Adopting a pet is a big responsibility, and it will often change the life of the person adopting the pet. It will also, however, absolutely change the life of the pet being adopted as well. These pictures will show you how much difference a single day can make in the life of a pet that has finally been adopted.

It may take a while for some of these pets to get back to proper nutrition, but the change in many of them is psychological, not physical. The look that appears on their face once they've realized that they're going to live in a new forever home is one that probably hasn't crossed their face in a very long time.

Needless to say, if you're thinking about getting a pet, please consider the pros and cons of adoption, too! But if you've already got a cute before-and-after adoptee, we'd love to see their shining face in this post!

(h/t: buzzfeed)