Equine Emergencies

The following 9 equine emergencies are described in terms of observable signs, the degree of urgency, and first-aid steps that should or, depending on the nature of the emergency, should not be taken prior to seeking immediate veterinary attention.

Choke: While many cases of choke will clear up spontaneously, or resolve within half an hour, some do not, as such, it should be treated as an emergency. Signs of choke include stretching out the neck, excess salivation, food material coming out of the nose, clenching of neck muscles. Horses that have experienced choke are susceptible to aspiration pneumonia and a range of other, although less likely, potentially life-threatening complications including esophageal rupture and kidney failure. Prior to calling the vet, try to ascertain what is causing the choke, food, bedding, another foreign body. Most importantly, move the horse to a quiet space and encourage it to relax with its head lowered to prevent any more saliva or food from entering the trachea or lungs. Do not allow the horse to eat or drink. Continuing to ingest anything after the onset of choke may worsen the blockage.
Colic: There are multiple types of colic, some of which are mild and will pass on their own, others that are more severe and life-threatening. Regardless, all suspected cases of colic require emergency medical attention to determine the cause and intervene if necessary. If left untreated, some forms of colic can be fatal. Prior to calling the vet, check the horse’s temperature, pulse, respiration, and mucous membranes, and listen for gut sounds. If the horse is standing or lying quietly, let it rest. If it is thrashing or behaving violently, attempt to walk or move it to an open space to avoid injury. It is very important to remove all food and water from the stall or paddock. Allowing the horse to ingest anything could further complicate an impaction or torsion, or rupture the stomach. Do not administer banamine or phenylbutazone unless advised to do so by the vet, as it may mask symptoms.
Ocular Trauma: It is impossible to ascertain the degree of damage present in a case of ocular trauma without prompt and proper evaluation from a veterinarian. Depending on the nature of the injury, there could be damage to the eyelid, conjunctiva, cornea, or lens, and in the case of a direct blow to the eye, there could be a fracture or retinal detachment. Left untreated or improperly treated, something as seemingly superficial as minor scratch on the surface of the eye (a corneal ulcer) can lead to a bacterial or fungal infection, and a loss of vision. Call the vet immediately and describe the condition of the horse’s eye as best as you can. It is very important to protect the eye from further damage and prevent the horse from rubbing its eye on anything. If the horse is accustomed to wearing one, put a fly mask on the horse to protect the eye from dirt, insects, and if outside, sunlight. Do not attempt to remove a foreign body embedded in the eye. If done improperly, the structure of the eye may collapse. It is also inadvisable to apply any ophthalmic ointment containing steroids (cortisone, dexamethasone, hydrocortisone). If the horse has a scratched or ulcerated cornea, a steroidal ointment may delay healing and increase the risk of infection.
Grain Overload: A horse that has consumed a large amount of food in a short period of time is susceptible to colic, laminitis, endotoxemia, and in severe cases, a ruptured stomach. Prior to calling the vet, check the horse’s temperature, digital pulse, respiration, and mucous membranes, and listen for gut sounds. Note the presence of any manure, the amount of food consumed and estimate the period of time in which it was ingested. This information will help the vet determine the urgency of the case. The most important thing to do is secure the horse in a stall with no access to food or water. Adding more food or liquid to any already distended stomach could cause further complications. Do not attempt to insert a nasogastric tube oneself. The tube passes through the nostril to the pharynx, which connects to both the esophagus and the trachea. It is vitally important that the tube is inserted correctly! Accidentally inserting the nasogastric tube into in the trachea and then administering mineral oil or liquid charcoal could be fatal.
Heat Stroke: When a horse’s rectal temperature exceeds 104.9°F (40.5°C) it is suffering from heat stroke and is highly susceptible to organ and brain damage due to the increased oxygen demand created by the hyperthermic state. If left untreated, heat stroke is fatal. Immediate veterinary attention is required to assess the presence and degree of damage to internal organs so treatment can begin as soon as possible and fluids can be administered intravenously. Prior to calling the vet, begin cooling the horse with water applied with a sponge or hose to lower the body temperature. Pay particular attention to the neck (large veins) and groin area (thin skin). It is imperative to immediately cease all physical activity and remove tack to initiate cooling. If is safe to do so and if shade is available nearby, move the horse out of the sun. Do not delay cooling. If cooling is delayed, the oxygen required by the horse’s metabolic system can exceed the amount produced by the respiratory system, resulting in a coma and/or death.
