A very cute but fun platformer. I like how the characters are silhouettes (it is fun trying to make out what the other animals you're rescuing are), but the backgrounds are detailed. The levels are quite well designed, as are the sound effects. I also like the music; very interesting contrast of high and low notes, along with the percussion really gives it that old-school GameBoy feel.
Some of the hitboxes for the cat seemed a bit odd; I was able to touch one of the saws on the edge and not get hurt. Well, I guess it wasn't a huge issue, since it's good not to lose health, though it might be better if it was more consistent to where your character is.
I really like how the respawn system allows you to start over the same level with the animals you've already rescued. However, upon respawning, I will echo what Sean said on the ratings page and mention that the Rescued counter disappears, leaving only a Health bar in the HUD.
Also, I enjoyed the wall jumping; at times, it seems like the cat simply bounces off the walls with its front paws and that looks cool. I take it that you can also bounce off of thin platforms and even moving platforms if you're precise enough. Because of this, it is quite easy to land on a platform with just the cat's head, making it look like the cat is stuck inside the moving platform. I'm guessing this is to allow for the player to actually wall jump off that moving platform. It definitely does look a little odd, not to mention platforms don't typically have walls associated on them.
Lastly, palette changes are a wonderful thing. All in all, a great jam game.