy will profit by being regarded within respective biogeocenosis. The term parasitocenotic ecosystem should be considered as an assemblage of populations of parasitic species and conditionally pathogenic organisms on different stages of development existing within biogeocenosis together with their definitive and intermediate hosts and carriers. This system^ as it Is shown on the table, comprises two subsystems: parasltocenosis (in the new meaning) and parasitocenogenic hemisystem which rallies hemipopulatlons of all free-living generations of parasites. The latter, penetrating into the host body, take part in the formation of micropopulations of periodic parasites which, together with micropopulations of constant parasites, form microparasltocenoses. All microparasltocenoses developing within the population of a host species build up monoxenous parasitocenosis, microparasitocenogenic hemisystems being included into a monoxenous parasitocenogenic hemisystem. The organization of each level of parasitic systems is characterized by Its structure, specific regularities of function, special relationships of its compounds, and constant interchange of stuffs and energy with hostal and external environments.
