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Arkin R, Márquez R. The effects of preformed vitamin A and provitamin A carotenoid supplementation on tadpoles of the poison frog Phyllobates vittatus. Zoo Biol 2024; 43:169-177. [PMID: 38284487 DOI: 10.1002/zoo.21816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 12/08/2023] [Accepted: 01/02/2024] [Indexed: 01/30/2024]
Abstract
Understanding the nutritional requirements of captive animals is necessary for proper animal husbandry, however, the specific dietary requirements for many amphibian species commonly kept in captivity are unknown. Like most vertebrates, frogs cannot synthesize carotenoids and must therefore obtain these essential nutrients through diet. It is unclear if amphibians can cleave provitamin A carotenoids to form vitamin A metabolically within the body, so common practice is to supplement their captive diets with both preformed vitamin A and provitamin A carotenoids. We carried out a feeding experiment in tadpoles of Phyllobates vittatus, a commonly kept poison frog species, to test the effects of supplementing a fish flake diet with a provitamin A carotenoid (2.5 mg/g β-carotene) and vitamin A (0.033-0.066 µg/mL retinyl acetate), both individually and in combination. Contrary to our expectations, supplementation had either no effect or adverse effects on tadpole growth and survivorship. Tadpoles reared under supplemented diets with vitamin A showed higher mortality rates, coupled with symptoms of hypervitaminosis A. Survivors had a smaller body size and mass at metamorphosis. β-carotene supplementation alone had no detectable effect. The vitamin A and β-carotene levels in our supplemented diet have been shown to be harmless or benefit tadpoles of other species, yet our results indicate that adding these amounts to what is found in a generalist fish flake mix can have detrimental effects on P. vittatus tadpoles. More broadly, this study highlights the importance of creating husbandry guidelines based on the specific physiological needs of the species (or species groups) being kept in captivity, rather than general ones for all amphibians, as is often done.
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Affiliation(s)
- Rachel Arkin
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Roberto Márquez
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
- Michigan Society of Fellows, University of Michigan, Ann Arbor, Michigan, USA
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2
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Walton SJ, Silla AJ, Endler JA, Byrne PG. Does dietary β-carotene influence ontogenetic colour change in the southern corroboree frog? J Exp Biol 2021; 224:273479. [PMID: 34694382 DOI: 10.1242/jeb.243182] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/19/2021] [Indexed: 12/21/2022]
Abstract
Ontogenetic colour change occurs in a diversity of vertebrate taxa and may be closely linked to dietary changes throughout development. In various species, red, orange and yellow colouration can be enhanced by the consumption of carotenoids. However, a paucity of long-term dietary manipulation studies means that little is known of the role of individual carotenoid compounds in ontogenetic colour change. We know even less about the influence of individual compounds at different doses (dose effects). The present study aimed to use a large dietary manipulation experiment to investigate the effect of dietary β-carotene supplementation on colouration in southern corroboree frogs (Pseudophryne corroboree) during early post-metamorphic development. Frogs were reared on four dietary treatments with four β-carotene concentrations (0, 1, 2 and 3 mg g-1), with frog colour measured every 8 weeks for 32 weeks. β-Carotene was not found to influence colouration at any dose. However, colouration was found to become more conspicuous over time, including in the control treatment. Moreover, all frogs expressed colour maximally at a similar point in development. These results imply that, for our study species, (1) β-carotene may contribute little or nothing to colouration, (2) frogs can manufacture their own colour, (3) colour development is a continual process and (4) there may have been selection for synchronised development of colour expression. We discuss the potential adaptive benefit of ontogenetic colour change in P. corroboree. More broadly, we draw attention to the potential for adaptive developmental synchrony in the expression of colouration in aposematic species.
