The trick is, when a horse is young fill a plain plastic syringe with apple sauce and act as if you are worming them, do it every day, and when worming comes they'll think they are getting apple sauce. lol. Then after worming continue to do so for a few days.
Every time you worm, do the apple sauce thing for 2 or 3 days prior, that way when you worm, once again they think they're getting apple sauce.

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