When deciding on a new horse, a key factor is its health. Although one cannot be 100% certain that a horse is absolutely healthy, there are some basic checks.
The first indication is the overall appearance. The coat should be shinny and even. The body should be well proportioned with well toned muscle, neither over weight or under weight. It should stand evenly an all four feet, with the weight evenly distributed and the hooves pointing straightforward. Although it may rest a hind leg (but not a front one), it should not do so for long periods or always the same leg.
The legs should be free from swellings, bumps or hot spots. Slowly run your hands over the entire length of the legs, with special attention to the lower parts. The outside of the hooves should be smooth, even and free of cracks.
Lift a hoof and check the sole for correct shape and any indications of previous injury; then repeat with the other three hooves. The angle and tilt of all four hooves should be correct and identical. If the horse is reluctant to lift a foot, it could just be lack of training, but may well be that it does not want to put more weight on another hoof, which would indicate an injury (to hoof, leg or spine). If you are unsure on any of these points, ask a professional farrier or blacksmith to perform the examination.
Check the gums. They should be pink, shiny and moist. If they are dry, tacky, pale or any color other than salmon pink, there is a health issue. If one presses gently on the gums (careful with your fingers!), at the point where you are pressing they will turn white but as soon as you remove your finger the color should completely return to pink within two seconds.
Check the teeth (you may want to use the services of a horse dentist) for spurs, unevenness or excessive wear. Try feeding the horse hay and watch how it eats. It should use both sides of its jaw equally and eat steadily. Dropping hay or leaving hay partly chewed indicates a problem either with the teeth or the jaw joints.
Check the droppings of the horse. They should not be loose or sloppy (not like a cow's). The odor should be mild and inoffensive. The color will depend on the diet. If a horse is under nervous stress (e.g. during transport) it is normal for the droppings to become more liquid but this should correct itself as soon as the horse is returned to normal conditions.
The horse should look happy, alert and interested in what is happening. Its ears should stand up and should move alertly in response to sounds. It should be interested in what is happening around it, but not nervous.
Have the horse taken to an exercise ring and exercised at all gaits (e.g. walk, trot, and gallop). It should take easy, smooth strides of equal length and with the weight evenly spread on all four legs. It should not favor any leg. Circle the horse in both directions (left inside and right inside) to make sure that it performs equally well in both directions.
It should not sweat (except during hot weather) until it has been worked for some time at speed. Its respiration should gradually increase as the gait picks up but it should not breathe hard except at a fast gait. As the gait is reduced, its respiration should quickly reduce. Once the horse stops, its breathing and pulse should quickly return to resting normal. Neither during nor after exercise should the horse shown any sign of discomfort, pain or limping.
Discuss the horse's medical history with the owner and seller. Ask to see its inoculation book and medical records. Check if you can discuss these with the horse's regular veterinarian. In particular, check if the horse has ever had any illness, especially colic or laminitis. Any incomplete or evasive answers should be a concern. Ask what the horse's diet is, since horses fed a natural diet (grass, supplemented by hay) are less likely to develop digestive problems than horses fed mainly on grains or feeds. Finally, check if the seller will provide a written guarantee for any existing health issues which you discover following the purchase.
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