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Home / Equine Research Bank / Reproduction / Temporal trends in equine sperm progressive motility: a syst...
Reproduction (Cambridge, England)2023; 165(6); M1-M10; doi: 10.1530/REP-22-0490

Temporal trends in equine sperm progressive motility: a systematic review and meta-regression.

Abstract: Adverse trends in reproductive function are a concern in humans, companion, livestock, and wildlife species. This study indicates that equine populations are at risk of a comparable decline in sperm progressive motility. There is increasing evidence reporting geographically sensitive adverse trends in human semen quality, with parallel trends observed in the dog sentinel. Despite significant economic and welfare complications associated with poor testicular function, trends in current equine populations are undetermined. Given the predictive value of sperm progressive motility (PMOT) in male factor infertility and fertilisation potential, research determining trends in this parameter is warranted. This research analysed trends in stallion sperm PMOT through systematic review and meta-regression. Using a comprehensive search strategy, Scopus, Embase (Ovid), Medline (Ovid), and VetMed (CAB direct) were scoped for eligible data. Using best practices, 230 meta-data points from 229 articles published from 1991 to 2021 were collated for meta-regression analysis. Sperm PMOT declined significantly between 1984 and 2019 (simple linear regression: b -0.340, P = 0.017; meta-regression: b -0.610, P ≤ 0.001). Overall and yearly PMOT declines were predicted at 33.51 and 0.96%, respectively (1984: 63.69 ± 5.07%; 2019: 42.35 ± 3.69%). Trends remained consistent irrespective of sensitivity analyses. Yearly and overall declines were stronger in western (yearly: 0.75%, overall: 26.29%) compared to non-western (yearly: 0.46%, overall: 10.65%) populations. Adverse trends contribute vital data to the debate surrounding declining semen quality, supporting the use of equines as novel comparative models for human reproduction. Results could have significant economic, health, and welfare consequences for equine breeding sectors. A comparable decline in human, dog, and horse sperm quality is indicative of a common environmental aetiology, indicating the need for a holistic One Health approach in determining causes and developing preventative strategies.
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Publication Date: 2023-05-02 PubMed ID: 37000597PubMed Central: PMC10235923DOI: 10.1530/REP-22-0490Google Scholar: Lookup
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  • Systematic Review
  • 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.

The research examined trends in horse sperm progressive motility over time and found a significant decrease, suggesting potential environmental causes and implications for horse breeding and human reproductive research.

Introduction and Goal

  • The researchers set out to explore trends in horse sperm progressive motility (the ability of sperm cells to move forward) which is an indicator of fertility and has implications on successful breeding.
  • Decreases in sperm quality have been observed in humans and canine species, and this study aimed to identify if a similar trend is present in horses.
  • The importance of this endeavour is underscored by it’s impact on economic and welfare issues in the equine industry, while also providing valuable data for human reproductive studies.

Methodology

  • The research was conducted using a systematic review and meta-regression methodology, which involved using extensive search strategies to gather relevant data from Scopus, Embase (Ovid), Medline (Ovid) and VetMed (CAB direct).
  • A substantial database of 230 meta-data points collected from 229 articles published between 1991 and 2021 were utilized for the meta-regression analysis.

Findings

  • Analysis showed a significant decline in sperm progressive motility in stallions between 1984 and 2019.
  • Projected overall and yearly declines were 33.51% and 0.96%, respectively.
  • These adverse trends remained consistent irrespective of sensitivity analyses, and were stronger in Western populations.
  • The data corroborates theories of decreasing semen quality across different species, supporting the potential use of horses as comparative models for studying human reproduction.

Implications and Conclusion

  • This worrying trend could have far-reaching economic and welfare impacts on the equine breeding industry.
  • The presence of a similar decline across humans, dogs, and horses suggests a common environmental factor which should be further investigated to develop preventative strategies.
  • This research further highlights the importance of adopting a comprehensive ‘One Health’ approach – viewing human and animal health as interconnected, in studying causes and solutions for declining reproductive health.

