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Buss N, Hua J. Host exposure to a common pollutant can influence diversity-disease relationships. J Anim Ecol 2023; 92:2151-2162. [PMID: 37587564 DOI: 10.1111/1365-2656.13988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 05/15/2023] [Indexed: 08/18/2023]
Abstract
Hosts and parasites are embedded in communities where species richness and composition can influence disease outcomes (diversity-disease relationships). The direction and magnitude of diversity-disease relationships are influenced by variation in competence (ability to support and transmit infections) of hosts in a community. However, host susceptibility to parasites, which mediates host competence, is not static and is influenced by environmental factors, including pollutants. Despite the role that pollutants can play in augmenting host susceptibility, how pollutants influence diversity-disease dynamics is not well understood. Using an amphibian-trematode model, we tested how NaCl influences diversity-disease dynamics. We predicted that NaCl exposure can alter relative susceptibility of host species to trematodes, leading to cascading effects on the diversity-disease relationship. To test these predictions, we exposed hosts to benign or NaCl environments and generated communities that differed in number and composition of host species. We exposed these communities to trematodes and measured disease outcomes at the community (total infections across all hosts within a community) and species levels (average number of infections per host species within a community). Host species differed in their relative susceptibility to trematodes when exposed to NaCl. Consequently, at the community level (total infections across all hosts within a community), we only detected diversity-disease relationships (dilution effects) in communities where hosts were exposed to NaCl. At the species level, disease outcomes (average number of infections/species) and whether multi-species communities supported lower number of infections relative to single-species communities depended on community composition. Notably, however, as with overall community infection, diversity-disease relationships only emerged when hosts were exposed to NaCl. Synthesis. Pollutants are ubiquitous in nature and can influence disease dynamics across a number of host-parasite systems. Here, we show that NaCl exposure can alter the relative susceptibility of host species to parasites, influencing the relationship between biodiversity and disease at both community and species levels. Collectively, our study contributes to the limited knowledge surrounding environmental mediators of host susceptibility and their influence on diversity-disease dynamics.
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Affiliation(s)
- Nicholas Buss
- Department of Biological Sciences, Binghamton University (SUNY), Binghamton, New York, USA
| | - Jessica Hua
- Department of Biological Sciences, Binghamton University (SUNY), Binghamton, New York, USA
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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2
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Park JK, Do Y. Current State of Conservation Physiology for Amphibians: Major Research Topics and Physiological Parameters. Animals (Basel) 2023; 13:3162. [PMID: 37893886 PMCID: PMC10603670 DOI: 10.3390/ani13203162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/07/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
Analysis of physiological responses can be used to assess population health, identify threat factors, and understand mechanisms of stress. In addition to this, conservation physiologists have sought to establish potential management strategies for environmental change and evaluate the effectiveness of conservation efforts. From past to present, the field of conservation physiology is developing in an increasingly broader context. In this review, we aim to categorize the topics covered in conservation physiology research on amphibians and present the measured physiological parameters to provide directions for future research on conservation physiology. Physiological responses of amphibians to environmental stressors are the most studied topic, but conservation physiological studies on metamorphosis, habitat loss and fragmentation, climate change, and conservation methods are relatively lacking. A number of physiological indices have been extracted to study amphibian conservation physiology, and the indices have varying strengths of correlation with each subject. Future research directions are suggested to develop a comprehensive monitoring method for amphibians, identify interactions among various stressors, establish physiological mechanisms for environmental factors, and quantify the effects of conservation activities on amphibian physiology.
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Affiliation(s)
| | - Yuno Do
- Department of Biological Sciences, Kongju National University, Gongju 32588, Republic of Korea;
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3
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Douglas AJ, Katzenback BA. The wood frog (Rana sylvatica): An emerging comparative model for anuran immunity and host-ranavirus interactions. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 147:104733. [PMID: 37550009 DOI: 10.1016/j.dci.2023.104733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 05/06/2023] [Accepted: 05/09/2023] [Indexed: 08/09/2023]
Abstract
The wood frog (Rana sylvatica) is widely distributed across North America and is the only amphibian found north of the Arctic Circle due to its remarkable ability to tolerate whole-body freezing. Recent mass mortalities attributable to Ranavirus spp. (family Iridoviridae) in wild juvenile wood frogs, coupled with the apparent high susceptibility of wood frogs to experimental infection with frog virus 3 (FV3), the type species of the Ranavirus genus, or FV3-like isolates underscore the serious threat ranaviruses poses to wood frog populations. Despite the ecological relevance and unique life history of wood frogs, our understanding of the wood frog immune system and antiviral response to ranaviral infections is in its infancy. Here we aim to (1) synthesize the limited knowledge of wood frog immune defences, (2) review recent progress in establishing the wood frog as a study system for ranavirus infection, and (3) highlight the future use of wood frogs as a model anuran to provide insight into the evolution of anuran immune systems and antiviral responses.
