Normal regression of the internal umbilical remnant structures in Standardbred foals.
Abstract: Diseases affecting the internal umbilical remnant are common in foals. Ultrasound is used to diagnose abnormalities of these structures, and to monitor treatment. However, little is known about the progression of normal internal umbilical remnant regression. Objective: To document normal regression of the umbilical remnant in foals over the first 6 weeks of life. Methods: Prospective, longitudinal cohort study. Methods: Weekly ultrasound examinations were performed beginning at 1 day of age in 34 healthy Standardbred foals. The umbilical vein was measured in cross section just cranial to the external umbilicus, at the level of the liver and midway between these points. The umbilical arteries were measured in cross section just caudal to the external umbilicus, at the apex of the bladder and at the midpoint of the bladder. The urachus was imaged longitudinally as it exited the bladder. Reduction in size over time was evaluated as percentage change in diameter. Results: Structure diameter decreased linearly over time. The largest measurements were at 24 hours of age with a median umbilical vein diameter of 0.83 cm (IQR 0.77-1.02 cm), median umbilical artery diameter of 0.61 cm (IQR 0.56-0.70 cm) and median urachal diameter of 1.07 cm (IQR 1.02-1.14 cm). There was a significant reduction in diameter for all structures (16.0%-21.9%; corrected P < .001) within the first week of life. Conclusions: All foals were of a single breed, and examinations and measurements were performed by multiple individuals. Conclusions: The internal umbilical remnants (umbilical vein/arteries, and urachus) rapidly regress over the first few weeks of life. The median internal umbilical remnant diameters reported here are smaller than previously reported values, emphasising the importance of accounting for age when diagnosing umbilical abnormalities. In a healthy Standardbred foal, normal structures are difficult to definitively identify via transcutaneous ultrasound by 5-6 weeks of age.
© 2020 EVJ Ltd.
Publication Date: 2020-04-30 PubMed ID: 32289179DOI: 10.1111/evj.13267Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This study investigates the natural regression of the internal umbilical remnant in Standardbred foals over the first six weeks of life. The findings reveal a rapid regression in umbilical remnants (umbilical vein/arteries, and urachus) during this period, emphasizing the need to consider the foal’s age when diagnosing umbilical abnormalities.
Study Details
- The focus of the research was on internal umbilical remnant diseases that are common in foals.
- were identified and measured weekly from the first day of birth until six weeks of age.
- The research was performed as a prospective, longitudinal cohort study involving 34 healthy Standardbred foals.
- Diagnostic ultrasound was the tool used to detect and monitor any abnormalities within these structures.
Methodology
- The researchers performed weekly ultrasound examinations.
- The umbilical vein was measured in three areas: just cranial to the external umbilicus, at the level of the liver, and midway between.
- The umbilical arteries were also measured in three areas: just caudal to the external umbilicus, at the apex of the bladder, and at the midpoint of the bladder.
- The urachus was imaged longitudinally as it exited the bladder.
- The reduction in size over time was evaluated based on the percentage change in diameter.
Results
- There was noted to be a linear decrease in structure diameter over time. The largest measurements were recorded at 24 hours of age.
- Within the first week of life, all structures showed a significant reduction in diameter ranging from 16.0% to 21.9%.
- These findings are smaller than previous reported values for these structures, indicating a possible overlooked factor of age in prior diagnoses and studies.
Conclusions
- All foals included in the study were of a single breed and examinations were conducted by multiple individuals, which adds a level of variability in data collection.
- By 5-6 weeks of age, it was challenging to definitively identify the normal structures of a healthy Standardbred foal via transcutaneous ultrasound.
- This rapid regression of the internal umbilical remnants process emphasizes the significance of age consideration when diagnosing umbilical abnormalities.
Cite This Article
APA
McCoy AM, Lopp CT, Kooy S, Migliorisi AC, Austin SM, Wilkins PA.
(2020).
Normal regression of the internal umbilical remnant structures in Standardbred foals.
Equine Vet J, 52(6), 876-883.
https://doi.org/10.1111/evj.13267 Publication
Researcher Affiliations
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
MeSH Terms
- Animals
- Horses
- Longitudinal Studies
- Prospective Studies
- Umbilical Veins
- Umbilicus / diagnostic imaging
- Urachus
Grant Funding
- University of Illinois Companion Animal Research Funds
References
This article includes 12 references
- Linford RL. Disorders of the bladder, urachus, and umbilicus in the neonatal foal.. In: Western Veterinary Conference, Las Vegas, NV. 2011.
- Reef VB, Collatos C. Ultrasonography of umbilical structures in clinically normal foals.. Am J Vet Res 1988;49:2143-6.
- Franklin RP, Ferrell EA. How to perform umbilical sonograms in the neonate.. Proc Am Assoc Equine Practr 2002;48:261-5.
- Reef VB. Equine pediatric ultrasonography.. Compend Contin Educ Pract 1991;12:1227-85.
- Reimer JM. Ultrasonography of umbilical remnant infections in foals.. Proc Am Assoc Equine Practr 1993;39:247-8.
- Reef VB. Abnormalities of the neonatal umbilicus detected by ultrasound.. Proc Am Assoc Equine Practr 1986;32:157-62.
- Morresey PR. Umbilical problems.. Proc Am Assoc Equine Practr 2014;60:18-21.
- Reef VB, Collatos C, Spencer PA, Orsini JA, Sepesy LM. Clinical, ultrasonographic, and surgical findings in foals with umbilical remnant infections.. J Am Vet Med Assoc 1989;195:69-72.
- Kay M, Wobbrock J. ARTool: Aligned Rank Transform for Nonparametric Factorial ANOVAs.. 2019.
- Wobbrock JF, Findlater L, Gergle D, Higgins J. The aligned rank trasnform for nonparametric factorial analyses using only ANOVA procedures.. In: ACM Conference on Human Factors in Computing Systems. Chicago, IL. 2011; p. 143-6.
- R Core Team. R: a language and environment for statistical computing.. Vienna, Austria: R Foundation for Statistical Computing; 2018.
- Holm S. A simple sequentially rejective multiple test procedure.. Scand J Stat 1979;6:65-70.
Citations
This article has been cited 4 times.- Vitale V, Nocera I, Sgorbini M, Aliboni B, Laus F, Mannini A, Bazzano M. Ultrasonography Evaluation of Umbilical Structures in Clinically Healthy Donkey Foals during the First Week of Life. Animals (Basel) 2021 Jun 2;11(6).
- Hardefeldt L, Thomas K, Page S, Norris J, Browning G, El Hage C, Stewart A, Gilkerson J, Muscatello G, Verwilghen D, van Galen G, Bauquier J, Cuming R, Reynolds B, Whittaker C, Wilkes E, Clulow J, Burden C, Begg L. Antimicrobial prescribing guidelines for horses in Australia. Aust Vet J 2025 Dec;103(12):781-889.
- Saitua A, Sanchez de Medina A, Bulnes F, Buzon A, Miraz R, Argüelles D, Diez de Castro E. Urogenital surgery in foals. Front Vet Sci 2025;12:1520491.
- Buzon-Cuevas A, Duaso J, Sanchez de Medina A, Sierra JM, Perez-Ecija A, Mendoza FJ. Description of a Modified Two-Step Omphalectomy Technique Using the LigaSure(™) Device to Remove the Whole Extrahepatic Umbilical Vein: A Case Series Study in Equine and Donkey Foals. Animals (Basel) 2025 Mar 28;15(7).
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists