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Andrology2026; doi: 10.1111/andr.70249

Hyperactivation and Tyrosine Phosphorylation of Cryopreserved Stallion Spermatozoa in Relation to Conventional In Vitro Fertilization Blastocyst Production.

Abstract: Challenges in establishing clinical conventional in vitro fertilization (IVF) in horses include variation in sperm and oocyte quality, which can be affected by mare age. Extended preincubation of stallion spermatozoa has resulted in successful IVF. However, there is limited research on the impact of preincubation on sperm characteristics and IVF success. Objective: Responses of frozen-thawed stallion spermatozoa over time under IVF preincubation conditions were evaluated, and samples based on specific responses were tested for their ability to fertilize oocytes, including those from older mares, using conventional IVF. Methods: Frozen-thawed spermatozoa were sorted, incubated for 10 h in capacitating conditions, and evaluated for motility, membrane integrity, mitochondrial function, and protein tyrosine phosphorylation (PY). Sperm samples for IVF were selected based on motion and PY patterns using oocytes from younger and older mares. Accessory spermatozoa binding to the zona pellucida (ZP), fertilization, cleavage, and blastocyst rates were assessed. Results: Sperm motility, velocities, linearity, and straightness were significantly reduced during incubation, while the amplitude of lateral head displacement increased. Plasma membrane integrity and mitochondrial activity were also significantly reduced over time. After 5 h of incubation, an increase in tyrosine-phosphorylated proteins was observed, occurring primarily in the equatorial segment, but also including the midpiece or tail. The response of sperm samples to capacitating conditions varied. Sperm samples selected for IVF were successful at fertilizing oocytes from younger and older mares, with more accessory spermatozoa bound to ZP in oocytes from younger than older mares, although cleavage and blastocyst rates did not differ. Conclusions: We concluded that changes in sperm motion and PY patterns were indicative of hyperactivation and capacitation, although wide variation occurred among stallions. Cryopreserved spermatozoa can successfully fertilize oocytes using conventional IVF. Age of the mare oocyte donor does not appear to affect fertilization after IVF.
© 2026 The Author(s). Andrology published by John Wiley & Sons Ltd on behalf of American Society of Andrology and European Academy of Andrology.
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Publication Date: 2026-04-27 PubMed ID: 42046323DOI: 10.1111/andr.70249Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study investigated how incubation conditions affect the function of frozen-thawed stallion sperm and their ability to fertilize horse oocytes using conventional in vitro fertilization (IVF).
  • It specifically examined sperm hyperactivation, tyrosine phosphorylation, and the influence of mare age on fertilization and embryo development.

Introduction and Research Motivation

  • Establishing conventional IVF protocols in horses is challenging due to variations in sperm and oocyte quality.
  • Mare age impacts oocyte quality and may influence IVF success.
  • Previous work showed that extended preincubation of stallion sperm improved IVF outcomes, but the effects of preincubation on sperm characteristics and IVF success remain underexplored.

Objectives

  • To evaluate the changes in frozen-thawed stallion sperm over time during IVF preincubation.
  • To assess the relationship between these sperm characteristics and their fertilizing ability, including in oocytes from older mares.
  • To analyze sperm motility, membrane integrity, mitochondrial function, and protein tyrosine phosphorylation (PY) during incubation.
  • To determine how these sperm traits relate to IVF outcomes, such as fertilization, cleavage, and blastocyst production.

Methods

  • Sperm Preparation:
    • Frozen-thawed stallion sperm samples were sorted and incubated for 10 hours in conditions that promote capacitation (a process that enables sperm to fertilize an egg).
  • Sperm Evaluation:
    • Motility parameters including velocity, linearity, and straightness were measured.
    • Membrane integrity and mitochondrial activity (indicators of sperm health and energy production) were assessed.
    • Protein tyrosine phosphorylation (PY) was detected to evaluate capacitation status, focusing on localization in sperm segments such as the equatorial segment, midpiece, and tail.
  • Selection for IVF:
    • Sperm samples were selected based on motility and PY patterns for IVF experiments.
    • Oocytes were retrieved from mares of different ages — both younger and older.
  • Assessment of Fertilization Outcomes:
    • Measured accessory sperm binding to the zona pellucida (ZP), an outer membrane of the oocyte important for fertilization.
    • Determined fertilization rates, cleavage rates (early embryo cell division), and blastocyst formation rates (development into a late-stage embryo).

