What are normal numbers and indications for vital signs?
- Temperature: An adult horse's normal rectal temperature is 99.5 to 100 degrees F (37.5 to 37.8 degrees C). A foal's temperature will range from 99 to 102 degrees F (37.2 to 38.9 degrees C)
- Pulse Rate: An adult horse's resting pulse rate will range from 35 to 45 beats per minute. A nursing foal's pulse rate at one month of age is 70 to 90 beats per minute.
- Respiratory Rate: Normal rate averages 12, but will range between 10 and 30 breaths per minute.
- Capillary Refill Time: This is an indication of blood circulation. Normal refill time is 1 to 2 seconds.
- Mucous Membranes: The mucous membranes line the horse's eyelids, gums and nostrils, and the color is another indicator of blood circulation. A healthy horse's mucous membranes are moist and pink.
- Dehydration: Healthy horses drink a minimum of 5 gallons of water a day. If a horse refuses to drink or goes too long without access to water, severe problems can develop.
- Gut Sounds: Absence of gut sounds can indicate colic or other serious conditions.
How to check vital signs
Temperature: To take a horse's temperature, first tie the horse or have someone hold his head. Stand beside (not in back of) the left hind leg, lift the tail slightly to the side with your left hand, and insert the tip of the thermometer a couple of inches into the rectum with your right hand. Generally, you don't need to use any sort of lubricant, and most horses don't object to the procedure. It's still wise to keep a tight grip on the thermometer! When the temperature has stabilized, remove the thermometer and read the result.
Bulb and digital thermometers are equally suitable, but many horse owners prefer low-cost digital thermometers because they are easier to use and safer for the environment. If using a traditional bulb thermometer, shake it down until the bulb registers below 96 degrees F or 35.5 if C. Some thermometers made especially for use with horses are longer and have a safety attachment to hold onto and are also relatively inexpensive, making them a good investment.
With a traditional bulb thermometer, wait 3 minutes, then remove the thermometer and wipe it clean. Read the temperature by the height of the silver or red column of mercury on the scale.
If using a digital thermometer, follow the manufacturer's directions or follow instructions for traditional bulb thermometer remembering that you will get an accurate, easier-to-read reading more quickly with a digital thermometer.
Pulse: The horse's pulse can be taken at any point where a large artery is located beneath the skin. A convenient place is where the external maxillary artery crosses the lower border of the jawbone.
To locate the pulse, press lightly with the balls of your fingers. The pulse is most notable when the horse has been exercise, but you should become familiar with both the horse's resting rate and the rate after being exercised.
The pulse can also be taken at the inside back of the knee which corresponds to the wrist in humans.
Respiratory Rate: Determine the horse's respiratory rate by observing and counting the movements of the nostrils or flanks.
When you suspect that your horse is ill or if the horse is injured, one of the first questions your veterinarian will ask when called, is "What are the horse's vital signs?" Practice taking your horse's vital signs and keep a record of what is normal for each horse.
Capillary Refill Time: Lift the horse's upper lip and press your thumb firmly against the gums to create a white mark. Remove your thumb and watch for the return to a normal pink color within 1 to 2 seconds after releasing the pressure.
Mucous Membranes: The color the the mucous membranes indicates much about the state of the horse's health. A healthy horse's mucous membranes will be a slightly lighter pink than a human's.
Very pale pink membranes indicate contracted capillaries that may be a result of fever, blood loss or anemia.
Bright red mucous membranes mean that the capillaries are enlarged and may indicate toxicity or mild shock.
Grayish, bluish mucous membranes are the result of severe shock, depression, or other illness.
Bright yellow or yellowed mucous membranes are associated with liver problems.
Dehydration: The pinch test has been the standard test for dehydration in horses for decades. To perform the pinch test, simply pinch the skin on the horse's neck and observe how long it takes the skin to flatten back into place after you let go. If it flattens within 1 second, the horse is fine. If it takes longer, the horse is dehydrated.*
Other signs of dehydration include dry mucous membranes in the mouth and sunken eyeballs.
Gut Sounds: To check for gut sounds, press your ear against the horse's barrel just behind the last rib. If you hear gurgling sounds, your horse is fine. If you don't hear the sounds on one side, check the other side.
*Some research questions the validity of the pinch test, since results can vary depending on the moisture in the horse's coat, the side the test is done on, and other factors. Some veterinarians believe that keeping track of the amount of water a horse drinks per day while taking into consideration air temperature and exercise factors, is more valid than simply using the pinch test.