ABSTRACT
Aside from eating, horses spend most of their day resting. In adult horses this occupies about 5-9 hours of a 24-hour day. As the classical flight animals, they rest polyphasically, which means that their resting periods are divided into many short intervals and are distributed throughout the day. In general, horses doze standing; deep sleep in lateral recumbency only occupies a very short portion of the resting time. The duration of sleep per sleeping period averages 20 minutes in an adult horse.
