FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Trop Anim Health Prod / Reproductive characteristics of stallions during the breedin...
Tropical animal health and production2012; 44(7); 1703-1707; doi: 10.1007/s11250-012-0127-z

Reproductive characteristics of stallions during the breeding and non-breeding season in a tropical region.

Abstract: The objective of this study was to investigate reproductive characteristics of stallions at a tropical zone in the breeding and non-breeding seasons. The following parameters were assessed: testicular volume; semen quality; and serum concentrations of LH, FSH, and testosterone; in addition to the percentages of germ cells and proportions of germ cells/Sertoli cells by testicular cytology in stallions. Semen was collected from eight adult stallions twice a week during a 12-week period in both seasons (6 weeks before and 6 weeks after the summer and winter solstices). Jugular blood samples were collected periodically for hormone analysis by radioimmunoassay during the same periods. Testicular measures and cytological samples were taken at the end of each period. Mean concentration of testosterone was significantly higher (P = 0.04) during the breeding season and the proportion of Sertoli cells/100 germ cells in cytological smears was significantly lower during the breeding season (P = 0.0001). Effects of season were not significant either for testicular volume or for any semen parameter (P > 0.05). Seasonal changes in the mean concentrations of LH and FSH were not observed (P > 0.05). There were also no significant differences in the mean percentages of germ cell types between both seasons (P > 0.05). Lack of seasonal differences in the testicular volume and semen parameters of tropical stallions are probably due to the small variation in duration of natural light between the observed periods, slightly under 3 h.
Get Full Text
Publication Date: 2012-04-01 PubMed ID: 22466990DOI: 10.1007/s11250-012-0127-zGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article
  • Research Support
  • Non-U.S. Gov't

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.

This research study investigates the reproductive characteristics of stallions in tropical climates during breeding and non-breeding seasons. The study found significant seasonal changes in testosterone levels and the proportion of Sertoli cells compared to germ cells, but did not find notable changes in other parameters such as testicular volume and semen quality.

Study Objective and Methods

  • The aim of this study was to understand the reproductive characteristics of stallions in a tropical region, tracking changes between breeding and non-breeding seasons.
  • The researchers measured several parameters: testicular volume, semen quality, and serum concentrations of LH, FSH, and testosterone. They also looked at the percentages and proportions of germ cells to Sertoli cells by carrying out testicular cytology in stallions.
  • Eight adult stallions were involved in the study. Semen was collected from these stallions twice a week over a 12-week period. This period included six weeks before and six weeks after both the summer and winter solstices.
  • Jugular blood samples were periodically collected for hormone analysis by radioimmunoassay during the same periods. Testicular measures and cytological samples were collected at the end of each period.

Findings

  • The researchers observed a significant difference in the mean concentration of testosterone during the breeding season, which was higher (P = 0.04).
  • The proportion of Sertoli cells per 100 germ cells in cytological smears was significantly lower during the breeding season (P = 0.0001).
  • However, the effects of the season were not significant either for testicular volume or for any semen parameter (P > 0.05).
  • No seasonal changes were observed in the mean concentrations of LH and FSH (P > 0.05).
  • There were also no significant differences in the mean percentages of germ cell types between both seasons (P > 0.05).

Conclusion

  • The study concluded that the lack of seasonal differences in the testicular volume and semen parameters of tropical stallions might be due to the minimal variation in the duration of natural light between the observed periods, which was slightly less than 3 hours.

Cite This Article

APA
Leme DP, Papa FO, Roser JF. (2012). Reproductive characteristics of stallions during the breeding and non-breeding season in a tropical region. Trop Anim Health Prod, 44(7), 1703-1707. https://doi.org/10.1007/s11250-012-0127-z

Publication

Tropical animal health and production
ISSN: 1573-7438
NlmUniqueID: 1277355
Country: United States
Language: English
Volume: 44
Issue: 7
Pages: 1703-1707

Researcher Affiliations

Leme, Denise Pereira
  • Laboratório de Etologia Aplicada e Bem-estar Animal, Departamento de Zootecnia e Desenvolvimento Rural, Universidade Federal de Santa Catarina, Rodovia Admar Gonzaga, 1346, Itacorubi, Florianópolis, 88.034-001, SC, Brazil. denise.leme@ufsc.br
Papa, Frederico Ozanam
    Roser, Janet F

      MeSH Terms

      • Animals
      • Brazil
      • Follicle Stimulating Hormone / blood
      • Horses / anatomy & histology
      • Horses / physiology
      • Luteinizing Hormone / blood
      • Male
      • Organ Size
      • Seasons
      • Semen / physiology
      • Semen Analysis / veterinary
      • Sertoli Cells / cytology
      • Sperm Count / veterinary
      • Spermatozoa / cytology
      • Testis / anatomy & histology
      • Testis / cytology
      • Testis / physiology
      • Testosterone / blood
      • Tropical Climate