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Affiliation(s)
- Sara J Walton
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Aimee J Silla
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - John A Endler
- Centre for Integrative Ecology, School of Life and Environmental Science, Deakin University, Geelong, VIC 3216, Australia
| | - Phillip G Byrne
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
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3
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Cabrera‐Guzmán E, Díaz‐Paniagua C, Gomez‐Mestre I. Differential effect of natural and pigment‐supplemented diets on larval development and phenotype of anurans. J Zool (1987) 2020. [DOI: 10.1111/jzo.12827] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E. Cabrera‐Guzmán
- Ecology Evolution and Development Group Department of Wetland Ecology Estación Biológica de Doñana CSIC Seville Spain
- Department of Integrative Biology Oklahoma State University Stillwater OK USA
| | - C. Díaz‐Paniagua
- Ecology Evolution and Development Group Department of Wetland Ecology Estación Biológica de Doñana CSIC Seville Spain
| | - I. Gomez‐Mestre
- Ecology Evolution and Development Group Department of Wetland Ecology Estación Biológica de Doñana CSIC Seville Spain
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4
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Battistoni M, Bacchetta R, Di Renzo F, Metruccio F, Menegola E. Effect of nano-encapsulation of β-carotene on Xenopus laevis embryos development (FETAX). Toxicol Rep 2020; 7:510-519. [PMID: 32346517 PMCID: PMC7182698 DOI: 10.1016/j.toxrep.2020.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/08/2020] [Accepted: 04/14/2020] [Indexed: 01/01/2023] Open
Abstract
Vitamin A plays a vital role during embryo development as most precursor of embryonic retinoic acid, a key morphogen during embryogenesis. Carotenoids, including β-carotene, are important vegetal source of Vitamin A and in contrast to teratogenic potential of animal-derived retinoids, β-carotene is usually considered freed from embryotoxic effects and supplements in pregnancy with β-carotene are suggested. The aim of the present work is to evaluate the effect of bulk and nano-encapsulated β-carotene on embryo development, by using the animal model Frog Embryo Teratogenesis Assay: Xenopus- FETAX. Xenopus laevis embryos were exposed from late gastrula till pharyngula (the phylotypic stage for vertebrates) to the concentrations of BULK β-carotene 150-3000 ng/mL and NANO β-carotene 0.75-30 ng/mL. At pharyngula stage, some embryos were processed for whole mount neural crest cell immunostaining, while others embryos were allowed to develop till tadpole for morphological and histological evaluation of neural crest cells-derived structures. In this model, the nano-encapsulated β-carotene induced specific malformations at craniofacial and eye level, while the bulk formulation only induced developmental delays. Finally, the applied alternative animal model resulted a rapid and sensitive screening method able to re-evaluate the teratogenic profile of nano-encapsulated micronutrients.
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Affiliation(s)
- Maria Battistoni
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Renato Bacchetta
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Francesca Di Renzo
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | | | - Elena Menegola
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
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5
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McInerney EP, Silla AJ, Byrne PG. Effect of carotenoid class and dose on the larval growth and development of the critically endangered southern corroboree frog. CONSERVATION PHYSIOLOGY 2019; 7:coz009. [PMID: 30906558 PMCID: PMC6425257 DOI: 10.1093/conphys/coz009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 01/31/2019] [Accepted: 02/26/2019] [Indexed: 06/09/2023]
Abstract
Dietary carotenoids are expected to improve vertebrate growth and development, though evidence for beneficial effects remains limited. One reason for this might be that few studies have directly compared the effects of carotenoids from different classes (carotenes versus xanthophylls) at more than one dose. Here, we tested the effect of two doses of dietary β-carotene and lutein (representing two different carotenoid classes) on the growth and development of larval southern corroboree frogs (Pseudophryne corroboree). Individuals were supplemented with either β-carotene or lutein at one of two doses (0.1 mg g-1, 1 mg g-1), or given a diet without carotenoids (control). Each dietary treatment included 36 replicate individuals, and individuals remained on the same diet until metamorphosis (25-39 weeks). We measured larval survival, larval growth (body length), time to metamorphosis, metamorphic body size (mass and SVL), and body condition. Lutein had no detectable effect on larval growth and development. However, larvae receiving a high dose (1 mg g-1) of β-carotene metamorphosed significantly faster than all other dietary treatments, despite no significant differences in growth rate. This result indicates that β-carotene supplementation in P. corroboree has positive effects on development independent of growth effects. Our study provides new evidence for differential effects of carotenoid class and dose on vertebrate development. From a conservation perspective, our findings are expected to assist with the recovery of P. corroboree by expediting the generation of frogs required for the maintenance of captive insurance colonies, or the provision of frogs for release. More broadly, our study highlights the potential for dietary manipulation to assist with the ex situ management of threatened amphibian species worldwide.
