snails Dotaz Zobrazit nápovědu
In freshwater ecosystems, snails can significantly influence the competition between primary producers through grazing of periphyton. This activity can potentially be modified by trematodes, a large group of parasites which mostly use molluscs as the first intermediate host. Available studies, however, show contradictory effects of trematodes on snail periphyton grazing. Here, we used four different freshwater snail-trematode systems to test whether a general pattern can be detected for the impact of trematode infections on snail periphyton grazing. In our experimental systems, mass-specific periphyton grazing rates of infected snails were higher, lower, or similar to rates of non-infected conspecifics, suggesting that no general pattern exists. The variation across studied snail-trematode systems may result from differences on how the parasite uses the resources of the snail and thus affects their energy budget. Trematode infections can significantly alter the grazing rate of snails, where, depending on the system, the mass-specific grazing rate can double or halve. This underlines both, the high ecological relevance of trematodes and the need for comprehensive studies at the species level to allow an integration of these parasite-host interactions into aquatic food web concepts.
- MeSH
- ekologie MeSH
- ekosystém MeSH
- hlemýždi parazitologie MeSH
- infekce červy třídy Trematoda parazitologie MeSH
- interakce hostitele a parazita fyziologie MeSH
- perifyton * MeSH
- potravní řetězec MeSH
- přijímání potravy fyziologie MeSH
- sladká voda parazitologie MeSH
- Trematoda izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Drilus beetle larvae (Coleoptera: Elateridae) are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae) species in Greece. We observe that Drilus species may be facultative or obligate Albinaria-specialists. We map geographically varying predation rates in Crete, where on average 24% of empty shells carry fatal Drilus bore holes. We also provide first-hand observations and video-footage of prey entry and exit strategies of the Drilus larvae, and evaluate the potential mutual evolutionary impacts. We find limited evidence for an effect of shell features and snail behavioral traits on inter- and intra-specifically differing predation rates. We also find that Drilus predators adjust their predation behavior based on specific shell traits of the prey. In conclusion, we suggest that, with these baseline data, this interesting predator-prey system will be available for further, detailed more evolutionary ecology studies.
- MeSH
- biodiverzita MeSH
- brouci * MeSH
- hlemýždi * MeSH
- larva MeSH
- molekulární evoluce MeSH
- predátorské chování * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Řecko MeSH
Schistosomiasis is a snail-borne disease that has a considerable impact on human and animal health, particularly in sub-Saharan Africa. The intermediate hosts of the schistosome parasites are freshwater snails of the genera Biomphalaria Preston, 1910 and Bulinus Müller, 1781. In order to identify existing gaps in the spread of the disease in the Democratic Republic of Congo (DRC), this study compiled the available knowledge of the distribution, population dynamics and ecology of the intermediate hosts of schistosomiasis. A systematic literature search was conducted in PubMed, Embase and Scopus for all malacological studies on schistosoma intermediate hosts in DRC published between 1927 and October 2022. A total of 55 records were found, of which 31 met the inclusion criteria: these were published field and experimental studies conducted in the DRC and focused on snails as intermediate hosts of schistosomes. The analysis of these studies revealed that more up-to-date data on the distribution of snail intermediate hosts in the DRC are needed. Moreover, ecological factors have been less studied for Bulinus species than for Biomphalaria species. These factors play a crucial role in determining suitable snail habitats, and the lack of comprehensive information poses a challenge in snail control. This review makes it clear that there are no current malacological data in the DRC. There is a clear need for molecular and ecological research to update the exact species status and population dynamics of all potential intermediate host species. This will facilitate targeted snail control measures that complement drug treatment in the control of schistosomiasis in the country.
- MeSH
- Biomphalaria * parazitologie MeSH
- Bulinus parazitologie MeSH
- hlemýždi parazitologie MeSH
- lidé MeSH
- Schistosoma fyziologie MeSH
- schistosomóza * epidemiologie veterinární MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- systematický přehled MeSH
- Geografické názvy
- Konžská demokratická republika MeSH
Bird schistosomes have been in focus as causative agents of cercarial dermatitis of humans in the last years; however, our knowledge of their species spectrum and intermediate host specificity is still insufficient. Our study focused on bird schistosomes developing in planorbid snails that have been less studied so far. From 2001 to 2010, cercariae of bird schistosomes were found in four snail species (Gyraulus albus, Segmentina nitida, Anisus vortex and Planorbis planorbis) from seven localities in the Czech Republic. Based on morphology and results of molecular analysis, the isolates found belong to at least six species. Five of them are probably undescribed species, and one species appears to be identical with Gigantobilharzia vittensis Reimer, 1963 (syn. G. suebica Dönges, 1964). The finding from S. nitida represents the first report of a bird schistosome from this snail.
- MeSH
- cerkárie MeSH
- dermatitida parazitologie MeSH
- DNA helmintů chemie genetika MeSH
- fylogeneze MeSH
- hlemýždi parazitologie MeSH
- hostitelská specificita MeSH
- infestace ektoparazity parazitologie přenos veterinární MeSH
- kachny MeSH
- kur domácí MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- nemoci ptáků parazitologie přenos MeSH
- pěnkavovití MeSH
- ribozomální DNA chemie genetika MeSH
- Schistosoma anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- schistosomóza parazitologie přenos veterinární MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Under laboratory conditions, the freshwater snails Galba truncatula Müll.), Radix peregra (Müll.) and Planorbarius corneus (L.) have been successfully infected with the first stage larvae of the protostrongylid nematode Varestrongylus sagittatus (Mueller, 1890) Dougherty, 1945. The net rate of the infection (mean number of larvae per snail examined - l/s) was 6.2 l/s in R. peregra and 3.5 l/s in P. corneus. G. truncatula was susceptible to the infection too (36.3 l/s). However, this result can be considered as pilot only, because of the low number of the specimens of this species examined. At 25 degrees C 50% of V. sagittatus larvae reached the 3-rd stage of development by 12.5 days post infection (DPI) in R. peregra and by 17.8 DPI in P. corneus. It was confirmed that the snail species of the Basommatophora that were studied can act as intermediate hosts of the nematode V. sagittatus under laboratory conditions.
