FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Acta Vet Scand / Onset of luteal activity in non-foaling mares during the ear...
Acta veterinaria Scandinavica1991; 32(3); 319-325; doi: 10.1186/BF03546961

Onset of luteal activity in non-foaling mares during the early breeding season in Finland.

Abstract: The luteal activity in mares was studied in the Equine Research Station (ERS) and in trotting stables (TS) in South-Finland. The mares were Standardbreeds in the TS and mainly Finnhorses in the ERS. Between January and June blood was collected once a week for serum progesterone determinations. The mares in the ERS were distributed in 1 of 3 groups: three-years old not yet in training (N = 38), brood mares (N = 21) and mares in training (N = 47). A 4th group was the mares in training in the trotting stables (N = 73). Every 5th mare in the ERS and every 4th mare in the trotting stables were cycling already at the beginning of the year. Onset of luteal activity in anoestrous mares was most common in the middle of May. Over 95% of the mares were cycling at the beginning of June. In the ERS 40% of the Finnhorse mares in training were cycling through the winter. The three-years old and the brood mares were all anoestrous during winter. They started to cycle on average before the middle of May. Anoestrous training mares started before the middle of April. Anoestrous Finnhorse mares began to cycle later than warm blooded mares in all of the groups studied. Mares which had foaled the previous year were more often anoestrous during the winter than dry mares. The time of year when cycling began in a particular mare tended to be the same from year to year (p less than 0.01). Lutealfunktionen hos ston undersöktes vid Hästforskningsstationen (HF) samt vid någon travcentral i södra Finland (TC). Stona vid TC utgjordes av varmblodiga travhästar och vid HF av finnhästar. Progesteron i serum bestämdes en gång i veckan under tiden januari-juni. Stona vid HF indelades i 3 grupper: treåriga ston som ännu inte börjat tränas (N = 38), fölston (N = 21) och ston i träning (N = 47). Den 4. gruppen utgjordes av ston i träning vid TC (N = 73). Brunstcykeln var igång hos vart femte sto i HF-gruppen och hos vart fjärde sto i TC-gruppen redan i början av året. Lutealfasen hos de anöstrala stona började oftast i mitten av maj. Brunstcykeln var igång hos mer än 95 % av stona i början av juni. Fyrtio procent av de finnhäststona i träning hade brunstcykel under hela vintern, medan stona i de 2 andra grupperna vid HF var anöstrala hela vintern. Deras brunstcykel började i medeltal före mitten av maj, medan första brunstcykeln hos de anöstrala stona i träning inleddes före mitten av april. Av de olika grupper var de anöstrala finnhäststona sist med igångsättningen av sin brunstcykel. Vin-teranöstrus forekom oftare hos ston som hade fölat under foregående år än hos sådana som inte fölat. Tidpunkten på årstiden då brunstcykeln började tenderade att vara den samma hos de individuella stona under flera år (p < 0.01).
Get Full Text
Publication Date: 1991-01-01 PubMed ID: 1814181PubMed Central: PMC8127913DOI: 10.1186/BF03546961Google 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

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 onset of luteal activity in non-foaling (non-pregnant) mares during the early breeding season in Finland. The findings suggest that over 95% of mares start cycling at the beginning of June, while onset of activity among anoestrus mares is most common in mid-May.

Research Setting and Methodology

  • The study was conducted at the Equine Research Station (ERS) and trotting stables in South Finland.
  • The horses studied were mostly Standardbreds in the trotting stables and Finnhorses at the ERS.
  • Blood samples were collected weekly between January and June to determine serum progesterone levels, which indicate luteal activity.
  • The mares in the ERS were divided into three groups: three-year-olds not yet in training (38 mares), brood mares (21 mares), and mares in training (47 mares). A fourth group comprised mares in training at the trotting stables (73 mares).

Luteal Activity Results

  • At the start of the year, every 5th mare at ERS and every 4th mare in the trotting stables were already cycling.
  • In the middle of May, onset of luteal activity was most common among anoestrus mares (mares not in oestrus or “heat”).
  • By the start of June, over 95% of the mares had begun cycling.

Luteal Activity Among Specific Groups

  • 40% of the Finnhorse mares in training at the ERS cycled through the winter.
  • All the three-year olds and brood mares at ERS were anoestrus during winter, but started to cycle on average before mid-May.
  • Anoestrus mares in training started their cycle before mid-April.
  • Anoestrus Finnhorse mares began to cycle later than warm-blooded mares in all groups studied.
  • Mares that had foaled the previous year were more frequently anoestrus during winter than mares that had not foaled.
  • The timing of the onset of cycling in a specific mare tended to be consistent from year to year.

Overall, the study provides insights into luteal activity patterns in non-foaling mares, which may inform breeding and mare management strategies.

