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Marchetti JR, Beard KH, Virgin EE, Lewis EL, Hess SC, Ki KC, Sermersheim LO, Furtado AP, French SS. Invasive frogs show persistent physiological differences to elevation and acclimate to colder temperatures. J Therm Biol 2023; 114:103590. [PMID: 37267784 DOI: 10.1016/j.jtherbio.2023.103590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/03/2023] [Accepted: 05/05/2023] [Indexed: 06/04/2023]
Abstract
The coqui frog (Eleutherodactylus coqui) was introduced to the island of Hawai'i in the 1980s and has spread across much of the island. Concern remains that this frog will continue to expand its range and invade higher elevation habitats where much of the island's endemic species are found. We determined whether coqui thermal tolerance and physiology change along Hawai'i's elevational gradients. We measured physiological responses using a short-term experiment to determine baseline tolerance and physiology by elevation, and a long-term experiment to determine the coqui's ability to acclimate to different temperatures. We collected frogs from low, medium, and high elevations. After both the short and long-term experiments, we measured critical thermal minimum (CTmin), blood glucose, oxidative stress, and corticosterone levels. CTmin was lower in high elevation frogs than low elevation frogs after the short acclimation experiment, signifying that they acclimate to local conditions. After the extended acclimation, CTmin was lower in frogs acclimated to cold temperatures compared to warm-acclimated frogs and no longer varied by elevation. Blood glucose levels were positively correlated with elevation even after the extended acclimation, suggesting glucose may also be related to lower temperatures. Oxidative stress was higher in females than males, and corticosterone was not significantly related to any predictor variables. The extended acclimation experiment showed that coquis can adjust their thermal tolerance to different temperatures over a 3-week period, suggesting the expansion of coqui into higher elevation habitats may still be possible, and they may not be as restricted by cold temperatures as previously thought.
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Affiliation(s)
- Jack R Marchetti
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Karen H Beard
- Department of Wildland Resources, Utah State University, Logan, UT, 84322, USA.
| | - Emily E Virgin
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Erin L Lewis
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Steven C Hess
- USDA APHIS-WS National Wildlife Research Center, Hawaii Field Station, Hilo, HI, 96720, USA
| | - Kwanho C Ki
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Layne O Sermersheim
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Adriana P Furtado
- Departamento de Ciências Animais, Universidade de Brasília, Distrito Federal, 70910900, Brazil
| | - Susannah S French
- Department of Biology and the Ecology Center, Utah State University, Logan, UT, 84322, USA
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2
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Niu Y, Zhang X, Men S, Storey KB, Chen Q. Integrated analysis of transcriptome and metabolome data reveals insights for molecular mechanisms in overwintering Tibetan frogs, Nanorana parkeri. Front Physiol 2023; 13:1104476. [PMID: 36699683 PMCID: PMC9868574 DOI: 10.3389/fphys.2022.1104476] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 12/27/2022] [Indexed: 01/11/2023] Open
Abstract
Nanorana parkeri (Anura, Dicroglossidae) is a unique frog living at high altitude on the Tibetan plateau where they must endure a long winter dormancy at low temperatures without feeding. Here, we presented a comprehensive transcriptomic and metabolomic analysis of liver tissue from summer-active versus overwintering N. parkeri, providing the first broad analysis of altered energy metabolism and gene expression in this frog species. We discovered that significantly up-regulated genes (2,397) in overwintering frogs mainly participated in signal transduction and immune responses, phagosome, endocytosis, lysosome, and autophagy, whereas 2,169 down-regulated genes were mainly involved in metabolic processes, such as oxidation-reduction process, amino acid metabolic process, fatty acid metabolic process, and TCA cycle. Moreover, 35 metabolites were shown to be differentially expressed, including 22 down-regulated and 13 up-regulated in winter. These included particularly notable reductions in the concentrations of most amino acids. These differentially expressed metabolites were mainly involved in amino acid biosynthesis and metabolism. To sum up, these findings suggest that gene expression and metabolic processes show adaptive regulation in overwintering N. parkeri, that contributes to maintaining homeostasis and enhancing protection in the hypometabolic state. This study has greatly expanded our understanding of the winter survival mechanisms in amphibians.