Cite This Article

APA
Harris IT, Maddock C, Farnworth M, Nankervis K, Perrett J, Pyatt AZ, Blanchard RN. (2023). Temporal trends in equine sperm progressive motility: a systematic review and meta-regression. Reproduction, 165(6), M1-M10. https://doi.org/10.1530/REP-22-0490

Publication

Reproduction (Cambridge, England)
ISSN: 1741-7899
NlmUniqueID: 100966036
Country: England
Language: English
Volume: 165
Issue: 6
Pages: M1-M10

Researcher Affiliations

Harris, I T
  • HE Equine, Hartpury University and Hartpury College, Hartpury House, Gloucester, UK.
Maddock, C
  • HE Equine, Hartpury University and Hartpury College, Hartpury House, Gloucester, UK.
Farnworth, M
  • The Jeanne Marchig International Centre for Animal Welfare Education, The Royal (Dick) School of Veterinary Studies, Midlothian, UK.
Nankervis, K
  • HE Equine, Hartpury University and Hartpury College, Hartpury House, Gloucester, UK.
Perrett, J
  • International Office, Veterinary Medicines Directorate, Addlestone, UK.
Pyatt, A Z
  • International Office, Veterinary Medicines Directorate, Addlestone, UK.
Blanchard, R N
  • School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Loughborough, UK.

MeSH Terms

  • Male
  • Horses
  • Animals
  • Humans
  • Dogs
  • Semen Analysis / veterinary
  • Semen
  • Sperm Motility
  • Spermatozoa
  • Infertility, Male
  • Sperm Count

Conflict of Interest Statement

The authors declare that there is no conflict of interest.

