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Tierarztliche Praxis. Ausgabe G, Grosstiere/Nutztiere2018; 46(1); 35-42; doi: 10.15653/TPG-170517

[Causes of abortion in horses – overview of the literature and own evaluations].

Abstract: The aim of this study was to summarize the current status of the possible causes, clinical symptoms and pathogenesis of abortion in the mare and to evaluate the frequency of varying causes of abortion in German thoroughbred breeding. An analysis of the literature using electronic libraries, journals and textbooks was performed. In addition, the results of examinations of 123 abortions of thoroughbred breeding in central Germany were evaluated. In the literature, bacterial infections are the most frequently described cause of abortion. Other important causes are infections with equine herpesvirus (EHV)-1 or -4, twin pregnancy and umbilical cord anomalies. Examples of rare causes of abortion are equine viral arteritis (EVA), equine infectious anemia, fungal or parasitic infections, fetal malformations and diseases of the mare. In our study of 123 abortions, no cause was found in 47.2 % of the analyzed abortions. Infections were responsible for 26.8 % of the abortions. The main pathogens were bacteria in 17.1 % of the cases followed by viruses (EHV-1/4) in 8.9 % of the cases. Fungal infection was diagnosed in 0.8 % of the cases. The most common cause of a non-infectious abortion was twin pregnancy (21.1%). Other causes of non-infectious abortion were fetal malformations (3.3 %), umbilical cord strangulations (0.8 %) and uterine torsion (0.8 %). The results of our own study suggest that in the future greater attention should be paid to ultrasonographic examinations in the early pregnancy to reduce the rate of abortions because of a twin pregnancy. To increase the detection rate of unknown causes of abortion, rarer causes of abortion should be investigated, including for EVA and chlamydia, as a matter of routine.
Publication Date: 2018-02-21 PubMed ID: 29536469DOI: 10.15653/TPG-170517Google Scholar: Lookup
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Summary

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This study seeks to elucidate the most common causes of abortions in horses, particularly German thoroughbreds, by reviewing literature and analyzing 123 abortion cases. The researchers found that bacterial infections and twin pregnancies are frequently attributable to abortions, and they suggested more thorough ultrasonographic examinations during early pregnancy to detect and prevent potential problems.

Literature Analysis and Case Evaluations

To better understand the causes of abortion in horses, researchers sourced information from electronic libraries, various journals and textbooks. Additionally, they scrutinized 123 cases of abortion in German thoroughbred horses.

  • Bacterial infections were found to be the most commonly mentioned cause in the literature. Other noteworthy causes include equine herpesvirus (EHV) infections, twin pregnancies and umbilical cord irregularities. Equine viral arteritis, equine infectious anemia, fungal or parasitic infections, fetal anomalies, and maternal health issues are cited as less common causes.
  • Out of the 123 examined cases of abortion, the cause remained unidentified in 47.2% of them. Among cases where a reason could be pinpointed, infections were the leading cause, accounting for 26.8% of these abortions.

Infections: Bacterial, Viral, and Fungal

  • Bacteria was the chief infectious pathogen, contributing to abortions in 17.1% of the cases.
  • Viruses (specifically EHV-1/4) accounted for 8.9% of the infections resulting in abortions.
  • Fungal infections were rarely a cause, representing only 0.8% of the examined cases.

Non-Infectious Causes

Non-infectious reasons also led to horse abortions:

  • Twin pregnancies were the most frequent non-infectious cause, representing 21.1% of the abortion cases.
  • Fetal malformations, umbilical cord strangulations, and uterine torsions were infrequent non-infectious causes, accounting for 3.3%, 0.8%, and 0.8% respectively.

Recommendations and Future Implications

The researchers suggested more diligent use of ultrasonographic examinations during early pregnancy to identify multiple pregnancies, fetal anomalies, or other potential causes of abortion. They also stressed on the need to consider even the less common causes of abortion, including equine viral arteritis and chlamydia, for a more comprehensive understanding and prevention strategy.

Cite This Article

APA
Weber R, Hospes R, Wehrend A. (2018). [Causes of abortion in horses – overview of the literature and own evaluations]. Tierarztl Prax Ausg G Grosstiere Nutztiere, 46(1), 35-42. https://doi.org/10.15653/TPG-170517

Publication

ISSN: 2567-5834
NlmUniqueID: 9715779
Country: Germany
Language: ger
Volume: 46
Issue: 1
Pages: 35-42

Researcher Affiliations

Weber, Ramona
    Hospes, Rainer
      Wehrend, Axel

        MeSH Terms

        • Abortion, Veterinary / epidemiology
        • Animals
        • Bacterial Infections / epidemiology
        • Bacterial Infections / veterinary
        • Breeding
        • Female
        • Germany / epidemiology
        • Horse Diseases / epidemiology
        • Horses
        • Pregnancy

        Conflict of Interest Statement

        Die Autoren bestätigen, dass kein Interessenkonflikt besteht.

        Citations

        This article has been cited 12 times.
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