Hey so here is the deal.

I have a one and a half year old Dumerils boa (about 3 and half feet long). Currently he only will eat live mice. My biggest concern is that he is growing at a steady rate and now eating jumbo mice, but as he grows I don't want to have to feed him multiple mice at a time and would rather have him eating rats. Once I am able to switch to rats, I plan to transfer to F/T. However, my Dumerils is terrified of any rat, no matter the size.

Whether it is a rat pinky, pup, anything, he immediately tenses up and rears up on the side of his enclosure as soon as the rat is placed inside. At most, if the rat gets anywhere near him he will strike at it defensively but will retreat away. Now, I have had this guy since he was born and know for a fact that he has never had a bad experience with a rat or anything where he was bit, so I cant see why is is so afraid. But for some reason he is terrified of them. With live mice, he is super aggressive. As soon as they are in the enclosure he seeks them out and grabs them right away. He doesn't wait to ambush.

To try and switch him over to rats, I have already tried the following (most of these have been attempted multiple times):

- Scented a rat pup with a live mouse (both leaving them in a bag together for over an hour and literally rubbing the mouse all over the rat pup)
- Placed a rat pup in dirty mouse bedding for an hour
- Waited a month between feedings, and then presented with a rat pup (also scented with a mouse).
- Freshly killed rat pup
- Brained F/T rat pups
- F/T rat pup with mouse brain on them
- Placed him in small tub with F/T rat overnight.
- Placed a live mouse in enclosure and then tried to switch out a rat after he showed interest.
- Gave him a small live mouse and then introduced a small live rat right after.

Using all of these methods, the best reaction I ever get is a few times he will get closer to the rat. But as soon as he is within a few inches he flicks his tongue and then either shows no interest or backs up defensively again.

This has obviously been an ongoing thing, but I try to space attempts out because he seems to get so stressed when he smells a rat.

Any ideas would be appreciated. Has anyone else had a similar issue?