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Affiliation(s)
- Alexander J Douglas
- Department of Biology, University of Waterloo, Waterloo, Ontario, N2L3G1, Canada
| | - Barbara A Katzenback
- Department of Biology, University of Waterloo, Waterloo, Ontario, N2L3G1, Canada.
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4
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Ruthsatz K, Schwarz A, Gomez-Mestre I, Meyer R, Domscheit M, Bartels F, Schaeffer SM, Engelkes K. Life in plastic, it's not fantastic: Sublethal effects of polyethylene microplastics ingestion throughout amphibian metamorphosis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163779. [PMID: 37146798 DOI: 10.1016/j.scitotenv.2023.163779] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/11/2023] [Accepted: 04/23/2023] [Indexed: 05/07/2023]
Abstract
Microplastics (MP) are an abundant, long-lasting, and widespread type of environmental pollution that is of increasing concern as it might pose a serious threat to ecosystems and species. However, these threats are still largely unknown for amphibians. Here, we used the African clawed frog (Xenopus laevis) as a model species to investigate whether polyethylene MP ingestion affects amphibian growth and development and leads to metabolic changes across two consecutive life stages (larvae and juveniles). Furthermore, we examined whether MP effects were more pronounced at higher rearing temperatures. Larval growth, development, and body condition were recorded, and standard metabolic rate (SMR) and levels of stress hormone (corticosterone, CORT) were measured. We determined variation in size, morphology, and hepatosomatic index in juveniles to identify any potential consequences of MP ingestion across metamorphosis. In both life stages, MP accumulation in the body was assessed. MP ingestion was found to result in sublethal effects on larval growth, development, and metabolism, to lead to allometric carry-over effects on juvenile morphology, and to accumulate in the specimens at both life stages. In larvae, SMR and developmental rate increased in response to MP ingestion; there additionally was a significant interaction of MP ingestion and temperature on development. CORT levels were higher in larvae that ingested MP, except at higher temperature. In juveniles, body was wider, and extremities were longer in animals exposed to MP during the larval stage; a high rearing temperature in combination with MP ingestion counteracted this effect. Our results provide first insights into the effects of MP on amphibians throughout metamorphosis and demonstrate that juvenile amphibians may act as a pathway for MP from freshwater to terrestrial environments. To allow for generalizations across amphibian species, future experiments need to consider the field prevalence and abundance of different MP in amphibians at various life stages.
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Affiliation(s)
- Katharina Ruthsatz
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany.
