Bk from Avon Lake writes
There are some instances when rodents can be resistant to a certain active ingredient in a bait and there may be instances where the rodents will avoid the bait all together (bait is old or spoiled, too many alternate food sources are available). We recommend changing to a bait with a different active ingredient so that you will have fresh bait and you can avoid any issues with resistance.
Answer last updated on: 08/24/2013