Untersuchungen an Zootieren : Einsatz von Raubwanzen als „lebende Spritzen“ und Einflüsse verschiedener Faktoren auf die Parasitierung
Triatomines can be used as an alternative means for obtaining blood samples from vertebrates instead of the conventional method via syringe and needle. As greatest advantage preponderates the minimal invasiveness for the host. Capture or anaesthesia are not applicable. If the method with blood-sucking bugs was modified to the different host species like reptiles, birds or mammals, the „living syringes“ were successfully used in twelve European countries and 47 institutions and 72 different species. These were in total four different reptile, three bird and 65 mammal species. Exclusively the triatomine Dipetalogaster maxima was used in the present study because of the highest aggression and biggest blood volume which could be obtained. The concentration of potassium was useful as approximate value for the beginning of the hemolysis. The present study verified the reduction of glucose in the stomach of the blood-sucking bugs was verified for the first time. The genetic subspecies determination of aardvarks did not result in a clear classification, but the hypothesis that blood sucking bugs can be used for the blood sample collection was confirmed. Also the screening for epizootic diseases like brucellosis, tuberculosis, malaria and blue-tongue disease were successful. All results were identical in both collection methods. No false-positive and false-negative results were found. The stress hormone analysis proved again the advantage of the minimal invasive method via blood-sucking bugs. More problems occurred at the endocrinological analysis for Progesterone. Progesterone levels were 6 fold higher in 78% of the samples of Eland antilopes in comparison to the conventional method. Although progesterone concentrations could be detected in the samples, the accuracy of the method should be examined if this method is only suitable for the specific methodology in the measurement of progesterone concentrations; for house rats this method can be recommended. Parasite-host-systems are affected by different psychoneuroimmunologi¬cal factors. These factors can affect the balance to the advantage or disadvantage of the host or the parasite. Such factors are the gender, age, social rank and reproduction. In the present study the impact of the appropiate factors of intestinal parasites on suricates, white-lipped deer, Siberian ibex, king penguins, chicken, house sparrow and diamond doves were examined. In three species (chicken, house sparrow and Siberian ibex) the males had the higher parasitemia and respectively the females of the four other species. Not all results were significantly different and further studies are planned. An influence of the age on the immune system was also verified, e.g. the offspring of suricates possessed the highest parasite burden. Also the younger white-lipped deers had the higher numbers of parasites. The social hierarchy as psychoneuroimmunological factor was well presented in the study at the suricates with an increasing parasitaemia with decreasing rank in the hierarchy. Highest parasitaemia were found (in most cases highly significant) in the subordinate individuals. Similar results were detected in the white-lipped deers. The influence of the reproduction could be detected in the examined bird species. The breeding diamond doves for example had a higher parasitamia in comparison to the non breeding birds. The breeding pair of king penguins had a higher parasite burden in comparison to the other individuals. The higher parasite amount of the breeding birds correlated to the observed increased stress in that case. Also in future studies the use of the blood-sucking bugs for determinations of stress hormone levels will hopefully deliver much more insights for the interesting aspects of the influence of psychoneuroimmunological factors on the host-vector interactions of parasites.