FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Theriogenology / Luteal blood flow during the estrous cycle in mares.
Theriogenology2002; 57(8); 2043-2051; doi: 10.1016/s0093-691x(02)00705-7

Luteal blood flow during the estrous cycle in mares.

Abstract: Transrectal color Doppler ultrasound was used for the noninvasive investigation of luteal blood flow during the estrous cycle in six mares. Color was displayed in Power-Mode, in which the number of color pixels on the ultrasound image is related to the number of moving blood cells. Three pictures with a maximum number of color pixels of the corpus luteum (CL) during an examination period of about 20 min were selected and digitized on a laptop equipped with an external frame grabber card. The intra-class correlation coefficient for the number of color pixels was 0.90. In all estrous cycles similar patterns of changes in (C), in the cross-sectional area of sectional planes of the CL (A), and in plasma progesterone levels (P) occurred. Variance component estimates for the effect of the mare on (C), (A) and (P) were 14, 23 and 4%, for the influence of day of estrous cycle they were 41, 5 and 58% and for the effect of estrous cycle they were 7, 5 and 5%, respectively. There were high positive correlations between cyclic changes in (C) and (P) (r = 0.58; P < 0.0001). The increase in (C) between Days 0 and 5 (Day 0: ovulation) remained at high levels until Day 7 and then decreased until Day 15. There were relationships between (C) and (A) (r = 0.37; P < 0.0001) and between (A) and (P) (r = 0.24; P 0.05). The results show that transrectal color Doppler sonography is a useful, noninvasive method for examining luteal blood flow in mares, and that there are cyclic changes and individual differences in the vascularization of the CL. The possible influence of luteal perfusion on fertility in mares needs to be investigated in further studies.
Get Full Text
Publication Date: 2002-06-18 PubMed ID: 12066864DOI: 10.1016/s0093-691x(02)00705-7Google 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.

The study examined changes in blood flow to the corpus luteum (a temporary endocrine structure in female ovaries) in horses during the estrous cycle using a non-invasive ultrasound technique. It found cyclic changes and individual variations in the blood supply, which can potentially impact fertility.

Methodology

  • Researchers used non-invasive transrectal colour Doppler ultrasound to investigate luteal blood flow during the estrous cycle in six horses.
  • Power-Mode colour display was used, which correlates the number of colour pixels on the ultrasound image with the number of moving blood cells.
  • Three images of the corpus luteum (CL), showing the maximum number of colour pixels were selected and digitised over a 20-minute examination period.

Results and Findings

  • The correlation coefficient for the number of colour pixels was found to be 0.90, indicating a high degree of correlation.
  • In all estrous cycles, the researchers found similar patterns of changes in the colour pixel count (C), the cross-sectional area of the CL (A), and in plasma progesterone levels (P).
  • Varying influences on (C), (A) and (P) were estimated for factors such as the individual horse, day of the estrous cycle, and the estrous cycle itself. The most significant impact was seen from the day of the cycle on (P) levels (58%) and on (C) levels (41%).
  • There was a high positive correlation (r=0.58) between cyclic changes in (C) and (P). This suggests that as the blood flow to the CL increased (symbolised by a high (C) value), the progesterone level also elevated, reinforcing the vital role of blood flow in hormonal cycling.
  • Fluctuations in (C) levels were observed across specific days of the estrous cycle, peaking between days 0 and 5, remaining high until day 7, and then decreasing until day 15.
  • Although correlations were established between (C) and (A), and between (A) and (P), these were not as strong as the correlation between (C) and (P).
  • No significant relationships were observed between individual variations in (C), (A) and (P) within and between different horses.

Conclusion

  • The study found cyclic and individual variations in the vascularization of the CL. These findings potentially have implications for the fertility of the horses, highlighting a need for further exploration.
  • The method of transrectal color Doppler sonography was affirmed as a valuable, non-invasive procedure for monitoring luteal blood flow in horses.

Cite This Article

APA
Bollwein H, Mayer R, Weber F, Stolla R. (2002). Luteal blood flow during the estrous cycle in mares. Theriogenology, 57(8), 2043-2051. https://doi.org/10.1016/s0093-691x(02)00705-7

Publication

Theriogenology
ISSN: 0093-691X
NlmUniqueID: 0421510
Country: United States
Language: English
Volume: 57
Issue: 8
Pages: 2043-2051

Researcher Affiliations

Bollwein, H
  • Gynäkologische und Ambulatorische Tierklinik der Universität München, Germany. heinrich.bollwein@gyn.vetmed.uni-muenchen.de
Mayer, R
    Weber, F
      Stolla, R

        MeSH Terms

        • Animals
        • Corpus Luteum / blood supply
        • Estrous Cycle / physiology
        • Female
        • Horses / physiology
        • Ovulation
        • Progesterone / blood
        • Ultrasonography, Doppler, Color

        Citations

        This article has been cited 5 times.
        1. Freccero F, Mislei B, Bucci D, Dondi F, Mari G. Effects of Intra-Uterine Fluid Accumulation after Artificial Insemination on Luteal Function in Mares.. Animals (Basel) 2022 Dec 23;13(1).
          doi: 10.3390/ani13010067pubmed: 36611677google scholar: lookup
        2. Ortega-Ferrusola C, Gómez-Arrones V, Martín-Cano FE, Gil MC, Peña FJ, Gaitskell-Phillips G, Da Silva-Álvarez E. Advances in the ultrasound diagnosis in equine reproductive medicine: New approaches.. Reprod Domest Anim 2022 Oct;57 Suppl 5(Suppl 5):34-44.
          doi: 10.1111/rda.14192pubmed: 35748405google scholar: lookup
        3. Requena F, Campos MJAPM, Martínez Marín AL, Camacho R, Giráldez-Pérez RM, Agüera EI. Assessment of Age Effects on Ovarian Hemodynamics Using Doppler Ultrasound and Progesterone Concentrations in Cycling Spanish Purebred Mares.. Animals (Basel) 2021 Aug 8;11(8).
          doi: 10.3390/ani11082339pubmed: 34438797google scholar: lookup
        4. Alonso MA, Silva LA, Affonso FJ, Lemes KM, Celeghini ECC, Lançoni R, Carvalho HF, de Arruda RP. Effect of hCG application at different moments of the estrous cycle on corpus luteum and uterine vascularization and serum progesterone concentration in mares.. Anim Reprod 2019 Oct 24;16(2):317-327.
          doi: 10.21451/1984-3143-AR2018-0103pubmed: 33224293google scholar: lookup
        5. Galvão AM, Ferreira-Dias G, Skarzynski DJ. Cytokines and angiogenesis in the corpus luteum.. Mediators Inflamm 2013;2013:420186.
          doi: 10.1155/2013/420186pubmed: 23840095google scholar: lookup
        Subscribe to our newsletter
        Join 99,344 horse owners like you who receive our email updates on horse health and nutrition.