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Affiliation(s)
- Yonggang Niu
- Department of Life Sciences, Dezhou University, Dezhou, China,School of Life Sciences, Lanzhou University, Lanzhou, China,*Correspondence: Yonggang Niu, ; Qiang Chen,
| | - Xuejing Zhang
- School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Shengkang Men
- School of Life Sciences, Lanzhou University, Lanzhou, China
| | | | - Qiang Chen
- School of Life Sciences, Lanzhou University, Lanzhou, China,*Correspondence: Yonggang Niu, ; Qiang Chen,
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3
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Fieschi-Méric L, Van Leeuwen P, Hopkins K, Bournonville M, Denoël M, Lesbarrères D. Strong restructuration of skin microbiota during captivity challenges ex-situ conservation of amphibians. Front Microbiol 2023; 14:1111018. [PMID: 36891392 PMCID: PMC9986596 DOI: 10.3389/fmicb.2023.1111018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/31/2023] [Indexed: 02/22/2023] Open
Abstract
In response to the current worldwide amphibian extinction crisis, conservation instances have encouraged the establishment of ex-situ collections for endangered species. The resulting assurance populations are managed under strict biosecure protocols, often involving artificial cycles of temperature and humidity to induce active and overwintering phases, which likely affect the bacterial symbionts living on the amphibian skin. However, the skin microbiota is an important first line of defense against pathogens that can cause amphibian declines, such as the chytrid Batrachochytrium dendrobatidis (Bd). Determining whether current husbandry practices for assurance populations might deplete amphibians from their symbionts is therefore essential to conservation success. Here, we characterize the effect of the transitions from the wild to captivity, and between aquatic and overwintering phases, on the skin microbiota of two newt species. While our results confirm differential selectivity of skin microbiota between species, they underscore that captivity and phase-shifts similarly affect their community structure. More specifically, the translocation ex-situ is associated with rapid impoverishment, decrease in alpha diversity and strong species turnover of bacterial communities. Shifts between active and overwintering phases also cause changes in the diversity and composition of the microbiota, and on the prevalence of Bd-inhibitory phylotypes. Altogether, our results suggest that current husbandry practices strongly restructure the amphibian skin microbiota. Although it remains to be determined whether these changes are reversible or have deleterious effects on their hosts, we discuss methods to limit microbial diversity loss ex-situ and emphasize the importance of integrating bacterial communities to applied amphibian conservation.
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Affiliation(s)
- Léa Fieschi-Méric
- Laboratory of Ecology and Conservation of Amphibians (LECA), Freshwater and OCeanic science Unit of reSearch (FOCUS), Université de Liège, Liège, Belgium.,Biology Department, Laurentian University, Sudbury, ON, Canada
| | | | - Kevin Hopkins
- Institute of Zoology, Zoological Society of London (ZSL), London, United Kingdom
| | - Marie Bournonville
- Aquarium-Muséum de l'Université de Liège, Freshwater and OCeanic science Unit of reSearch (FOCUS), Liège, Belgium
| | - Mathieu Denoël
- Laboratory of Ecology and Conservation of Amphibians (LECA), Freshwater and OCeanic science Unit of reSearch (FOCUS), Université de Liège, Liège, Belgium
| | - David Lesbarrères
- Biology Department, Laurentian University, Sudbury, ON, Canada.,Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, ON, Canada
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4
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Recovering an endangered frog species through integrative reproductive technologies. Theriogenology 2022; 191:141-152. [DOI: 10.1016/j.theriogenology.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 07/07/2022] [Indexed: 11/21/2022]
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5
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Yu S, Wang Z, Zhang L, Nie Y, Deng Y, Liu R, Diao J, Zhou Z. Possible changes in trade-off strategy in female lizards (Eremias argus) during hibernation following exposure to chlorantraniliprole: Impact on the HPG axis and the energy mobilization. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 184:105059. [PMID: 35715026 DOI: 10.1016/j.pestbp.2022.105059] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 02/17/2022] [Accepted: 02/17/2022] [Indexed: 06/15/2023]
Abstract
Hibernation is a short-term survival strategy for ectotherms to cope with cold weather and food shortages. The energy sources stored before hibernation are used not only in the winter, but also in preparation for reproduction. Reproductive physiology and behavior are primarily regulated by the hypothalamus-pituitary-gonad (HPG) axis. In this study, we examined endocrine hormone changes in the HPG axis of female lizards (Eremias argus) after chlorantraniliprole insecticide (CAP) exposure during hibernation. The levels of gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone and progesterone were significantly decreased and the level of testosterone (T) was significantly increased after 135d experiment. This study verified the possible endocrine disrupting effects of CAP. More energy material consumption was observed in CAP treated group. Female E. argus preferred to invest energy to present survival when exposed to CAP, rather than to reserve material for following reproductive activity.
