Further aspects of this are discussed in DogMind page.

A point to remember is that the shoulders and hips of a dog are hinged entirely differently than humans. You'll notice that a biological dog's head rests easily on the floor when lying on its side. For human dogs lying on the side places the head on the top edge of the shoulder, bending the spine -- not good for sleeping. This can cause big problems over time, but there is a simple remedy. Although biological dogs don't use pillows, human dogs to some extent need them.

To a certain degree it is an aesthetic concession in a scene, but if you value your dogs health and ability to perform you'll give him one at bedtime. For those of you who really hate the idea there are alternatives. For example, a soft canvas sack stuffed with old socks, jocks and various other smelly items makes a nice dog pillow.
This will also help him to develop his sense of smell when identifying his Masters socks, boots jocks in some of his doggy games (see DogPlay)

In addition to a pillow, a human dog does need a bed -- at least some of the time. Unfortunately, the structure of the human anatomy is not conducive to sleeping on the side or all curled up on a hard surface.
Over time a human dog can begin to experience cramping, extremely tight muscles atrophy of certain connective structures, and some of the milder forms of arthritis -- not good if you want a healthy pet.
Any kind of large puppy pad, an old blanket folded in the corner, or even an extra large dog bed (available at most chain pet stores) will do nicely. You also might like to let him up on the bed every now and again when he's been exceptionally good.

The dogslave will soon feel right at home in here. Many slaves will settle for this as their prefered sleeping place. Ideally they should be locked in, however there should be arrangements if they need to have a piss in the night.

 

This is not that unusual. The slave (more slave than dog) just loves being with his Master and derives security form his proximity. In this the slave usually sleeps with some form of bondage, it maybe as little as having his collar on with Master holding his leash, maybe in his Chastity shorts, throught to immobilised in a sleep sack, where his Masters is close enought to keep an eye on him.
When sleeping the pup is allowed to sleep in Masters bed in bondage,
with hood on, paws attached to collar usually sitting at below tits
level and ankles restrained.
The leash can be attached to the collar then slides under the cock ring and then held by me around my wrist. Some checking is made to ensure that the leash does not trap skin around the cock ring as neither of you get sleep. The slave needs to know his place and be 'comfortable' there, that is no unnecessary distractions that could take him out of role.

 

When the pup is more developed it will sleep on the floor chained to the bedpost. Still in an applicable  level of bondage, this tends to be the more common (cages are not cheap).
If the slaves sleeps at the side of the bed, the Master need only reach out his hand to touch the dog, stroke it, tickle it.
This tends to be more common when the dog is more a pet.