Key Findings

  • Sperm Motility Changes Over Incubation:
    • Overall motility, speed (velocity), linearity (straight path movement), and straightness decreased significantly during incubation.
    • Amplitude of lateral head displacement (a characteristic of hyperactivation) increased, indicating sperm became more hyperactivated over time.
  • Membrane and Mitochondrial Function:
    • Integrity of the sperm plasma membrane and mitochondrial activity declined with prolonged incubation.
  • Protein Tyrosine Phosphorylation (PY):
    • There was a noticeable increase in PY after 5 hours of incubation, especially in the equatorial segment of sperm, an area important for fusion with the egg.
    • Some phosphorylation was also observed in the midpiece and tail regions.
    • Variability between stallion samples was noted, reflecting differences in capacitation response.
  • Fertilization Outcomes:
    • Sperm samples selected for IVF based on motility and PY patterns successfully fertilized oocytes from both younger and older mares.
    • More sperm bound to the zona pellucida of oocytes from younger mares compared to older mares.
    • Despite differences in sperm binding, cleavage (early embryo development) and blastocyst (advanced embryo stage) formation rates did not differ significantly between oocytes from younger and older mares.

Conclusions and Implications

  • Changes in sperm motion patterns and tyrosine phosphorylation are indicators of capacitation and hyperactivation in cryopreserved stallion sperm.
  • There is notable variability in the response of sperm from different stallions to capacitating conditions.
  • Cryopreserved (frozen-thawed) stallion sperm can successfully fertilize oocytes using conventional IVF protocols, showing promise for equine reproductive technologies.
  • The age of the mare donating the oocyte does not appear to negatively affect fertilization success or early embryo development when conventional IVF is used.
  • This research highlights the importance of sperm selection based on functional parameters to improve IVF outcomes in horses.

Cite This Article

APA
Gonzalez-Castro RA, Porflidt CC, Ash AL, Rodriguez JS, Fleury PD, Squires EL, Carnevale EM. (2026). Hyperactivation and Tyrosine Phosphorylation of Cryopreserved Stallion Spermatozoa in Relation to Conventional In Vitro Fertilization Blastocyst Production. Andrology. https://doi.org/10.1111/andr.70249

Publication

Andrology
ISSN: 2047-2927
NlmUniqueID: 101585129
Country: England
Language: English

Researcher Affiliations

Gonzalez-Castro, Raul A
  • Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.
Porflidt, Carolina C
  • Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.
Ash, Alexandra L
  • Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.
Rodriguez, Jacobo S
  • Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.
Fleury, Perla D
  • In Vitro Equinos, Mogi Mirim, São Paulo, Brazil.
Squires, Edward L
  • In Vitro Equinos, Mogi Mirim, São Paulo, Brazil.
Carnevale, Elaine M
  • Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA.