Hoof Puncture: Without a radiograph there is no way of knowing the depth or severity of the puncture and which structures of the hoof may be impacted. Depending on where the object entered the hoof, for example, in the case of a nail puncture in the middle of the hoof, the synovial structures (coffin joint, navicular bursa, deep digital flexor tendon sheath) could be affected. These cases are urgent! A puncture is also an easy way for bacteria to enter the hoof and if left untreated can lead to infection (sepsis, tetanus). Prior to calling the vet, move the horse to an area with clean, dry footing and clean the hoof. It is important to carefully clean and cover the sole of the foot with a protective bandage or clean boot to prevent further contamination of the area. Do not remove the object from the hoof before the vet can take a radiograph to see what internal structures are affected. Furthermore, attempting to remove the object oneself has potential to cause more harm, i.e. the end of the object may break off, making extraction more difficult. However, if the object is protruding past the bottom of the foot and will be impacted further by the horse stepping on it, it is advisable to gently remove the object and mark the entry point with a hoof knife or marker prior to covering the foot.
Lacerations and Puncture Wounds: Any laceration or puncture wound over a joint will require immediate attention because a) healing will be hindered by movement, and b) it is possible that synovial tissue has been penetrated, which would be indicated by the presence of a viscous, yellowish transparent fluid. Any wounds with prolonged or excessive bleeding require the application of a pressure bandage and also require immediate veterinary attention, as do wounds with gaping skin edges. Prior to calling the vet, note the location, general size, and nature of the wound. If there is excessive bleeding, the priority is to apply the pressure bandage, otherwise, it may be advisable to gently rinse the wound with clean water or a saline solution and apply pressure to reduce blood loss. Do not try to inspect the injury to see how deep or severe it is. Doing so may further damage and contaminate the tissue. Wait for the vet to do a proper and thorough cleansing of the wound, with sedatives if deemed necessary.
Sudden Onset Severe Lameness: Sudden onset severe lameness occurs when a horse is only able to bear minimal weight on a limb or is unable to move, which may be the result of a hoof puncture, subsolar hoof abscess, tendon or ligament injury, or most severely, a fracture. Prior to calling the vet, ensure the horse is calm and secure to prevent any unnecessary movement, which could exacerbate the injury. While many sources suggest trotting a horse to determine which leg is lame, this is not advised in cases of severe lameness. Do not force the horse to move! Doing so could cause further distress for the horse, increase damage to affected tissues, and in the case of a fracture, potentially displace the bones beyond the point of repair. The most important thing to do is keep the horse as still as possible, especially if a fracture is suspected to minimize further damage and distress. Do not provide pain-relieving medication to a horse with severe lameness, as further movement may cause further instability or damage if a fracture is present. It is also inadvisable to administer any anti-inflammatory medications if an abscess is suspected because the medication will reduce inflammation, thereby making the abscess less likely to open and drain, potentially leading to a severe infection.  
Acute Exertional Rhabdomyolysis: Commonly known as ‘tying-up’, exertional rhabdomyolysis can cause muscle necrosis and in severe cases, kidney failure. Veterinary attention is necessary within 24 to 48 hours of mild cases, and immediately in acute cases. In suspected acute cases, the vet will test blood levels for myoglobin, which is toxic to the kidneys, administer intravenous fluids to counter dehydration and flush toxins from the body, as well as assess the extent of both muscular and kidney damage. Blood serum levels will be tested again for creatine kinase (4 to 6 hours after the episode) and aspartate aminotransferase (18 to 24 hours after). Prior to calling the vet, if the horse is able to move without too much strain or distress, move it to a stall and ensure it has access to water. It is important to stop exercise at the first sign of exertional rhabdomyolysis to prevent it from worsening. In mild cases, a horse will experience slight muscle stiffness while in more acute cases, the horse may be completely unable to move. Do not force the horse to move if it is reluctant to do so. Exertional rhabdomyolysis can be a source of excruciating muscular pain (cramping) for the horse.
References

12: Pre-Purchase Exam

Action Point: Understand the value and limitations of the pre-purchase examination and the role of everyone involved (buyer, seller, veterinarian, trainer).

