Effects of pond water, sediment, and sediment extracts from minnesota and vermont, USA, on early development and metamorphosis of xenopus

Fort, Douglas J.; Propst, Timothy L.; Stover, Enos L.; Helgen, Judy C.; Levey, Rick B.; Gallagher, Kathryn; Burkhart, James G.

doi:10.1002/etc.5620181027

Cited by 55 publications

(42 citation statements)

References 38 publications

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“…16,37 These studies clearly demonstrate the presence of an extractable hormonally active agent. However, identification based on the differential presence of extractable compounds at affected and control sites omits compounds that depend on a threshold concentration or the tadpole being compromised.…”

Section: Possible Confounding Factorsmentioning

confidence: 83%

<title>Biosensor, ELISA, and frog embryo teratogenesis assay: Xenopus (FETAX) analysis of water associated with frog malformations in Minnesota</title>

et al. 2001

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Between 1995 and 1997 over 62% of the counties in Minnesota reported the presence of malformed frogs. While most sites have recently shown a decline in malformed frog populations, one site in northeastern Minnesota with no prior history of malformed frogs was recently discovered to contain > 67% malformed Rana pipiens (northern leopard frogs). As part of an effort to study the presence of hormonally active agents in fresh water sources, water samples were collected from lakes in Minnesota containing malformed frogs and analyzed for the presence of biologically active compounds using a novel evanescent field fluorometric biosensor and the frog embryo teratogenesis assay: Xenopus (FETAX) bioassay. The waveguide based biosensor developed by ThreeFold Sensors (TFS biosensor, Ann Arbor, MI) monitors the interaction between free human ER-α and an estrogen immobilized on a sensor fiber. Inhibition of the interaction reflects the presence of estrogenic compounds. The FETAX bioassay is a developmental assay, which measures teratogenicity, mortality, and inhibition of growth during the first 96 hours of organogenesis and thereby provides a universal screen for endocrine disruptors. TFS biosensor and FETAX screening of the water samples suggest a relationship between estrogenic activity, mineral supplementation, and the occurrence of malformed frogs.

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Section: Possible Confounding Factorsmentioning

confidence: 83%

<title>Biosensor, ELISA, and frog embryo teratogenesis assay: Xenopus (FETAX) analysis of water associated with frog malformations in Minnesota</title>

et al. 2001

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“…The declining or threatened status of many North American amphibian populations further emphasizes the importance of determining the factors responsible, as malformed amphibians may suffer reduced survivorship (Johnson et al 2001b). Potential causes under investigation include biotic agents such as parasite infection (Sessions and Ruth 1990, Johnson et al 1999, 2001a, Sessions et al 1999 and predation (Bohl 1997), and abiotic agents such as UV-B radiation (Ankley et al 1998, pesticide contamination (Ouellet et al 1997, Burkhart et al 1998, Fort et al 1999 [but see also Tietge et al 2000], Bridges 2000), and retinoid exposure Hoppe 1999, Degitz et al 2000). While all of these factors can cause malformations under laboratory conditions, efforts to connect them causally on a large scale with malformed amphibians in the wild have remained unsuccessful.…”

Section: Introductionmentioning

confidence: 99%

Parasite (Ribeiroia ondatrae) Infection Linked to Amphibian Malformations in the Western United States

Johnson¹,

Lunde²,

Thurman³

et al. 2002

Ecological Monographs

114

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Parasites and pathogens can influence the survivorship, behavior, and very structure of their host species. For example, experimental studies have shown that trematode parasites can cause high frequencies of severe limb malformations in amphibians. In a broad-scale field survey covering parts of California, Oregon, Washington, Idaho, and Montana, we examined relationships between the frequency and types of morphological abnormalities in amphibians and the abundance of trematode parasite infection, pH, concentrations of 61 pesticides, and levels of orthophosphate and total nitrate. We recorded severe malformations at frequencies ranging from 1% to 90% in nine amphibian species from 53 aquatic systems. Infection of larvae by the trematode Ribeiroia ondatrae was associated with, and functionally related to, higher frequencies of amphibian limb malformations than found in uninfected populations (Յ5%). Parasites were concentrated around the basal tissue of hind limbs in infected anurans, and malformations associated with infection included skin webbings, supernumerary limbs and digits, and missing or malformed hind limbs. In the absence of Ribeiroia, amphibian populations exhibited low (0-5%) frequencies of abnormalities involving missing digits or distal portions of a hind limb. Species were affected differentially by the parasite, and Ambystoma macrodactylum, Hyla regilla, Rana aurora, R. luteiventris, and Taricha torosa typically exhibited the highest frequencies of abnormalities. None of the water-quality variables measured was associated with malformed amphibians, but aquatic snail hosts (Planorbella spp.) were significant predictors of the presence and abundance of Ribeiroia infection. Morphological comparisons of adult specimens of Ribeiroia collected from different sites and raised in experimental definitive hosts suggested that all samples represented the same species-R. ondatrae. These field results, coupled with experimental research on the effects of Ribeiroia on amphibians, demonstrate that Ribeiroia infection is an important and widespread cause of amphibian limb malformations in the western United States. The relevance of trematode infection to declines of amphibian populations and the influence of habitat modification on the pathology and life cycle of Ribeiroia are emphasized as areas requiring further research.

