I think 30 days in the electric chair would be more apropos for anyone who does things of this nature. They have a sick mind and are reminiscent of the Count Marquis deSade. If memory serves me correctly, I believe this is how Jeffrey Dohmer started off...torturing and dismembering animals and we all know what he did and ended up. Back in the Middle and Dark Ages they use to put "heretics" on a device known as a rack where their limbs were tied and stretched. Perhaps a few days on the rack would help these guys to see what pain is all about.
No excuse for this and they deserve the maximum sentence possible. There's nothing more innocent (save a newborn baby) than a little puppy and may God render unto these guys due recompense for their deeds.