Plasma activin A concentrations during late gestation in Thoroughbred mares with abnormal pregnancies.
Authors: Tsogtgerel Munkhtuul, Murase Harutaka, Moriyama Hidekazu, Sato Fumio, Nambo Yasuo
Journal: Journal of equine veterinary science
Summary
# Editorial Summary: Activin A as an Early Marker for Abnormal Equine Pregnancies Late-gestational fetal loss remains a significant economic and welfare concern in the horse-breeding industry, yet reliable early diagnostic markers remain limited. Researchers compared plasma activin A concentrations in 40 healthy Thoroughbred mares against 30 mares experiencing pregnancy complications (fetal loss, red bag delivery, premature udder development, or vaginal discharge) during late gestation, building on previous findings that activin A rises progressively in normal pregnancies. Mares with abnormal pregnancies demonstrated significantly elevated activin A concentrations (≥138.2 pg/mL) compared to healthy controls, with 74.4% sensitivity and 77.5% specificity—a diagnostic accuracy that could meaningfully improve early identification of at-risk pregnancies. Notably, timing matters: whilst mares showing clinical symptoms or delivering abnormally had elevated activin A well before parturition, concentrations became indistinguishable between normal and abnormal deliveries within the final ten days of pregnancy, limiting its utility as a late-stage predictor. For practitioners, this research suggests that plasma activin A testing during early-to-mid late gestation could serve as a valuable screening tool to flag mares requiring closer monitoring, allowing earlier intervention strategies, though a negative result near term does not exclude delivery complications.
Read the full abstract on PubMed
Practical Takeaways
- •A plasma activin A concentration ≥138.2 pg/mL during late gestation warrants investigation for potential pregnancy complications and may enable earlier intervention to prevent abortion or dystocia
- •Activin A testing could help identify at-risk mares early enough to implement management changes or therapeutic interventions, reducing costly losses from late-term fetal loss
- •This biomarker may be most useful in mid-to-late gestation before the final 10 days, after which other clinical indicators become more apparent
Key Findings
- •Plasma activin A concentrations were significantly higher in abnormal pregnancies (≥138.2 pg/mL cutoff) compared to healthy pregnancies with 74.4% sensitivity and 77.5% specificity (P<0.001)
- •Abnormal pregnancies showed earlier elevation in plasma activin A concentration during late gestation compared to healthy gestational-age-matched controls
- •Plasma activin A was elevated in symptom and abnormal delivery subgroups but not distinguishable between normal and abnormal delivery within 10 days before parturition
- •This is the first study demonstrating significantly earlier increase in plasma activin A as a potential biomarker for abnormal pregnancies in Thoroughbred mares