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Arregui L, Bosch J. Gamete Collection, Artificial Fertilization and Captive-Rearing of Eggs in a Terrestrial-Breeding Anuran with Parental Care: Alytes obstetricans. Animals (Basel) 2023; 13:2802. [PMID: 37685066 PMCID: PMC10487003 DOI: 10.3390/ani13172802] [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: 07/31/2023] [Revised: 08/28/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
The genus Alytes consists of six primitive terrestrial-breeding species (five of them endangered or present in restricted distributions) with unique male parental care. Alytes obstetricans was used as a model for the development of assisted reproductive technologies for gamete collection, artificial fertilization and captive-rearing of embryos. Sperm collection was achieved with human chorionic gonadotropin (hCG), but only 17 to 50% of males responded to the hormone. In addition, an effect of captivity on sperm quality was observed. A combination of gonadotropin-releasing hormone agonist (GnRHa) and hCG was tested for induction of ovulation, and 100% of females responded to the treatment. Recently collected sperm was used in artificial fertilization, and 10% of eggs showed complete embryo development. To design a method for captive-rearing of embryos, natural clutches (n = 13) were removed from males and divided into two sub-clutches. One was kept with all eggs together and in the other, the egg string was cut and eggs were split individually. All sub-clutches with eggs kept separated presented embryo survival (ranging from 27 to 61%) that hatched normally, while only one sub-clutch with embryos maintained together had some embryo survival (36%). These results may contribute to the management of this and related species.
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Affiliation(s)
- Lucía Arregui
- Centro de Investigación, Seguimiento y Evaluación, Parque Nacional de la Sierra de Guadarrama, Ctra. M-604, Km 27.6, Rascafria, 28740 Madrid, Spain;
| | - Jaime Bosch
- Centro de Investigación, Seguimiento y Evaluación, Parque Nacional de la Sierra de Guadarrama, Ctra. M-604, Km 27.6, Rascafria, 28740 Madrid, Spain;
- IMIB-Biodiversity Research Institute, University of Oviedo-CSIC-Principality of Asturias, C/Gonzalo Gutiérrez Quirón S/N, Mieres, 33600 Asturias, Spain
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Lampert SS, Burger IJ, Julien AR, Gillis AB, Kouba AJ, Barber D, Kouba CK. Sperm Cryopreservation as a Tool for Amphibian Conservation: Production of F2 Generation Offspring from Cryo-Produced F1 Progeny. Animals (Basel) 2022; 13:ani13010053. [PMID: 36611663 PMCID: PMC9817882 DOI: 10.3390/ani13010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/30/2022] [Accepted: 12/20/2022] [Indexed: 12/25/2022] Open
Abstract
Sperm cryopreservation and biobanking are emerging as tools for supporting genetic management of small and threatened populations in amphibian conservation programs. However, there is little to no evidence demonstrating reproductive maturity and viability of offspring generated with cryopreserved sperm, potentially limiting widespread integration of these technologies. The purpose of this report is to demonstrate that amphibian sperm can be cryopreserved and thawed to successfully produce individuals of an F1 generation that can reach adulthood and reproductive maturity, to generating viable gametes and an F2 generation. Species-specific exogenous hormones were administered to both F0 and F1 adults to stimulate spermiation and oviposition in the eastern tiger salamander (Ambystoma tigrinum), dusky gopher frog (Lithobates sevosa), and Puerto Rican crested toad (Peltophryne lemur). Sperm cells collected non-lethally from F0 adults were cryopreserved, thawed, and used for in vitro fertilization (IVF) to produce F1 offspring. Individuals of the F1 generation are shown to reach adulthood, express viable gametes, and produce offspring through facilitated breeding, or IVF. The production of amphibian F2 generations shown here demonstrates that amphibian sperm collected non-lethally can be banked and used to generate reproductively viable animals of subsequent generations, thus maintaining valuable genetic linages and diversity in threatened amphibian species. The incredible value that cryopreservation of sperm has for long-term genetic management aids in the sustainability of both in situ and ex situ conservation efforts for this taxon.