| | - Anja Schwarz
- Institute of Geosystems and Bioindication, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
| | - Ivan Gomez-Mestre
- Ecology, Evolution, and Development Group, Department Ecology and Evolution, Doñana Biological Station, CSIC, 41092 Seville, Spain
| | - Ruth Meyer
- Institute of Geosystems and Bioindication, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
| | - Marie Domscheit
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
| | - Fabian Bartels
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
| | - Sarah-Maria Schaeffer
- Institute of Geosystems and Bioindication, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany
| | - Karolin Engelkes
- Leibniz Institute for the Analysis of Biodiversity Change, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany; Institute of Evolutionary Biology and Ecology, University of Bonn, An der Immenburg 1, 53121 Bonn, Germany
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5
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Svinin AO, Chikhlyaev IV, Bashinskiy IW, Osipov VV, Neymark LA, Ivanov AY, Stoyko TG, Chernigova PI, Ibrogimova PK, Litvinchuk SN, Ermakov OA. Diversity of trematodes from the amphibian anomaly P hotspot: Role of planorbid snails. PLoS One 2023; 18:e0281740. [PMID: 36989233 PMCID: PMC10057761 DOI: 10.1371/journal.pone.0281740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/30/2023] [Indexed: 03/30/2023] Open
Abstract
Trematode infection of the second intermediate hosts can lead to changes in their fitness and, as a result, a change in the invasion rate of animal communities. It is especially pronounced during the invasion of parasite species that reduce activity due to the manipulation of hosts through the changes of their morphology and physiology. One of these cases is an anomaly P syndrome hotspot found in some populations of water frogs and toads in Europe caused by the trematode Strigea robusta metacercariae. The occurrence of pathogen and their participation in ecosystems are intrigues questions in the anomaly P phenomenon, as well as the role of planorbid snails that serve as the first intermediate hosts for many trematode species. Herein, we focused on trematodes spectra from planorbid snails and amphibians from the anomaly P hosts with the aim to undetected interactions between the pathways of parasites. Emerging cercariae of 6802 planorbid snails of dominant species (Planorbarius corneus, Planorbis planorbis, and Anisus spp.) were detected by both morphological and molecular methods in seven waterbodies in Privolzhskaya Lesostep Nature Reserve (Russia). A total of 95 sequences of 18 species were received, and 48 sequences were unique and did not present in any genetic databases. The 18 species of trematodes from snails and 14 species of trematodes from amphibian hosts (Pelophylax ridibundus; Ranidae; Anura) were detected. Three species (Echinostoma nasincovae, Tylodelphys circibuteonis and Australapatemon burti) was new for the trematode fauna of the Middle Volga River region and Russia as a whole. Eleven species of parasitic flatworms have amphibians in their life cycles and nine species used amphibians as metacercariae hosts: Echinostoma nasincovae, E. miyagawai, Echinoparyphium recurvatum, Tylodelphys circibuteonis, Neodiplostomum spathula, Paralepoderma cloacicola, Macrodera longicollis, Strigea robusta, and Strigea strigis. The occurrence of trematode species from planorbid mollusks and frogs were compared.
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Affiliation(s)
- Anton O Svinin
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, Tyumen, Russia
| | - Igor V Chikhlyaev
- Institute of Ecology of Volga River Basin, Samara Federal Research Scientific Center RAS, Togliatti, Russia
| | - Ivan W Bashinskiy
- Laboratory of Ecology of Aquatic Communities and Invasions, A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
| | - Vitaly V Osipov
- Privolzhskaya Lesosteppe State Nature Reserve, Penza, Russia
| | - Leonid A Neymark
- Institute of Ecology of Volga River Basin, Samara Federal Research Scientific Center RAS, Togliatti, Russia
| | | | - Tamara G Stoyko
- Department of Zoology and Ecology, Penza State University, Penza, Russia
| | - Polina I Chernigova
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, Tyumen, Russia
| | - Polina K Ibrogimova
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, Tyumen, Russia
| | | | - Oleg A Ermakov
- Department of Zoology and Ecology, Penza State University, Penza, Russia
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6
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Svinin AO, Ermakov OA, Litvinchuk SN. The incidence of the anomaly P syndrome in water frogs (Anura, Ranidae, Pelophylax) from the Middle Volga River (Russia). HERPETOZOA 2022. [DOI: 10.3897/herpetozoa.35.e95928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The anomaly P is a widespread morphological anomaly, which occurs in some groups of amphibians, caused by the trematode parasite Strigea robusta (Digenea: Strigeidae). This anomaly has been previously recorded in water frogs of the genus Pelophylax and toads of the genera Bufo and Bufotes. The anomaly P includes symmetrical polydactyly cases as a mild attenuated form of the complex syndrome, which in severe cases includes strong deformations of hindlimbs and forelimbs. Strigea robusta has a complex 3-host life cycle using planorbid mollusks as the first intermediate hosts, amphibian larvae as the second intermediate hosts, and anatid birds as the definitive hosts. Herein, we described new records of the anomaly P syndrome in water frogs of the genus Pelophylax from the northeastern parts of their ranges. Symmetrical polydactyly (as a mild form of the anomaly P syndrome) was found in 30 individuals of three species of water frogs from seven localities: in 25 individuals of P. lessonae from four waterbodies, in four individuals of P. ridibundus from three waterbodies, and one individual of P. esculentus. In Gusevo pond, three individuals of P. lessonae with severe cases of the syndrome were found. This is the first record of the anomaly P in reliably identified hybridogenetic edible frogs (P. esculentus) that have been identified in nature. Additionally, we provided new data about the occurrence of the anomaly P and the prevalence of the trematode S. robusta in mollusks taken from two water bodies where anomalous water frogs were found.
