ENGLISH VERSION

ZESZYT 363

The characteristics of the Anoplocephala perfoliata invasion in horses in relation to molecular and proteomic aspects of the invasion 
zeszyt 363, ss. 110

Changes in the structure of horse husbandry and pasture management practices in Poland have a positive influence upon increase prevalence of some internal parasites including invasions of tapeworms from species Anoplocephala perfoliata. Due to the diagnostic problems (lack of sensitivity of ante mortem diagnostic tests), as well as the general belief of the low pathogenicity of Anoplocephala perfoliata, so far detailed studies which focus on the epidemiologic and pathologic aspects of this parasite has not been conducted in Poland. Moreover, most predominant types of horses seen in Poland in recent years, were breeds developed primarily for work. Its specific farming system minimizes the risk of infestation with A. perfoliata. These facts led to the marginalization problem of equine anoplocephalosis. Currently, when the number of horses kept in herds has increased, soliped tapeworms are becoming an important pathogen. Its invasions occur in different regions of the country, which is evidenced in the monitoring of spread of invasions.

The lack of data concerning the extent of the invasion as well its pathogenesis in the context of its genetic variety (molecular and proteomic features within the Anoplocephala perfoliata species) has inspired this study. Thus the aim of the study has been describing the prevalence of A. perfoliata invasion in horses kept in various systems, its intensity and extent in organisms, as well as the dynamics of A. perfoliata invasions, likewise conducting a comparison of the genome parts and protein profile of the parasite depending of the manner the tapeworms’ spread into the intestine. 
The research encompassed of 827 horses, at the coprological examination, evaluating it sedimentation-flotation method, the prevalence as well as the influence various breeding factors on the spread of the A. perfoliata invasion in various maintenance systems. In addition, post-slaughter examinations were conducted on 1626 horses and included: evaluating the intensity of the invasion, analysis of the pattern localization tapeworms in intestine. Sequences of ribosomal RNA and proteome tapeworms isolated from different pattern localization were analyzed as well as a comparison of the pathogenic influence was conducted.

The greatest prevalence of A. perfoliata was demonstrated in stud farm (30%), 58.33% of the infected herds. It was demonstrated that boggy pastures had a great impact on the spread of the A. perfoliata invasion. In post-slaughter examinations 6.6% extensiveness of the invasions with various intensities encompassing 2 to 2069 tapeworms were confirmed. The occurrence of tapeworms in characteristic clusters [a concentrated form of distribution] in 36.11% of the invasions were confirmed, which were characterized by a significant pathogenic impact. Invasions of medium intensity dominated, within a range of 11 to 50 and 51 to 100 tapeworms. The greatest percentage of infections of animals was demonstrated in animals from 5 to 20 years of age with a marginal extensiveness in foals up to one year of age or young horses from 1 to 3 years of age. It was confirmed that invasions occurred more frequently in mares and geldings than in stallions; moreover, they did not affect the nutritional condition of the infected animals. The range of the invasion was most often limited and concerned in the ileocecal valve and the head of the cecum. The dynamic of the course of the invasions during the early fall peak period has been described. It has been indicated that of primary significance in the endemic retention of the invasions are parasites that spent the winter in the alimentary canal of horses; of lesser significance are tapeworm larvae that spent the winter in hosts. In the histopathological examinations a correlation between the number and manner in which parasites spread and the increasing pathological changes in intestinal walls was demonstrated. Particularly in the case of invasions in which parasites occur in clusters the reduction of the number of goblet cells and ganglia of the intestinal nervous system as well as hypertrophic and degenerative alterations in the mucous membranes and sub-mucous membranes has been confirmed. The multiplication of the number of lymph follicles as well as numerous of cell infiltration confirm the inducement of the inflammation of the intestinal walls as the major pathological mechanism of the invasions. Comparative examination of a fragment of the parasites’ genome indicated essential differences in the sequences of specific isolates, confirming the occurrence of several groups of similarities, especially regarding sequences of conservative regions (gen 5.8S rRNA). The 2D electrophoresis technique demonstrated an additional difference in the occurrence and expression of certain proteome proteins of A. perfoliata, which confirms the non-uniformity of the species.

The research proved that horses cestodiasis occur often and are a significant factor influencing the state of health of horses in Poland. The conducted molecular and proteomic analyses only constitute an attempt at indicating the factors responsible for the choice of particular means of the spreading of tapeworms in the intestines of a host, and through this means to indicating the factors responsible for the differentiated pathogenicity of the invasions.