Newborns -
From birth until the age of 7 weeks old, a pup is considered to be a newborn. During the first few weeks, all that a Chi puppy will do is sleep and drink the dam's milk. There is even very little time devoted to bowel movements, since the dam stimulates the newborn puppy to eliminate. A newborn Chihuahua will slumber anywhere from 20 to 23 hours per day. They will normally only wake up to nurse and this happens roughly every 2 hours.
The prolonged sleeping habits of the Chihuahua puppy
will begin to change noticeable around the 3 week mark. At this time, the pup is learning to walk (it takes about one week for this to be mastered), eyes are fully open and the ability to hear is functional. This is a time of great curiosity and exploration for as a far as the pup can travel from the dam.
Therefore, from week 3 to week 7, a Chihuahua puppy will incrementally stay awake for longer periods of time.
Puppies -
Chihuahua puppies sleep a lot and when they are awake they are often very active and even hyper. It's like 2 sides of a coin; the puppy will snooze so much that owners wonder if the Chi is sleeping too much but then when he wakes up, he has an enormous amount of energy.
From 2 to 6 months old, a Chihuahua puppy may sleep up to 18 hours. From 6 months to the 1 year mark, an hour or two may be slowly deducted from that. The sleeping habits of a Chihuahua puppy will be scattered. He may nod off in the middle of play as he pushes himself to stay awake and enjoy what he is doing until his body simply gives out and he passes out.
The goal for owners, of course, is to try and make the majority of that sleep occur at night when owners wish to be in bed undisturbed and we will go into that ahead.
Adults -
Toy breed dogs such as the Chihuahua that are adults at the age of 1 will sleep roughly 12 to 15 hours. This includes both during the night and naps taken during the daytime. Each dog will vary on how many naps he takes and for how long.
By the 1 year mark, most have learned to snooze the night away and have more control on when they take naps. The young adult Chi is used to his schedule now and knows when to expect walks, feedings, play time and grooming. He can nap in-between those events and usually settles down at night without much prompting.
Dogs left alone for a good portion of the day may nap simply due to boredom while those that are engaged with interaction and activities may stay alert for much longer periods of time.
Seniors -
As a Chi ages there is a gradual slowing down of the body. He will tire out more easily and tends to nap either more frequently or longer. Those that suffer with arthritis and other age related health issues may struggle to find comfort that allows them to fully relax.
You may not notice much of a difference with a 9 or 10 years old Chi, however when the dog enters his teens he will sleep much more than his younger counterpart. Senior Chihuahuas will sleep about 16 to 17 hours unless medical issues or discomfort prevents him from doing so.