References

This article includes 61 references
  1. Shingshetty L, Cameron NJ, Mclernon DJ, Bhattacharya S. Predictors of Success After In Vitro Fertilization. Fertility and Sterility Elsevier Inc 121, no. 5 (2024): 742–751.
    doi: 10.1016/j.fertnstert.2024.03.003google scholar: lookup
  2. Ferré LB, Kjelland ME, Strøbech LB, Hyttel P, Mermillod P, Ross PJ. Review: Recent Advances in Bovine In Vitro Embryo Production: Reproductive Biotechnology History and Methods. Animal 14, no. 5 (2020): 991–1004.
    doi: 10.1017/s1751731119002775google scholar: lookup
  3. IETS. Statistics of Embryo Production and Transfer in Domestic Farm Animals 2023. accessed March 10, 2025.
  4. Palmer E, Bezard J, Magistrini M, Duchamp G. In Vitro Fertilization in the Horse. A Retrospective Study. Journal of Reproduction and Fertility Supplement 44 (1991): 375–384.
  5. Bézard J. In Vitro Fertilization in the Mare. in International Scientific Conference on Biotechnics in Horse Reproduction (1992).
  6. Leemans B, Gadella BM, Stout TAE. Why Doesn't Conventional IVF Work in the Horse? The Equine Oviduct as a Microenvironment for Capacitation/Fertilization. Reproduction 152, no. 6 (2016): R233–R245.
    doi: 10.1530/rep-16-0420google scholar: lookup
  7. Martin-Pelaez S, de la Fuente A, Takahashi K. IVF With Frozen-Thawed Sperm After Prolonged Capacitation Yields Comparable Results to ICSI in Horses: A Morphokinetics Study. Theriogenology 232 (2025): 39–45.
    doi: 10.1016/j.theriogenology.2024.10.032google scholar: lookup
  8. Felix MR, Hinrichs K. Selection of Frozen-Thawed Semen for Standard In Vitro Fertilization. Journal of Equine Veterinary Science 125 (2023): 104648.
    doi: 10.1016/j.jevs.2023.104648google scholar: lookup
  9. Felix MR, Turner RM, Dobbie T, Hinrichs K. Successful In Vitro Fertilization in the Horse: Production of Blastocysts and Birth of Foals After Prolonged Sperm Incubation for Capacitation. Biology of Reproduction 107, no. 6 (2022): 1551–1564.
    doi: 10.1093/biolre/ioac172google scholar: lookup
  10. Leemans B, Stout TAE, De Schauwer C. Update on Mammalian Sperm Capacitation: How Much Does the Horse Differ From Other Species?. Reproduction (Cambridge, England) 157, no. 5 (2019): R181–R197.
    doi: 10.1530/repgoogle scholar: lookup
  11. Suarez SS. Interactions of Gametes With the Female Reproductive Tract. Cell and Tissue Research 363, no. 1 (2016): 185–194.
    doi: 10.1007/s00441-015-2244-2google scholar: lookup
  12. Aitken RJ, Nixon B. Sperm Capacitation: A Distant Landscape Glimpsed but Unexplored. Molecular Human Reproduction 19, no. 12 (2013): 785–793.
    doi: 10.1093/molehr/gat067google scholar: lookup
  13. Yanagimachi R. Mammalian fertilization. in The Physiology of Reproduction, 2nd ed., ed. Knobil E. and Neil J. D. (Raven Press, 1994), 189–317.
  14. Leemans B, Gadella BM, Stout TAE, Nelis H, Hoogewijs M, Van Soom A. An Alkaline Follicular Fluid Fraction Induces Capacitation and Limited Release of Oviduct Epithelium-Bound Stallion Sperm. Reproduction (Cambridge, England) 150, no. 3 (2015): 193–208.
    doi: 10.1530/rep-15-0178google scholar: lookup
  15. Leemans B, Gadella BM, Sostaric E. Oviduct Binding and Elevated Environmental pH Induce Protein Tyrosine Phosphorylation in Stallion Spermatozoa. Biology of Reproduction 91, no. 1 (2014).
