English
A swollen umbilicus in a foal is a common abnormality that may involve the external navel, deeper umbilical structures within the abdomen, or both. While some cases are relatively minor, others can indicate infection, persistent fetal structures, an umbilical hernia, or another condition requiring prompt veterinary evaluation.
Because several umbilical disorders can produce similar outward signs, the cause of swelling is not always clear from appearance alone. Some problems remain localized, while others can progress internally or contribute to more widespread illness before obvious signs develop.
Understanding how the umbilical structures normally close after birth, what can cause swelling, and which symptoms warrant concern can help owners recognize when a young foal needs attention. Keep reading to learn how a swollen umbilicus in foals is diagnosed, treated, managed, and monitored to reduce the risk of complications.
Swollen Umbilicus in Foals
A swollen umbilicus is an enlargement of the navel area in a newborn or young foal. The swelling may involve the external umbilical stump, the internal umbilical structures, or both. [1][2][3]
The umbilicus is the remnant of the umbilical cord that connected the developing foal to the placenta during pregnancy. After birth, the cord breaks, and the remaining stump gradually dries, shrinks, and disappears over the following weeks. [1][4]
Some enlargement of the umbilical area may be noticed shortly after birth and is considered normal. However, persistent swelling, increasing size, heat, pain, or discharge are causes for further investigation. [1][5]
A swollen umbilicus may indicate disease affecting the umbilical remnants and should not be ignored. [3][6]
Umbilical disorders are among the most common health problems affecting neonatal foals. [1][2]
Swelling can occur for several reasons, including: [1][7][8]
- Infection
- Failed closure of the umbilical structures
- Fluid accumulation
- Umbilical hernia
What's your top priority with your horse's health?
What's your top priority with your horse's health?
Umbilical Anatomy in Newborn Foals
The umbilicus contains several structures that connected the developing foal to the placenta during pregnancy. [1][4]
The umbilical cord contains one umbilical vein, two umbilical arteries, and a structure called the urachus. [1][4]
After birth, these structures are no longer needed and begin to close and shrink. [1][4] The umbilical arteries, umbilical vein, and urachus gradually become fibrous remnants within the abdomen, while the external stump dries and disappears. [1][2]
This process normally occurs without complications. However, if the umbilical structures fail to close properly or become infected, swelling and other abnormalities can develop. [1][2][3][4][8]
Since some umbilical structures extend deep into the abdomen, disease affecting the umbilicus may involve more than the visible portion of the navel. [3][6]
Associated Symptoms
The signs associated with a swollen umbilicus vary depending on the underlying cause and the structures involved. [2][3] Some foals show only localized changes at the navel, while others develop signs of more widespread illness. [5][6]
Possible symptoms that may occur alongside a swollen umbilicus include: [1][2][3][5][7][8]
- Visible swelling of the umbilical area
- Heat, pain, or tenderness around the umbilicus
- Moisture, discharge, or pus from the navel
- Persistent urine leakage from the umbilicus
- Thickening of the umbilical stump
- A soft bulge consistent with an umbilical hernia
- Fever
- Reduced nursing or decreased appetite
- Depression or lethargy
- Joint swelling or lameness
- Poor growth or failure to thrive
Since serious complications can develop even when external signs appear mild, any persistent or abnormal umbilical swelling should be evaluated promptly. [2][3]
Table 1. Signs of swollen umbilicus in foals and what they may mean
| Sign noticed | Possible concern | Recommended response |
|---|---|---|
| Visible swelling of the umbilical area |
|
|
| Heat, pain, or tenderness around the navel |
|
|
| Moisture, discharge, or pus from the umbilicus |
|
|
| Persistent urine leakage from the umbilicus |
|
|
| Thickened or enlarged umbilical stump |
|
|
| Soft bulge at the navel |
|
|
| Fever, depression, or lethargy |
|
|
| Reduced nursing or decreased appetite |
|
|
| Joint swelling or lameness |
|
|
| Poor growth or failure to thrive |
|
|
When to Call the Veterinarian
A swollen umbilicus in a foal should be taken seriously because external swelling may not show the full extent of the problem. [3][6] Veterinary evaluation helps determine whether the issue is limited to the external stump or involves deeper umbilical structures, infection, or an umbilical hernia. [2][3]
