When a horse lies down, it might:
* Snort or blow air out of their nostrils: This could be a way of relaxing or letting out a sigh.
* Make a soft whinny or a low rumble: This could indicate contentment or simply a change in breathing pattern.
However, it's important to remember that a horse lying down could also mean they are:
* Tired: This is the most common reason.
* Sick or injured: It's important to observe the horse's overall demeanor and see if there are any other signs of discomfort.
So, while a horse doesn't literally "say" anything when they lie down, they might make a sound or show certain body language that hints at their mood or intentions.