Amphibian populations are decreasing worldwide, and pollution is a contributing factor. Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants known to exert immunotoxicity. To assess impacts of PCBs on frogs, we exposed Lithobates pipiens tadpoles to a diet of PCB-126 (0-5 ng PCB-126/g wet food) through metamorphic climax. Postmetamorphic frogs were immunized with keyhole limpet hemocyanin (KLH); then production of KLH-specific IgY, as well as total IgY and IgM, was measured (Trial I). A second larval study (0 and 7.3 ng PCB-126/g wet food) was performed to investigate whether PCB altered antigenic responses in prometamorphic tadpoles (Gosner Stage 36-39), and to measure the innate immune response of postmetamorphic frogs (Trial II). After larval PCB-126 exposure, both KLH-specific IgY levels and complement activity were reduced. Because postmetamorphic frogs carried a body burden of PCB-126 (2.4 ng/g or less), we wanted to determine whether the effect on immune response was due to larval exposure or to the resulting body burden as frogs. To test this, we reared tadpoles under control conditions (no PCB), and limited PCB exposure to postmetamorphosis only by injecting 2-week-old frogs with 10 ng PCB-126/g (Trial III). The resulting body burden (3.4 ng/g) was similar to that of frogs in Trial I, but we no longer detected suppression of KLH-specific IgY or hemolytic activity. These results suggest life-stage-specific immune responses; however, because we administered PCB-126 differently between trials, it is premature to conclude that these differences are intrinsically life stage dependent, and further study is warranted. Regardless, our study demonstrated a long-lasting effect of larval PCB-126 exposure that persisted through metamorphosis and suppressed frog immunity. Environ Toxicol Chem 2022;41:81-94. © 2021 SETAC.

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.5233DOI Listing

Publication Analysis

Top Keywords

postmetamorphic frogs
12
klh-specific igy
12
body burden
12
larval exposure
8
frogs
8
lithobates pipiens
8
wet food
8
immune response
8
frogs trial
8
larval pcb-126
8

Similar Publications

It has frequently been hypothesized that among-individual variation in behavior and physiology will correlate with life history traits, yet the nature of these correlations can vary. Such variability may arise from plasticity in trait development, which can amplify or attenuate trait correlations across different environments. Using the Mexican spadefoot toad (Spea multiplicata), we tested whether relationships between larval growth rate and post-metamorphic behavior or physiology are influenced by a key mediator of developmental plasticity: larval diet type.

View Article and Find Full Text PDF

Myiasis by the Toad Fly (Lucilia bufonivora; Calliphoidae) in Amphibians in Montana, USA.

J Wildl Dis

September 2024

W. A. Franke College of Forestry and Conservation, Forestry 110, 32 Campus Drive, University of Montana, Missoula, Montana 59812, USA.

Toad flies in the genus Lucilia (previously referred to as Bufolucilia spp.) parasitize and cause myiasis in several amphibian species in North America. From 2019 to 2022, we documented Lucilia bufonivora infections in post-metamorphic western toads (Anaxyrus boreas) during amphibian surveys in four wetlands in Glacier National Park, Montana, US.

View Article and Find Full Text PDF

In all vertebrates, maintaining trunk posture primarily depends on descending commands originating from brainstem vestibulospinal nuclei. Despite being broadly outlined across species, the detailed anatomical and operational structure of these vestibulospinal networks remains poorly understood. frogs have previously served as an excellent model for exploring such anatomical and functional aspects in relation to the animal's behavioral requirements.

View Article and Find Full Text PDF

In contrast to other S100 protein members, the function of S100 calcium-binding protein Z (S100Z) remains largely uncharacterized. It is expressed in the olfactory epithelium of fish, and it is closely associated with the vomeronasal organ (VNO) in mammals. In this study, we analyzed the expression pattern of S100Z in the olfactory system of the anuran amphibian Xenopus laevis.

View Article and Find Full Text PDF

Ontogeny of immunity and potential implications for co-infection.

Philos Trans R Soc Lond B Biol Sci

July 2023

Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46656, USA.

Immunity changes through ontogeny and can mediate facilitative and inhibitory interactions among co-infecting parasite species. In amphibians, most immune memory is not carried through metamorphosis, leading to variation in the complexity of immune responses across life stages. To test if the ontogeny of host immunity might drive interactions among co-infecting parasites, we simultaneously exposed Cuban treefrogs () to a fungus (, Bd) and a nematode () at tadpole, metamorphic and post-metamorphic life stages.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!