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Affiliation(s)
- Emma P McInerney
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
| | - Aimee J Silla
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
| | - Phillip G Byrne
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
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Szuroczki D, Koprivnikar J, Baker R. Effects of dietary antioxidants and environmental stressors on immune function and condition in Lithobates (Rana) sylvaticus. Comp Biochem Physiol A Mol Integr Physiol 2019; 229:25-32. [DOI: 10.1016/j.cbpa.2018.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/29/2022]
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Keogh LM, Silla AJ, McFadden MS, Byrne PG. Dose and life stage-dependent effects of dietary beta-carotene supplementation on the growth and development of the Booroolong frog. CONSERVATION PHYSIOLOGY 2018; 6:coy052. [PMID: 30254750 PMCID: PMC6144775 DOI: 10.1093/conphys/coy052] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/17/2018] [Accepted: 08/28/2018] [Indexed: 05/08/2023]
Abstract
Carotenoids are known for their antioxidant capacity and are considered to play an important role in vertebrate growth and development. However, evidence for their beneficial effects remains limited, possibly because very few studies have tested for dose effects across different life stages. The present study investigated the effect of various doses of dietary beta-carotene supplements on the growth and development of larval and post-metamorphic Booroolong frogs (Litoria booroolongensis). Larval and post-metamorphic basal diets (containing 0.015 and 0.005 mg g-1 total carotenoids, respectively) were supplemented with beta-carotene at one of four concentrations: 0 mg g-1, 0.1 mg g-1, 1 mg g-1 and 10 mg g-1. Each treatment included 72 replicate individuals, and individuals remained on the same diet treatment over both life stages (spanning 53 experimental weeks). Our results show that larvae receiving an intermediate (1 mg g-1) beta-carotene supplement dose grew faster than unsupplemented larvae (0 mg g-1), and metamorphosed earlier. After metamorphosis, there was no effect of the lowest supplement dose (0.1 mg g-1) on growth and development. However, juveniles fed the highest supplement dose (10 mg g-1) displayed significantly smaller body mass and lower body condition, compared to all other supplement doses, from 4-months through to sexual maturity (7-months). These findings indicate that beta-carotene supplementation has positive effects on growth and development, but only at intermediate doses, and only in the larval life stage. This knowledge may assist with amphibian conservation by expediting the rate that metamorphs can be generated in captive breeding programmes. More broadly, this is the first study to demonstrate both dose and life stage-dependent effects of dietary beta-carotene supplementation on vertebrate growth and development.
