Dogs do not have fixed sleep times and can sleep anytime during the 24 hours of the day, sleeping whenever they have the chance. But more concentrated sleep times are usually before noon and around 2 to 3 a.m. The length of daily sleep varies.
Dogs like to hide their mouths under their two forelimbs when sleeping because their noses have the most sensitive sense of smell and need protection. At the same time, this position ensures the nose is always alert to the surroundings to react at any time.
Older and young dogs sleep longer, while strong and young dogs sleep less. Dogs generally stay in a light sleep state and can wake up at slight movements, but there are also times of deep sleep. After deep sleep, dogs are not easily awakened and sometimes utter dreamspeak, like light barking or moaning, accompanied by limb twitches and slight movements of the head and ears. In light sleep, dogs lie in a prone position, with their head between the two front paws, often with one ear close to the ground.
When fully asleep, they often lie on their side with their whole body stretched out, appearing very comfortable.
Dogs do not easily get awakened by familiar people or their owners when sleeping, but they remain sensitive to unfamiliar sounds. When suddenly awakened, dogs often feel very upset and show displeasure towards whoever woke them. A dog just awakened may have blurry eyes and might not even recognize the owner, so sometimes the dog’s displeasure is vented on the owner by barking in discontent.
If dogs do not get enough sleep, their working ability decreases significantly, and they make many mistakes. Likewise, insufficient sleep can also worsen a dog's mood. A dog lacking sleep will lie down whenever possible, be unwilling to stand, yawn frequently, have dull eyes, and appear distracted.
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