      References

      This article includes 16 references
      1. Byers SW, Dowsett KF, Glover TD. Seasonal and circadian changes of testosterone levels in the peripheral blood plasma of stallions and their relation to semen quality.. J Endocrinol 1983 Oct;99(1):141-50.
        pubmed: 6631304doi: 10.1677/joe.0.0990141google scholar: lookup
      2. Johnson L. Increased daily sperm production in the breeding season of stallions is explained by an elevated population of spermatogonia.. Biol Reprod 1985 Jun;32(5):1181-90.
        pubmed: 4016174doi: 10.1095/biolreprod32.5.1181google scholar: lookup
      3. Clay CM, Clay JN. Endocrine and testicular changes associated with season, artificial photoperiod, and the peri-pubertal period in stallions.. Vet Clin North Am Equine Pract 1992 Apr;8(1):31-56.
        pubmed: 1576553doi: 10.1016/s0749-0739(17)30465-0google scholar: lookup
      4. van der Holst W. A study of the morphology of stallion semen during the breeding and non-breeding seasons.. J Reprod Fertil Suppl 1975 Oct;(23):87-9.
        pubmed: 1060878
      5. Pickett BW, Sullivan JJ, Seidel GE Jr. Reproductive physiology of the stallion. V. Effect of frequency of ejaculation on seminal characteristics and spermatozoal output.. J Anim Sci 1975 May;40(5):917-23.
        pubmed: 236991doi: 10.2527/jas1975.405917xgoogle scholar: lookup
      6. Thompson DL Jr, Pickett BW, Berndtson WE, Voss JL, Mett TM. Reproductive physiology of the stallion. VIII. Artificial photoperiod, collection interval and seminal characteristics, sexual behavior and concentrations of LH and testosterone in serum.. J Anim Sci 1977 Apr;44(4):656-64.
        pubmed: 853023doi: 10.2527/jas1977.444656xgoogle scholar: lookup
      7. Clay CM, Squires EL, Amann RP, Nett TM. Influences of season and artificial photoperiod on stallions: luteinizing hormone follicle-stimulating hormone and testosterone.. J Anim Sci 1988 May;66(5):1246-55.
        pubmed: 3135286doi: 10.2527/jas1988.6651246xgoogle scholar: lookup
      8. Hoffmann B, Landeck A. Testicular endocrine function, seasonality and semen quality of the stallion.. Anim Reprod Sci 1999 Oct 31;57(1-2):89-98.
        pubmed: 10565441doi: 10.1016/s0378-4320(99)00050-0google scholar: lookup
      9. Berndtson WE, Pickett BW, Nett TM. Reproductive physiology of the stallion. IV. Seasonal changes in the testosterone concentration of peripheral plasma.. J Reprod Fertil 1974 Jul;39(1):115-8.
        pubmed: 4854121doi: 10.1530/jrf.0.0390115google scholar: lookup
      10. Clay CM, Squires EL, Amann RP, Pickett BW. Influences of season and artificial photoperiod on stallions: testicular size, seminal characteristics and sexual behavior.. J Anim Sci 1987 Feb;64(2):517-25.
        pubmed: 3558153doi: 10.2527/jas1987.642517xgoogle scholar: lookup
      11. Thompson DL Jr, St George RL, Jones LS, Garza F Jr. Patterns of secretion of luteinizing hormone, follicle stimulating hormone and testosterone in stallions during the summer and winter.. J Anim Sci 1985 Mar;60(3):741-8.
        pubmed: 3921510doi: 10.2527/jas1985.603741xgoogle scholar: lookup
      12. Leme DP, Papa FO. Cytological identification and quantification of testicular cell types using fine needle aspiration in horses.. Equine Vet J 2000 Sep;32(5):444-6.
        pubmed: 11037268doi: 10.2746/042516400777591156google scholar: lookup
      13. Roser JF, Hughes JP. Seasonal effects on seminal quality, plasma hormone concentrations, and GnRH-induced LH response in fertile and subfertile stallions.. J Androl 1992 May-Jun;13(3):214-23.
        pubmed: 1318293
      14. Janett F, Thun R, Niederer K, Burger D, Hässig M. Seasonal changes in semen quality and freezability in the Warmblood stallion.. Theriogenology 2003 Aug;60(3):453-61.
        pubmed: 12763159doi: 10.1016/s0093-691x(03)00046-3google scholar: lookup
      15. Wrench N, Pinto CR, Klinefelter GR, Dix DJ, Flowers WL, Farin CE. Effect of season on fresh and cryopreserved stallion semen.. Anim Reprod Sci 2010 Jun;119(3-4):219-27.
        pubmed: 20227205doi: 10.1016/j.anireprosci.2010.02.007google scholar: lookup
      16. Magistrini M, Chanteloube P, Palmer E. Influence of season and frequency of ejaculation on production of stallion semen for freezing.. J Reprod Fertil Suppl 1987;35:127-33.
        pubmed: 3479568

      Citations

      This article has been cited 1 times.
      1. Kandiel MMM, El Khawagah ARM. Evaluation of semen characteristics, oxidative stress, and biochemical indices in Arabian horses of different ages during the hot summer season. Iran J Vet Res 2018 Fall;19(4):270-275.
        pubmed: 30774667
      Subscribe to our newsletter
      Join 99,357 horse owners like you who receive our email updates on horse health and nutrition.