References

This article includes 59 references
  1. Aurich J, Kuhl J, Tichy A, Aurich C. Efficiency of Semen Cryopreservation in Stallions.. Animals (Basel) 2020 Jun 13;10(6).
    doi: 10.3390/ani10061033pmc: PMC7341245pubmed: 32545785google scholar: lookup
  2. Borenstein M, Hedges LV, Higgins JPT, Rothstein HR. Introduction to meta-analysis. .
  3. Boulicault M, Perret M, Galka J, Borsa A, Gompers A, Reiches M, Richardson S. The future of sperm: a biovariability framework for understanding global sperm count trends.. Hum Fertil (Camb) 2022 Dec;25(5):888-902.
    doi: 10.1080/14647273.2021.1917778pubmed: 33969777google scholar: lookup
  4. Bramer WM, Rethlefsen ML, Kleijnen J, Franco OH. Optimal database combinations for literature searches in systematic reviews: a prospective exploratory study.. Syst Rev 2017 Dec 6;6(1):245.
    doi: 10.1186/s13643-017-0644-ypmc: PMC5718002pubmed: 29208034google scholar: lookup
  5. Cabrera T, Ramires-Neto C, Belaz KRA, Freitas-Dell'aqua CP, Zampieri D, Tata A, Eberlin MN, Alvarenga MA, Souza FF. Influence of spermatozoal lipidomic profile on the cryoresistance of frozen spermatozoa from stallions.. Theriogenology 2018 Mar 1;108:161-166.
    doi: 10.1016/j.theriogenology.2017.11.025pubmed: 29223009google scholar: lookup
  6. Campbell ML, Sandøe P. Welfare in horse breeding.. Vet Rec 2015 Apr 25;176(17):436-40.
    doi: 10.1136/vr.102814pmc: PMC4431322pubmed: 25908746google scholar: lookup
  7. Carlsen E, Giwercman A, Keiding N, Skakkebaek NE. Evidence for decreasing quality of semen during past 50 years.. BMJ 1992 Sep 12;305(6854):609-13.
    doi: 10.1136/bmj.305.6854.609pmc: PMC1883354pubmed: 1393072google scholar: lookup
  8. Castaneda C, Juras R, Kjöllerström J, Hernandez Aviles C, Teague SR, Love CC, Cothran EG, Varner DD, Raudsepp T. Thoroughbred stallion fertility is significantly associated with FKBP6 genotype but not with inbreeding or the contribution of a leading sire.. Anim Genet 2021 Dec;52(6):813-823.
    doi: 10.1111/age.13142pubmed: 34610162google scholar: lookup
  9. . Guidelines for authors – environmental evidence. .
  10. Chang S, Nazem T, Gounko D, Lee J, Bar-Chama N, Shamonki J, Antonelli C, Copperman A. Eleven-year longitudinal study of US sperm donors demonstrates declining sperm count and motility. Fertility and Sterility 110e54–e55.
    doi: 10.1016/j.fertnstert.2018.07.170google scholar: lookup
  11. Colenbrander B, Gadella BM, Stout TA. The predictive value of semen analysis in the evaluation of stallion fertility.. Reprod Domest Anim 2003 Aug;38(4):305-11.
    doi: 10.1046/j.1439-0531.2003.00451.xpubmed: 12887569google scholar: lookup
  12. Dcunha R, Hussein RS, Ananda H, Kumari S, Adiga SK, Kannan N, Zhao Y, Kalthur G. Current Insights and Latest Updates in Sperm Motility and Associated Applications in Assisted Reproduction.. Reprod Sci 2022 Jan;29(1):7-25.
    doi: 10.1007/s43032-020-00408-ypmc: PMC7721202pubmed: 33289064google scholar: lookup
  13. Dini P, Bartels T, Revah I, Claes AN, Stout TAE, Daels P. A retrospective study on semen quality parameters from four different Dutch horse breeds with different levels of inbreeding.. Theriogenology 2020 Nov;157:18-23.
    doi: 10.1016/j.theriogenology.2020.07.017pubmed: 32768723google scholar: lookup
  14. Ducro BJ, Windig J, Hellinga I, Bovenhuis H. Genetic diversity and measures to reduce inbreeding in Friesian Horses. In Proceedings, 10th World Congress of Genetics Applied to Livestock Production, pp. 797–797.
  15. Ebel F, Vallejos A, Gajardo G, Ulloa O, Clavel E, Rodríguez-Gil JE, Ramírez-Reveco A. Semen quality and freezability analysis during breeding and non-breeding seasons in heavy draft stallions in southern Chile.. Andrologia 2020 Dec;52(11):e13797.
    doi: 10.1111/and.13797pubmed: 32870570google scholar: lookup
