Quote Originally Posted by bcr229 View Post
Did you look at the FDA withdrawal times for slaughtering larger critters treated with Ivomec? I only glanced at a few, but noted one listed at 35 days.

Personally, I would look at the max time given and feed the rats to my critters no sooner than that. Rodents probably have higher metabolisms than food animals anyway so there shouldn't be much ivermectin left if you wait for that duration.
I looked and could not find anything, other than do not use on horses intended for human consumption.