Different Types of Colic and Their Causes
Colic = any kind of abdominal pain.
This can be caused by many different things. The main causes, and how they generally present, are described below.
(Not all horses read the rule book and some present differently to how we’d expect, but this is what we usually see).
More common:
Spasmodic colic
- Severe pain signs e.g rolling, lying down, getting up and down a lot
- High heart rate and respiratory rate
- Very noisy gut sounds in all 4 gut quadrants
- No abnormalities found on rectal
- May be dehydrated depending on how long colic has been going on for
- Responds well to medication
Intestinal impaction
- Pain signs present but often not as severe as some other colics – may be dull +/- lying down.
- Heart rate often not very high
- Quiet gut sounds in 1 or more quadrants
- Doughy impaction found on rectal (unless too far forward for vet to feel)
- Often dehydrated
- Can respond quite well to medication and oral fluid therapy
Gas (Tympanic) colic
- Severe pain signs
- High heart rate and respiratory rate
- Gut sounds are tympanic/tinkly in 1 or more quadrants
- Gas in gut often palpated on rectal
- Can respond well to medication
- Often respond well to exercise to encourage gas passing
Left dorsal displacement (nephrosplenic entrapment)
- Caused when colon becomes trapped in the space between the spleen and the left kidney
- Moderate consistent pain or intermittent painful episodes over a prolonged period
- Diagnosed on rectal palpation and/or abdominal ultrasound
- Rarely responds to medication alone
- May respond to fluids, starving and lunging
- May require surgery if medical management is unsuccessful
Right dorsal displacement
- Caused when colon migrates to sit between the caecum and the right body wall
- Mild, moderate or severe pain signs depending on severity, can deteriorate as blood supply to gut is compromised
- Diagnosed on rectal and/or abdominal ultrasound
- Horse may have gastric reflux
- Gum colour may be altered if gut blood supply compromised
- If mild signs, may be able to be treated medically but if severe pain, surgery is likely to be required.
Larval Cyathostominosis
- Caused when a large number of encysted small red worm larvae emerge from cysts in intestinal walls
- Colic of variable severity individual to horse
- Sudden onset of profuse, watery diarrhoea, dehydration, often show weight loss.
- May have an increased temperature, may show oedema in limbs and under belly, may have compromised circulation, seen by abnormal gum colour.
- Mild cases may be managed medically at home; severe cases should be referred to be medically managed in a hospital environment.
Peritonitis
- This is inflammation (can be due to infection) of the peritoneum (the membrane that the intestinal organs sit within)
- Often the cause of the inflammation or infection is unclear.
- Generally presents as colic, pyrexia, dullness and depression
- Can be diagnosed on peritoneal tap (taking a sample from the peritoneum by inserting a needle through the ventral abdominal wall under sedation and local anaesthetic.
Less common colic types:
Caecal impaction
Gastric impaction
Ascarid impaction
Sand colic
Intestinal strangulation
Intestinal torsion (twisted intestine or intussusception)
Enteritis
Colitis
Gastric ulcers (common in horses but don’t always cause colic)
Most of the above conditions, if they require referral, will not require surgery and respond well to medical management in a hospital. However, requiring surgery is a possibility depending on severity and progression.
Other conditions may be confused for colic.
This is why it is important for the vet to do a thorough physical examination of your horse and to take a full history.
- Flystrike (maggots) in sheath
- Laminitis or foot abscess other pain causing horse to want to lie down a lot/unwilling to get up
- Viral or bacterial infection causing horse to present as dull and inappetent
- Mouth/tooth pain causing inappetence
- Myopathies
Generally, if a horse colics once and recovers uneventfully, we often don’t investigate further.
However, if a horse colics multiple times in quick succession, we may recommend further diagnostics.
These include:
Gastroscopy, blood examination, abdominal ultrasound, testing for internal parasites (worms).