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Affiliation(s)
- Leesa M Keogh
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
| | - Aimee J Silla
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
| | - Michael S McFadden
- Herpetofauna Department, Taronga Conservation Society Australia, Mosman, NSW, Australia
| | - Phillip G Byrne
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, NSW, Australia
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8
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Giraudeau M, Bonzom JM, Ducatez S, Beaugelin-Seiller K, Deviche P, Lengagne T, Cavalie I, Camilleri V, Adam-Guillermin C, McGraw KJ. Carotenoid distribution in wild Japanese tree frogs (Hyla japonica) exposed to ionizing radiation in Fukushima. Sci Rep 2018; 8:7438. [PMID: 29743616 PMCID: PMC5943346 DOI: 10.1038/s41598-018-25495-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 04/03/2018] [Indexed: 12/28/2022] Open
Abstract
The nuclear accident in the Fukushima prefecture released a large amount of artificial radionuclides that might have short- and long-term biological effects on wildlife. Ionizing radiation can be a harmful source of reactive oxygen species, and previous studies have already shown reduced fitness effects in exposed animals in Chernobyl. Due to their potential health benefits, carotenoid pigments might be used by animals to limit detrimental effects of ionizing radiation exposure. Here, we examined concentrations of carotenoids in blood (i.e. a snapshot of levels in circulation), liver (endogenous carotenoid reserves), and the vocal sac skin (sexual signal) in relation to the total radiation dose rates absorbed by individual (TDR from 0.2 to 34 µGy/h) Japanese tree frogs (Hyla japonica). We found high within-site variability of TDRs, but no significant effects of the TDR on tissue carotenoid levels, suggesting that carotenoid distribution in amphibians might be less sensitive to ionizing radiation exposure than in other organisms or that the potential deleterious effects of radiation exposure might be less significant or more difficult to detect in Fukushima than in Chernobyl due to, among other things, differences in the abundance and mixture of each radionuclide.
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Affiliation(s)
- Mathieu Giraudeau
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA.
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK.
| | - Jean-Marc Bonzom
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint Paul Lez Durance, France.
| | - Simon Ducatez
- School of Biological Sciences A08, University of Sydney, Sydney, NSW 2006, Australia
| | - Karine Beaugelin-Seiller
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint Paul Lez Durance, France
| | - Pierre Deviche
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
| | - Thierry Lengagne
- Université de Lyon 1, CNRS, UMR 5023, Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés, Bât. Darwin C, F-69622, Villeurbanne Cedex, France
| | - Isabelle Cavalie
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint Paul Lez Durance, France
| | - Virginie Camilleri
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint Paul Lez Durance, France
| | - Christelle Adam-Guillermin
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SRTE/LECO, Cadarache, 13115, Saint Paul Lez Durance, France
| | - Kevin J McGraw
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
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Byrne PG, Silla AJ. Testing the effect of dietary carotenoids on larval survival, growth and development in the critically endangered southern corroboree frog. Zoo Biol 2017; 36:161-169. [PMID: 28198035 DOI: 10.1002/zoo.21352] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 01/09/2017] [Accepted: 01/17/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Phillip G. Byrne
- Centre for Sustainable Ecosystem SolutionsSchool of Biological SciencesUniversity of WollongongWollongongNew South WalesAustralia
| | - Aimee J. Silla
- Centre for Sustainable Ecosystem SolutionsSchool of Biological SciencesUniversity of WollongongWollongongNew South WalesAustralia
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10
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Edwards CL, Byrne PG, Harlow P, Silla AJ. Dietary Carotenoid Supplementation Enhances the Cutaneous Bacterial Communities of the Critically Endangered Southern Corroboree Frog (Pseudophryne corroboree). MICROBIAL ECOLOGY 2017; 73:435-444. [PMID: 27623966 DOI: 10.1007/s00248-016-0853-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/01/2016] [Indexed: 06/06/2023]
Abstract
The rapid spread of infectious disease has resulted in the decline of animal populations globally. Amphibians support a diversity of microbial symbionts on their skin surface that help to inhibit pathogen colonisation and reduce disease susceptibility and virulence. These cutaneous microbial communities represent an important component of amphibian immune defence, however, very little is known about the environmental factors that influence the cutaneous microbiome. Here, we characterise the cutaneous bacterial communities of a captive colony of the critically endangered Australian southern corroboree frog, Pseudophyrne corroboree, and examine the effect of dietary carotenoid supplementation on bacterial abundance, species richness and community composition. Individuals receiving a carotenoid-supplemented diet exhibited significantly higher bacterial abundance and species richness as well as an altered bacterial community composition compared to individuals that did not receive dietary carotenoids. Our findings suggest that dietary carotenoid supplementation enhances the cutaneous bacteria community of the southern corroboree frog and regulates the presence of bacteria species within the cutaneous microbiome. Our study is the second to demonstrate that carotenoid supplementation can improve amphibian cutaneous bacterial community dynamics, drawing attention to the possibility that dietary manipulation may assist with the ex situ management of endangered species and improve resilience to lethal pathogens such as Batrachochytrium dendrobatidis (Bd).
