AbstractsBiology & Animal Science

Many aspects of wildlife diseases, especially in Mediterranean ecosystems, including ecological parameters and management practices, remain uncertain. The European brown hare (Lepus europaeus) is a major wildlife species in Mediterranean Basin taking into account its importance as a prey for many carnivore species and as a huntable species. The recorded widespread mortality by European Brown Hare Syndrome (EBHS), indicates this viral disease as the most important disease for hares in Europe. This PhD thesis presents a series of studies conducted with the aim to investigate several aspects of the ecology and management of hare and European Brown Hare Syndrome Virus (EBHSV) in Macedonia, Hellas. Mediterranean ecosystems are characterized by a variety of ecotopes. The free access of Hellenic hunters in countryside gave the opportunity to study hare harvest and EBHSV prevalence in different ecotopes. During the study, 291 hares were collected by the hunters. The ecotope, where each hare was initially found by the dogs, was recorded and a population index was calculated. Moreover, the PCR was used for the detection of EBHSV. The greatest harvest in unit area was recorded in areas with mosaic of cereals and woody vegetation; in contrast the lowest harvest took place in forestlands. EBHSV had widespread distribution even in isolated areas and the prevalence was in an endemic stability of 17.8%. EBHSV has higher prevalence in Olive groves, followed by mixed cultivations and shrublands. Population index is related positively with EBHSV prevalence and harvest. Harvest is not related significantly with EBHSV prevalence. In a second step, a more detailed study was taken place with the contribution of multivariate statistics and Geographic Information Systems (GIS). It was found that prevalence increases in areas with higher hare abundance; closer to paved road network and in lower altitudes. Secondly, a potential distribution map was constructed to show the relative risk of EBHSV in the study area.Associations of EBHSV infection, sex, age, body condition and spleen mass were studied in 259 hares collected. Data showed a sex-biased prevalence with twice as many males infected with EBHSV than females, indicating a sexual dimorphism in disease exposure or susceptibility. EBHSV infection was not related to hare body condition and a higher body condition was found in males than in females. Adults had a higher ratio of infected animals than young but this difference was not found to be statistically significant. Adults also had higher spleen mass thus indicating past infections. An enlarged spleen was more frequently found in hares positive for EBHSV and a negative relation was found between spleen mass and body condition thus indicating energy consumption for immune defense investment. Ecosystem disturbances, such as wildfires, are driving forces that determine ecological processes, including diseases. Species respond differentially in wildfires, having diverse post-fire population evolution. Hare relative abundance, age ratio, diet…