Anyone know the approximate time line of long it takes a wormer to work it's way through a horse's system ? I'm thinking in terms of if I keep a horse shut in a yard while the wormer does it's thing, how long till the majority of the manure containing any worms comes through ? Also, I've always throught it best to worm at feed time as I (think) I read somewhere that wormers work best if digested from a full stomach :confused: I tend to worm my horse an hour or 2 after her hard feed (just before I give her her hay). I never worm on an empty stomach. Is there an optimum time ?