    doi: 10.1095/biolreprod.113.116418google scholar: lookup
  16. Carnevale EM, Griffin PG, Ginther OJ. Age‐Associated Subfertility Before Entry of Embryos Into the Uterus in Mares. Equine Veterinary Journal 25, no. S15 (1993): 31–35.
    doi: 10.1111/j.2042-3306.1993.tb04820.xgoogle scholar: lookup
  17. Brinsko SP, Ball BA, Miller PG, Thomas PGA, Ellington JE. In Vitro Development of Day 2 Embryos Obtained From Young, Fertile Mares and Aged, Subfertile Mares. Journal of Reproduction and Fertility no. 102 (1994): 371–378.
    doi: 10.1530/jrf.0.1020371google scholar: lookup
  18. Ishikawa-Yamauchi Y, Emori C, Kobayashi K. Age‐Related Alterations in the Surface Morphology of Zona Pellucida Prevent Sperm Binding to Oocyte and Affect Fertilization. Journal of Reproductive Immunology 153 (2022): 103727.
    doi: 10.1016/j.jri.2022.103727google scholar: lookup
  19. Ishikawa-Yamauchi Y, Emori C, Mori H. Age‐Associated Aberrations of the Cumulus‐Oocyte Interaction and in the Zona Pellucida Structure Reduce Fertility in Female Mice. Communications Biology 7, no. 1 (2024).
    doi: 10.1038/s42003-024-07305-zgoogle scholar: lookup
  20. Bresnahan DR, Lupole RE, Stilz CR, Carnevale EM. Effect of Mare Age on Transcript Abundance of Connexins‐37 and ‐43, Zona Pellucida Proteins, and Sperm Binding. Journal of Equine Veterinary Science 108 (2022).
    doi: 10.1016/j.jevs.2021.103796google scholar: lookup
  21. Kölle S, Dubois CS, Caillaud M, Lahuec C, Sinowatz F, Goudet G. Equine Zona Protein Synthesis and Zp Structure During Folliculogenesis, Oocyte Maturation, and Embryogenesis. Molecular Reproduction and Development 74, no. 7 (2007): 851–859.
    doi: 10.1002/mrd.20501google scholar: lookup
  22. Kirk ES, Squires EL, Graham JK. Comparison of In Vitro Laboratory Analyses With the Fertility of Cryopreserved Stallion Spermatozoa. Theriogenology 64, no. 6 (2005): 1422–1439.
    doi: 10.1016/j.theriogenology.2005.03.006google scholar: lookup
  23. Gonzalez-Castro RA, Trentin JM, Carnevale EM, Graham JK. Effects of Extender, Cryoprotectants and Thawing Protocol on Motility of Frozen‐Thawed Stallion Sperm That Were Refrozen for Intracytoplasmic Sperm Injection Doses. Theriogenology 136 (2019): 36–42.
    doi: 10.1016/j.theriogenology.2019.06.030google scholar: lookup
  24. Gonzalez-Castro RA, Carnevale EM. Use of Microfluidics to Sort Stallion Sperm for Intracytoplasmic Sperm Injection. Animal Reproduction Science 202, no. August 2018 (2019): 1–9.
    doi: 10.1016/j.anireprosci.2018.12.012google scholar: lookup
  25. Carnevale EM. Advances in Collection, Transport and Maturation of Equine Oocytes for Assisted Reproductive Techniques. Veterinary Clinics of North America—Equine Practice 32, no. 3 (2016): 379–399.
    doi: 10.1016/j.cveq.2016.07.002google scholar: lookup
  26. Martino NA, Dell'Aquila ME, Uranio MF. Effect of Holding Equine Oocytes in Meiosis Inhibitor‐Free Medium Before In Vitro Maturation and of Holding Temperature on Meiotic Suppression and Mitochondrial Energy/Redox Potential. Reproductive Biology and Endocrinology 12, no. 1 (2014): article number 99.
    doi: 10.1186/1477-7827-12-99google scholar: lookup