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Affiliation(s)
- Simin Yu
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Zikang Wang
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Luyao Zhang
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Yufan Nie
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Yue Deng
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Rui Liu
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Jinling Diao
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China
| | - Zhiqiang Zhou
- Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China.
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6
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Overwinter behavior, movement, and survival in a recently reintroduced, endangered amphibian, Rana muscosa. J Nat Conserv 2021. [DOI: 10.1016/j.jnc.2021.126086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Kouba AJ, Langhorne CJ, Willard ST, Smith T, Kouba CK. Spermiation response to exogenous hormone therapy in hibernated and non-hibernated boreal toads (Anaxyrus boreas boreas). Reprod Fertil Dev 2021; 34:453-460. [PMID: 34717792 DOI: 10.1071/rd21033] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 09/08/2021] [Indexed: 11/23/2022] Open
Abstract
Conservation programs for threatened high- elevation amphibian species rely on hibernation to trigger appropriate male reproductive behaviours and gametogenesis. Although common practice and anecdotal observations have supported the practice of hibernation, there is limited empirical evidence documenting the effects on reproduction in these species. In this study, the effect of hibernation on sperm quantity and quality was evaluated for the alpine species Anaxyrus boreas boreas. Hibernated (n=19) and non-hibernated (n=21) male toads were administered 10IUg-1 body weight (BW) human chorionic gonadotropin (hCG) and spermic urine was collected over 24h. Hibernation had no effect on the number of males undergoing spermatogenesis, but hibernated males produced sperm in higher concentrations. Sperm quality was measured in terms of total motility, forward progressive motility and quality of forward progression. Although there was no difference in the total sperm motility of samples from hibernated and non-hibernated toads, the percentage of sperm exhibiting forward progressive motility and the quality of forward progression was significantly greater from hibernated toads. These results support our hypothesis that hibernation impacts both sperm quantity and quality in male boreal toads. This study will better inform captive breeding management decisions for threatened alpine species, in imminent danger of extinction.