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Affiliation(s)
- Shaina S. Lampert
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Isabella J. Burger
- Department of Wildlife, Fisheries, and Aquaculture, Mississippi State University, Mississippi State, MS 39762, USA
| | - Allison R. Julien
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Amanda B. Gillis
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Andrew J. Kouba
- Department of Wildlife, Fisheries, and Aquaculture, Mississippi State University, Mississippi State, MS 39762, USA
| | - Diane Barber
- Department of Ectotherms, Fort Worth Zoo, Fort Worth, TX 76110, USA
| | - Carrie K. Kouba
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA
- Correspondence: ; Tel.: +16-623-252-640
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Burger IJ, Lampert SS, Kouba CK, Morin DJ, Kouba AJ. Development of an amphibian sperm biobanking protocol for genetic management and population sustainability. CONSERVATION PHYSIOLOGY 2022; 10:coac032. [PMID: 35620647 PMCID: PMC9127716 DOI: 10.1093/conphys/coac032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/01/2022] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
Sperm cryopreservation is a vital tool in amphibian assisted reproductive technologies that aids in genetic and population management, specifically for at-risk species. Significant advancements have been made in the cryopreservation of amphibian sperm, yet there is little information on how the cryopreservation process influences fertilization and embryonic development. In this study, we tested several cryoprotective agents (CPAs) and freezing rates on sperm recovery, fertilization potential and embryo development using Fowler's toads (Anaxyrus fowleri) as a model amphibian species for application to at-risk anurans. Three cryoprotectant treatments were tested, which included 10% trehalose + 0.25% bovine serum albumin with (1) 5% N,N-dimethylformamide (DMFA); (2) 10% DMFA; or (3) 10% dimethyl sulfoxide (DMSO). Additionally, sperm in each cryoprotectant was frozen at two different rates, -32 to -45°C/min and -20 to -29°C/min. Post-thaw sperm analysis included motility, morphology, viability, fertilization success and embryo development. Results show that 10% DMFA produced significantly higher (P = 0.005) post-thaw sperm motility than 5% DMFA and was similar to 10% DMSO. Furthermore, sperm frozen at -32 to -45°C/min had significantly higher post-thaw motility (P < 0.001) compared to sperm frozen at -20 to -29°C/min. We also found that embryos fertilized with sperm frozen with 5% DMFA resulted in significantly higher (P = 0.02) cleavage than 10% DMSO, yet there was no other effect of CPA on fertilization or embryo development. Furthermore, embryos fertilized with sperm frozen at -32 to -45°C/min resulted in significantly higher cleavage (P = 0.001), neurulation (P = 0.001) and hatching (P = 0.002) numbers than sperm frozen at a rate of -20 to -29°C/min. Overall, eggs fertilized with frozen-thawed sperm produced 1327 tadpoles. These results provide insight towards a biobanking strategy that can be applied to imperilled species to preserve genetic lineages and bolster offspring genetic diversity for reintroduction.
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Affiliation(s)
- Isabella J Burger
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, 39762, USA
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State, MS, 39762, USA
| | - Shaina S Lampert
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State, MS, 39762, USA
| | - Carrie K Kouba
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State, MS, 39762, USA
| | - Dana J Morin
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, 39762, USA
| | - Andrew J Kouba
- Corresponding author: Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, 39762, USA.