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7
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Lech ME, Choi YJ, Lee LS, Sepúlveda MS, Hoverman JT. Effects of Per- and Polyfluoroalkyl Substance Mixtures on the Susceptibility of Larval American Bullfrogs to Parasites. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:15953-15959. [PMID: 36251391 DOI: 10.1021/acs.est.2c04574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants known to adversely affect health and development in many taxa. Although PFAS generally occur as mixtures in the environment, little is known about the effects of PFAS mixtures on organisms compared to single chemical exposures. Moreover, PFAS exposure in nature occurs alongside biotic factors such as parasitism. Even though host-parasite interactions are common in natural systems, there is little information about how PFAS affect these interactions. Here, we examined the effects of PFAS mixtures on the susceptibility of larval American bullfrogs (Rana catesbeiana) to echinostomes. Our PFAS treatments included perfluorooctanesulfonic acid (PFOS) at 4 and 10 ppb, two mixtures without PFOS as a component at 6 and 10 ppb total PFAS, and a mixture containing PFOS at 10 ppb total PFAS. We found that a 62-day PFAS exposure increased parasite loads by 42-100% in all treatments relative to the control. Additionally, we found that the singular exposure to PFOS increased parasite loads by ∼40% compared to a mixture containing PFOS suggesting antagonism among PFAS in mixtures. Our results highlight the need for further investigation into the effects of PFAS mixtures on organisms and how PFAS affect common ecological interactions.
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Affiliation(s)
- Melissa E Lech
- Forestry and Natural Resources, Purdue University, West Lafayette, Indiana47907, United States
| | - Youn Jeong Choi
- Department of Agronomy, Purdue University, West Lafayette, Indiana47907, United States
| | - Linda S Lee
- Department of Agronomy, Purdue University, West Lafayette, Indiana47907, United States
| | - Marisol S Sepúlveda
- Forestry and Natural Resources, Purdue University, West Lafayette, Indiana47907, United States
| | - Jason T Hoverman
- Forestry and Natural Resources, Purdue University, West Lafayette, Indiana47907, United States
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8
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Component Endoparasite Communities Mirror Life-History Specialization in Syntopic Reed Frogs (Hyperolius spp.). DIVERSITY 2021. [DOI: 10.3390/d13120669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Most of our knowledge on the processes structuring parasite communities in amphibians originate from temperate-zone taxa, whereas Afrotropical communities have been neglected so far. We found evidence that ecological fitting of the hosts and, probably, differential immune response may influence the variation in parasite species richness, prevalence, and infestation intensity of East African frogs Hyperolius kivuensis and H. viridiflavus. The most closely related host species share the same macrohabitat (that implies the same pool of potential parasites), but differ in microhabitat preference, so that a comparative analyses of syntopic and allopatric populations is expedient to reveal ecological fitting. We detected 11 parasite species (one annelid, four nematodes, five trematodes, one cestode) and two endocommensal species (protozoans). The component parasite communities included 4–5 helminth species in H. kivuensis and 6–8 in the more aquatic H. viridiflavus, supporting the hypothesis that trematode diversity increases with the amount of time spent in water. Five parasite species (Orneoascaris chrysanthemoides, Clinostomum chabaudi, an undetermined echinostomatid) and two protozoans (Nyctotheroides sp., and Protoopalina sp.) are shared among the syntopic amphibian populations. This finding indicates a similar susceptibility of these amphibians to infestation from the local parasite pool. Yet, the low prevalence of single- and multi-species infestations in H. kivuensis indicates that parasite clearing by its immune response is probably more effective and prominent than in H. viridiflavus. Therefore, H. viridiflavus suffered from significantly reduced short-term survival due to the infection. Thus, we conclude that the processes structuring component parasite communities in amphibians do not differ generally between temperate-zone and Afrotropical host species, but they do in the magnitude of ecological fitting.
