Study flags postpartum colic risk factors in Thoroughbred broodmares
Bottom line
A prospective UK and Ireland study is helping clarify which Thoroughbred broodmares are more likely to develop post-partum gastrointestinal colic. In an abstract published in Equine Veterinary Education from the 14th International Equine Colic Research Symposium, researchers from the University of Liverpool reported that colic risk was higher in mares with a previous history of colic, those given NSAIDs in the prior 28 days, those receiving calcium supplementation, and those spending more hours stabled each day. Risk was lower as more days passed after foaling, and in mares with current access to grass. The work builds on the same research group’s companion dataset showing 39 post-partum colic episodes across 33 mares on 29 UK and Irish stud farms during the 2021 and 2022 stud seasons, with about one-third of episodes occurring in the first 10 days after foaling. (beva.onlinelibrary.wiley.com)
Why it matters: For equine veterinarians and stud-farm teams, the findings reinforce that the immediate post-foaling window deserves especially close monitoring, particularly in mares with a known colic history or management factors that may limit turnout. The study doesn’t prove that NSAIDs, calcium supplementation, or stabling directly cause colic, but it does point to practical risk markers that could help shape surveillance, case triage, and conversations with pet parents and breeding clients about turnout, pain management, and early recognition. Postpartum mares are already recognized as being at elevated risk for large-colon and cecal disorders, so better risk stratification could support earlier intervention. (beva.onlinelibrary.wiley.com)
What to watch: The authors said multivariable analysis was still ongoing, so the next step is to see which factors remain independently associated with post-partum colic after adjustment. (beva.onlinelibrary.wiley.com)
Key facts
- Study type
- Prospective nested matched case-control study
- Population
- UK and Irish Thoroughbred broodmares
- Setting
- 29 UK and Irish stud farms
- Cases
- 39 post-partum colic episodes in 33 mares
- Higher-risk factors
- Previous colic history, NSAIDs in prior 28 days, calcium supplementation, and more hours stabled per day
- Lower-risk factors
- More days since foaling and current access to grass
- Early timing
- About one-third of episodes occurred within 10 days after foaling
- Analysis status
- Multivariable analysis was still ongoing
A new prospective study from UK and Irish Thoroughbred stud farms is adding detail to a long-recognized clinical problem: post-partum broodmares face meaningful colic risk, and some of that risk may be identifiable in advance. In research presented through Equine Veterinary Education in July 2024, investigators found that previous colic history, recent NSAID exposure, calcium supplementation, and more hours stabled per day were associated with increased odds of post-partum gastrointestinal colic, while access to grass and increasing days since foaling were linked to lower odds. (beva.onlinelibrary.wiley.com)
The findings come from the University of Liverpool group that has been studying post-partum colic in Thoroughbred broodmares across the 2021 and 2022 stud seasons. Their companion incidence-and-outcomes report enrolled 29 stud farms and followed 538 mares in 2021 and 746 in 2022, documenting 39 colic episodes in 33 mares. Most episodes involved the large colon, 41% were considered to need surgery, 64% warranted hospital admission, and overall survival was 82%. About one-third occurred within the first 10 days after foaling, underscoring how concentrated the risk can be in the early post-partum period. (beva.onlinelibrary.wiley.com)
In the risk-factor analysis, the authors used a prospective nested matched case-control design. Mares were eligible if they had foaled that season and still had a foal at foot, and each colic case was compared with three time-matched controls. Univariable analysis found higher colic odds in mares with crib-biting or windsucking behavior, a previous colic history, NSAID administration in the prior 28 days, moxidectin administration in the prior 28 days, calcium dietary supplementation, and increasing daily stabling time. Lower odds were associated with more days since foaling and current access to grass. The authors noted that multivariable analysis was still in progress, which is an important caveat when interpreting which factors may be independently predictive. (beva.onlinelibrary.wiley.com)
That caution matters because some of these signals may reflect management choices around mares already considered higher risk, rather than direct causal effects. For example, recent NSAID use could be a proxy for other post-foaling complications or pain, and calcium supplementation may track with particular farm protocols or reproductive management decisions. Even so, the stabling and grass-access findings fit with broader clinical concern that postpartum mares are vulnerable to large-colon displacement, torsion, impaction, and cecal disease, especially during a period of abrupt physiologic and management change. (beva.onlinelibrary.wiley.com)
Outside this specific study, the broader equine literature has consistently treated broodmares, and especially periparturient Thoroughbreds, as a distinctive colic population. Merck Animal Health’s equine health library notes that postpartum mares are especially at risk for large-colon and cecal disorders, while review articles on periparturient mares describe postpartum colic as a common diagnostic and management challenge in field and referral practice. Prior research has also suggested that some severe forms, such as large colon volvulus in Thoroughbred broodmares, may have population-level or even heritable patterns worth further investigation. (merck-animal-health-usa.com)
Why it matters: For veterinary professionals serving breeding operations, this study offers something more actionable than the general warning that “broodmares colic.” It suggests a shortlist of factors that may help identify mares needing tighter observation in the days and weeks after foaling: recent colic history, more confinement, recent medication exposures, and possibly specific supplementation practices. It also supports operational discussions with farm managers about turnout access, postpartum monitoring protocols, and how quickly mares with mild early signs should be examined or referred. Because the companion outcomes study found that a substantial share of cases required admission or surgery, even modest gains in early recognition could be clinically meaningful. (beva.onlinelibrary.wiley.com)
There’s also a research takeaway. This is prospective field data from commercial stud farms, which is valuable in a space where many recommendations still rely on retrospective case series or expert experience. But until the multivariable model is published in full, clinicians should treat these findings as hypothesis-sharpening rather than practice-changing proof. Associations seen on univariable screening can weaken after adjustment for confounding, and the abstract format leaves unanswered questions about effect modification, farm-level clustering, and how management variables interacted. (beva.onlinelibrary.wiley.com)
What to watch: The key next step is full publication of the adjusted analysis, along with any farm-level recommendations the Liverpool group derives from it. If the independent signals hold up, the work could inform postpartum risk checklists for broodmare practice, especially during the first few weeks after foaling when the burden appears highest. (beva.onlinelibrary.wiley.com)