Wheels

The question of offering wheels or not divides keepers into opponents and proponents. Generally, I count myself among the opponents. Most of my pets have no wheel, because the enclosures are sufficiently large to enable them to move in their natural range of behavior.
If you want offer a wheel, think about whether running is a large part of the natural range of motion or not. It would be useful to lemmings, hamsters and gerbils for example, which rarely or never climb.
On the other hand it would be less useful to acacia rats, mouse-like hamsters or dormice for example. These animals climb a lot and very smart. The wheel would shift the emphasis of their natural motion significantly from climbing to running. That’s why you should avoid wheels for them and prefer to offer more branches and other climbing stuff.

Best wheel a mouse can have

There are many types of wheels. But only few of them are good and healthy for your mice. I consider wooden wheels like on the picture to be especially recommendable, because they fulfil all demands on a secure wheel:

• Unilateral suspension
• Closed tread
• Closed rear
• Completly open front
• Sufficient diameter (prevents mice from bending their back too much)
• Safe material

Never buy such a wheel!

Unfortunately, the majority of pet shops offer unsuitable or really dangerous wheels, since this is unfortunately not prohibited by law.
Unsafe wheels are wheels with the following characteristics:

• Wheels with a tread made of bars
• Wheels with double suspension
• Wheels with the so-called scissors effect
• Too small wheels in which the mice have to bend the spine too much
• Wheels made of soft plastic

The first three points in the paragraph above apply especially for the most common, cheap metal wheels. Unfortunately, the customer doesn’t get any advice of the health consequences of such a wheel when buying it. These include:

• Dislocated and broken limbs
• Bruises and contusions
• Tail or limbs are broken, skeletonised or even demolished
• rachioscoliosis, unilateral degeneration and slipped discs as result of too small wheels

Not to mention the risk with plastic wheels of severe injuries of the gastrointestinal tract by pieces when a mouse chews on the wheel (in the worst case resulting in death). Unfortunately the customer is not told of such risks when buying a wheel. Usually even the shop asistants don’t know about them. Therefore, never rely on the advice you get in a pet shop! The advice is often flawed and may be a serious risk for you pets.

Translation
Angelus Noctis
Proofreading
Jedediah