I don't use it either, you know the old saying once bitten twice shy. Just I've read more convincing articles and post about shakelys both in the sheep mags and cattlemans magazines. Wish I had a reference for ya, but my book marks are a mess in places. I'm prefectly happy with the fenbendazole, Ivermectins, and Tramisol, so I don't have a great motivation to change. I'm only very rarely asked for organic meat at the market.