Declawing cats

31% of cat owners in the US declaw their pet. Declawing is the cruel practice of removing the cat's claws, a process equivalent to removing the top portion of your fingers. The cat loses the ability to grab items, scratch themselves, etc. The process leaves the cat vulnerable to infection in the short term, and can have long lasting effects on the animals mental and physical health. Imagine walking without half of your toes; the experience would be a lot more painful and difficult. Declawed cats experience back and spine issues later in life that will be unpleasant for the cat and possibly costly for the owner.

Many people see declawing their cats as a way to protect their health and furniture. No claws means no scratches, right? Unfortunately declawing cats can make them more aggressive and more prone to bite. Claws are a cats first defense, taking that away from them forces the animal to be in a constant state of feeling unarmed and vulnerable. It is far more likely that you will get an infection from a cat's bite than a scratch, and declawed cats will likely bite more. Train your cat to use a scratching post instead of a procedure that compromises the cat's well being in favor of a couch.

http://www.humanesociety.org/animals/cats/tips/declawing.html
http://www.paw-rescue.org/declaw_paper.php