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9
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Ruthsatz K, Dausmann KH, Paesler K, Babos P, Sabatino NM, Peck MA, Glos J. Shifts in sensitivity of amphibian metamorphosis to endocrine disruption: the common frog ( Rana temporaria) as a case study. CONSERVATION PHYSIOLOGY 2020; 8:coaa100. [PMID: 33343902 PMCID: PMC7735370 DOI: 10.1093/conphys/coaa100] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/28/2020] [Accepted: 11/09/2020] [Indexed: 06/01/2023]
Abstract
Effective conservation actions require knowledge on the sensitivity of species to pollution and other anthropogenic stressors. Many of these stressors are endocrine disruptors (EDs) that can impair the hypothalamus-pituitary-thyroid axis and thus alter thyroid hormone (TH) levels with physiological consequences to wildlife. Due to their specific habitat requirements, amphibians are often sentinels of environmental degradation. We investigated how altered TH levels affected the bioenergetics of growth and development (i.e. age, size, metabolism, cardiac function and energy stores) before, during and after metamorphosis in the European common frog (Rana temporaria). We also determined how ontogenetic stage affected susceptibility to endocrine disruption and estimated juvenile performance. TH levels significantly affected growth and energetics at all developmental stages. Tadpoles and froglets exposed to high TH levels were significantly younger, smaller and lighter at all stages compared to those in control and low TH groups, indicating increased developmental and reduced growth rates. Across all ontogenetic stages tested, physiological consequences were rapidly observed after exposure to EDs. High TH increased heart rate by an average of 86% and reduced energy stores (fat content) by 33% compared to controls. Effects of exposure were smallest after the completion of metamorphosis. Our results demonstrate that both morphological and physiological traits of the European common frog are strongly impacted by endocrine disruption and that ontogenetic stage modulates the sensitivity of this species to endocrine disruption. Since endocrine disruption during metamorphosis can impair the physiological stress response in later life stages, long-term studies examining carry-over effects will be an important contribution to the conservation physiology of amphibians.
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Affiliation(s)
- Katharina Ruthsatz
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
| | - Kathrin H Dausmann
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Katharina Paesler
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Patricia Babos
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Nikita M Sabatino
- Department of Life Sciences, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany
| | - Myron A Peck
- Institute of Marine Ecosystems and Fisheries Science, Universität Hamburg, Große Elbstraße 133, 22767 Hamburg, Germany
- Department of Coastal Systems, Royal Netherlands Institute for Sea Research, PO Box 59 1790, AB Den Burg, Netherlands
| | - Julian Glos
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
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10
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Buss N, Nelson KN, Hua J, Relyea RA. Effects of different roadway deicing salts on host-parasite interactions: The importance of salt type. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:115244. [PMID: 32688196 DOI: 10.1016/j.envpol.2020.115244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 05/27/2023]
Abstract
The application of roadway deicing salts is increasing the salinity of freshwater systems. Increased salinization from salts, such as NaCl, CaCl2 and MgCl2, can have direct, negative impacts on freshwater organisms at concentrations found in nature. Yet, our understanding of how these salts can indirectly impact freshwater organisms by altering important ecological interactions, such as those between hosts and their parasites, is limited. Using a larval amphibian and infectious free-living helminth (i.e. trematode) model, we examined whether exposure to environmentally relevant concentrations of NaCl, CaCl2 and MgCl2 1) influence trematode mortality; 2) alter amphibian-trematode interactions; and 3) alter larval amphibian activity (a behavior associated with parasite avoidance). We found that exposure to CaCl2 greatly reduced trematode survival across all Cl- concentrations (230, 500, 860 and 1000 mg Cl- L-1) while NaCl and MgCl2 had no effect. When both host and parasites were exposed to the salts, exposure to NaCl, but not MgCl2 or CaCl2, increased infection. The lack of effect of CaCl2 on infection was likely driven by CaCl2 reducing trematode survival. Exposure to NaCl increased infection at 500 mg Cl- L-1, but not 230 or 860 mg Cl- L-1. Increased infection was not due to salt exposure altering tadpole behavior. Our results suggest that NaCl can negatively impact amphibian populations indirectly by increasing trematode infections in tadpole hosts.
