Normal parameters and vital signs

Knowing what your horses normal vital signs are is very important as these can be a very good indicator of how your horse is feeling and if he needs veterinary attention. You should check your horses vital signs on a regular basis – once a week is ideal as well as when you think your horse might be off colour.

Vital signs are measures of a range of physiological statistics. Those vital signs normally assessed in the horse are body temperature, heart rate, respiratory rate, gut sounds, hydration status and blood circulation (capillary refill time and mucous membranes). Normal parameters are those ranges that indicate your horse is healthy; anything outside of these ranges might indicate a problem and veterinary attention should be sought immediately.

The normal body temperature for a healthy adult horse at rest is between 37.5-38.5°C / 99.5-101.4°F . This temperature can vary by 3 degrees depending on environmental factors, i.e. horses will tend to have a higher temperature in warmer weather and during or after exercise, and a lower temperature in cold weather. Temperatures also tend to be higher in the afternoon. If you need to monitor your horses temperature on a daily basis, make sure you take the temperature at the same time every day to avoid inconsistent readings.
The most common way of taking your horses temperature is rectally. When taking your horses temperature you should use a large rectal thermometer which is thick and less likely to break if it is dropped; plastic digital thermometers are very common today and are available at most tack shops – they work very well and are easy to use, they also beep once the maximum temperature is reached.
When taking your horses temperature, firstly make sure the thermometer you are using is clean. Stand next to your horses rump and face the tail, lift up the tail and gently insert the thermometer slightly angled downwards. Leave the thermometer in place for about 3 minutes, or if you are using a digital thermometer, until it beeps. Gently remove the thermometer when ready and take the reading immediately.
Make sure you clean the thermometer thoroughly before putting it away, especially if you think your horse might be ill to prevent spreading disease.

The normal heart rate for a healthy adult horse at rest is between 30-40 beats per minute (bpm). A rate of 50 bpm or above could mean the horse is in distress. Young horses up to about a year of age tend to have slightly higher heart rates at around 70-80 bpm. If your horse has been exercised, is excited, nervous, in pain or ill, his heart rate will increase. If in pain or ill, the higher the heart rate is, the more severe the condition will be.
You can check your horses heart rate by feeling his pulse or by using a stethoscope. Your horses pulse can be found near the front of the left jawbone; use your forefinger to locate the carotid artery don’t use your thumb because you will feel your own pulse! press this firmly, and using a stopwatch time a 15 second period, and count the number of beats you feel, multiply this by four to calculate your horses bpm.
When using a stethoscope, place the scope on the left side of the chest, just behind the elbow of your horses front leg, as shown in the picture, and listen carefully. Time the beats in the same way as explained above.

The normal respiration rate (number of inhalations OR exhalations) for a healthy adult horse at rest is between 8-12 breaths per minute . If your horse has been exercised, is excited, nervous, stressed, in pain or ill, his respiratory rate will increase. A rate significantly above this in a resting adult horse would be cause for concern. Immediately after birth a foals respiratory rate can be as high as 60-80 breaths per minute; in the first week of its life this will reduce to 20-40 breaths per minute.
Your horse’s respiratory rate should never exceed his heart rate, if it does there is a serious problem and you should call your vet immediately.
Respiration rates can vary widely between horses, so it is a good idea to take your horses respiratory rate when you know he is well so you can use this as a comparison if you are ever concerned for your horses health. The best way of measuring your horses respiratory rate is to stand in front of him but slightly to one side and count the number of times his ribs move either in or out, not both!!!!! If you have access to a stethoscope, you can listen to your horses breaths by placing the scope over the trachea (the underside of the horses neck).

The normal gut/intestinal sounds for a healthy adult horse should include a wide range of sounds from gurgling and rumbling to squeaky noises. Gut sounds are very important indicators of gastrointestinal problems if you are unable to hear any sounds this is an indication of colic and you should call your vet immediately. Excessive gut sounds (continuous rumbling) can also be a sign of a problem; this is usually accompanied by diarrhoea. You should also call your vet if you notice a change in gut sounds accompanied by other signs such as distress, pain, fever or loss of appetite.
Using a stethoscope to listen to your horses gut sounds is the easiest way; place the scope on your horses flank behind the ribs and forward from the stifle joint, firstly on the upper right quadrant, then the lower quadrant, then both the upper and lower quadrants of the left side. Listen for a few minutes for a complete cycle of sounds on each quadrant. This can also be done without a stethoscope by placing your ear against the horses flank instead although not ideal, you will still be able to hear if gut sounds are present or not.

A normal healthy adult horse will consume approximately 22.5 litres / 5 gallons of water per day. It is important to monitor how much water your horse drinks when stabled and when out at grass; if you notice your horse is not drinking or is drinking excessive amounts of water there could be a problem. If your horse is dehydrated, this means he isnt consuming enough water and you should try and encourage him to do so. This can be achieved by adding flavour to his water such as apple juice or adding a small amount of salt or electrolyte to his feed which should encourage him to drink more. Excessive drinking on the other hand can be caused by conditions such as Cushings disease or kidney problems. If you are unable to get a horse to drink or your horse is drinking excessively you should contact your vet who will be able to help.
There are two tests to help determine if your horse is dehydrated or not. The simple pinch test involves pinching a piece of skin of between 15-20 mm near the point of shoulder. When you release the skin it should return to normal almost immediately, if it returns to normal slowly, then this could be a sign of dehydration, although recent research suggests this can be affected by other factors and is not as reliable as once thought.
Hydration status can also be established by testing Capillary Refill Time (CRT) see below.

Blood circulation can be established by testing CRT; this is the time it takes for the gums, which have been blanched by finger pressure, to return to a normal pink colour. This should take no longer than 1-2 seconds in a normal healthy horse. If it takes longer than this, it is an indication of poor blood circulation and can also be an indication of dehydration. Lift your horses lip up, and using your thumb press on the gum for 2 seconds, this squeezes the blood out of that area, as soon as you take your finger away the blood should return to the area within a couple of seconds.
Checking the colour of your horses mucous membranes (lining of eyelids, gums and inside of nostrils) is also another indicator of blood circulation. A normal healthy horses mucous membranes are pale pink (paler than humans). If your horse has very pale, red, purple, yellow, blue or any variation in between, you should call your vet immediately. Abnormal mucous membrane colour can be an indicator of poor blood circulation among other problems such as blood toxicity and liver problems.

Body temperature

  • 37.5-38.5°C / 99.5-101.4°F

Heart rate

  • 30-40 beats per minute (bpm)

Respiratory rate

  • 8-12 breaths per minute

Gut sounds

  • Should include a wide range of sounds from gurgling and rumbling to squeaky noises

Hydration status

  • 22.5 litres/5 gallons of water per day
  • Pinch test – skin should return to normal immediately

CRT

  • 1-2 seconds

Blood circulation

  • Mucous membranes should be pale pink in colour