Risk factors for post-partum colic in a population of broodmares

Risk factors for post-partum colic in a population of UK and Irish Thoroughbred broodmares
Equine Vet J. 2026 Jun 30. doi: 10.1002/evj.70219. Online ahead of print.
Authors
E Cullen 1 , H B Carslake 1 , I Henderson 2 , S Stoneham 1 , G L Pinchbeck 3 , D C Archer 1
Affiliations

1 Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst Campus, Neston, UK.
2 Ballylinch Stud, Thomastown, Kilkenny, Ireland.
3 Department of Livestock and One Health, University of Liverpool, Leahurst Campus, Neston, UK.

PMID: 42381284
DOI: 10.1002/evj.70219

Abstract

Background: Broodmares are at increased risk of gastrointestinal colic. However, colic risk factors specific to this population have not been investigated.

Objective: To investigate horse- and management-level risk factors for post-partum colic in a cohort of Thoroughbred broodmares in the United Kingdom and Ireland.

Study design: Prospective, nested case-control study.

Methods: Twenty-nine Thoroughbred stud farms in the United Kingdom and Ireland were recruited, and 1044 mares were followed over the 2021 and/or 2022 foaling seasons. Data were collected on signalment, medical and management history for post-partum colic mares and matched (3:1) controls. Multivariable analysis was conducted using conditional logistic regression.

Results: Due to strong collinearity between days post-partum and time spent stabled, two multivariable models were built. Days post-partum (Model 1: OR 0.9, 95% CI 0.8-0.9; p < 0.001) and increasing hours stabled (Model 2: OR 1.2, 95% CI 1.1-1.3; p < 0.001) were strongly associated with increased risk of post-partum colic. Colic risk was highest immediately post-partum, with reduction in likelihood of colic up to 50 days after foaling. NSAID use in the previous 28 days (Model 1: OR 6.2, 95% CI 2.0-65.5; Model 2: OR 4.1, 95% CI 1.1-15.0; p = 0.048) and a history of previous colic (Model 1: OR 7.4, 95% CI 1.2-7.9; Model 2: OR 5.3, 95% CI 1.7-17.1; p = 0.01) were also associated with increased colic risk. Calcium supplementation was associated with increased likelihood of post-partum colic in Model 1 only (OR 4.4, 95% CI 1.3-15.7; p = 0.04). Main limitations: Mares comprised a small sub-population of UK and Irish Thoroughbred broodmares. Pre-partum colic was not investigated. Conclusions: Maximising turnout in post-partum broodmares may reduce colic risk, immediately post-partum and up to 50 days. Broodmares who have recently received NSAIDs, have a history of colic or are receiving a calcium-based supplement may be at increased risk of post-partum colic. Keywords: foaling; gastrointestinal; horse; large colon; stud. © 2026 EVJ Ltd.