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Affiliation(s)
- Nicholas Buss
- Biological Sciences Department, Binghamton University (SUNY), Binghamton, NY, 13902, USA.
| | - Kiersten N Nelson
- Department of Biological Sciences, Rensselaer Polytechnic Institute, 110 8th St., Troy, NY, 12180, USA
| | - Jessica Hua
- Biological Sciences Department, Binghamton University (SUNY), Binghamton, NY, 13902, USA
| | - Rick A Relyea
- Department of Biological Sciences, Rensselaer Polytechnic Institute, 110 8th St., Troy, NY, 12180, USA
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11
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Jones JR, Steenrod CL, Marino JA. Effects of vertical position on trematode parasitism in larval anurans. Curr Zool 2020; 65:657-664. [PMID: 32440271 PMCID: PMC7233612 DOI: 10.1093/cz/zoz004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 02/02/2019] [Indexed: 11/27/2022] Open
Abstract
Spatial distributions of animals can affect interactions with their natural enemies, such as parasites, and thus have important implications for host–parasite dynamics. While spatial variation in infection risk has been explored in many systems at the landscape scale, less attention has been paid to spatial structure at smaller scales. Here, we explore a hypothesized relationship between a common spatial variable, vertical position, and risk of parasite infection in a model aquatic system, larval frogs (Rana) and trematode (Digenea) parasites. Vertical position is relevant to this system given evidence that the densities of snail first intermediate hosts, tadpole second intermediate hosts, and trematode infective stages can vary with depth. To test the effects of depth on infection risk of larval frogs by trematodes, we performed two enclosure experiments, one in the laboratory and one in the field, in which larval frogs in cages just below the water surface or near the bottom of the water column were exposed to parasites. Compared with near-surface cages, mean infection load (number of cysts) in tadpoles in near-bottom cages was 83% higher after 48-h exposures in the laboratory and 730% higher after 10-day exposures in the field. Our findings thus indicate that infection risk depends on depth, which may have adaptive significance, as tadpoles have previously been shown to change vertical position in response to parasite presence. These results motivate future work examining vertical variation in infection risk and may have broader implications for host–parasite dynamics and evolution of host and parasite behavior.
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Affiliation(s)
- Jacob R Jones
- Biology Department, Bradley University, Peoria, IL, USA
| | | | - John A Marino
- Biology Department, Bradley University, Peoria, IL, USA
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12
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Ruthsatz K, Dausmann KH, Reinhardt S, Robinson T, Sabatino NM, Peck MA, Glos J. Post-metamorphic carry-over effects of altered thyroid hormone level and developmental temperature: physiological plasticity and body condition at two life stages in Rana temporaria. J Comp Physiol B 2020; 190:297-315. [PMID: 32144506 DOI: 10.1007/s00360-020-01271-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 02/03/2020] [Accepted: 02/15/2020] [Indexed: 01/08/2023]
Abstract
Environmental stress induced by natural and anthropogenic processes including climate change may threaten the productivity of species and persistence of populations. Ectotherms can potentially cope with stressful conditions such as extremes in temperature by exhibiting physiological plasticity. Amphibian larvae experiencing stressful environments display altered thyroid hormone (TH) status with potential implications for physiological traits and acclimation capacity. We investigated how developmental temperature (Tdev) and altered TH levels (simulating proximate effects of environmental stress) influence the standard metabolic rate (SMR), body condition (BC), and thermal tolerance in metamorphic and post-metamorphic anuran larvae of the common frog (Rana temporaria) reared at five constant temperatures (14-28 °C). At metamorphosis, larvae that developed at higher temperatures had higher maximum thermal limits but narrower ranges in thermal tolerance. Mean CTmax was 37.63 °C ± 0.14 (low TH), 36.49 °C ± 0.31 (control), and 36.43 °C ± 0.68 (high TH) in larvae acclimated to different temperatures. Larvae were able to acclimate to higher Tdev by adjusting their thermal tolerance, but not their SMR, and this effect was not impaired by altered TH levels. BC was reduced by 80% (metamorphic) and by 85% (post-metamorphic) at highest Tdev. The effect of stressful larval conditions (i.e., different developmental temperatures and, to some extent, altered TH levels) on SMR and particularly on BC at the onset of metamorphosis was carried over to froglets at the end of metamorphic climax. This has far reaching consequences, since body condition at metamorphosis is known to determine metamorphic success and, thus, is indirectly linked to individual fitness in later life stages.