  27. Campos-Chillon F, Farmerie TA, Bouma GJ, Clay CM, Carnevale EM. Effects of Aging on Gene Expression and Mitochondrial DNA in the Equine Oocyte and Follicle Cells. Reproduction, Fertility, and Development 27, no. 6 (2015): 925–933.
    doi: 10.1071/rd14472google scholar: lookup
  28. Carnevale EM, Metcalf ES. Morphology, Developmental Stages and Quality Parameters of In Vitro‐Produced Equine Embryos. Reproduction, Fertility, and Development 31, no. 12 (2019): 1758–1770.
    doi: 10.1071/rd19257google scholar: lookup
  29. Mortimer ST, Mortimer D. Kinematics of Human Spermatozoa Incubated Under Capacitating Conditions. Journal of Andrology 11, no. 3 (1990): 195–203.
    doi: 10.1002/j.1939-4640.1990.tb03228.xgoogle scholar: lookup
  30. Mortimer ST. Andrology Lab Corner CASA‐Practical Aspects. Journal of Andrology 21, no. 4 (2000): 515–524.
    doi: 10.1111/j.1939-4640.2000.tb02116.xgoogle scholar: lookup
  31. Loux SC, Crawford KR, Ing NH. CatSper and the Relationship of Hyperactivated Motility to Intracellular Calcium and pH Kinetics in Equine Sperm. Biology of Reproduction 89, no. 5 (2013): 111708.
    doi: 10.1095/biolreprod.113.111708google scholar: lookup
  32. McPartlin LA, Suarez SS, Czaya CA, Hinrichs K, Bedford‐Guaus SJ. Hyperactivation of Stallion Sperm Is Required for Successful In Vitro Fertilization of Equine Oocytes. Biology of Reproduction 81, no. 1 (2009): 199–206.
    doi: 10.1095/biolreprod.108.074880google scholar: lookup
  33. McPartlin LA, Littell J, Mark E, Nelson JL, Travis AJ, Bedford‐Guaus SJ. A Defined Medium Supports Changes Consistent With Capacitation in Stallion Sperm, as Evidenced by Increases in Protein Tyrosine Phosphorylation and High Rates of Acrosomal Exocytosis. Theriogenology 69, no. 5 (2008): 639–650.
    doi: 10.1016/j.theriogenology.2007.11.016google scholar: lookup
  34. Yeste M. Sperm Cryopreservation Update: Cryodamage, Markers, and Factors Affecting the Sperm Freezability in Pigs. Theriogenology 85, no. 1 (2016): 47–64.
    doi: 10.1016/j.theriogenology.2015.09.047google scholar: lookup
  35. Yánez‐Ortiz I, Catalán J, Rodríguez‐Gil JE, Miró J, Yeste M. Advances in Sperm Cryopreservation in Farm Animals: Cattle, Horse, Pig and Sheep. Animal Reproduction Science 246 (2022): 106904.
    doi: 10.1016/j.anireprosci.2021.106904google scholar: lookup
  36. Thomas AD, Meyers SA, Ball BA. Capacitation‐Like Changes in Equine Spermatozoa Following Cryopreservation. Theriogenology 65, no. 8 (2006): 1531–1550.
    doi: 10.1016/j.theriogenology.2005.08.022google scholar: lookup
  37. Kerns K, Zigo M, Drobnis EZ, Sutovsky M, Sutovsky P. Zinc Ion Flux During Mammalian Sperm Capacitation. Nature Communications 9, no. 1 (2018): 2061.
    doi: 10.1038/s41467‐018‐04523‐ygoogle scholar: lookup
  38. Garner D, Johnson L. Viability Assessment of Mammalian Sperm Using SYBR‐14 and Propidium Iodide. Biology of Reproduction 53, no. 2 (1995): 276–284.
    doi: 10.1095/biolreprod53.2.276google scholar: lookup
  39. Peña FJ, Ball BA, Squires EL. A New Method for Evaluating Stallion Sperm Viability and Mitochondrial Membrane Potential in Fixed Semen Samples. Cytometry Part B, Clinical Cytometry 94, no. 2 (2017): 302–311.
    doi: 10.1002/cyto.b.21506google scholar: lookup
