-_-"
I know I keep frozen worms and what not in my freezer but I will
say no to a rat as well. Nevermind that you wrap it up in layers of
plastic bag but no rats in the freezer!!!!!
Alternatively, feed the rat to someone with an alligator gar or
snapping turtle...at least it's part of the food chain
I keep my frozen brine shrimps in their blister pack inside a
Ziploc bag in a compartment in my freezer too.
But stuffing a dirty sewer rat into the freezer alongside the
frozen food that we will eventually consume... that is
unhygienic!! 
Fatum, think of it this way, if you knew that your favourite
restaurant freezes rats in their freezer, will you still patronise
the restaurant?! 