  16. Feferkorn I, Azani L, Kadour-Peero E, Hizkiyahu R, Shrem G, Salmon-Divon M, Dahan MH. Geographic variation in semen parameters from data used for the World Health Organization semen analysis reference ranges.. Fertil Steril 2022 Sep;118(3):475-482.
    doi: 10.1016/j.fertnstert.2022.05.037pubmed: 35750517google scholar: lookup
  17. Fisch H. Declining worldwide sperm counts: disproving a myth.. Urol Clin North Am 2008 May;35(2):137-46, vii.
    doi: 10.1016/j.ucl.2008.01.001pubmed: 18423235google scholar: lookup
  18. Florez-Rodriguez SA, de Arruda RP, Alves MBR, Affonso FJ, Carvalho HF, Lemes KM, Lançoni R, de Andrade AFC, Celeghini ECC. Morphofunctional characterization of cooled sperm with different extenders to use in equine-assisted reproduction. Journal of Equine Veterinary Science 34 911–917.
    doi: 10.1016/j.jevs.2014.04.007google scholar: lookup
  19. Griffin RA, Swegen A, Baker M, Aitken RJ, Skerrett-Byrne DA, Silva Rodriguez A, Martín-Cano FE, Nixon B, Peña FJ, Delehedde M, Sergeant N, Gibb Z. Mass spectrometry reveals distinct proteomic profiles in high- and low-quality stallion spermatozoa.. Reproduction 2020 Nov;160(5):695-707.
    doi: 10.1530/REP-20-0284pubmed: 32805711google scholar: lookup
  20. Grindlay DJ, Brennan ML, Dean RS. Searching the veterinary literature: a comparison of the coverage of veterinary journals by nine bibliographic databases.. J Vet Med Educ 2012 Winter;39(4):404-12.
    doi: 10.3138/jvme.1111.109Rpubmed: 23187034google scholar: lookup
  21. Gusenbauer M, Haddaway NR. Which academic search systems are suitable for systematic reviews or meta-analyses? Evaluating retrieval qualities of Google Scholar, PubMed, and 26 other resources.. Res Synth Methods 2020 Mar;11(2):181-217.
    doi: 10.1002/jrsm.1378pmc: PMC7079055pubmed: 31614060google scholar: lookup
  22. Haddaway NR, Macura B, Whaley P, Pulin AS. ROSES Flow Diagram for Systematic Reviews. Version 1.0.
    doi: 10.6084/m9.figshare.6085940.v2google scholar: lookup
  23. Haddaway NR, Macura B, Whaley P, Pulin AS. ROSES Reporting standards for Systematic Evidence Syntheses: pro forma, flow-diagram and descriptive summary of the plan and conduct of environmental systematic reviews and systematic maps. Environmental Evidence 7 1–8.
    doi: 10.1186/s13750-018-0121-7google scholar: lookup
  24. Harris I, Lea R, Sumner R. Exposure to environmental contaminants and the impact on reproductive health. Clinical Theriogenology 14.
    doi: 10.58292/therio.v14i3.9140google scholar: lookup
  25. Hu YA, Lu JC, Shao Y, Huang YF, Lü NQ. Comparison of the semen analysis results obtained from two branded computer-aided sperm analysis systems.. Andrologia 2013 Oct;45(5):315-8.
    doi: 10.1111/and.12010pubmed: 22928934google scholar: lookup
  26. Johnson SL, Dunleavy J, Gemmell NJ, Nakagawa S. Consistent age-dependent declines in human semen quality: a systematic review and meta-analysis.. Ageing Res Rev 2015 Jan;19:22-33.
    doi: 10.1016/j.arr.2014.10.007pubmed: 25462195google scholar: lookup
  27. Kowalczyk A, Czerniawska-Piątkowska E, Kuczaj M. Factors Influencing the Popularity of Artificial Insemination of Mares in Europe.. Animals (Basel) 2019 Jul 19;9(7).
    doi: 10.3390/ani9070460pmc: PMC6680944pubmed: 31331026google scholar: lookup
  28. Kumar N, Singh AK. Trends of male factor infertility, an important cause of infertility: A review of literature.. J Hum Reprod Sci 2015 Oct-Dec;8(4):191-6.
    doi: 10.4103/0974-1208.170370pmc: PMC4691969pubmed: 26752853google scholar: lookup
  29. Lea RG, Byers AS, Sumner RN, Rhind SM, Zhang Z, Freeman SL, Moxon R, Richardson HM, Green M, Craigon J, England GC. Environmental chemicals impact dog semen quality in vitro and may be associated with a temporal decline in sperm motility and increased cryptorchidism.. Sci Rep 2016 Aug 9;6:31281.
    doi: 10.1038/srep31281pmc: PMC4977511pubmed: 27503122google scholar: lookup
  30. Levine H, Jørgensen N, Martino-Andrade A, Mendiola J, Weksler-Derri D, Jolles M, Pinotti R, Swan SH. Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries.. Hum Reprod Update 2023 Mar 1;29(2):157-176.
