Publications by authors named "Tina Walters"

Bloom-forming gelatinous zooplankton occur circumglobally and significantly influence the structure of pelagic marine food webs and biogeochemical cycling through interactions with microbial communities. During bloom conditions especially, gelatinous zooplankton are keystone taxa that help determine the fate of primary production, nutrient remineralization, and carbon export. Using the pelagic tunicate Dolioletta gegenbauri as a model system for gelatinous zooplankton, we carried out a laboratory-based feeding experiment to investigate the potential ecosystem impacts of doliolid gut microbiomes and microbial communities associated with doliolid faecal pellets and the surrounding seawater.

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The study of invasive species often focuses on regions of recent introduction rather than native habitats. Understanding an invasive species in its natural environment, however, can provide important insights regarding the long-term outcome of invasions. In this study we investigated the diet of the invasive spiny water flea, , in two Austrian perialpine lakes, where it is native.

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The parasitic ciliate causing shrimp black gill (sBG) infections in penaeid shrimp has been identified. The sBG ciliate has a unique life cycle that includes an encysted divisional stage on the host's gills. The ciliature of the encysted trophont stage has been determined and is quite similar to that of the closely related apostomes Hyalophysa bradburyae and H.

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Gelatinous zooplanktons play a crucial role in ocean ecosystems. However, it is generally difficult to investigate their physiology, growth, fecundity, and trophic interactions primarily due to methodological challenges, including the ability to culture them. This is particularly true for the doliolid, Dolioletta gegenbauri.

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Black spot gill syndrome in the northern shrimp, Pandalus borealis, is caused by an apostome ciliate, Synophrya sp., found within the gill lamellae. Whole mount staining, thin section histology, electron microscopy, and molecular studies were carried out on infected gills.

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Gelatinous zooplankton play a crucial role in marine planktonic food webs. However, primarily due to methodological challenges, the in situ diet of zooplankton remains poorly investigated and little is known about their trophic interactions including feeding behaviour, prey selection and in situ feeding rates. This is particularly true for gelatinous zooplankton including the marine pelagic tunicate, Dolioletta gegenbauri.

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Increasingly, diseases of marine organisms are recognized as significant biotic factors affecting ecosystem health. However, the responsible disease agents are often unknown and the discovery and description of novel parasites most often rely on morphological descriptions made by highly trained specialists. Here, we describe a new approach for parasite discovery, utilizing denaturing high-performance liquid chromatography (DHPLC) reverse-phase ion-pairing technology.

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Recently, we described a novel denaturing high-performance liquid chromatography (DHPLC) approach useful for initial detection and identification of crustacean parasites. Because this approach utilizes general primers targeted to conserved regions of the 18S rRNA gene, a priori genetic sequence information on eukaryotic parasites is not required. This distinction provides a significant advantage over specifically targeted PCR assays that do not allow for the detection of unknown or unsuspected parasites.

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