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Affiliation(s)
- Katharina Ruthsatz
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.
| | - Kathrin H Dausmann
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Steffen Reinhardt
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Tom Robinson
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Nikita M Sabatino
- Department of Life Sciences, Hamburg University of Applied Sciences, Ulmenliet 20, 21033, Hamburg, Germany
| | - Myron A Peck
- Institute of Hydrobiology and Fisheries Science, University of Hamburg, Olbersweg 24, 22767, Hamburg, Germany
| | - Julian Glos
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
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13
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Robinson SA, Gavel MJ, Richardson SD, Chlebak RJ, Milotic D, Koprivnikar J, Forbes MR. Sub-chronic exposure to a neonicotinoid does not affect susceptibility of larval leopard frogs to infection by trematode parasites, via either depressed cercarial performance or host immunity. Parasitol Res 2019; 118:2621-2633. [PMID: 31300888 DOI: 10.1007/s00436-019-06385-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/24/2019] [Indexed: 12/26/2022]
Abstract
Little information is available on the effects of neonicotinoid insecticides on vertebrates. Previous work using amphibians found chronic exposure to some neonicotinoids had no detrimental effects on fitness-relevant traits. However, there is some evidence of more subtle effects of neonicotinoids on immune traits and evidence that other pesticides can suppress tadpole immunity resulting in elevated levels of parasitism in the exposed tadpoles. The objective of our study was to assess whether neonicotinoid exposure affected tadpole immunometrics and susceptibility to parasitic helminths. We assessed northern leopard frog tadpole (Lithobates pipiens) levels of parasitism and leukocyte profiles following exposure to environmentally relevant concentrations of clothianidin and free-living infective cercariae of a helminth parasite, an Echinostoma sp. trematode. When comparing tadpoles from controls to either 1 or 100 μg/L clothianidin treatments, we found similar measures of parasitism (i.e. prevalence, abundance and intensity of echinostome cysts) and similar leukocyte profiles. We also confirmed that clothianidin was not lethal for cercariae; however, slight reductions in swimming activity were detected at the lowest exposure concentration of 0.23 μg/L. Our results show that exposure to clothianidin during the larval amphibian stage does not affect leukocyte profiles or susceptibility to parasitism by larval trematodes in northern leopard frogs although other aspects such as length of host exposure require further study.
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Affiliation(s)
- Stacey A Robinson
- National Wildlife Research Centre, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, 1125 Colonel By Drive, Ottawa, ON, K1A 0H3, Canada.
| | - M J Gavel
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - S D Richardson
- National Wildlife Research Centre, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, 1125 Colonel By Drive, Ottawa, ON, K1A 0H3, Canada
| | - R J Chlebak
- National Wildlife Research Centre, Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, 1125 Colonel By Drive, Ottawa, ON, K1A 0H3, Canada.,Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - D Milotic
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, ON, M5B 2K3, Canada
| | - J Koprivnikar
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, ON, M5B 2K3, Canada
| | - M R Forbes
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
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14
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Ruthsatz K, Dausmann KH, Reinhardt S, Robinson T, Sabatino NM, Peck MA, Glos J. Endocrine Disruption Alters Developmental Energy Allocation and Performance in Rana temporaria. Integr Comp Biol 2019; 59:70-88. [PMID: 31095322 DOI: 10.1093/icb/icz041] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Environmental change exposes wildlife to a wide array of environmental stressors that arise from both anthropogenic and natural sources. Many environmental stressors with the ability to alter endocrine function are known as endocrine disruptors, which may impair the hypothalamus-pituitary-thyroid axis resulting in physiological consequences to wildlife. In this study, we investigated how the alteration of thyroid hormone (TH) levels due to exposure to the environmentally relevant endocrine disruptor sodium perchlorate (SP; inhibitory) and exogenous L-thyroxin (T4; stimulatory) affects metabolic costs and energy allocation during and after metamorphosis in a common amphibian (Rana temporaria). We further tested for possible carry-over effects of endocrine disruption during larval stage on juvenile performance. Energy allocated to development was negatively related to metabolic rate and thus, tadpoles exposed to T4 could allocate 24% less energy to development during metamorphic climax than control animals. Therefore, the energy available for metamorphosis was reduced in tadpoles with increased TH level by exposure to T4. We suggest that differences in metabolic rate caused by altered TH levels during metamorphic climax and energy allocation to maintenance costs might have contributed to a reduced energetic efficiency in tadpoles with high TH levels. Differences in size and energetics persisted beyond the metamorphic boundary and impacted on juvenile performance. Performance differences are mainly related to strong size-effects, as altered TH levels by exposure to T4 and SP significantly affected growth and developmental rate. Nevertheless, we assume that juvenile performance is influenced by a size-independent effect of achieved TH. Energetic efficiency varied between treatments due to differences in size allocation of internal macronutrient stores. Altered TH levels as caused by several environmental stressors lead to persisting effects on metamorphic traits and energetics and, thus, caused carry-over effects on performance of froglets. We demonstrate the mechanisms through which alterations in abiotic and biotic environmental factors can alter phenotypes at metamorphosis and reduce lifetime fitness in these and likely other amphibians.
