Cows do not sleep with their eyes open, although it may sometimes appear that way. Like many animals, cows have specific sleeping patterns, and they typically close their eyes while they are sleeping.
However, cows have a unique way of resting that can be misleading. They often enter a light sleep state while standing up, which allows them to be somewhat alert to potential dangers in their environment. During this time, their eyes may appear open or half-open, but they are not in deep sleep. When cows go into deeper sleep, they usually lie down and fully close their eyes.
Thus, while it may look like cows are sleeping with their eyes open, they are merely taking a light rest while remaining vigilant. It’s an adaptation that helps them stay safe from predators.