In Wisconsin, you can use the perch for bait, but they count toward your bag limit.
Example: If you are on a lake with a bag limit of 10, and you are using perch for bait they count toward your daily bag limit.
I wouldn't go overboard, I might use one that was going to die anyway as bait.
I would much rather use a Chubby Darter or Jigging Rap in Perch pattern as my bait.
Check your regs, and good luck.
Wiener