Know Your Horse’s Norms
How to Take, Measure and Track Key Vital Signs
By Meriel Moore-Colyer
Maintaining good health in our horses is every owners’ responsibility. Avoiding performance limiting viruses, preventing the development of more serious diseases and ensuring your horse is content and living as natural a life as possible should be everyone’s top priority.
Objectively monitoring your horse’s health on a daily basis will make you acutely aware of his ‘normal’ vital statistics and improve your ability to detect any emerging problems. It will also help you build a better understanding of physiology and deepen your connection with your horse.
Alongside the normal subconscious observational overview that we all do each morning, (pricked ears, eating normally, interested in life, clear eyes and clear nostrils) there are several objective signs of good health that are easily monitored. When taking the following measurements, make sure you do these before exercise or several hours after the work session, so you are truly measuring resting values.
Pulse rate is an easy and accurate indicator of heart rate. Normal pulse rate is approx.30-40 beats/minute, although your horse may be slightly outside this range. Daily monitoring will help you establish what is normal for your horse, but a variation of 5 beats/minute is normal.
Take the pulse with your fingers lightly pressing on the mandibular artery just under the big cheek bone. It is easiest to count the pulses for 15 seconds and then multiply by 4. As a horse gets fitter the resting HR will slow slightly, although not as much as occurs in fit humans.
A small rise in heart rate may indicate some external stimulation/excitement/anticipation so take the pulse during quiet times and initially a few times each day, until you find the ‘norm’ for your horse. A rise above 40 beats/minute should be monitored carefully as this is likely to indicate pain.
If it remains high throughout the day, then veterinary attention should be sought. A ‘resting’ HR of 60 beats /minute should send you running for the phone – because your horses is severely ill.
The normal range for a horse at rest is 99 to 101oF or 37.2 to 38.3oC. Again, environmental conditions can alter this slightly with a rise of approx. 3oF during very hot weather. Stress and exercise will also cause a slight rise.
Take the temperature initially several times a day to find the norm. Taking the temperature is best done rectally. Stand slightly to the side behind your horse and gently move the tail to one side. Using a lubricated thermometer, gently inset into the rectum slightly to the side. It is best to lightly press the thermometer against the side of the rectum to ensure you are recording the body temperature and not the temperature of the faeces.
The length of time you hold it there will depend on the type of thermometer, (a mercury thermometer takes approx. 3 minutes). If you are using a mercury thermometer, make sure you shake it well before inserting. Whatever type you use, hold on tight, especially the first few times you do this, as many horses have a reflex action that can suck the thermometer into the rectum very quickly! Clean the thermometer thoroughly after each use.
A rise above 102oF is cause for concern, so call your vet.
4. Gut Sounds
Digestion in the horse is a highly dynamic process and should have a constant flow through it, maintained by trickle feeding in one end and frequent defecation from the other!
As the gut is essentially a large fermentation tube, it should be continually moving and gurgling. You can easily hear this by putting your ear to the flank. Absence of these gut sounds may be an early indication of colic. Because colic is still the biggest cause of death in horses across the globe, monitoring gut activity is of utmost importance.
Faecal outputs in horses can alter in consistency and colour according to diet, and some horses will defecate more than others. When horses are turned out onto lush pasture faeces often become soft, wet and dark green, while those produced on conserved diets commonly look brown and expelled as softish round balls.
Faecal dry matter (DM) can alter between 18 – 35% DM, and the book value will say that an average horse should be producing 8-12 faecal outputs in 24 hours. However, every horse and pony I have ever owned/monitored/used in experimental trials, have all defecated much more than that! Again, get to know what the norm is for your horse.
5. Feed and Water Intake
We all subconsciously measure feed intake, but do you take note of the amount of water your horse drinks? Are you also aware of any partially chewed feed on the ground? A reduced feed intake may be due to a rise in environmental temperature and nothing to worry about, but it could indicate a problem with his teeth.
Going off feed altogether is always a sign of something serious. My dressage horse loved his hay, but after a long road and boat trip from Ireland to the UK, and despite several rest stops, he developed travel sickness. The first thing I noticed was him not eating his hay, so I immediately called the vet and the early treatment of this potentially serious condition, meant he was fully recovered in 24 hours.
6. Mucous Membranes
The colour of mucous membranes (eyes, lips, gums and nostrils) should be a healthy light pink, which shows good circulation and hydration status (more on hydration next time). Checking circulation (capillary refill time) can be done by pressing the gums on the upper jaw, releasing it and counting how quickly the blood flows back into the area, it should do so in 2 seconds.
Mind your fingers! Horses and particularly ponies, as I know from collecting saliva samples, have an amazing capacity to quickly trap unsuspecting fingers!
7. Make Monitoring A Habit
Monitoring daily signs of good health in an objective way is a really good habit to form. As with weight management, seeing our horses every day makes it hard to notice small changes, but if you have to stop and think about measuring and recording something you pay much closer attention.
When you start this process don’t worry if values fluctuate a little. You will need to do this for a couple of weeks before you learn your own horse’s levels. It’s all about learning what is normal for your horse.
Try to make these measurements part of your daily regime, jot them down on a chart so you get a good indication of how your horse alters according to season, fitness, and everyday activities. Breed and size make little difference in any of the above statistics, it is more likely to alter slightly according to environmental temperature, work and fitness levels.
So, get measuring and know your horse inside out!
Author Meriel Moore-Colyer is an equine science professor and equine nutrition expert.