Are sheep and goat sensitive to light color?
The eyes of the goat and sheep are similar to a human’s eyes, with a lens, cornea, iris and retina. A key difference though, is that the retina is shaped like a rectangle. This offers these ungulates massive peripheral vision, a nearly-whole area of 320-340 degrees!
However, this feature tends to reduce the animal's ability to perceive depth as well as its view angle to that of only 20-60 degrees. Then you may imagine whether sheep and goat are sensitive to light color?
Goats are Dichromats, they have two cone Opsin proteins, a Short Wavelength Sensitive Cone (SWS or S-cone) that has a maximum vision at 444-455 nm(bright purple). The second Opsin protein is Long Wavelength Sensitive Cones (LWS or L-cone) which has a maximum vision at 553nm (Yellowish-green).
Like other dichromats, they use the relative strength of the two signals to ascribe a 'color' to the signal. This can be calculated mathematically using the log of the absorbance at a particular wavelength. Sheep can see a various colors including Violet, Blue, Cyan, Green, Yellow, Orange and a slight bit of Red. The wavelength of the red color is 620-750nm while sheep can see up to 650nm.
Despite the wavelength for red being visible to sheep, they are unable to interpret the color as Red, due to being dichromatic (Red-green colorblindness). This has implications to their interpretation of yellow and orange as well since yellow and orange are visualized by the combination of red and green receptive cones.
Because the sheep lacks the L-Cones, which is necessary to translate the designated wavelengths to “red”, we can’t expect the ungulates to interpret the wavelengths for yellow, orange or red differently than we do.
Thus Sheep and Goats are certainly able to see purples, blues, and greens very well, but other colors like red (as we see them) are not sensitive to them.
In this way, you can do a lot of things to take care of your sheep and goats in your farm. Think about at night, you are going to check if there is anything abnormality like predators, or attackers, or the animals loss caused by them, or check whether their babies have the healthy breaths. The red light flashlight meet your needs in the whole processes and all of these actions can’t generate much light pollution which affects their livings at night.