magnesium supplements for tying up

[Suzanne Mounts <mountss@usfca.edu>]

The most recent Horse Journal has an article on magnesium supplements (Tie
Free, Untie, Magnesium 3000, E-Se-Mag Concentrate) for horses that are
prone to tying-up.  The article suggests the supplements were helpful, but
the field testing seems to have involved a small number of horses.  Any
experience, successful or otherwise, with using these specific products or
with magnesium supplements generally for managing horses that tie up?

Suzanne Mounts