Investigations into fetal and neonatal losses in the horse.

The research article discusses the causes of pregnancy failure and neonatal loss in horses, and what impacts these losses have. Conducted over 10 breeding seasons between 1969 and 1979 at the Equine Research Station in Newmarket, England, the study provides insight into the influences, common causes, and measures to prevent such losses.

Fundamental Aim of Research

The study seeks to identify potential causes behind pregnancy failures or neonatal losses amongst horse populations. This information can then be used to:

• Control contagious diseases which might be contributing to these losses.
• Implement measures to prevent further losses in future pregnancies.

The research highlights the crucial role of pathologists in identifying infection agents, congenital defects, twinning, and potential signs of uterine pathology.

Importance of History Taking

The study emphasizes the importance of a comprehensive history of a mare prior to and during pregnancy. This should ideally include:

• The mare’s previous breeding history.
• The sire of the foal and the stud where he originates from.
• The date of the last covering.
• The mare’s movements since she was bred.
• The mare’s health during pregnancy, including any signs of impending abortion such as lactation, vaginal discharge, or colic.
• Events at parturition, and the postnatal period.

Losses in Early Gestation

The research found that only 4.4% of the abortion and neonatal material presented for examination over the 10 breeding seasons was less than 120 days gestational age. Despite most of this early material being autolyzed or decomposing when aborted, the presence of deformities, twinning, and some placental lesions could still be recognized. This underlines the point that many early abortions in horses often go unseen, an issue clinicians are familiar with.

Implications and Conclusions

Information detailed in this study can be used to prevent financial losses for brood mare owners, given the high associated costs. The research also discusses the infertility of mares and how factors such as the breeding history of the mare, its age, and specific sire characteristics can impact pregnancy outcomes. Also noted is a higher abortion rate in mares that were artificially inseminated.