  40. Medica AJ, Gibb Z, Sheridan A, Harrison N, Aitken RJ. Causative Mechanisms and Functional Correlates of MTT Reduction in Stallion Spermatozoa. Reproduction (Cambridge, England) 163 (2022): 341–350.
    doi: 10.1530/repgoogle scholar: lookup
  41. Giaccagli MM, Gómez‐Elías MD, Herzfeld JD. Capacitation‐Induced Mitochondrial Activity Is Required for Sperm Fertilizing Ability in Mice by Modulating Hyperactivation. Frontiers in Cell and Developmental Biology 9 (2021): 767161.
    doi: 10.3389/fcell.2021.767161google scholar: lookup
  42. Aitken RJ, Lambourne S, Gibb Z. The John Hughes Memorial Lecture: Aspects of Sperm Physiology‐Oxidative Stress and the Functionality of Stallion Spermatozoa. Journal of Equine Veterinary Science 34, no. 1 (2014): 17–27.
    doi: 10.1016/j.jevs.2013.10.120google scholar: lookup
  43. Pommer AC, Rutllant J, Meyers SA. Phosphorylation of Protein Tyrosine Residues in Fresh and Cryopreserved Stallion Spermatozoa Under Capacitating Conditions. Biology of Reproduction 68, no. 4 (2003): 1208–1214.
    doi: 10.1095/biolreprod.102.011106google scholar: lookup
  44. Felix MR, Dobbie T, Woodward E. Equine In Vitro Fertilization With Frozen–Thawed Semen Is Associated With Shortened Pre‐Incubation Time and Modified Capacitation‐Related Changes. Biology of Reproduction 112, no. 5 (2025): 867–879.
    doi: 10.1093/biolre/ioaf043google scholar: lookup
  45. Visconti PE, Bailey JL, Moore GD, Pan D, Olds‐Clarke P, Kopf GS. Capacitation of Mouse Spermatozoa: I. Correlation Between the Capacitation State and Protein Tyrosine Phosphorylation. Development (Cambridge, England) 121, no. 4 (1995): 1129–1137.
    doi: 10.1242/dev.121.4.1129google scholar: lookup
  46. Ruiz-Díaz S, Oseguera-López I, De La Cuesta-Díaz D. The Presence of D-Penicillamine During the In Vitro Capacitation of Stallion Spermatozoa Prolongs Hyperactive-Like Motility and Allows for Sperm Selection by Thermotaxis. Animals 10, no. 9 (2020): 1–18.
    doi: 10.3390/ani10091467google scholar: lookup
  47. Balao da Silva CM, Spinaci M, Bucci D. Effect of Sex Sorting on Stallion Spermatozoa: Heterologous Oocyte Binding, Tyrosine Phosphorylation and Acrosome Reaction Assay. Animal Reproduction Science 141, no. 1–2 (2013): 68–74.
    doi: 10.1016/j.anireprosci.2013.07.008google scholar: lookup
  48. Gonzalez-Castro RA, Porflidt C, Carnevale EM. Effect of Penicillamine, Hypotaurine and Epinephrine (PHE) and pH on Stallion Sperm During In Vitro Capacitation. Journal of Equine Veterinary Science 145 (2025): 30.
    doi: 10.1016/j.jevs.2024.105289google scholar: lookup
  49. López-Úbeda R, García-Vázquez FA, Gadea J, Matás C. Oviductal Epithelial Cells Selected Boar Sperm According to Their Functional Characteristics. Asian Journal of Andrology 18 (2016): 173936.
    doi: 10.4103/1008-682x.173936google scholar: lookup
  50. Kumaresan A, Siqueira AP, Hossain MS. Quantification of Kinetic Changes in Protein Tyrosine Phosphorylation and Cytosolic Ca2+ Concentration in Boar Spermatozoa During Cryopreservation. Reproduction, Fertility, and Development 24, no. 4 (2012): 531–542.
    doi: 10.1071/rd11074google scholar: lookup