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Glass Campbell L, Anderson KA, Marcec‐Greaves R. Topical application of hormone gonadotropin‐releasing hormone (
GnRH‐A
) stimulates reproduction in the endangered Texas blind salamander (
Eurycea rathbuni
). CONSERVATION SCIENCE AND PRACTICE 2021. [DOI: 10.1111/csp2.609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
| | - Kelsey A. Anderson
- US Fish and Wildlife Service San Marcos Aquatic Resources Center San Marcos Texas USA
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Burger I, Julien AR, Kouba AJ, Barber D, Counsell KR, Pacheco C, Krebs J, Kouba CK. Linking in‐situ and ex‐situ populations of threatened amphibians through genome banking. CONSERVATION SCIENCE AND PRACTICE 2021. [DOI: 10.1111/csp2.525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Isabella Burger
- Department of Wildlife, Fisheries and Aquaculture Mississippi State University Mississippi State Mississippi USA
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology Mississippi State University Mississippi State Mississippi USA
| | - Allison R. Julien
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology Mississippi State University Mississippi State Mississippi USA
| | - Andrew J. Kouba
- Department of Wildlife, Fisheries and Aquaculture Mississippi State University Mississippi State Mississippi USA
| | - Diane Barber
- Department of Ectotherms Fort Worth Zoo Fort Worth Texas USA
| | - Kristen R. Counsell
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology Mississippi State University Mississippi State Mississippi USA
| | - Carlos Pacheco
- Caribbean Ecological Services Field Office, U.S. Fish and Wildlife Service Boqueron Puerto Rico USA
| | - Jessi Krebs
- Omaha's Henry Doorly Zoo and Aquarium Omaha Nebraska USA
| | - Carrie K. Kouba
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology Mississippi State University Mississippi State Mississippi USA
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Efficacy of hormone stimulation on sperm production in an alpine amphibian (Anaxyrus boreas boreas) and the impact of short-term storage on sperm quality. ZOOLOGY 2021; 146:125912. [PMID: 33743452 DOI: 10.1016/j.zool.2021.125912] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 02/24/2021] [Accepted: 02/28/2021] [Indexed: 11/22/2022]
Abstract
The Southern Rocky Mountain boreal toad (Anaxyrus boreas boreas) has disappeared from much of its range in the alpine regions of Central and Western North America, and restoration efforts are compromised by limited knowledge of this species' reproductive biology. This study aimed to establish whether assisted reproductive techniques could be used to improve breeding output in captive boreal toads by determining the most effective concentration of human chorionic gonadotropin (hCG) for induction of spermiation and viability of sperm during cold storage. Male toads (n = 21) were treated with a Low (3 IU g-1), Medium (10 IU g-1), or High (15 IU g-1) concentration of hCG and spermic urine samples were collected over 24 hrs. Treatment effectiveness was evaluated by measuring the response rate, Total Motility (TM), Forward Progressive Motility (FPM), Quality of FPM (QFPM), and concentration. For short-term cold storage, spermic urine samples (n = 13) were stored at 4 °C for 14 days and sperm TM and FPM monitored daily. All treatments induced spermiation; however, a greater number of toads produced sperm in the Medium and High treatments compared to the Low. Overall, TM, FPM, QFPM and sperm concentration were similar across all three treatments, but variation existed in the timing and duration of peak sperm production. Sperm motility was maintained for up to 14 days in cold storage, although the quality slowly decreased over time. An effective reproduction strategy for the boreal toad will provide a means to improve captive breeding efforts and increase our understanding of the reproductive physiology of alpine Bufonids.
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Della Togna G, Howell LG, Clulow J, Langhorne CJ, Marcec-Greaves R, Calatayud NE. Evaluating amphibian biobanking and reproduction for captive breeding programs according to the Amphibian Conservation Action Plan objectives. Theriogenology 2020; 150:412-431. [PMID: 32127175 DOI: 10.1016/j.theriogenology.2020.02.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 02/16/2020] [Indexed: 01/18/2023]
Abstract
The Amphibian Conservation Action Plan (ACAP), published in 2007, is a formal document of international significance that proposed eleven relevant actions for global amphibian conservation. Action seven of the ACAP document addresses the use of amphibian captive programs as a conservation tool. Appendix material under this action explores the potential use of Genome Resource Banking (biobanking) as an urgently needed tool for these captive programs. ACAP proposed twelve objectives for Genome Resource Banking which exhibit little emphasis on reproduction as a vital underlying science for amphibian Captive Breeding Programs (CBP's). Here we have reassessed the original twelve ACAP objectives for amphibian reproduction and biobanking for CBP's as a contribution to future ACAP review processes. We have reviewed recent advances since the original objectives, as well as highlighted weaknesses and strengths for each of these objectives. We make various scientific, policy and economic recommendations based on the current reality and recent advances in relevant science in order to inform future ACAP towards new global objectives. The number of amphibian CBP'S has escalated in recent years and reproductive success is not always easily accomplished. Increases in applied and fundamental research on the natural history and reproductive biology of these species, followed by the appropriate development and application of artificial reproductive technologies (ART's) and the incorporation of genome resource banks (GRB's), may turn CBP's into a more powerful tool for amphibian conservation.
