Colic in horses

Colic is a symptom of abdominal pain most commonly arising from the gastrointestinal tract. Much less commonly colic symptoms can also result from pathology of other organs such as the bladder.

Recognising colic

A major problem for you as a horse owner is identifying the signs of colic. That is because signs can vary greatly between individuals and may also depend on the severity of the pain. However, among the more common signs are:

• turning the head toward the flank
• pawing
• kicking or biting at the abdomen
• stretching out as if to urinate without doing so
• repeatedly lying down and getting up
• rolling, especially violent rolling
• sitting in a dog-like position, or lying down either on the side or on the back
• lack of appetite
• putting head down to water or splashing in water without drinking
• change in nature of droppings
• change in normal gastrointestinal sounds
• bloating or distension of the abdomen
• sweating
• rapid respiration
• elevated heart rate
• change in mucus membrane colour and capillary refill time
• changes in demenour i.e. quiet and lethargic
• cool extremities

It is a good idea for you as an owner to learn how to take your horses heart rate, respiration rate and gastrointestinal sounds with a stethoscope.  If can become familiar with these signs when your horse is not unwell it may help to assess for changes associate with colic.

Taking immediate action

Time is one of the most critical factors if colic is to be successfully treated.  While a number of cases resolve without medical intervention, a significant percentage do require prompt medical care and a small percentage require emergency surgery. If you suspect your horse is suffering from colic, the following action plan is suggested:

1. Remove horses food
2. Notify your veterinarian immediately
3. Be prepared to provide the following specific information -
   • Behavioural signs, such as pawing, kicking, rolling, not eating, quiet or lethargic etc.
   • Digestive noises, or lack of them
   • Droppings, including colour, consistency and frequency
   • Any recent changes in management, feeding or exercise
   • Medical history, including deworming and any past episodes of abdominal pain
   • Breeding history and pregnancy status if the patient is a mare and recent breeding history if the patient is a stallion
   • Insurance status and value of the horse (NOTE: the insurance carrier should be notified as directed in the terms of the policy)
4. Keep the horse as calm and comfortable as possible
5. Allow the animal to lie down if it appears to be resting and is not at risk of injury
6. If the horse is rolling or behaving violently, attempt to walk the horse slowly.  Make sure you are safe and that the horse is in a safe environment if it does go down i.e. clear open grassy area
7. Do not administer drugs unless specifically directed to do so by your veterinarian. Drugs may camouflage problems and interfere with an accurate diagnosis and assessment of severity
8. Follow your veterinarian’s advice exactly and await their arrival

Diagnosing the cause

Your veterinarian will establish the severity of the colic and work on identify its cause. The examination and/or treatment may include the following procedures:

• observation of such signs as sweating, abdominal distension (bloating), rapid breathing, flared nostrils, and abnormal behaviour
• obtaining an accurate history
• monitoring vital signs including temperature, heart and respiration rate, colour of the mucous membranes and capillary refill time
• passage of a stomach tube to determine presence of excess gas, fluids and ingesta within the stomach
• rectal palpation for evidence of intestinal blockage, distension or other abnormalities
• blood test for white cell count and other data
• abdominal tap in order to evaluate protein level and cell type in the peritoneal fluid which is the fluid around the intestines
• faecal tests for sand content or parasite eggs
• analgesics or sedatives to relieve pain and distress
• laxatives and/or fluids to help re-establish normal intestinal function
• continued observation to determine response to treatment
• fluid therapy (either by stomach tube or intravenous)
• surgery
• When the colic is catastrophic, for example if rupture of the gastrointestinal tract has occurred, euthanasia is the optimal treatment to relieve pain and suffering and prevent an awful death.

Classifying colic

The exact steps your veterinarian will follow will depend on his or her findings. For example, some cases of colic can only be resolved through surgery. Even though there are a myriad causes, most cases of gastrointestinal colic fall into one of three groups:

1. Intestinal Dysfunction - This is the most common category and simply means that the horse’s bowels are not working properly. It includes such things as gas distension, impaction, spasms and paralysis
2. Intestinal Accidents - These occur less frequently and include displacements, torsions and hernias, whereby sections of the intestine become trapped or pinched in body cavities. Some horses seem anatomically predisposed to such problems. Intestinal accidents almost always require emergency surgery.
3. Enteritis or Ulcerations - These are colics related to inflammations, infections and ulcerations within the digestive tract.  Can be caused by numerous factors, including stress, disease, salmonellosis and parasites.

Prevention

While horses seem predisposed to colic due to the anatomy and function of their digestive tracts, management can play a key role in prevention. Although not every case is avoidable, the following guidelines can maximise the horse’s health and reduce the risk of colic:

• Establish a daily routine - including feeding and exercise schedules.
• Feed a high quality diet comprised primarily of roughage
• Avoid feeding excessive grain and energy dense concentrates or mixes feeds. Dilute these feeds with chaff if necessary.
• Divide daily concentrate rations into two or three smaller feedings rather than one larger one to avoid overloading the horse’s digestive tract. Hay is best fed free choice however show caution with large round bales as they can result in impaction colic.
• Set up a parasite control program with the help of your veterinarian. Utilise faecal egg counts at planned intervals to determine when to treat individuals and repeat faecal egg counts after treatment to monitor effectiveness and development of parasite resistance.
• Provide exercise and /or turnout on a daily basis, confinement to a stable 24/7 is not desirable for healthy gastrointestinal function
• Change the intensity/duration of an exercise regimen gradually
• Provide fresh, clean water at all times (the only exception is when the horse is excessively hot - then it should be given small sips of water until it has recovered).
• Avoid medications unless they are prescribed by your veterinarian, especially pain-relief drugs (analgesics) which can cause ulcers.
• Check hay, bedding, pasture, and environment for potentially toxic substances, such as mould, noxious weeds and other ingestible foreign matter.  For example lead ropes, bailing twine and hay nets if ingested can result in foreign body obstructions that require surgical removal.
• Avoid putting feed directly on the ground, especially in sandy soils.  Also avoid feeding from feeders made from old vehicle tyres that may contain wire.
• Make dietary and other management changes as gradually as possible. Change feed gradually over a period of 7 - 14 days.
• Reduce stress. Horses experiencing changes in environment or workloads are at high risk of intestinal dysfunction.
• Pay special attention to horses when transporting them or changing their surroundings such as at shows
• Observe foaling mares pre- and postpartum for any signs of colic. Also watch carefully any horses that have had a previous episode of colic. They may be at greater risk or recurrent colic.
• Maintain accurate records of management, feeding practices, and health.
• Maintain your horses dental care to ensure effective grinding of feed material and avoid pain within the mouth, which may reduce water intake during cold weather.

Summary

Virtually any horse is susceptible to colic. Age, sex and breed differences in susceptibility seem to be relatively minor. The type of colic seen appears to relate to geographic or regional differences, probably due to environmental factors such as sandy soil or climatic stress.

Importantly with conscientious care and management, we have the potential to reduce and control colic, however there are times when its occurrence is unfortunately purely bad luck.  Colic is unfortunately a significant cause of mortality in horses due to the anatomical configuration of the equine gastrointestinal tract and needs to be treated promptly by your veterinarian to ensure the best outcome.

This content was originally published by Equine Veterinarians Australia (EVA), a special interest group of The Australian Veterinary Association.