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Home / Equine Research Bank / Equine Vet J / Twin management in the mare: A review.
Equine veterinary journal2024; 56(4); 650-659; doi: 10.1111/evj.14094

Twin management in the mare: A review.

Abstract: Twin gestation in the mare is undesirable and can have disastrous consequences. As in many cases, the key to success in twin management lies in a thorough follow-up and accurate recording of clinical findings in the pre-breeding examination. A pregnancy diagnosis in the mobility phase is imperative for a good outcome in the event of twin reduction. If a twin gestation is not diagnosed during this early pregnancy stage, several other procedures exist for managing post-fixation twins (>16 days) with varying degrees of success. Most twin pregnancies are the result of multiple ovulations (dizygotic twins). However, monozygotic twins are also sporadically diagnosed, due to the increasing number of transferred in vitro produced equine embryos. In these cases, the most optimal treatment strategy still needs to be determined. This review provides an overview of the various twin reduction techniques described with the expected prognosis as well as of some less reported techniques with their results. In addition, physiological events and the reduction techniques are demonstrated to the user in virtual 3-dimensional illustrations.
© 2024 EVJ Ltd.
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Publication Date: 2024-04-09 PubMed ID: 38594910DOI: 10.1111/evj.14094Google Scholar: Lookup
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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 paper reviews the methods and techniques used to manage twin pregnancies in horses, detailing strategies for early diagnosis, twin reduction and treatment. It also discusses differing outcomes depending on the type of twin pregnancy and how advancements in embryo transfer have impacted the occurrence of identical twins in horses.

Understanding Twin Pregnancies in Horses

  • The paper first explains that twin pregnancies are problematic in horses and can lead to undesirable outcomes. The survival and wellbeing of both the mare and her foals can be compromised due to the physical stress and complications that dual pregnancies can cause.
  • The research details that most twin pregnancies result from dual ovulation, leading to fraternal twins. However, anecdotal evidence suggests a rise in identical twins due to the increased practice of in-vitro embryo transfer. Different management approaches are required for both circumstances.

Pregnancy Diagnosis and Early Management

  • Early diagnosis of a twin pregnancy improves the chance for successful management. The researchers stress the necessary follow-up and recording of signs during the pre-breeding examination.
  • Diagnosis during the mobility phase is highlighted as crucial. The mobility phase is the period when the conceptuses are still moving freely in the uterus; twins can be separated more easily and the less viable one can be reduced without damaging the healthier one.

Management of Late Detection

  • The paper elaborates on various procedures that exist if twin gestation is not diagnosed during the early stage. The post-fixation stage is when the embryos have attached to the uterus walls and are no longer moving freely, making their separation more difficult.

Twin Reduction Techniques and Prognosis

  • The researchers review various techniques for twin reduction, including some that are under-reported. The expected outcomes and prognoses of these methods are provided, giving horse breeders and veterinarians a broad and comprehensive resource on this topic.
  • The study also uses 3-dimensional virtual illustrations to effectively demonstrate the physiological processes and reduction techniques. This visual aid makes it easier for readers to understand the complex procedures involved.

Cite This Article

APA
Peere S, van Den Branden E, Papas M, Gerits I, Smits K, Govaere J. (2024). Twin management in the mare: A review. Equine Vet J, 56(4), 650-659. https://doi.org/10.1111/evj.14094

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 56
Issue: 4
Pages: 650-659

Researcher Affiliations

Peere, Sofie
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.
van Den Branden, Emma
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.
Papas, Marion
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.
Gerits, Ilse
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.
Smits, Katrien
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.
Govaere, Jan
  • Department of Internal Medicine, Reproduction and Population Medicine, Ghent University, Merelbeke, Belgium.

MeSH Terms

  • Animals
  • Female
  • Pregnancy
  • Horse Diseases / therapy
  • Horse Diseases / diagnosis
  • Horses
  • Pregnancy Reduction, Multifetal / veterinary
  • Pregnancy, Twin
  • Pregnancy, Animal

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