Rationale: Taking the time to become familiar with the standard procedures involved in a pre-purchase examination, the degree of information the veterinarian will be able to provide, and the importance of clear communication between all parties is an important first step in the examination process.

The Pre-purchase Exam: What to Expect

The Pre-Purchase Exam: A Practical Understanding of Today's Technology & Its Limitations

The Veterinarian's Role in Pre-Purchase Exams

Notes on Conformation

Beauty may be in the eye of the beholder, but good conformation is a matter of physics.  A horse that is well-built for his job will stay sound and perform better than one that has poor conformation. – J. Landels

Ideal Conformation: Head-to-Tail-to-Toe

(From: Xenophon Continued: Notes on Conformation)

Head: Proportional to the size of the body, long with well defined features and ample room for the nasal passages teeth, tongue and top of the windpipe. The angle where the head meets the neck must not be too acute, otherwise it may restrict the horse’s breathing by compressing the larynx.

Jaws: Strong and broad with sufficient width between the jaws to accommodate the large amount of airflow required for optimal respiration. To ensure proper grinding of food and even wear of the teeth, the jaws should meet evenly and have good up-and-down and side-to-side motions.

Eyes: Horse’s with deep-set eyes may have a slightly limited field of vision. Prominent, round eyes that are widely-spaced at the sides of the head enable horses to see nearly 360 degrees. The eyes should also be bright, clear, alert, and intelligent in appearance. Eyes that are dark brown in colour may be preferable, as blue and green eyes are more photosensitive.

Ears: Ears should be proportional in size to the head. If they are too long, the horse is said to have mule ears, too far apart or droopy, they are considered lopped. Either way, this is generally of minimal concern. 

Muzzle: The muzzle should be small with large, open, thin-walled nostrils to intake large volumes of oxygen. Firm, muscular lips are needed to select and grasp food.

Neck:  The neck, although slender, should be muscular and slightly arched along the topline, from withers to poll, with a straight underline.

Withers: Well-defined, medium high, sloping withers usually indicate longer shoulder muscles, which allow for increased extension of the forelegs and freer movement of the hindlegs. They also help keep a saddle in place.

Chest: Well-defined and fairly wide, without being extremely wide or overly narrow. An overly narrow chest will result in the forelegs being too close together, and too much width will cause a rolling motion when the horse is in motion. A slight pectoral bulge should be visible from the side.  

Forelegs: Long, sloping shoulders, angled toward the front to meet the upper arm, which angles toward the back to meet the forearm, then straight down from the elbow to the fetlock, where the foreleg angles toward the front again through the pastern to meet the hoof. The angles of the shoulder, pastern and hoof wall should be equal to maximize shock-absorption.

Back: The back should be relatively short, straight and wide to support the weight of the horse’s ribs, muscles and organs, as well as the weight of a rider while allowing the horse to maintain balance.

Loin: The loin plays a key role in impulsion and is most effective at supporting the lumbar vertebrae and transferring power forward from the hindlegs when it is short and well developed.

Barrel: The barrel should be deep and wide to accommodate the horse’s large heart and expanding lungs with a spacious rib cage to protect them, along with the internal organs. Backward sloping, largely-spaced ribs allow for full expansion of the lungs.  

Hind legs: Providing most of the power for locomotion, the hind legs also absorb a great deal of concussive force.  Well muscled and strong, the angles of the stifle and hock are less than those of the shoulder and upper arm. The point of buttock, point of hock, and back of the cannon should line up with one another in a straight line.

