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  The giant liver fluke, Fascioloides magna, is of interest to wild-life managers, veterinarians and researchers, due to its unusual body size (3–10 cm), high pathogenic potential and because it is continuously spreading to new areas, especially in Europe. Annually, the number of cases of animal infections (mainly cervids and bovids) caused by this fluke is monitored in many European countries, including the Czech Republic (with some foci of prevalence over 90%). During the years 2009 and 2010, 1622 survey forms focused on monitoring of fascioloidosis were distributed in the community of “Czech Inspectors of Hunted Game” (CIHG), and 21.3% of forms containing positive or negative response about F. magna occurrence were returned. The administrative units monitored by particular CIHG, who answered the forms, were geographically equally distributed and therefore we believe that also the recorded distribution of F. magna in wild-life animals reflects the real situation in the Czech Republic. A significant number of cases of F. magna infection were repeatedly reported from areas in the south-west part of the Czech Republic. Moreover, our report contains also some unique records of several new F. magna foci in the western (close to the German border), northern (close to the Polish border) and central parts of the Czech Republic, supporting the assumption that the parasite is spreading further throughout Europe. In five game administrative units F. magna infection was directly confirmed by examination of dissected deer livers or by microscopic examination of coprological samples, followed by isolation of DNA from adults and eggs and further molecular analyses. Fascioloides magna intermediate host snails (Galba truncatula and Radix spp.) were collected during 2009 and 2010 from different localities of the Czech Republic, kept in aquaria, examined for shedding of F. magna cercariae, dissected and parasite/snail DNA was isolated. After PCR with specific primers for parasite/snail internal transcribed region number two (ITS-2) the obtained sequences confirmed identification of the following species: F. magna, G. truncatula, R. peregra, R. lagotis, R. labiata and R. auricularia. Although it has been demonstrated that the number of areas with positive cases of fascioloidosis is still growing, the risk of pathogenic impact of F. magna on populations of free-living animals and farming cervids/bovids is generally underestimated.

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Eurasian spruce bark beetle, Ips typographus is a destructive pest of the Norway spruce (Picea abies). Recent outbreaks in Europe have been attributed to global warming and other anthropogenic impacts. Bark beetles are guided by multiple complex olfactory cues throughout their life cycle. Male-produced aggregation pheromones, comprising 2-methyl-3-buten-2-ol and cis-verbenol, have been identified as the most powerful attractants for dispersing conspecifics. In addition to host trees, bark beetles interact with multiple organisms, including symbiotic ophiostomatoid fungi, which may promote beetle colonization success and offspring development. Previously, in a short-distance laboratory assay, we demonstrated that I. typographus adults are attracted to the volatile organic compounds (VOCs) produced by three symbiotic fungi: Grosmannia penicillata, Endoconidiophora polonica, and Leptographium europhioides. Furthermore, the abundant fusel alcohols and their acetates were found to be the most attractive odorants in the fungal VOC profile. In this study, using a long-distance field-trapping experiment, we analyzed the role of fungal VOCs as attractants for dispersing I. typographus. Two types of fungal lures were tested in combination with pheromones in traps: (1) live cultures of fungi grown on potato dextrose agar (PDA) and (2) dispensers containing synthetic fusel alcohols and their acetates in equal proportions. Subsequently, the composition of VOCs emitted from live fungal lures were analyzed. We found that the symbiotic fungi synergistically increased the attraction of beetles to pheromones in field traps and the attractiveness of live fungal lures depended on the fungal load. While one Petri dish with E. polonica, when combined with pheromones synergistically increased trapping efficiency, three Petri dishes with L. europhioides were required to achieve the same. The synthetic mix of fungal fusel alcohols and acetates improved the catch efficiency of pheromones only at a low tested dose. VOC analysis of fungal cultures revealed that all the three fungi produced fusel alcohols and acetates but in variable composition and amounts. Collectively, the results of this study show that, in addition to pheromones, bark beetles might also use volatile cues from their symbiotic fungi to improve tree colonization and reproductive success in their breeding and feeding sites.