One of my mares, every evening after a full day's work harrowing, stands
for an hour or so with her head to the ground, shaking it frequently and
not touching the feed till the spell was over. She does not seem to be
any worse off, and in the morning seems to be in good shape.
This is due to a mold or fungus in the earth or hay. Let them have
access to plenty of water during the day. In the morning feed give a
handful of sodium hyposulphate.
Next: Treatment For Horse's Feet