Hindquarters: Appearing square and symmetrical when viewed from behind, with a rounded croup, the muscular, powerful  hindquarters play a key role in moving the horse.

Feet: Well-proportioned and set squarely on the legs with rounded toes and broad heels, the feet should be balanced and symmetrical, allowing for even distribution of concussive forces.

Hooves: See Hoof Anatomy.

Equine Research. (2004). Horse Conformation: Structure, Soundness, and Performance. Guilford CT: The Lyons Press.

Hood, D.M. and C.K. Larson. 2013. Building the Equine Hoof. Eden Prairie, Minnesota: Zinpro Corporation.

11: Cardiovascular Health

Action Point: Be aware of the signs that may indicate cardiovascular problems in the horse.

Rationale: Heart problems are not common in horses, however, they are not immune to them. If any of the following changes are observed in a horse, it may be an indication of a cardiovascular problem.

  • Loss of condition
  • Increased fatigue during exertion
  • Shortness of breath
  • Increased rate or effort of breathing
  • Weakness occasionally resulting in collapse or fainting
  • Signs of fluid accumulation in the abdomen or beneath the skin of the lower thorax

Heart murmurs are generally the most common, and in most cases benign of the cardiac disorders that can afflict horses. The majority of heart murmurs are physiologic, or normal, and can occur in conjunction with an excited state or a bout of colic. More serious cases could be caused by turbulence or increased velocity of blood flow due to a leaky heart valve. A specialist will be able to determine whether a heart murmur is considered incidental or merits further examination.

Horses can also be affected by congenital heart defects that are present at birth. Though these are much rarer in horses compared to humans and dogs. The first sign of a congenital heart defect is usually a murmur heard within the first few weeks or months after birth. These include ventricular septal defect (a hole in the heart) and patent ductus arteriosus (which will resolve on its own in most cases) – again, congenital heart defects are very rare in horses. 

Degenerative or acquired heart disease, such as arrhythmiasatrial fibrillation, and valvular heart disease may occur in horses older than 5 years of age, and very rarely in younger horses. Although still relatively uncommon, acquired heart disease has a slightly higher frequency of occurrence relative to congenital heart defects.

Myocardial disease is toxic damage to the heart muscle following an infectious disease like strangles, influenza or an internal abscess, and in rare cases a severe dietary deficiency of vitamin E or selenium, or the ingestion of a toxic chemical found in cattle feed.

Thrombophlebitis, a firm clot in a small part of the jugular is the only vascular condition that affects horses. It is usually the result of repeated trauma to the jugular from repeated puncture of the vein, injections or use of a jugular vein catheter.

Aorto-iliac thrombosis is a condition that affects the hind limbs, resulting in signs of lameness, stiffness, weakness and abnormal gait. The result of a clot that forms where the abdominal aorta branches toward the hind legs, this condition is progressive and rarely reversible.

The Equine Power Plant Unequaled!

*refer to summary of article in Functional Anatomy - Week 5: Activities

11: Infectious Respiratory Diseases

Action Point: Understand the most common infectious respiratory diseases and how to prevent them from occurring.

Rationale: Respiratory conditions are fairly common and can have a significant impact on individual horse health and performance and, in the case of infectious diseases, can be easily spread. Prevention is the best measure in ensuring respiratory health.

Management decisions play a significant role in maintaining respiratory health and protecting horses against infectious disease. Best practices include, developing a vaccination schedule in consultation with a veterinarian, and implementing biosecurity protocols, i.e. isolate all newly arriving horses, and isolate horses with clinical signs immediately.

Respiratory  system diseases fall into two categories. (1) Infectious upper respiratory tract disease (IURD) primarily affect young horses and often occur in the form of an outbreak. The most common IURD conditions to be aware of are equine influenza virus, equine herpes virus, equine rhinovirus, sinusitis, and strangles. (2) Infectious lower respiratory tract disease (ILRD) affect any age of horse. Includes pleuropneumonia, lungworm, and parascaris equorum.