  51. Ruiz-Díaz S, Grande-Pérez S, Arce-López S, Tamargo C, Hidalgo CO, Pérez-Cerezales S. Changes in the Cellular Distribution of Tyrosine Phosphorylation and Its Relationship With the Acrosomal Exocytosis and Plasma Membrane Integrity During In Vitro Capacitation of Frozen/Thawed Bull Spermatozoa. International Journal of Molecular Sciences 21, no. 8 (2020): 2725.
    doi: 10.3390/ijms21082725google scholar: lookup
  52. Luño V, López-Úbeda R, García-Vázquez FA, Gil L, Matás C. Boar Sperm Tyrosine Phosphorylation Patterns in the Presence of Oviductal Epithelial Cells: In Vitro, Ex Vivo, and In Vivo Models. Reproduction (Cambridge, England) 146, no. 4 (2013): 315–324.
    doi: 10.1530/rep-13-0159google scholar: lookup
  53. Sutovsky P, Manandhar G, Wu A, Oko R. Interactions of Sperm Perinuclear Theca With the Oocyte: Implications for Oocyte Activation, Anti-Polyspermy Defense, and Assisted Reproduction. Microscopy Research and Technique 61, no. 4 (2003): 362–378.
    doi: 10.1002/jemt.10350google scholar: lookup
  54. Cuervo-Arango J, Claes AN, Stout TA. A Retrospective Comparison of the Efficiency of Different Assisted Reproductive Techniques in the Horse, Emphasizing the Impact of Maternal Age. Theriogenology 132 (2019): 36–44.
    doi: 10.1016/j.theriogenology.2019.04.010google scholar: lookup
  55. Catandi GD, Obeidat YM, Broeckling CD, Chen TW, Chicco AJ, Carnevale EM. Equine Maternal Aging Affects Oocyte Lipid Content, Metabolic Function and Developmental Potential. Reproduction (Cambridge, England) 161 (2021): 399–409.
    doi: 10.1530/repgoogle scholar: lookup
  56. Carnevale EM, Coutinho Da Silva MA, Panzani D, Stokes JE, Squires EL. Factors Affecting the Success of Oocyte Transfer in a Clinical Program for Subfertile Mares. Theriogenology 64, no. 3 (2005): 519–527.
    doi: 10.1016/j.theriogenology.2005.05.008google scholar: lookup
  57. Fonte JS, Alonso MA, Junior MPM. Successful Equine In Vitro Embryo Production by ICSI – Effect of Season, Mares' Age, Breed, and Phase of the Estrous Cycle on Embryo Production. Theriogenology 223 (2024): 47–52.
    doi: 10.1016/j.theriogenology.2024.04.007google scholar: lookup
  58. Catandi GD, LiPuma L, Obeidat YM. Oocyte Metabolic Function, Lipid Composition, and Developmental Potential Are Altered by Diet in Older Mares. Reproduction (Cambridge, England) 163, no. 4 (2022): 183–198.
    doi: 10.1530/rep-21-0351google scholar: lookup
  59. Frank BL, Doddman CD, Stokes JE, Carnevale EM. Association of Equine Oocyte and Cleavage Stage Embryo Morphology With Maternal Age and Pregnancy After Intracytoplasmic Sperm Injection. Reproduction, Fertility, and Development 31, no. 12 (2019): 1812–1822.
    doi: 10.1071/rd19250google scholar: lookup
  60. Claes A, Stout TAE. Success Rate in a Clinical Equine In Vitro Embryo Production Program. Theriogenology 187 (2022): 215–218.
    doi: 10.1016/j.theriogenology.2022.04.019google scholar: lookup
  61. Altermatt JL, Suh TK, Stokes JE, Carnevale EM. Effects of Age and Equine Follicle‐Stimulating Hormone (eFSH) on Collection and Viability of Equine Oocytes Assessed by Morphology and Developmental Competency After Intracytoplasmic Sperm Injection (ICSI). Reproduction, Fertility, and Development 21, no. 4 (2009): 615–623.
    doi: 10.1071/rd08210google scholar: lookup

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