Cite This Article

APA
Koskinen E, Katila T. (1991). Onset of luteal activity in non-foaling mares during the early breeding season in Finland. Acta Vet Scand, 32(3), 319-325. https://doi.org/10.1186/BF03546961

Publication

Acta veterinaria Scandinavica
ISSN: 0044-605X
NlmUniqueID: 0370400
Country: England
Language: English
Volume: 32
Issue: 3
Pages: 319-325

Researcher Affiliations

Koskinen, E
  • Agricultural Research Centre, Equine Research Station, Ypäjä, Finland.
Katila, T

    MeSH Terms

    • Age Factors
    • Anestrus / physiology
    • Animals
    • Breeding
    • Corpus Luteum / physiology
    • Female
    • Finland
    • Horses / physiology
    • Seasons

    References

    This article includes 17 references
    1. Arthur GH. An analysis of the reproductive function of mares based on postmortem examination.. Vet. Rec. 1958;70:682–686.
    2. David JSE. A survey of eggs in the oviducts of mares.. J. Reprod. Fertil. 1975, Suppl. 23, 513–517.
      pubmed: 1060834
    3. Ginther OJ. Occurrence of anestrus, estrus, diestrus and ovulation over a 12 month period in mares.. Am. J. vet. Res. 1974;35:1173–1179.
      pubmed: 4473070
    4. Ginther OJ. Reproductive biology of the mare. Basic and applied aspects.. Equiservices, Cross Plains, WI, USA, 1979, pp 83–106.
    5. Kenney RM, Ganjam VK, Bergman R V. Non-infectious breeding problems in mares.. Veterinary Scope (Kalamazoo, MI) 1975;19:16–24.
    6. King SS, Nequin LG, Drake S, Hebner TS, Roser JF, Ewans JW. Progesterone levels correlate with impending anestrus in the mare.. Eq. Vet. Sci. 1988;8:109–111.
      doi: 10.1016/S0737-0806(88)80029-7google scholar: lookup
    7. Neely DP. Reproductive endocrinology and fertility in the mare.. In: Neely DP, Liu IKM, Hillman RB, Hughes JP (eds.). Equine Reproduction. Veterinary Learning Systems Co., Inc. Publishers, USA 1983, pp 18.
    8. Nyborg RG. Ovulations uregelmæssigheder og et uheldigt bedaeknings- og afprøvningssystem som årsag til ufrugtbarhed hos hopper. (Ovulation irregulavities, service periods and infertility in mares).. Nord. Vet.-Med. 1953;5:473–538.
    9. Osborne VE. Analysis of the pattern of ovulation as it occurs in the annual reproductive cycle of the mare in Australia.. Aust. vet. J. 1966;42:149–154.
      doi: 10.1111/j.1751-0813.1966.tb16013.xpubmed: 5954481google scholar: lookup
    10. Palmer E, Jousset B. Urinary oestrogen and plasma progesterone levels in non-pregnant mares.. J. Reprod. Fertil. 1975, Suppl. 23, 213–221.
      pubmed: 1060781
    11. Palmer E. Control of the oestrous cycle of the mare.. J. Reprod. Fertil. 1978;54:495–505.
      doi: 10.1530/jrf.0.0540495pubmed: 364055google scholar: lookup
    12. Palmer E, Driancourt MA, Ortavent R. Photoperiodic stimulation of the mare during winter anestrus.. J. Reprod. Fertil. 1982, Suppl. 32, 275–282.
      pubmed: 6820061
    13. Palmer E, Driancourt MA. Some interactions of season of foaling, photoperiod and ovarian activity in the equine.. Livestock Prod. Sci. 1983;10:197–210.
      doi: 10.1016/0301-6226(83)90035-0google scholar: lookup
    14. Saastamoinen M, Ojala M. Influence of birth month on race track records in young trotters.. Proc. VI World Conf. Anim. Prod., Helsinki, Finland 1988, p. 495.
    15. Speroff L. Normal and abnormal menstruation.. In: Current obstetric and gynecologic diagnosis and treatment. 5th ed. Lange Medical Publications, Los Altos, California 1984, 158–159.
    16. Scraba ST, Ginther OJ. Effects of lighting programs on onset of the ovulatory season in mares.. Theriogenology 1985;24:667–679.
      doi: 10.1016/0093-691X(85)90165-7google scholar: lookup
    17. Wesson JA, Ginther OJ. Influence of season and age on reproductive activity in pony mares on the bases of slaughterhouse survey.. J. Animal Sci. 1981;52:119–129.
      doi: 10.2527/jas1981.521119xpubmed: 7195392google scholar: lookup

    Citations

    This article has been cited 3 times.
    1. Salazar-Ortiz J, Camous S, Briant C, Lardic L, Chesneau D, Guillaume D. Effects of nutritional cues on the duration of the winter anovulatory phase and on associated hormone levels in adult female Welsh pony horses (Equus caballus). Reprod Biol Endocrinol 2011 Sep 29;9:130.
      doi: 10.1186/1477-7827-9-130pubmed: 21958120google scholar: lookup
    2. Koskinen E, Huhtinen M, Katila T. Serum progesterone levels in mares in winter and during transitional periods. Acta Vet Scand 1996;37(4):409-14.
      doi: 10.1186/BF03548080pubmed: 9050273google scholar: lookup
    3. Koskinen E, Kurki E, Katila T. Onset of luteal activity in foaling and seasonally anoestrous mares treated with artificial light. Acta Vet Scand 1991;32(3):307-12.
      doi: 10.1186/BF03546959pubmed: 1814179google scholar: lookup
    Subscribe to our newsletter
    Join 99,357 horse owners like you who receive our email updates on horse health and nutrition.