Respiratory Diseases in Horses: What You Can Do to Prevent Them

Slater, J. D. & E.J. Knowles. (2012). Ch. 14: “Medical nursing.” In K.M. Coumbe (Ed.), Equine Veterinary Nursing. p.246-285 John Wiley & Sons Incorporated 

Future post: non-infectious respiratory system diseases

10: Develop an Equine Wellness Program

Action Point: Develop equine wellness programs for each horse based on their individual needs.

Rationale: Developing equine wellness programs in consultation with a veterinarian will ensure routine care and monitoring of each horse’s health and serve as a proactive tool in disease prevention and early diagnosis and treatment.

The following elements should be included:

  • routine immunization
  • parasite control
  • nutritional consultations
  • annual Coggins testing
  • dental care
  • annual physical examination
Is Your Horse Enrolled in a Wellness Program?

Designing an Equine Wellness Plan for Your Practice

Zimmel, D. (2009). Ch. 5: “Equine Wellness Program.” In AAEVT Equine Manual for Veterinary Technicians. p.131-146. Wiley-Blackwell

10: Protecting the Horse’s Skin

Action Point: Learn about the most common skin conditions in horses, how to prevent, identify, and treat them (in consultation with a veterinarian).

Rationale: Skin conditions, although not usually fatal, can cause a great deal of discomfort and affect the quality of life and performance abilities of a horse. They may also be an indication of disease, which may be contagious, and in some cases, zoonotic, that is, transmissible from horse to human. Common causes of skin irritation in horses are allergens, environmental factors/exposure, external parasites, and in some cases, management practices.

Common skin conditions

  • Hives (urticaria) – may be acute or chronic depending on the cause
  • Atopic dermatitis – airborne allergens
  • Sweet itch (insect-induced dermatitis) – Culicoides aka “no-see-ums”
  • Pemphigus foiaceus – autoimmune disease
  • Bumps/nodules – insect bites
  • Rain rot/rain scald (dermatophilosis) – bacterial, contagious
  • Mud fever/scratches (pastern dermatitis) – bacterial or fungal
  • Alopecia
  • Photo-sensitivity/sunburn
  • Warts and sarcoids
  • Ringworm (dermatophytosis) – fungal, contagious
  • Mange – mites
  • Lice

Prevention tips

  • Keep horses clean and dry
  • Avoid keeping horses in wet, muddy pastures
  • Parasite control – internal and external
  • Pasture and manure management
  • UV protection
10 Common Skin Conditions

Equine Dermatology - Everything You Wanted to Know (and More) About Skin

Diagnosing equine skin disease

Structure of the Skin in Horses

09: Recognizing the Signs of Colic

Action Point: Make sure everyone involved in the care and management of the horses is familiar with signs of colic and what to do when they are observed.  

Rationale: Signs of colic can range from subtle to obvious and it is important for everyone involved in the care and handling of horses to be aware of them. Early detection and immediate veterinarian attention is important to distinguish between medical cases, which make up about 90% of incidences, and surgical, which can be fatal if not attended to soon enough.

Signs:

  • Flank watching (turning head toward flank)
  • Pawing
  • Kicking at or biting belly
  • Stretching out as if to urinate
  • Repeatedly lying down and getting up or attempting to do so
  • Rolling repeatedly
  • Sitting in a dog-like position or lying on the back
  • Holding rotated to one side with an outstretched neck
  • Not completely a meal or showing complete disinterest in food
  • Lowering the head toward water without drinking
  • Reduced or absent gut sounds
  • Inappropriate sweating
  • Rapid breathing and/or flared nostrils
  • Elevated pulse rate >50 beats per minute
  • Depression
  • Lip curling

What to do:

  1. If colic is suspected, immediately call the veterinarian
  2. Remove all food but make sure the horse has access to water
  3. Keep a close watch on the horse to observe signs and changes in behaviour
  4. If the horse is continually rolling or thrashing, it is advisable to walk it if it is safe to do so. If the horse is resting quietly, leave it be
Colic: Minimizing its Incidence and Impact in your Horse