Ball Python feeding problems

I have a male piebald bp that is around 1400 grams. I got him from a local breeder who rescued him and was bringing his weight back up because his previous owner was mistreating him. I got him in a trade that i did and the guy told me that he was bringing his weight back up cuz the 1st owner only fed him 1 small mouse every few weeks. So he was bringing his weight up and then we traded and now i have been trying to bring his weight up. He will only take very small mice. I have tried to feed him rat pups and small rats but he wont take them. he did try and take a rat one time but he killed it and then after he got to the shoulders of it he spit it back out and never even budged for a rat again. I skipped a feeding because i wanted to see if he would take a rat but he wont even show it attention. the second i throw a mouse in there he attacks it immediately. Is feeding him mice ok? I dont care how much he eats i just want him to eat. Any and all help would be greatly appreciated. Thanks in advance.

http://img.tapatalk.com/d/14/05/23/yqanu7ab.jpg

Here he is with the mouse.he should be taking way bigger then that.

Sent from my LG-D801 using Tapatalk

Feed what he will eat.
Yes mice are okay to feed, I have a couple snakes way over the 1000g mark that have been mousers their whole life.
One of my male pastels just decided to start eating rats on his own.

He looks pretty healthy actually. I'm sure mice are fine for now. Have you tried scenting your rats with mouse scent?


Sent from my iPad using Tapatalk