Call a veterinarian promptly if a foal has: [1][2][3][5][7][8]
- Persistent or enlarging swelling around the umbilicus
- Heat, pain, tenderness, moisture, discharge, or pus at the navel
- Urine leakage from the umbilicus
- A bulge that becomes firm, painful, or difficult to reduce
- Fever, lethargy, reduced nursing, or poor growth
- Joint swelling, stiffness, or lameness
A veterinarian may perform a physical examination, ultrasound, bloodwork, cultures, or urinalysis depending on the foal’s signs. [1][2][5][6][8] Early diagnosis is important because infection can progress quickly in young foals, and treatment decisions depend on which structures are involved. [5][6]
Foals with fever, weakness, reduced nursing, severe pain, or signs of systemic illness need urgent veterinary care. These signs may indicate that the problem has progressed beyond a localized umbilical abnormality. [2][3]
Risk Factors
Several factors can increase a foal’s risk of developing a swollen or infected umbilicus. A key risk factor is failure of passive transfer, which occurs when a foal does not absorb enough protective antibodies from colostrum after birth. [1][2][5]
Because the umbilicus is an open route into the body shortly after birth, bacteria can travel into the remaining umbilical structures and may spread to the bloodstream or internal organs if infection is not controlled.
The foaling environment also plays an important role. Dirty bedding, contaminated stalls, wet conditions, and poor hygiene during birth can expose the fresh umbilical stump to high numbers of bacteria. [1][5]
Foals that are premature, weak, ill, or slow to stand and nurse may also be at increased risk. These foals may have reduced colostrum intake, delayed immune protection, or prolonged contact with contaminated bedding. Foals with septicemia are especially vulnerable because infection may involve the umbilicus as part of a broader systemic illness. [1][2][4]
Anatomical or developmental problems can also contribute to swelling around the navel. Since several disorders can produce similar outward signs, further evaluation is often needed to determine the underlying cause of the swelling and whether medical or surgical treatment is required. [3][6][7][8]
Causes of Swollen Umbilicus in Foals
A swollen umbilicus can develop for several different reasons, ranging from relatively minor conditions to serious infections involving structures deep within the abdomen.
Since some disorders affect internal umbilical remnants that are not visible from the outside, the underlying cause cannot always be determined from the appearance of the swelling alone. [1][2][3][6]
Common causes of a swollen umbilicus in foals include: [1][2][3][5][6][7][8]
- Umbilical infection, also called omphalitis
- Infection of the internal umbilical remnants
- Patent urachus
- Umbilical abscesses
- Umbilical hernias
- Fluid accumulation within the umbilical structures
Umbilical Infection
Umbilical infection, or omphalitis, occurs when bacteria enter the umbilical stump after birth. In mild cases, infection may involve the external stump and surrounding tissues. In more serious cases, bacteria can travel into the deeper umbilical structures and may spread through the bloodstream. [1][2][5]
Affected foals may have swelling, heat, pain, discharge, or moisture around the umbilicus. Some foals also show signs of systemic illness, such as fever, depression, poor nursing, or joint swelling if infection spreads beyond the navel. [1][2][5]
Infection of Internal Umbilical Remnants
After birth, several umbilical structures remain inside the foal’s abdomen as they close down and regress. These include the umbilical vein, umbilical arteries, and urachus. If bacteria infect these internal remnants, the foal may develop swelling at the navel even when the outside of the stump does not appear severely abnormal. [1][3][6]
Internal umbilical infections can involve one structure or several structures at the same time. Because these infections are not always visible from the outside, veterinarians may use ultrasound to evaluate the size, appearance, and involvement of deeper umbilical remnants. [1][3][6]
Patent Urachus
The urachus is a fetal structure that connects the bladder to the umbilicus before birth. It normally closes soon after the foal is born. If it remains open, urine may leak from the navel, a condition known as patent urachus. [1][4][8]
A patent urachus may occur on its own or develop secondary to inflammation, infection, or increased pressure within the abdomen. Foals with this condition may have a wet umbilicus, urine dripping from the navel, irritation of the surrounding skin, or swelling around the umbilical stump. [1][4][8]
