Assessing Your Horse's Vital Signs
by Debora Johnson
You have decided that you want to assess you horse's vital signs and now you have to determine how to do that. Just what does that mean, "vital signs?"
Most of the time when one thinks of vital signs the heart rate, temperature and breathing rate are what comes to mind. Actually, that is not the entire picture. There is much more than those three specifics vital signs that must be observed and checked. There are both physical and non-physical vital signs that must be entered into the evaluation. It is my hope that the following will be a help to you. It is what I consider with our horses.
Physical Vital Signs of Your Horse
- Do A Visual Review- Your horse's demeanor (bearing, deportment, manner, carriage mean the outward manifestation of personality or attitude. bearing is the most general of these words but now usually implies characteristic posture. Deportment suggests actions or behavior as formed by breeding or training. Demeanor suggests one's attitude toward others as expressed in outward behavior. Manner implies characteristic or customary way of moving and gesturing and addressing others. Carriage applies chiefly to habitual posture in standing or walking. For example, is your horse off his feed? This is a big red flag! Does he show signs of depression? Is he listless? Is he standing in an unusual posture, pointing or extending a hind limb, favoring a front limb, rocking in place or front and hind legs extended while standing (not during urination which is normal). This can be an indicator of pain, lameness, or even laminitis or founder. Does your horse not want to be touched? Does he lay his ears back or try to kick or bite you which is not a normal state of affairs? Is your horse refusing to move, just standing with a blank stare, kicking or biting at his belly or flanks? This could be a sign of colic or some other sort of gastrointestional distress. Is he pawing or chewing (cribbing) on stationary objects or on himself? These behaviors can often be a symptom of pain. Does your horse show any signs of rubbing his head or his rear? Are there scratches, lost or fussed up hair on his tail, mane or face? Rubbing can be a sign of allergies, parasites or the need for a gelding to have a sheath cleaning as well as other possibilities. What do you notice that is unusual behavior for your horse? Make a mental note of that. Then assess it.
- Respiratory System and Cardiovascular System - The heart rate can be determined by feeling for the pulse along the lingual artery, under the jaw, where it lies just under the skin and on the bone. You can also listen to the heart at the point of the elbow on the left side with a stethoscope. The normal heart rate for a horse is approximately 30 to 40 beats per minute. Watch the rib cage and note the number of times the horse inhales and exhales in a minute, feel for the breaths at the nostrils, or listen to the breaths in the windpipe. I have a stethoscope to do the latter. Look at your horse's nostrils. Are they flared when it inhales? Is there air moving through both nostrils? Is there any noise being generated as the horse breathes? Is there any sign that your horses is laboring to breathe? The normal respiratory rate for a horse is eight to 12 breaths per minute.
Look at the gum color (should be pink) and moist. Bright red, dark red, bluish, or white gums are considered abnormal. (Very Pale Pink: Capillaries contracted, indicates fever, blood loss or anemia. Bright Red: Capillaries enlarged, indicates toxicity or mild shock. Gray or Blue: Severe shock, depression and illness. Bright Yellow: Associated with liver problems.) Press the gum line next to the teeth with your finger. The capillary refill is quick (about 2 seconds). The white spot you created when you pressed the gums with your finger should turn pink again when the blood returns to that spot. Note: The horse is the only mammal, other than humans, that cools himself by sweating. High ammonia levels have been associated with respiratory problems in foals and other animals.
- Body Temperature - A horse's normal body temperature varies between 37.5 Celsius = 99.5 degrees Fahrenheit and 38.5 degrees Celsius = 101.3 degrees Fahrenheit.
I use a rectal thermometer with a string attached to it and leave it inserted in the horse's rectum for 3 minutes. Then I check the results. I always feel my horse all over with my hand to see if I detect any heat or swelling anywhere. Heat often is an indication of infection or inflammation. Both are possible trouble signs. Note: Horses are most comfortable at temperatures between 18 degrees if the horse has a winter coat and 59 degrees if the horse has a summer or wet coat.
- Shock - If your horse is in shock it can be fatal. Pain, infection, trauma, major fluid loss, fear, colic and dehydration are often triggers of shock. The circulatory system can shut down resulting in organ failure and death. The horse may exhibit rapid breathing, shaking and shivering, weak pulse, pale or blue gums and cold ears and legs. Call the vet immediately!
Electrolytes/Dehydration and Horses
- Hydration or Dehydration? - Dehydration is the loss of body fluid. The body is composed of about 70-80% water in the normal adult horse and even more in the young. This fluid is found inside the cells (intra cellular) and outside the cells (extracellular). Only a few percentage points loss of fluid is life threatening. At about 12% loss of body fluids death occurs. The actual percentage of dehydration is difficult to determine, it can be estimated by the packed cell volume (PCV) and by checking the skin turgor.
Skin turgor refers to the elasticity and "feel" of the skin. As the animal becomes dehydrated the skin becomes less elastic, it does not snap back when pinched, and is described "as doughy." When dehydration is severe the skin actually tents (remains in the tented position for seconds before flattening out) when pinched.
Other ways to determine dehydration include checking mucous membrane (gums) for moistness and noting if the eyes are sunken (this is a grave sign!) Vet 105 Introduction to Veterinary Technology
Non-Physical Signs to Assess
- Environment - The average 1,000 pound horse produces 45 pounds of fecal matter each day. An average, 1,000 pound horse produces 2.4 gallons of urine a day. He drinks about 6-10 gallons of water per day or about 5% of his body weight. A good rule of thumb is that a horse needs at least a gallon of water per 100 lbs of body weight. For your average horse, this equals 10 gallons a day. Water requirements vary greatly according to the weather and the level of work that the horse is doing. For instance, if your horse is exercising in hot, humid weather, he may need 2-4 times the minimum amount. Do you see that his system is working correctly? Does his stall or pasture area indicate that all is well? Is your horse defecating and urinating? Is there any sign of blood or other fluids such as mucous that are unusual? Is he off his feed? Is he drinking water?
Any red flags that you may have should be investigated immediately. Just like humans, horses do not all respond the same way to physical or psychological disorders. You know your horse better than anyone. Your acute perception of your horse may save his life. See also my article on: Horse Vital Signs