Feeding question with a "twist"

[h20hunter]

Our BP, Snickers is a full grown, healthy female (I was told) adult (7years old) normal. Husbandry is good with even temps, basking areas, water, security, no worries. She has only been with us for a year plus a bit and has about doubled in size with proper feedings. She is currently on meduim f/t rats and for the most part was eating like a champ every week to 10 days. She has refused food that last few attempts with apprently no ill affects. He size is good, weight is good, temprament is good, shed is good. My thinking is she is just being her usual BP self. I have one more rat that is thawing as we speak (last attempt to feed was a last week) and will offer it to her tonight. If she eats, great, if not, I'm not yet concerned.

Now, to my question. My local pet store sells f/t as well as live feeders. They are not sold as pets and fed on the hush hush. They are sold as feeders. My thinking, to save a few bucks and to not waste the rat is to buy live, kill, and offer. If she eats great, if not I can now freeze and offer at a later date. My question revolves around the best way those with experience believe it is the most humane to dispatch the rat.

Option 1. Cervical dislocation. I have reviewed how to do this and feel I can accomplish the task quickly.
Option 2. Dry Ice asphyixiation. I have a local store that carries it, could store it in my deep freeze, and understand how the process works.
Option 3. Brain spike. I have various instruments that could be used to quickly spike the brain resulting in a quick death.

As a hunter I have killed, cleaned, butchered, and eaten game animals. I would not say I "enjoy" the process of taking the life but have respect for it and do my utmost to bring the animals I've killed to the fastest end possible. Even though they are little old rats I still believe in being humane.

So, that being said, I'd like to hear opinions and suggestions on feeding freshly killed as well as those that have experience in pre-killing their snakes prey.

Also, I have no problems with those that feed live but since ours isn't on live, and has never needed to be, I see no reason to consider that as an option until way down the line when the health of the snake may be in question.