Color blindness, also known as color vision deficiency, is the decreased ability to see 
Do you know what colors are most commonly hard to see with the color blindness illness?
Color blindness
Color blindness, also known as color vision deficiency, is the decreased ability to see color or differences in color. Simple tasks such as selecting ripe fruit, choosing clothing, and reading traffic lights can be more challenging. Color blindness may also make some educational activities more difficult. However, problems are generally minor, and most people find that they can adapt. People with total color blindness (achromatopsia) may also have decreased visual acuity and be uncomfortable in bright environments.
The most common cause of color
vision.
Visual capacity of the horse Color vision.
Horses are not color blind, they have two-color, or dichromatic vision. This means they distinguish colors in two wavelength regions of visible light, compared to the three-color (trichromic vision) of most humans. In other words, horses naturally see the blue and green colors of the spectrum and the color variations based upon them, but cannot distinguish red. Research indicates that their color vision is somewhat like red-green color blindness in humans,