A survey of the larval stages (cercariae and metacercariae) of trematodes (Digenea) found in planorbid snails in Central Europe (Austria, Czech Republic, south-east Germany, Hungary, Poland and the Slovak Republic) is presented based on a study of 7,628 snails of 12 species examined between 1998-2006. A total of 34 trematode larval stages, comprising cercariae of 28 species and metacercariae of seven species (one species occurred both as cercaria and metacercaria) of nine families were found in 898 (11.5%) snails of eight species. The dominant cercariae were those belonging to the Rubenstrema exasperatum (Rudolphi, 1819)/Neoglyphe locellus (Kossack, 1910) species complex, Tylodelphys excavata (Rudolphi, 1803) and Echinostoma spiniferum (La Valette, 1855) sensu Nasincová (1992), all from Planorbarius corneus (Linnaeus). Almost the same spectrum of cercariae of the families Echinostomatidae, Plagiorchiidae and Omphalometridae was found in the present study as in previous reports; however, a considerably lower spectrum of cercariae of the families Diplostomidae and Strigeidae was recorded. The most frequent metacercariae were those of Echinoparyphium aconiatum Dietz, 1909, Neoglyphe locellus and Moliniella anceps (Molin, 1859), all occurring mainly in P. corneus. The most heavily infected snail species was P. corneus, followed by Planorbis planorbis (Linnaeus) and Segmentina nitida (Müller). The widest spectrum of trematode species was found in P. planorbis and P. corneus. Forty-two cercariae identified to the species level belonging to 15 families, plus an additional 43 taxa recorded under generic or provisional names, were reported from 11 species of planorbids in previous studies carried out in Central Europe. However, the actual number of trematode species occurring in the planorbid snails is probably much lower, because many, if not most, larval stages reported under provisional names or unidentified to the species level may be conspecific with identified adult forms. A key to the cercariae and metacercariae recorded from planorbids in Central Europe, together with illustrations of those species encountered most frequently in the field, is provided to facilitate identification.
- MeSH
- druhová specificita MeSH
- financování organizované MeSH
- hlemýždi parazitologie MeSH
- larva anatomie a histologie MeSH
- Trematoda anatomie a histologie izolace a purifikace klasifikace MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Geografické názvy
- Evropa MeSH
The discovery that mammalian neutrophils generate extracellular chromatin fibers that entrap/kill bacteria supported a new paradigm for innate immunity in animals. Similar findings in other models across diverse taxa have led to the hypothesis that the phenomenon is ancient and evolutionary conserved. Here, using a variety of synthetic (e.g. peptidoglycan) and biological (e.g. trematode larvae) components to investigate extracellular trap-like (ET-like) fiber production in vitro by haemocytes of Lymnaea stagnalis, Radix lagotis and Planorbarius corneus snails, ET-like fibers were rarely observed. We suggest, therefore, that ET-like fibers play a marginal role in defence of these snail species and thus the fiber production may not be a critical process underpinning immunity in all invertebrate species.
- MeSH
- antigeny helmintové imunologie MeSH
- biologická evoluce MeSH
- extracelulární pasti * MeSH
- hemocyty imunologie MeSH
- hlemýždi imunologie MeSH
- infekce červy třídy Trematoda imunologie MeSH
- kultivované buňky MeSH
- larva MeSH
- neutrofily imunologie MeSH
- peptidoglykan imunologie MeSH
- přirozená imunita MeSH
- savci imunologie MeSH
- Trematoda fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Freshwater pulmonate snails from three locations in Lake Furesø north of Copenhagen were screened for infection with furcocercariae (by shedding in the laboratory) and recovered parasite larvae were diagnosed by molecular methods (by performing PCR of rDNA and sequencing the internal transcribed spacer [ITS] region). Overall prevalence of infection in snails was 2%. Recovered cercariae from Lymnaea stagnalis (Linnaeus) were diagnosed as Diplostomum pseudospathaceum Niewiadomska, 1984 (prevalence 4%) and cercariae from Radix balthica (Linnaeus) as D. mergi (Dubois, 1932) (prevalence 2%). Pathogen-free rainbow trout were then exposed to isolated cercariae and infection success and site location of metacercariae in these fish were determined. Infection experiments confirmed that both species could infect rainbow trout with the eye lens as infection site for the metacercarial stage although infection success differed. Combination of molecular and biological assays may contribute to improvement of our knowledge on diagnosis, distribution and biology of diplostomids in fish.
- MeSH
- ekologie MeSH
- fylogeneze MeSH
- hlemýždi parazitologie MeSH
- infekce červy třídy Trematoda parazitologie přenos veterinární MeSH
- jezera parazitologie MeSH
- metacerkárie MeSH
- mezerníky ribozomální DNA chemie genetika MeSH
- molekulární sekvence - údaje MeSH
- nemoci ryb parazitologie přenos MeSH
- Oncorhynchus mykiss parazitologie MeSH
- organismy bez specifických patogenů MeSH
- polymerázová řetězová reakce veterinární MeSH
- roční období MeSH
- ryby MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA veterinární MeSH
- sladká voda parazitologie MeSH
- Trematoda genetika izolace a purifikace fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Dánsko MeSH