Umbilical Abscesses
An umbilical abscess can form when infection becomes walled off within the umbilical tissues or remnants. This may create a firm, painful swelling near the navel. Abscesses may involve external tissues or deeper structures within the abdomen. [1][5][6]
Because abscesses can persist despite surface-level improvement, veterinary evaluation is important. Some cases respond to medical treatment, while others require surgical removal of infected tissue. [5][6][7]
Umbilical Hernias
An umbilical hernia occurs when the body wall does not fully close at the umbilical ring, allowing tissue or abdominal contents to push outward beneath the skin. This can create a soft swelling at the navel that may become more noticeable when the foal stands, strains, or moves. [3][7]
Some small umbilical hernias may be uncomplicated, but larger hernias or hernias that become painful, firm, or non-reducible require prompt veterinary attention. These changes may indicate that tissue is trapped within the hernia, which can become serious. [3][7]
Fluid Accumulation
Swelling around the umbilicus may also result from fluid accumulation within or around the umbilical structures. This can occur with inflammation, infection, trauma, or delayed closure of fetal remnants. [1][3][8]
Because fluid-filled swellings can resemble other umbilical disorders, owners should not rely on appearance alone to determine the cause. A veterinarian can assess whether the swelling is associated with infection, urination from the navel, herniation, or deeper umbilical involvement. [1][3][6][8]
Table 2. Possible causes of swollen umbilicus in foals
| Cause | What happens | What owners may notice | Why it matters |
|---|---|---|---|
| Umbilical infection |
|
|
|
| Internal umbilical remnant infection |
|
|
|
| Patent urachus |
|
|
|
| Umbilical abscess |
|
|
|
| Umbilical hernia |
|
|
|
| Fluid accumulation |
|
|
|
Diagnosis
Due to the range of different conditions that cause umbilical swelling, diagnostic testing is often needed to determine the underlying problem and assess its extent. [2][3] Evaluation is particularly important because infections may involve internal umbilical structures even when external abnormalities appear mild. [5][6]
Ultrasound is one of the most important diagnostic tools for evaluating the internal umbilical remnants. [1][5][6] It allows the veterinarian to assess structures that cannot be fully evaluated by external appearance alone.
Other diagnostic tools may include: [1][2][5][6][8]
- Complete blood count (CBC)
- Serum biochemistry testing
- Bacterial culture and antimicrobial susceptibility testing
- Urinalysis
- Blood culture
Early diagnosis is important because prompt treatment can reduce the risk of complications and improve the likelihood of a successful outcome. [5][6]
Treatment & Management of Umbilical Disorders
Treatment depends on the underlying cause of the swelling, the structures involved, and whether infection has spread beyond the umbilicus. [2][3] Early treatment can prevent umbilical disease from progressing and leading to serious complications. [1][6]
Treatment and management options may include: [1][2][3][5][6][7][8]
- Antimicrobial therapy
- Anti-inflammatory medications
- Supportive care for sick or septic foals
- Management of patent urachus
- Surgical removal of infected umbilical remnants, called omphalectomy
- Surgical repair of umbilical hernias when indicated
Surgery is recommended when infection involves internal umbilical structures, when multiple remnants are affected, when abscesses are present, or when medical treatment is unsuccessful. Treatment should be guided by a veterinarian and based on the foal’s clinical signs, diagnostic findings, and overall health status. [5][6][7]
Potential Complications & Prognosis
Umbilical disease can range from a localized problem affecting the navel to a serious condition involving multiple body systems. [2][3] The risk of complications increases when infection extends beyond the external umbilical stump into the internal umbilical remnants. [5][6]
Potential complications include: [2][3][5][6][8]
- Septicemia, or bloodstream infection
- Septic arthritis and joint infections
- Osteomyelitis, or bone infection
- Pneumonia
- Peritonitis
- Infection of the umbilical vein extending toward the liver
- Uroperitoneum associated with urachal abnormalities
- Intra-abdominal adhesions
Prognosis
The prognosis for a foal with a swollen umbilicus depends on the underlying cause, the foal’s overall health, and how quickly treatment begins. Mild or uncomplicated conditions, such as a small umbilical hernia without signs of infection or pain, may have a good outcome with appropriate monitoring and veterinary guidance. [3][7]
