Oh man I love me some TD games :D
It's a great take on theme and really fun. I did run into a bug, where chickens would disappear when I clicked in the middle of the screen. I think that the "Sell" button was still active oddly enough.
The graphics are funny and cartoony and the sounds are a good fit. It has a bit of Mid-00's Newgrounds flashgame feel. Great job :)