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Affiliation(s)
- Gina Della Togna
- Universidad Interamericana de Panama, Dirección de Investigación, Campus Central, Avenida Ricardo J. Alfaro, Panama; Smithsonian Tropical Research Institute, Panama Amphibian Rescue and Conservation Project, Panama.
| | - Lachlan G Howell
- University of Newcastle, Conservation Biology Research Group, University Drive, Callaghan, NSW, 2308, Australia
| | - John Clulow
- University of Newcastle, Conservation Biology Research Group, University Drive, Callaghan, NSW, 2308, Australia
| | | | - Ruth Marcec-Greaves
- National Amphibian Conservation Center, Detroit Zoological Society, Royal Oak, MI, 48067, USA
| | - Natalie E Calatayud
- San Diego Zoo Institute for Conservation Research, San Pasqual Valley Road, Escondido, CA, 92027, USA; Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Taronga Western Plains Zoo, Dubbo, NSW, 2830, Australia
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Silla AJ, Roberts JD, Byrne PG. The effect of injection and topical application of hCG and GnRH agonist to induce sperm-release in the roseate frog, Geocrinia rosea. CONSERVATION PHYSIOLOGY 2020; 8:coaa104. [PMID: 33304589 PMCID: PMC7720084 DOI: 10.1093/conphys/coaa104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/08/2020] [Accepted: 10/27/2020] [Indexed: 05/08/2023]
Abstract
Reproductive technologies may assist amphibian conservation breeding programs (CBPs) to achieve propagation targets and genetic management goals. However, a trial-and-error approach to protocol refinement has led to few amphibian CBPs routinely employing reproductive technologies with predictable outcomes. Additionally, while injections can be safely administered to amphibians, perceived animal welfare risks, such as injury and disease transmission, warrant the development of alternative hormone administration protocols. The present study investigated the spermiation response of roseate frogs, Geocrinia rosea, administered various doses of human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone agonist (GnRH-a) via subcutaneous injection. This study also quantified the spermiation response of frogs administered both hormones via topical application. Total sperm, sperm concentration and sperm viability were assessed over a 12-h period post hormone administration. Males released sperm in response to the injection of hCG (88-100% response; 5, 10 or 20 IU), but all samples collected from males administered hCG topically (100, 100 + DMSO or 200 IU hCG) were aspermic. In contrast, males consistently released sperm in response to both the injection (100% response; 1, 5 or 10 μg), or topical application (80-100% response; 50, 50 + DMSO or 100 μg) of GnRH-a. Overall, the administration of GnRH-a was more effective at inducing spermiation than hCG. Mean total sperm and sperm concentration were highest in response to the optimal topically applied dose of 100 μg GnRH-a (mean total sperm = 2.44 × 103, sperm concentration = 1.48 × 105 sperm/ml). We provide novel evidence that topical application provides a viable alternative to injection for the administration of GnRH-a to induce spermiation in amphibians.
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Affiliation(s)
- Aimee J Silla
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, Northfields Ave, NSW 2522, Australia
- School of Biological Sciences and Centre for Evolutionary Biology, University of Western Australia, Stirling Highway, Nedlands, WA 6009, Australia
- Corresponding author: School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, Northfields Ave, NSW 2522, Australia.
| | - J Dale Roberts
- School of Biological Sciences and Centre for Evolutionary Biology, University of Western Australia, Stirling Highway, Nedlands, WA 6009, Australia
| | - Phillip G Byrne
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, Northfields Ave, NSW 2522, Australia
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