The prognosis is more guarded when swelling is caused by umbilical infection, abscessation, septicemia, or infection of deeper umbilical structures. These cases can become serious if bacteria spread through the bloodstream or involve internal tissues. Early diagnosis, appropriate antimicrobial therapy, supportive care, and surgery when needed can improve the chance of recovery. [1][2][5][6]
Foals with systemic illness, failure of passive transfer, or delayed treatment may have a higher risk of complications. Any foal with umbilical swelling, discharge, fever, depression, poor nursing, colic, or signs of urination from the navel should be examined by a veterinarian promptly. [1][2][8]
Prevention
Not all umbilical disorders can be prevented, but appropriate management around the time of birth can help reduce the risk of infection and other complications. [1][2] Prevention focuses on maintaining a clean environment, supporting normal healing of the umbilical stump, and promoting a healthy immune response in the newborn foal. [1][4]
Measures that may help reduce the risk of umbilical disease include: [1][2][3][4][8]
- Providing a clean foaling environment
- Following appropriate umbilical care protocols after birth, including keeping the foal’s umbilical area clean and dry and using an antiseptic umbilical dip where recommended by a veterinarian
- Monitoring the umbilical stump during the first days of life
- Ensuring adequate transfer of maternal antibodies through colostrum
- Identifying and treating failure of passive transfer when it occurs
- Promptly investigating persistent moisture, discharge, swelling, or urine leakage from the umbilicus
- Monitoring young foals for signs of illness or infection
Failure of passive transfer, septicemia, and unhygienic conditions are recognized risk factors for umbilical infections. [2][5] Early recognition of abnormalities and timely veterinary evaluation can help prevent minor umbilical problems from progressing into more serious disease. [1][6] Owners can also use post-foaling benchmarks to help monitor normal early foal development and identify concerns sooner.
Frequently Asked Questions
Here are some frequently asked questions about a swollen umbilicus in foals:
A swollen umbilicus in a foal means the navel area is enlarged, thickened, or otherwise abnormal after birth. The swelling may involve the external umbilical stump, deeper umbilical structures inside the abdomen, or both. Some mild enlargement can occur shortly after birth, but swelling that persists, increases, feels hot or painful, or has discharge should be investigated.
A swollen umbilicus in a foal can be serious because some umbilical disorders involve internal structures or infection that may spread beyond the navel. Even mild external swelling can be associated with deeper infection that is not visible from the outside. Prompt veterinary evaluation is especially important if the foal is feverish, dull, nursing poorly, lame, or has joint swelling.
A foal's umbilicus may swell because of infection, incomplete closure of fetal umbilical structures, fluid accumulation, an umbilical abscess, a patent urachus, or an umbilical hernia. These conditions can look similar from the outside, so appearance alone may not identify the cause. Veterinary assessment helps determine whether the problem is localized or involves deeper structures inside the abdomen.
Some swelling around a newborn foal's umbilicus can be normal shortly after birth as the umbilical stump dries, shrinks, and heals. However, normal swelling should not continue to enlarge, become painful, feel hot, leak fluid, or produce discharge. Persistent or abnormal swelling should be treated as a warning sign rather than a routine part of healing.
Signs of an umbilical infection in foals can include swelling, heat, pain, thickening, moisture, discharge, pus, fever, depression, reduced nursing, poor growth, lameness, or swollen joints. Some foals may only show mild changes at the navel even when internal umbilical remnants are affected. Because infection can spread through the bloodstream or to other tissues, these signs warrant prompt veterinary attention.
Urine leaking from a foal's umbilicus usually suggests a patent urachus, which occurs when the connection between the bladder and umbilicus does not close properly after birth. The area may stay wet or leak urine from the navel. Persistent moisture or urine leakage can increase the risk of infection and should be evaluated by a veterinarian promptly.