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Affiliation(s)
- Andrew J Kouba
- Wildlife, Fisheries, and Aquaculture Department, Mississippi State University, Mississippi State, MS 39762, USA
| | - Cecilia J Langhorne
- Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, Mississippi State University, Mississippi State, MS 39762, USA
| | - Scott T Willard
- Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, Mississippi State University, Mississippi State, MS 39762, USA
| | - Theodore Smith
- Native Aquatic Species Restoration Facility, Colorado Parks and Wildlife, Alamosa, CO 81101, USA
| | - Carrie K Kouba
- Biochemistry, Molecular Biology, Entomology and Plant Pathology Department, Mississippi State University, Mississippi State, MS 39762, USA
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8
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Silla AJ, Calatayud NE, Trudeau VL. Amphibian reproductive technologies: approaches and welfare considerations. CONSERVATION PHYSIOLOGY 2021; 9:coab011. [PMID: 33763231 PMCID: PMC7976225 DOI: 10.1093/conphys/coab011] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 01/29/2021] [Accepted: 02/07/2021] [Indexed: 06/12/2023]
Abstract
Captive breeding and reintroduction programs have been established for several threatened amphibian species globally, but with varied success. This reflects our relatively poor understanding of the hormonal control of amphibian reproduction and the stimuli required to initiate and complete reproductive events. While the amphibian hypothalamo-pituitary-gonadal (HPG) axis shares fundamental similarities with both teleosts and tetrapods, there are more species differences than previously assumed. As a result, many amphibian captive breeding programs fail to reliably initiate breeding behaviour, achieve high rates of fertilization or generate large numbers of healthy, genetically diverse offspring. Reproductive technologies have the potential to overcome these challenges but should be used in concert with traditional methods that manipulate environmental conditions (including temperature, nutrition and social environment). Species-dependent methods for handling, restraint and hormone administration (including route and frequency) are discussed to ensure optimal welfare of captive breeding stock. We summarize advances in hormone therapies and discuss two case studies that illustrate some of the challenges and successes with amphibian reproductive technologies: the mountain yellow-legged frog (Rana muscosa; USA) and the northern corroboree frog (Pseudophryne pengilleyi; Australia). Further research is required to develop hormone therapies for a greater number of species to boost global conservation efforts.
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Affiliation(s)
- Aimee J Silla
- Corresponding author: School of Earth, Atmospheric and Life Sciences, University of Wollongong, Northfields Ave, Wollongong, New South Wales 2522, Australia.
| | - Natalie E Calatayud
- Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Taronga, Western Plains Zoo, Obley Rd, Dubbo, New South Wales 2830, Australia
- San Diego Zoo Global-Beckman Center for Conservation Research, San Pasqual Valley Rd, Escondido, CA 92027, USA
| | - Vance L Trudeau
- Department of Biology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
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9
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Benefits of overwintering in the conservation breeding and translocation of a critically endangered amphibian. CONSERVATION SCIENCE AND PRACTICE 2021. [DOI: 10.1111/csp2.341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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10
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Lin JQ, Yu J, Jiang H, Zhang Y, Wan QH, Fang SG. Multi-omics analysis reveals that natural hibernation is crucial for oocyte maturation in the female Chinese alligator. BMC Genomics 2020; 21:774. [PMID: 33167853 PMCID: PMC7653761 DOI: 10.1186/s12864-020-07187-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 10/26/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Hibernation in an appropriate environment not only is important for the survival of hibernators in winter, but also is crucial for breeding in the following season for many hibernating species. However, the genetic and epigenetic mechanism underlying this process remain unclear. In the current study, we performed an integrative multi-omics analysis of gonads collected from Chinese alligators that overwintered in wild cave and artificial warmroom to explore transcriptomic and epigenomic alternations in these organs. RESULTS The data revealed that in the breeding season, female alligators were more strongly affected in terms of gene expression than males by non-hibernation because of overwintering in a warm room, especially for genes related to oocyte maturation, and this effect commenced in winter with the downregulation of STAR, which is the rate limiting factor of steroid biosynthesis. Further, miRNAs were found to play essential roles in this negative effect of overwintering in the warm room on hibernation. The upregulated miRNAs likely were responsible for the suppression of oocyte maturation in the breeding season. Finally, DNA methylome changes, especially hypomethylation, were found to play an important role in the alterations in ovarian function-related gene expression induced by non-hibernation. CONCLUSIONS Our study revealed the crucial role of hibernation quality for oocyte maturation in the Chinese alligator and the underlying genetic and epigenetic mechanisms, and highlights the importance of habitat, and especially, the overwintering site, in the conservation of not only the Chinese alligator, but also other endangered hibernators.
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Affiliation(s)
- Jian-Qing Lin
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Jun Yu
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Hua Jiang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yi Zhang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Qiu-Hong Wan
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Sheng-Guo Fang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China.
