By the way, there is a potentially dangerous illustration circulating on the Internet which suggests giving shots in a very risky area. (See graphic at the right.)

Superimposing an image of the placement of the spine and major blood vessels over that picture shows why that triangle may put you at risk of seriously harming your horse. The bulging muscle in the picture is the brachiocephalic muscle, and the top of the spine runs along, or somewhat above, the upper edge of that muscle. As you can see, depending on the actual build of the horse, the spine may extend well into the triangle, and both the neck artery and the neck vein run right through the middle of it! Even if you miss those blood vessels, you may end up dumping a large amount of a drug in an area where it will be picked up by the blood stream too quickly.

The "triangle" area should only be used by trained folks who are well acquainted with equine anatomy -- not by amateurs. If there's a value to that triangle, it is as a guide to where you can draw blood. The next time your vet takes a blood sample for a Coggins test, watch where he inserts the needle -- right in the triangle! Every vet I've talked to said play it safe when giving shots and stick to that dimple under the mane (the serratus ventralis or trapezius muscles).

This illustration, which is circulating on the Internet, suggests giving shots in a dangerous area.

This triangle may put you at risk of hitting the spine or a major blood vessel!