    doi: 10.1093/humupd/dmac035pubmed: 36377604google scholar: lookup
  31. Levine H, Jørgensen N, Martino-Andrade A, Mendiola J, Weksler-Derri D, Mindlis I, Pinotti R, Swan SH. Temporal trends in sperm count: a systematic review and meta-regression analysis.. Hum Reprod Update 2017 Nov 1;23(6):646-659.
    doi: 10.1093/humupd/dmx022pmc: PMC6455044pubmed: 28981654google scholar: lookup
  32. Love CC, Noble JK, Standridge SA, Bearden CT, Blanchard TL, Varner DD, Cavinder CA. The relationship between sperm quality in cool-shipped semen and embryo recovery rate in horses.. Theriogenology 2015 Dec;84(9):1587-1593.e4.
    doi: 10.1016/j.theriogenology.2015.08.008pubmed: 26363735google scholar: lookup
  33. McGivney BA, Han H, Corduff LR, Katz LM, Tozaki T, MacHugh DE, Hill EW. Genomic inbreeding trends, influential sire lines and selection in the global Thoroughbred horse population.. Sci Rep 2020 Jan 16;10(1):466.
    doi: 10.1038/s41598-019-57389-5pmc: PMC6965197pubmed: 31949252google scholar: lookup
  34. Merzenich H, Zeeb H, Blettner M. Decreasing sperm quality: a global problem?. BMC Public Health 2010 Jan 19;10:24.
    doi: 10.1186/1471-2458-10-24pmc: PMC2818620pubmed: 20085639google scholar: lookup
  35. Multigner L, Magistrini M, Ducot B, Spira A. Secular sperm trends in stallions between 1981 and 1996.. J Androl 1999 Nov-Dec;20(6):763-8.
    doi: 10.1002/j.1939-4640.1999.tb03383.xpubmed: 10591616google scholar: lookup
  36. Multigner L, Magistrini M, Ducot B, Spira A. [Environment and secular sperm trend. Stallion's semen quality during the last two decades].. Rev Epidemiol Sante Publique 2000 Aug;48 Suppl 2:2S72-8.
    pubmed: 10992112
  37. Ortiz-Rodriguez JM, Martín-Cano FE, Ortega-Ferrusola C, Masot J, Redondo E, Gázquez A, Gil MC, Aparicio IM, Rojo-Domínguez P, Tapia JA, Rodriguez-Martínez H, Peña FJ. The incorporation of cystine by the soluble carrier family 7 member 11 (SLC7A11) is a component of the redox regulatory mechanism in stallion spermatozoa†.. Biol Reprod 2019 Jul 1;101(1):208-222.
    doi: 10.1093/biolre/ioz069pubmed: 30998234google scholar: lookup
  38. Pacey AA. Are sperm counts declining? Or did we just change our spectacles?. Asian J Androl 2013 Mar;15(2):187-90.
    doi: 10.1038/aja.2012.165pmc: PMC3739163pubmed: 23353722google scholar: lookup
  39. Parlevliet JM, Kemp B, Colenbrander B. Reproductive characteristics and semen quality in maiden Dutch Warmblood stallions.. J Reprod Fertil 1994 May;101(1):183-7.
    doi: 10.1530/jrf.0.1010183pubmed: 8064679google scholar: lookup
  40. Perrett J, Harris IT, Maddock C, Farnworth M, Pyatt AZ, Sumner RN. Systematic Analysis of Breed, Methodological, and Geographical Impact on Equine Sperm Progressive Motility.. Animals (Basel) 2021 Oct 29;11(11).
    doi: 10.3390/ani11113088pmc: PMC8614490pubmed: 34827820google scholar: lookup
  41. Pirosanto Y, Molina A, Valera M, Dorado J, Terán E, Azcona F, Sebastian DP. Increased inbreeding levels negatively affect sperm kinetics and motility in Purebred Spanish horses. Reproduction, Fertility and Development 33 116–116.
    doi: 10.1071/RDv33n2Ab17google scholar: lookup
  42. Pirosanto Y, Valera M, Molina A, Dorado J, Demyda-Peyrás S. Sperm quality of Pure Spanish stallions is affected by inbreeding coefficient and age. Reproduction, Fertility and Development 32 137–137.
    doi: 10.1071/RDv32n2Ab23google scholar: lookup
  43. Setchell BP. Sperm counts in semen of farm animals 1932-1995.. Int J Androl 1997 Aug;20(4):209-14.
    doi: 10.1046/j.1365-2605.1997.00054.xpubmed: 9401823google scholar: lookup
  44. Shakeel M, Jung H, Yoon D, Yoon M. Seasonal changes in the expression of molecular markers of stallion germ cells.. J Equine Vet Sci 2022 Nov;118:104109.
    doi: 10.1016/j.jevs.2022.104109pubmed: 36029943google scholar: lookup