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11
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Hammond TT, Curtis MJ, Jacobs LE, Tobler MW, Swaisgood RR, Shier DM. Behavior and detection method influence detection probability of a translocated, endangered amphibian. Anim Conserv 2020. [DOI: 10.1111/acv.12645] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
| | | | - Leah E. Jacobs
- San Diego Zoo Institute for Conservation Research Escondido CA USA
| | | | | | - Debra M. Shier
- San Diego Zoo Institute for Conservation Research Escondido CA USA
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12
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Poo S, Hinkson KM, Stege E. Sperm output and body condition are maintained independently of hibernation in an endangered temperate amphibian. Reprod Fertil Dev 2019; 31:796-804. [PMID: 30514432 DOI: 10.1071/rd18073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 11/13/2018] [Indexed: 11/23/2022] Open
Abstract
Hibernation is an integral part of the life history of species living in seasonal environments. However, our knowledge about the link between hibernation and reproductive success in amphibians remains limited, which poses an obstacle for critical conservation efforts. To fill this gap, we quantified the effects of captive hibernation on sperm quality, sperm quantity and body condition in an endangered anuran, the Wyoming toad (Anaxyrus baxteri), and used naturally hibernated wild toads as a standard for comparison. We hypothesised that hibernation is essential for optimal sperm output but is detrimental to body condition. Sperm collection was performed using assisted reproductive technologies for both captive and wild toads. Contrary to our hypotheses, no differences were observed in sperm metrics (total number of cells, concentration, motility and viability) or in body condition across captive treatment groups (0, 30 or 60 days of hibernation). Moreover, no difference was found between sperm metrics of captive toads and wild toads. These unexpected findings suggest that hibernation may not be an essential process for spermiation in A. baxteri while using exogenous hormones, and illustrate the potential of temperate amphibians to adapt to varying environmental conditions during winter months.
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Affiliation(s)
- Sinlan Poo
- Department of Research and Conservation, Memphis Zoo, 2000 Prentiss Place, Memphis, TN 38112, USA
| | - Kristin M Hinkson
- Department of Research and Conservation, Memphis Zoo, 2000 Prentiss Place, Memphis, TN 38112, USA
| | - Edward Stege
- US Fish and Wildlife Services, Leadville National Fish Hatchery, 2846 Highway 300, Leadville, CO 80461, USA
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13
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Calatayud NE, Stoops M, Durrant BS. Ovarian control and monitoring in amphibians. Theriogenology 2017; 109:70-81. [PMID: 29325879 DOI: 10.1016/j.theriogenology.2017.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/01/2017] [Indexed: 12/29/2022]
Abstract
Amphibian evolution spans over 350 million years, consequently this taxonomic group displays a wide, complex array of physiological adaptations and their diverse modes of reproduction are a prime example. Reproduction can be affected by taxonomy, geographic and altitudinal distribution, and environmental factors. With some exceptions, amphibians can be categorized into discontinuous (strictly seasonal) and continuous breeders. Temperature and its close association with other proximate and genetic factors control reproduction via a tight relationship with circadian rhythms which drive genetic and hormonal responses to the environment. In recent times, the relationship of proximate factors and reproduction has directly or indirectly lead to the decline of this taxonomic group. Conservationists are tackling the rapid loss of species through a wide range of approaches including captive rescue. However, there is still much to be learned about the mechanisms of reproductive control and its requirements in order to fabricate species-appropriate captive environments that address a variety of reproductive strategies. As with other taxonomic groups, assisted reproductive technologies and other reproductive monitoring tools such as ultrasound, hormone analysis and body condition indices can assist conservationists in optimizing captive husbandry and breeding. In this review we discuss some of the mechanisms of ovarian control and the different tools being used to monitor female reproduction.
