Study flags postpartum colic risk factors in Thoroughbred broodmares

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A newly published study in Equine Veterinary Journal adds detail to a familiar clinical concern in broodmare practice: post-partum colic risk is not evenly distributed, and some of the strongest signals may be tied to how mares are managed in the days and weeks after foaling. Researchers led by E. Cullen examined Thoroughbred broodmares in the UK and Ireland and found that risk was highest immediately post-partum, then fell progressively through the first 50 days after foaling. (madbarn.com)

That matters because broodmares have long been recognized as a higher-risk group for gastrointestinal colic, but the specific drivers in the post-foaling period have been less clear. The new paper builds on earlier work from the same Liverpool-linked group, which reported incidence, diagnoses, and outcomes for post-partum gastrointestinal colic in UK and Irish Thoroughbred broodmares, including cases that required hospital referral and surgery. More broadly, the post-foaling mare presents a diagnostic challenge because abdominal pain can reflect gastrointestinal disease, reproductive tract injury, or other foaling-related complications. (beva.onlinelibrary.wiley.com)

In the new study, investigators followed 1,044 mares on 29 Thoroughbred stud farms during the 2021 and/or 2022 foaling seasons. Using a prospective nested case-control design with three matched controls per case, they evaluated both horse-level and management-level variables. Because days post-partum and time spent stabled were strongly correlated, the authors built two separate multivariable models. In those models, increasing days since foaling was associated with lower colic risk, while increasing hours stabled was associated with higher risk. Recent NSAID use and a previous history of colic were also linked with increased odds of post-partum colic, and calcium supplementation was associated with increased risk in one model only. (madbarn.com)

The practical message emerging from the paper is straightforward, even if causality isn't settled: postpartum turnout may be protective. The authors conclude that maximizing turnout in post-partum broodmares may help reduce risk, particularly in the immediate post-foaling period and up to 50 days afterward. At the same time, the NSAID and calcium findings should be interpreted carefully. This was an observational study, so those factors may reflect underlying clinical issues or management choices rather than direct causal effects. (madbarn.com)

Outside commentary specific to this paper appears limited so far, but the findings fit with the broader equine literature on post-parturient mares. Prior reports have described postpartum colic as a condition that can range from medically manageable impactions or ileus to surgical emergencies, and review articles emphasize that mares with persistent abdominal pain after foaling need thorough evaluation to rule out both intestinal and reproductive causes. The study also cites earlier evidence linking low ionized calcium concentrations with postpartum colic, which may help explain why supplementation stood out as a signal worth watching, even though it was not consistent across both models. (doi.org)

Why it matters: For veterinary professionals serving breeding farms, this study offers something more actionable than a general warning that broodmares are at risk. It suggests the first several weeks after foaling, especially the earliest days, deserve intensified attention, and it gives clinicians and farm teams a short list of mares that may merit closer monitoring: those spending longer periods stabled, those recently treated with NSAIDs, and those with a prior colic history. For practices advising stud farms, the work may also support conversations about turnout protocols, post-foaling observation plans, and how supplementation and analgesic use are documented and reviewed. (madbarn.com)

There are still important limits. The study focused on UK and Irish Thoroughbred broodmares, so the findings may not translate directly to other breeds, regions, or management systems. And because the stabling and postpartum-timing variables were collinear, the models can't fully disentangle whether confinement itself is driving risk, or whether it is acting as a marker for mares managed differently in the earliest, highest-risk window after foaling. (madbarn.com)

What to watch: The next step is whether these findings are replicated in other broodmare populations, and whether farms begin formalizing post-foaling turnout and risk-stratification protocols based on this early evidence. Related work from the same research stream on incidence, diagnoses, and outcomes could help translate these epidemiologic findings into more concrete prevention and triage guidance. (beva.onlinelibrary.wiley.com)