propionic acid

["Cameron Wood" <wood.cameron@acd.net>]

 As long as we're talking hay here, I wonder if any of you could answer a
 question for me.  I'm nearing the end of my hay supply and have been
 looking for more (didn't really intend to keep a third horse for the
 winter, but...o'well  *sigh*).  I found a supplier today with a nice
 selection, priced "okay" for this time of year.  He mentioned that all of
 his hay was treated at baling time with propionic acid, to "keep the hay
 from fermenting" in the mow.  His rationale for this was that he can bale
 the hay sooner than he normally would (reduce drying time), and by doing so
 the hay keeps more of its leaves and he can make tight bales without fear
 of heat-buildup.  I checked out the hay ... it's beautiful first cutting,
 lots of leafy timothy with some alfalfa, and no dust when the bales are
 opened. Looks good.
    My question is.... what is propionic acid, and should I be concerned
 about feeding this to my horses?  The farmer assured me that propionic acid
 is a normal component in a horse's digestive system and there's no problem
 feeding it.  Should I buy it?  Any thoughts? Thanks!
 
 Shannon LVT
 Laingsburg, MI