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Affiliation(s)
- N E Calatayud
- San Diego Zoo Global, Institute for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92027, United States.
| | - M Stoops
- Cincinnati Zoo & Botanical Garden, Center for Conservation and Research of Endangered Wildlife, 3400 Vine Street, Cincinnati, OH 45220, United States
| | - B S Durrant
- San Diego Zoo Global, Institute for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92027, United States
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14
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Currylow AFT, Mandimbihasina A, Gibbons P, Bekarany E, Stanford CB, Louis EE, Crocker DE. Comparative ecophysiology of a critically endangered (CR) ectotherm: Implications for conservation management. PLoS One 2017; 12:e0182004. [PMID: 28813439 PMCID: PMC5558934 DOI: 10.1371/journal.pone.0182004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 07/11/2017] [Indexed: 12/25/2022] Open
Abstract
Captive breeding is a vital conservation tool for many endangered species programs. It is often a last resort when wild animal population numbers drop to below critical minimums for natural reproduction. However, critical ecophysiological information of wild counterparts may not be well documented or understood, leading to years of minimal breeding successes. We collected endocrine and associated ecological data on a critically endangered ectotherm concurrently in the wild and in captivity over several years. We tracked plasma concentrations of steroid stress and reproductive hormones, body condition, activity, and environmental parameters in three populations (one wild and two geographically distinct captive) of ploughshare tortoise (Astrochelys yniphora). Hormone profiles along with environmental and behavioral data are presented and compared. We show that animals have particular seasonal environmental requirements that can affect annual reproduction, captivity affects reproductive state, and sociality may be required at certain times of the year for breeding to be successful. Our data suggest that changes in climatic conditions experienced by individuals, either due to decades-long shifts or hemispheric differences when translocated from their native range, can stifle breeding success for several years while the animals physiologically acclimatize. We also found that captivity affects stress (plasma corticosterone) and body condition of adults and juveniles differently and seasonally. Our results indicate that phenotypic plasticity in reproduction and behavior is related to environmental cues in long-lived ectotherms, and detailed ecophysiological data should be used when establishing and improving captive husbandry conditions for conservation breeding programs. Further, considering the recent revelation of this tortoises’ possible extirpation from the wild, these data are critically opportune and may be key to the survival of this species.
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Affiliation(s)
- Andrea F. T. Currylow
- Integrative and Evolutionary Biology, University of Southern California, Los Angeles, California, United States of America
- * E-mail:
| | | | - Paul Gibbons
- Turtle Conservancy, Ojai, California, United States of America
| | - Ernest Bekarany
- Durrell Wildlife Conservation Trust, Antananarivo, Madagascar
| | - Craig B. Stanford
- Integrative and Evolutionary Biology, University of Southern California, Los Angeles, California, United States of America
- Turtle Conservancy, Ojai, California, United States of America
- Herpetology Section, Los Angeles County Natural History Museum, Los Angeles, California, United States of America
| | - Edward E. Louis
- Madagascar Biodiversity Partnership, Conservation Genetics Department, Omaha’s Henry Doorly Zoo and Aquarium, Omaha, Nebraska, United States of America
| | - Daniel E. Crocker
- Department of Biology, Sonoma State University, Rohnert Park, California, United States of America
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15
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McCartney-Melstad E, Shaffer HB. Amphibian molecular ecology and how it has informed conservation. Mol Ecol 2015; 24:5084-109. [PMID: 26437125 DOI: 10.1111/mec.13391] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 09/15/2015] [Accepted: 09/16/2015] [Indexed: 02/02/2023]
Abstract
Molecular ecology has become one of the key tools in the modern conservationist's kit. Here we review three areas where molecular ecology has been applied to amphibian conservation: genes on landscapes, within-population processes, and genes that matter. We summarize relevant analytical methods, recent important studies from the amphibian literature, and conservation implications for each section. Finally, we include five in-depth examples of how molecular ecology has been successfully applied to specific amphibian systems.
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Affiliation(s)
- Evan McCartney-Melstad
- Department of Ecology and Evolutionary Biology, La Kretz Center for California Conservation Science, and Institute of the Environment and Sustainability, University of California, Los Angeles, 610 Charles E Young Drive South, Los Angeles, CA, USA
| | - H Bradley Shaffer
- Department of Ecology and Evolutionary Biology, La Kretz Center for California Conservation Science, and Institute of the Environment and Sustainability, University of California, Los Angeles, 610 Charles E Young Drive South, Los Angeles, CA, USA
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