Knowing how to check your horse’s vital signs could one day save its life. Neil Clarkson reports.
Horses have their bad hair days, just like the rest of us.
They are unfortunately unable to tell us whether they’re unwell or just in a grumpy frame of mind.
That’s why owners need a thorough knowledge of six simple tests that can determine whether you should be on the telephone to your veterinarian.
The tests take only a few minutes, and should give you a clear idea of the general wellbeing of the animal.
The only tool that’s really necessary is a rectal thermometer. A stethoscope isn’t necessary, but for most horse owners it would be a wise investment.
Opt for a plastic thermometer. Digital versions that give a readout in a matter of seconds cost only $NZ15 to $NZ20. A stethoscope can be bought off the likes of internet auction sites for about the same money. We’ll explain how to use the stethoscope later.
Here are the tests:
We’re going to get the pulse from the artery that follows a path underneath the cheekbone. There’s one on either side of the head. Using three fingers, press inwards and upwards, and you should detect the pulse. The horse will need to be at rest for the pulse rate to be useful. If you can’t find the pulse there, try the foreleg, level with the knee joint (see the picture).
Temp – 37-38º in am; 38.5º in pm; slightly higher in foals and warm weather
Pulse – 36-38 beats per minute
Capillary refill – 1-2 seconds
Respiration – 8-16 per minute
Be sure to use your fingers and not a thumb, as the thumb has its own pulse and might provide some confusing data! Once detected, count the pulse for 30 seconds and multiple the number by two. The resting pulse should be somewhere between 30 and 40 beats a minute.
You should call your vet immediately if the resting pulse is 60 or above, or if you felt that the pulse was irregular or weak.
There’s no point popping your hand in front of the horse’s nostrils to count breaths as this is simply an open invitation for the animal to have a sniff. Stand about 30cm from the animal’s shoulder and look at the curve of the flank in front of the stifle joint. From here, you should see the rise and fall of the belly with each breath. Count the number of breaths for one minute.
A “normal” result will vary widely, depending on the size of the horse and air temperature. Expect a respiration rate between eight and 16 breaths a minute. Anything above this in a resting horse would be cause for concern. Just as significantly, check if the horse’s breathing appears laboured. Is it forcing each breath out, or are the breaths short? If so, it could be a sign of a lung infection or Chronic Obstructive Pulmonary Disease (Heaves). Do the nostrils seem flared or is there chewed food in the nostrils? In all such cases, contact your veterinarian.
Given the wide variation in breathing rates, a horse owner would be wise to get the breathing rate of their horse when they know it is well, doing several tests across warm and cold days to get some figures that can then be used as a yardstick if you later suspect your horse is unwell.
You’re unlikely to do any harm with a lubricated plastic digital thermometer, but you need to make sure you don’t get kicked. It won’t be any horse’s idea of a good time.
Read the instructions with the thermometer carefully to ensure you use it in a way that provides an accurate reading. Stand next to the horse’s rump and face the tail. Lift the tail and insert the thermometer. Remove as per the manufacturer’s instructions. Most digital thermometers will beep when they have recorded a reliable reading. A normal temperature is between 99.5 deg and 101.4 deg Fahrenheit, or 37.5 deg and 38.5 deg Celsius.
You would be wise to telephone your vet in the event of any elevated temperature to discuss the possible cause, but anything above 104 deg F or 40 deg C is cause for serious concern. Likewise, if your horse seems cold but is sweating.
Bear in mind that a horse’s temperature can change a little throughout the day, and is usually a little higher in the afternoon than the morning.
If you’re monitoring your horse’s temperature on a daily basis, be sure to take its temperature around the same time each day.
Hydration level tests
There are two tests to help determine whether a horse might be dehydrated. The first is more reliable than the second, and involves measuring the capillary-refill time. Use your thumb to press on a spot on the horse’s gum just above a corner incisor, which will squeeze the blood out of the area. Remove your thumb and time how long the blood takes to return to the area. It should be two seconds or less. If it takes three seconds or longer, the horse is likely to have a hydration issue. If the gums are discoloured – pale yellow, pale blue, or dark red – talk to your vet.
The second hydration check is a simple pinch test, but recent research (2008) suggests this can be affected by many factors and is an unreliable measure. Pinch a piece of skin near the point of the shoulder, so that the fold between your fingers is between 15mm and 20mm high. Release it and see how quickly the skin returns to normal. If the fold is slow to return, the horse may be dehydrated.
This can be done with or without a stethoscope. We’ll do it first without. Stand at the horse’s side and grab hold of the mane with your hand nearest the horse and lean over, placing your ear against the horse’s stomach behind the ribs and forward of the stifle joint. You should be hearing a wide assortment of sounds, from gurgles and squeaks to rumblings. Repeat the exercise on both sides of the horse. If you’re hearing only faint and infrequent gut sounds, call your veterinarian immediately on suspicion of a case of colic.
Using a stethoscope propels you into a whole new ballgame. Firstly, once armed with one, you need to listen to your horse’s normal gut sounds when you know the animal is well. This will give you something to compare to if you think something is later amiss.
Colic, as all horse owners know, is a potentially fatal problem, and early intervention can mean the difference between life and death. If you suspect colic, call a vet immediately.
What are you actually listening to? The partly digested food in a horse’s digestive tract will be continually moving through the gut, creating a barrage of rumbling and gurgling sounds.
When the gut is stressed, fluid can often pour into the intestines, which can generate a lot of sloshing noises.
If the horse has diarrhoea, the whole gut operation will be in overdrive and the sound of the moving food can sound like a continuous rumble – almost like a thunderstorm.
The most ominous sound is relative silence. When a twisted bowel or impacted food blocks the progress of intestinal contents, the gut will be much quieter than normal. There may well still be sounds, but they will tend to be intermittent, perhaps every few minutes. There may be occasional tinkling or pinging noises, perhaps like the sound of a water droplet hitting a thin sheet of metal.
These sounds are likely to be gas occasionally bubbling through liquid in the gut. This general absence of sound is potentially very serious; your vet is needed urgently.
How does a vet monitor gut sounds with a stethoscope?
They will listen in four basic quadrants, two on either side of the horse, being above and below the line in the picture at left.
On each side, a vet will normally work their way towards the rear along the top quadrant, and back towards the front on the lower quadrant.
They might typically stop four, even five times, to listen in each quadrant.
Here’s what they’re listening to:
- Upper left quadrant: small intestine.
- Lower left quadrant: large intestine.
- Upper right quadrant: large intestine and caecum.
- Lower right quadrant: large intestine.
The sounds from the small intestine are usually quieter, and not as regular as the symphony pouring from the large intestine. Periods of silence around the small intestine of 10 seconds or so are not unusual.
But be clear: A layman must never place themselves in the position of diagnosing a colic. It is easy to be wrong. For example, noise from one part of the gut may be disguising the ominous silence surrounding an impaction in another part of the gut.
If you have the slightest reason to suspect colic, call a vet.
First published on Horsetalk.co.nz on July 21, 2007