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“…Potential causes of limb malformations reported in amphibians include biocide contamination (Ouellet et al 1997;Burkhart et al 1998;Fort et al 1999; but see Tietge et al 2000), retinoid mimics (Gardiner and Hoppe 1999), predation (Bohl 1997a), UV-B radiation (Ankley et al 1998), and trematode infection (Sessions and Ruth 1990;Sessions et al 1999;Johnson et al 1999Johnson et al 2 ). For the majority of affected populations, however, proximate causes of the malformations have not been identified.…”

Section: Introductionmentioning

confidence: 99%

Regular Articles / Articles RéguliersRibeiroia ondatrae (Trematoda: Digenea) infection induces severe limb malformations in western toads (Bufo boreas)

Johnson¹,

Lunde²,

Haight³

et al. 2001

Can. J. Zool.

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Widespread reports of malformed amphibians in North America have prompted investigations into the cause(s) and implications of the phenomenon. Recently, a trematode parasite (Ribeiroia ondatrae) was identified as the probable cause of hind-limb malformations in Pacific treefrogs (Hyla regilla) from California. We exposed a second anuran species, the western toad (Bufo boreas), to specific levels of R. ondatrae infection. In a dose-dependent manner, R. ondatrae infection induced high frequencies (40-85%) of severe limb malformations in surviving toads. Survivorship declined significantly with increasing parasite exposure, falling to 42% in the heaviest treatment. Larvae in control treatments exhibited normal development and low mortality levels. In contrast to previous experiments with R. ondatrae infection in treefrogs, cutaneous fusion was the predominant malformation among infected toads in all treatments. Infection also caused polymely (extra limbs; fore and hind), ectromely (missing limbs), polydactyly (extra digits), and a variety of additional limb malformations. Taken together, these results demonstrate that (i) the teratogenic effects of R. ondatrae are not limited to treefrogs, (ii) the spectrum of R. ondatrae-induced malformations is not confined to the hind limbs, and (iii) the frequency and composition of malformations resulting from infection may vary among amphibian species. Finally, we review historical reports of limb abnormalities in the genus Bufo and discuss established and proposed causative agents, with emphasis on trematode infection and predation.Résumé : Les malformations chez les amphibiens sont de plus en plus signalées en Amérique du Nord; nous avons cherché à déterminer les causes et les conséquences de ce phénomène. Récemment, le trématode parasite (Ribeiroia ondatrae) a été reconnu comme la cause probable des malformations des membres postérieurs chez la Rainette du Pacifique (Hyla regilla) en Californie. Nous avons soumis une seconde espèce d'anoure, le Crapaud de l'ouest (Bufo boreas), à des infections de gravités diverses de R. ondatrae. Les infections de R. ondatrae entraînent des fréquences élevées (40-85 %) de malformations sérieuses des membres en fonction de la dose administrée chez les crapauds survivants. La survie diminue significativement à mesure qu'augmente l'exposition aux parasites, jusqu'à 42 % à la suite des traitements les plus sévères. Chez les larves des groupes témoins, le développement est normal et la mortalité est faible. Contrairement aux résultats d'expériences antérieures sur les rainettes, ici c'est la fusion cutanée qui constitue la principale malformation chez les crapauds infectés, à la suite de tous les traitements. Les infections sont aussi à l'origine de polymélies (membres surnuméraires, antérieurs et postérieurs), d'ectromélies (membres manquants), de polydactilies (doigts surnuméraires) et d'autres malformations des membres. Considérés dans leur ensemble, ces résultats démontrent que (i) les effets tératogènes de R. ondatrae ne sont pas restreint...

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Effects of pond water, sediment, and sediment extracts from minnesota and vermont, USA, on early development and metamorphosis of xenopus

Cited by 55 publications

References 38 publications

<title>Biosensor, ELISA, and frog embryo teratogenesis assay: Xenopus (FETAX) analysis of water associated with frog malformations in Minnesota</title>

<title>Biosensor, ELISA, and frog embryo teratogenesis assay: Xenopus (FETAX) analysis of water associated with frog malformations in Minnesota</title>

Parasite (Ribeiroia ondatrae) Infection Linked to Amphibian Malformations in the Western United States

<B>Regular Articles / Articles Réguliers</B><P><i>Ribeiroia ondatrae</i> (Trematoda: Digenea) infection induces severe limb malformations in western toads (<i>Bufo boreas</i>)

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