Bite the bullet and buy new, metal trash cans to store your feed. The first year I kept horses (1985), I bought new, plastic trash cans with lids--they were heavy plastic, too--and it took a couple of weeks before mice destroyed the lid on one. I still have the trash can, in my garage, for trash, sans the lid. I am STILL using old, metal trash cans in my grain room--horses and chickens in my new 5 acre back yard--and some are over 25yo.
I also have a big oil drum that was left by the previous owner. I can keep 250 pounds of feed in that in my grain room, and it currently has layer pellets in it.
ALWAYS store in metal and ALWAYS put the lids on.
Mice are destructive and carry diseases and if you keep your food in or near your house-- I DON'T!!! --mice will get into YOUR food after they work on your animal feed. Btw, I own 5 cats, who come and go from the house.