A swollen umbilicus in foals is diagnosed by assessing the foal's overall health, examining the swelling, and using diagnostic tests when needed. Ultrasound is especially useful because it can evaluate internal umbilical remnants that cannot be seen from the outside. Other tests may include complete blood count, serum biochemistry testing, bacterial culture and antimicrobial susceptibility testing, urinalysis, or blood culture in selected cases.
Ultrasound is used for umbilical swelling in foals because some important umbilical structures extend inside the abdomen. External examination alone may miss infection, fluid accumulation, abscesses, or enlarged umbilical remnants. Ultrasound helps guide treatment decisions by showing which structures are involved and how extensive the problem is.
A swollen umbilicus in foals is treated according to the underlying cause, the structures involved, and whether the foal has signs of wider illness. Treatment may include antimicrobial therapy, anti-inflammatory medication, supportive care, management of a patent urachus, or surgery. Early treatment helps reduce the risk of complications, especially when infection involves internal umbilical remnants.
A foal may need surgery for umbilical disease when infection involves internal umbilical structures, multiple remnants are affected, abscesses are present, or medical treatment is not successful. Surgery may also be recommended for some umbilical hernias, especially if they are large, persistent, painful, or involve trapped tissue. The need for surgery depends on the diagnosis and the foal's overall condition.
An umbilical hernia can cause swelling in foals when tissue bulges through a weakness in the body wall at the navel. The swelling may feel soft and may be uncomplicated in some cases. Veterinary evaluation is important because large, painful, persistent, or complicated hernias may require surgical repair.
Complications from umbilical disease in foals can include bloodstream infection, joint infection, bone infection, pneumonia, peritonitis, infection extending toward the liver, urine leakage into the abdomen, or internal adhesions. The risk is higher when infection spreads from the external stump into internal umbilical remnants. Some complications can become life-threatening if they are not recognized and treated promptly.
Umbilical problems in foals cannot always be prevented, but good management around birth can reduce the risk. A clean foaling environment, appropriate umbilical care, monitoring during the first days of life, and adequate colostrum intake all support normal healing and immune protection. Persistent moisture, discharge, swelling, or urine leakage should be investigated early.
A foal with a swollen umbilicus should see a veterinarian if the swelling persists, increases, feels hot or painful, leaks urine, produces discharge, or is associated with fever, poor nursing, depression, lameness, or joint swelling. Veterinary attention is also warranted when the cause of swelling is unclear, because deeper umbilical disease may not be obvious externally. Early diagnosis and treatment can help prevent minor problems from becoming serious.
Summary
A swollen umbilicus in a foal is an enlargement of the navel area that may involve the external stump, internal umbilical structures, or both.
- Some mild swelling can be normal after birth, but persistent swelling, heat, pain, discharge, or urine leakage should be evaluated by a veterinarian
- Common causes include umbilical infection, infected internal remnants, patent urachus, abscesses, fluid accumulation, and umbilical hernias
- Signs may include navel swelling, tenderness, pus, urine leakage, fever, reduced nursing, lethargy, joint swelling, lameness, or poor growth
- Diagnosis may involve a physical exam, ultrasound, bloodwork, culture, urinalysis, or other testing to determine which structures are affected
- Early veterinary treatment helps reduce the risk of serious complications
References
- Smith. M. Management of Umbilical Disorders in the Foal. In Practice. 2006.
- Reed. S. M. et al. Equine Internal Medicine. 3rd ed. Saunders Elsevier. 2010.
- Bryant. J. E. and Gaughan. E. M. Abdominal Surgery in Neonatal Foals. Veterinary Clinics of North America: Equine Practice. 2005.
- McKinnon. A. O. Equine Reproduction. 2nd ed. Wiley-Blackwell. 2011.
- Rampacci. E. et al. Umbilical Infections in Foals: Microbiological Investigation and Management. Veterinary Record. 2017.
- Oreff. G. L. et al. Surgical Management and Long‐term Outcome of Umbilical Infection in 65 Foals (2010‐2015). Veterinary Surgery. 2017.
- Auer. J. A. et al. Equine Surgery. Fifth edition. Elsevier. 2019.
- Divers. T. J. and Perkins. G. Urinary and Hepatic Disorders in Neonatal Foals. Clinical Techniques in Equine Practice. 2003.
