There are a few areas on the body that provide important information regarding the state of a horse's circulatory health. These areas include the gums, the pink membrane inside the nostrils, the whites of the eyes, and the pink inner vulvar membranes of mares. That said, the simple act of evaluating the color of your horse's gums is a very important skill.

Pale mucous membranes are seen in horses that are anemic (low red blood cell count), in pain, or in shock. A pale color can also be confused with normal, because some horses have more pale appearing gums than others. Always compare the appearance to the opposite side of the mouth, and to the color of the gums in other healthy horses. Consider the light quality, as that can change the appearance of the gums significantly.