  45. Sharpe RM. Environmental/lifestyle effects on spermatogenesis.. Philos Trans R Soc Lond B Biol Sci 2010 May 27;365(1546):1697-712.
    doi: 10.1098/rstb.2009.0206pmc: PMC2871918pubmed: 20403879google scholar: lookup
  46. Simon L, Lewis SE. Sperm DNA damage or progressive motility: which one is the better predictor of fertilization in vitro?. Syst Biol Reprod Med 2011 Jun;57(3):133-8.
    doi: 10.3109/19396368.2011.553984pubmed: 21299480google scholar: lookup
  47. Skakkebaek NE, Rajpert-De Meyts E, Buck Louis GM, Toppari J, Andersson AM, Eisenberg ML, Jensen TK, Jørgensen N, Swan SH, Sapra KJ, Ziebe S, Priskorn L, Juul A. Male Reproductive Disorders and Fertility Trends: Influences of Environment and Genetic Susceptibility.. Physiol Rev 2016 Jan;96(1):55-97.
    doi: 10.1152/physrev.00017.2015pmc: PMC4698396pubmed: 26582516google scholar: lookup
  48. Sumner RN, Byers A, Zhang Z, Agerholm JS, Lindh L, England GCW, Lea RG. Environmental chemicals in dog testes reflect their geographical source and may be associated with altered pathology.. Sci Rep 2021 Apr 1;11(1):7361.
    doi: 10.1038/s41598-021-86805-ypmc: PMC8016893pubmed: 33795811google scholar: lookup
  49. Sumner RN, Harris IT, Van der Mescht M, Byers A, England GCW, Lea RG. The dog as a sentinel species for environmental effects on human fertility.. Reproduction 2020 May;159(6):R265-R276.
    doi: 10.1530/REP-20-0042pubmed: 32213655google scholar: lookup
  50. Swan SH. Semen quality in fertile US men in relation to geographical area and pesticide exposure.. Int J Androl 2006 Feb;29(1):62-8; discussion 105-8.
    doi: 10.1111/j.1365-2605.2005.00620.xpubmed: 16466525google scholar: lookup
  51. Swan SH, Elkin EP, Fenster L. The question of declining sperm density revisited: an analysis of 101 studies published 1934-1996.. Environ Health Perspect 2000 Oct;108(10):961-6.
    doi: 10.1289/ehp.00108961pmc: PMC1240129pubmed: 11049816google scholar: lookup
  52. Thompson SG, Higgins JP. How should meta-regression analyses be undertaken and interpreted?. Stat Med 2002 Jun 15;21(11):1559-73.
    doi: 10.1002/sim.1187pubmed: 12111920google scholar: lookup
  53. Tiegs AW, Landis J, Garrido N, Scott RT Jr, Hotaling JM. Total Motile Sperm Count Trend Over Time: Evaluation of Semen Analyses From 119,972 Men From Subfertile Couples.. Urology 2019 Oct;132:109-116.
    doi: 10.1016/j.urology.2019.06.038pubmed: 31326545google scholar: lookup
  54. Tong N, Witherspoon L, Dunne C, Flannigan R. Global decline of male fertility: fact or fiction? A broad summary of the published evidence on sperm-count and fertility trends. British Columbia Medical Journal 64 126–130.
  55. van Eldik P, van der Waaij EH, Ducro B, Kooper AW, Stout TA, Colenbrander B. Possible negative effects of inbreeding on semen quality in Shetland pony stallions.. Theriogenology 2006 Apr 1;65(6):1159-70.
    doi: 10.1016/j.theriogenology.2005.08.001pubmed: 16165199google scholar: lookup
  56. van Os JL, de Vries MJ, den Daas NH, Kaal Lansbergen LM. Long-term trends in sperm counts of dairy bulls.. J Androl 1997 Nov-Dec;18(6):725-31.
    pubmed: 9432146
  57. Wahl RL, Reif JS. Temporal trends in bull semen quality: a comparative model for human health?. Environ Res 2009 Apr;109(3):273-80.
    doi: 10.1016/j.envres.2008.10.012pubmed: 19181314google scholar: lookup
  58. Whitesell K, Stefanovski D, McDonnell S, Turner R. Evaluation of the effect of laboratory methods on semen analysis and breeding soundness examination (BSE) classification in stallions.. Theriogenology 2020 Jan 15;142:67-76.
    doi: 10.1016/j.theriogenology.2019.09.035pubmed: 31581045google scholar: lookup
  59. Xue T, Zhu T. Increment of ambient exposure to fine particles and the reduced human fertility rate in China, 2000-2010.. Sci Total Environ 2018 Nov 15;642:497-504.
    doi: 10.1016/j.scitotenv.2018.06.075pubmed: 29908508google scholar: lookup

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