Non-parasitic phase of ticks is the most critical period of their life cycle. During of host period the ticks must maintain the water homeostasis and must find a host for feeding. Body water homeostasis is one of the most important processes that influences tick survival in nature and transmission of pathogens. Structure of intergument, particularly the waxy lipids in the epicuticle, and structure of peritremes restrict the loss of water from tick body. The water lossesmay be compensated by uptake of water vapour from the atmosphere. The critical equilibrium humidity of tick species of Ixodidae family range from 70 to 96% r.h. During non-feeding period, behaviour of ticks contributes to the maintenance of body water. The ticks aviod the microhabitats where loss of water may be accelerated.
Ticks respond to host stimuli, such as higher CO₂ concentrations, vibrations, odour, touch, radiant heat ad kairomones. The behahaviour al reactions to these host stimuli vary among tick species. Among these arthropods hunter (actively running in the direction of host) or ambusher ticks (passively waiting for host on the vegetation) occur. Hallers organ. palpal organ, cheliceral organ and receptors on scutum and alloscutum are involved in tick feeding behaviour.
Various kinds of morphological anomalies, i.e. general (the changes in the shape and the asymmetry of body, the duplication of body, the nanism, the gigantism and the gynandromorphism), and local (oligomely, atrophy, polimely, heterosymely, symely, schistomely, ectomely, heteromorphose, disturbances in the structure of leg segments, cyclopy) occur in Ixodida The anomalies within taxonomically important structures make the determination of tick species difficult or even impossible. Therefore, the anomalies deforming systematic features of different instars from Argasidae and Ixodidae families were first of all taken into account.
Toxins have been shown to present in the salivary glands, whole body extracts, and eggs of ticks. They cause histological lesions in the skin, and in various organs of tick hosts. Among toxicoses, tick paralysis is of the greatest medical and veterinary importance. Toxins are secreted by cells „b" of acinus II in salivary glands during tick feeding.
The influence of Lugol’s solution on the embryonic development and egg hatch of Argas (A.) reflexus at a temperature of 25°C and relative humidity of 30% was investigated. The iodine compound was found to cause high mortality of eggs (23.1%) and embryos (34.8%). In these experiments only 40.9% of the eggs studied hatched into normal larvae. Interesting anomalies of Argas (A.) reflexus larvae, developed under these conditions, were also described.
Arthropod-borne diseases still pose a serious health problem worldwide. Epidemiological consequences result from various environmental connections and interaction between parasites and their host, including host specificity of parasites and transmitted pathogens. The ixodid ticks (Ixodida) occupy a prominent position within the group of parasites as being vectors on the northern hemisphere in temperate climate zone. They are blood-feeding ectoparasites with different host specificity and capacity to transmit various pathogens. Feeding on many mammals (including humans), birds, reptiles and amphibians they present a great medical problem. For example, Ixodes ricinus can infest several hundred species of animals. It is a vector of pathogenic viral, bacterial and protozoal organisms, including Borrelia burgdorferi sensu lato complex which is the etiological agent of Lyme borreliosis. The competent reservoir hosts of Borrelia include many common species of small and medium-sized rodents as well as several bird species. Epidemiological consequences are complicated by the fact that specific Borrelia genospecies are associated with particular reservoir hosts. Thus, detailed analysis of epidemiological consequences requires a comprehensive knowledge of the biology and ecology of vectors, pathogens and their reservoirs including host specificity of ticks. Spatial modelling tick-borne risk in time and space is made possible by the use of remote sensing and techniques of geographical information system (GIS).