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Affiliation(s)
- Katharina Ruthsatz
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Kathrin H Dausmann
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Steffen Reinhardt
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Tom Robinson
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Nikita M Sabatino
- Department of Life Sciences, Hamburg University of Applied Sciences, Ulmenliet 20, Hamburg, 21033, Germany
| | - Myron A Peck
- Institute of Hydrobiology and Fisheries Science, University of Hamburg, Olbersweg 24, Hamburg, 22767, Germany
| | - Julian Glos
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
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15
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Ruthsatz K, Dausmann KH, Peck MA, Drees C, Sabatino NM, Becker LI, Reese J, Hartmann L, Glos J. Thyroid hormone levels and temperature during development alter thermal tolerance and energetics of Xenopus laevis larvae. CONSERVATION PHYSIOLOGY 2018; 6:coy059. [PMID: 30464840 PMCID: PMC6240330 DOI: 10.1093/conphys/coy059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 08/29/2018] [Accepted: 10/16/2018] [Indexed: 06/02/2023]
Abstract
Environmental variation induced by natural and anthropogenic processes including climate change may threaten species by causing environmental stress. Anuran larvae experiencing environmental stress may display altered thyroid hormone (TH) status with potential implications for physiological traits. Therefore, any capacity to adapt to environmental changes through plastic responses provides a key to determining species vulnerability to environmental variation. We investigated whether developmental temperature (T dev), altered TH levels and whether the interactive effect of both affect standard metabolic rate (SMR), body condition (BC), survival and thermal tolerance in larvae of the African clawed frog (Xenopus laevis) reared at five temperatures with experimentally altered TH levels. At metamorphosis, SMR, BC and survival were significantly affected by T dev, TH status and their interaction with the latter often intensified impacts. Larvae developing at warmer temperatures exhibited significantly higher SMRs and BC was reduced at warm T dev and high TH levels suggesting decreased ability to acclimate to variation in temperature. Accordingly, tadpoles that developed at warm temperatures had higher maximum thermal limits but more narrow thermal tolerance windows. High and low TH levels decreased and increased upper thermal limits, respectively. Thus, when experiencing both warmer temperatures and environmental stress, larvae may be less able to compensate for changes in T dev. Our results demonstrate that physiological traits in larvae of X. laevis are strongly affected by increased TH levels and warmer temperatures. Altered TH levels and increasing T dev due to global change may result in a reduced capacity for physiological plasticity. This has far reaching consequences since the energetic requirement at the onset of metamorphosis is known to determine metamorphic success and thus, is indirectly linked to individual fitness in later life stages.
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Affiliation(s)
- Katharina Ruthsatz
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Kathrin H Dausmann
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Myron A Peck
- Institute of Hydrobiology and Fisheries Science, University of Hamburg, Olbersweg 24, Hamburg, Germany
| | - Claudia Drees
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Nikita M Sabatino
- Department of Life Sciences, Hamburg University of Applied Sciences, Ulmenliet 20, Hamburg, Germany
| | - Laura I Becker
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Janica Reese
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Lisa Hartmann
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
| | - Julian Glos
- Institute for Zoology, University of Hamburg, Martin-Luther-King-Platz 3, Hamburg, Germany
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