Colic, defined as abdominal pain in horses, is a condition that ranges from mild discomfort to severe, life-threatening situations. In foals, colic presents unique challenges and concerns, due to their physiology and development.

Colic in foals can be challenging to diagnose, as there are numerous potential causes that a veterinarian must assess. Veterinarians use a combination of physical examination, X-rays, ultrasound, and other diagnostic tests to identify the cause of colic, and to determine the possible treatment options.

Many causes of colic in foals have a good prognosis with early recognition and treatment. This article aims to provide a comprehensive overview of colic in foals, covering its causes, symptoms, diagnosis, treatment, and prevention strategies.

Colic in Foals

Colic is a complex and potentially serious condition characterized by abdominal pain and discomfort. It is not a disease in itself but rather a symptom or clinical sign of an underlying issue in the horse’s abdomen, usually involving the gastrointestinal system.

Colic in foals presents slightly different than in adults. Foals are less likely to show traditional symptoms such as kicking or biting at the abdomen, rolling excessively, or the Flehmen response.

The main symptoms of colic in foals include: [1][2]

  • Drooling and/or teeth grinding
  • Laying on their back for long periods, particularly after nursing
  • Dog-sitting
  • Lack of interest in nursing
  • Diarrhea
  • Reduced appetite
  • A distended abdomen
  • Straining or difficulty defecating
  • Elevated heart rate and respiratory rate

Causes of Colic in Foals

The causes of colic in foals can be multifaceted and sometimes differ from those in adult horses. Common causes include:

  • Digestive Tract Obstructions: These can be due to meconium impaction in newborns or other blockages in older foals.
  • Gastrointestinal Malformations: Congenital issues like atresia ani or intestinal torsions can lead to colic symptoms.
  • Infections: Gastrointestinal infections, such as clostridial enterocolitis or viral infections, can cause colic.
  • Ulcers: Gastric ulcers are relatively common in foals and can lead to colic.
  • Parasitic Infestations: As foals age, they become more exposed to parasites, which can cause gastrointestinal distress. Strongyloides larvae can be passed in the dam’s milk.
  • Dietary Issues: Improper feeding practices, including overfeeding, can disrupt a foal’s delicate digestive system.

The management of colic varies based on the underlying cause and the severity of the condition. In the following sections, we will delve deeper into some of the common causes of colic, and discuss risk factors, diagnosis and treatment.

Meconium Impaction

Meconium impaction is a frequent cause of colic in newborn foals, most commonly occurring in foals between 1 and 2 days old. [1][3] Meconium is the first feces of the foal, and consists primarily of intestinal secretions and cellular debris that accumulate while the foal is in utero. [1]

Normally, meconium passes within the first few hours after birth, and is black or dark green in colour, with a firm consistency. [1][2] If the foal does not pass the meconium normally, it can block the intestinal tract and prevent the flow of contents.

The accumulation of intestinal contents results in severe abdominal distention and pain for the foal. Some foals may posture as if they are urinating, as they strain to pass their meconium. [1]

Risk Factors

Male foals have a higher risk of meconium impaction compared to females. [2] The exact reason for this is unknown, but it may be related to the smaller pelvic size in males. [2]

Other risk factors for impaction colic in foals include: [4]

Diagnosis

Diagnosis of meconium impaction involves digital examination of the rectum. In this procedure the veterinarian gently inserts a gloved finger into the foal’s rectum to palpate for any hard masses of meconium.

If the meconium is not palpable, the veterinarian may need ultrasound or X-rays of the abdomen to identify the meconium mass.

Treatment

Treatment typically involves an enema of mild soap and water, to loosen the meconium and allow it to pass freely. [1] Commercially available enemas for humans are not recommended as they can result in phosphate toxicity in foals if used multiple times. [1]

If the foal does not respond to multiple enemas, more advanced treatment such as acetylcysteine enemas or surgical intervention may be necessary. [1][4][5]

Treating foals with enemas can be risky, as aggressive or repeated enema administration can cause irritation or injury to the rectum. [2] In severe cases, the rectum may rupture, releasing intestinal contents into the abdomen. [2]<