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Affiliation(s)
- Casey L Edwards
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Phillip G Byrne
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Peter Harlow
- Herpetofauna Division, Taronga Conservation Society Australia, Mosman, NSW, Australia
| | - Aimee J Silla
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Wollongong, NSW, 2522, Australia.
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Szuroczki D, Koprivnikar J, Baker RL. Dietary antioxidants enhance immunocompetence in larval amphibians. Comp Biochem Physiol A Mol Integr Physiol 2016; 201:182-188. [PMID: 27475300 DOI: 10.1016/j.cbpa.2016.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/22/2016] [Accepted: 07/24/2016] [Indexed: 12/20/2022]
Abstract
Dietary antioxidants have been shown to confer a variety of benefits through their ability to counter oxidative stress, including increased immunocompetence and reduced susceptibility to both infectious and non-infectious diseases. However, little is known about the effects of dietary antioxidants on immune function in larval amphibians, a group experiencing worldwide declines driven by factors that likely involve altered immunocompetence. We investigated the effects of dietary antioxidants (quercetin, vitamin E, and β-carotene) on two components of the immune system, as well as development and growth. Lithobates pipiens tadpoles fed diets with supplemental β-carotene or vitamin E exhibited an enhanced swelling response as measured with a phytohemagglutinin assay (PHA), but there was no induced antibody response. Effects were often dose-dependent, with higher antioxidant levels generally conferring stronger swelling that possibly corresponds to the innate immune response. Our results indicate that the antioxidant content of the larval amphibian diets not only had a detectable effect on their immune response capability, but also promoted tadpole growth (mass gain), although developmental stage was not affected. Given that many environmental perturbations may cause oxidative stress or reduce immunocompetence, it is critical to understand how nutrition may counter these effects.
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Affiliation(s)
- Dorina Szuroczki
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada.
| | - Janet Koprivnikar
- Department of Chemistry and Biology, Ryerson University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - Robert L Baker
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada
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Courtney Jones SK, Munn AJ, Penman TD, Byrne PG. Long-term changes in food availability mediate the effects of temperature on growth, development and survival in striped marsh frog larvae: implications for captive breeding programmes. CONSERVATION PHYSIOLOGY 2015; 3:cov029. [PMID: 27293714 PMCID: PMC4778449 DOI: 10.1093/conphys/cov029] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 05/20/2015] [Accepted: 05/24/2015] [Indexed: 05/25/2023]
Abstract
Food availability and temperature are known to trigger phenotypic change, but the interactive effects between these factors are only beginning to be considered. The aim of this study was to examine the independent and interactive effects of long-term stochastic food availability and water temperature on larval survivorship, growth and development of the striped marsh frog, Limnodynastes peronii. Larval L. peronii were reared in conditions of either constant or stochastic food availability and in water at three different temperatures (18, 22 and 26°C), and effects on survival, growth and development were quantified. Over the experimental period, larval growth rate was highest and survivorship lowest at the warmest temperature. However, changes in food availability mediated the effects of temperature, with slower larval growth and higher survivorship in stochastic food availability treatments. Tadpoles in the stochastic food availability treatments did not reach metamorphosis during the experimental period, suggesting that developmental stasis may have been induced by food restriction. Overall, these results demonstrate that changes in food availability alter the effects of water temperature on survival, growth and development. From an applied perspective, understanding how environmental factors interact to cause phenotypic change may assist with amphibian conservation by improving the number of tadpoles generated in captive breeding programmes.
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Affiliation(s)
- Stephanie K. Courtney Jones
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Adam J. Munn
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Trent D. Penman
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
- School of Ecosystem and Forest Science, University of Melbourne, Creswick, VIC 3363, Australia
| | - Phillip G. Byrne
- Institute for Conservation Biology and Environmental Management, School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
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