What is Hyperactivity?
Unruly, fizzy, unsafe behaviour is more of an issue in equestrian/pleasure horses than it is in racing horses, though feeding for good behaviour is important in young racehorses. Changes in behaviour can be caused by:
Feeding too much for the work being done.
Feeding unsuitable feeds.
Vitamin and mineral deficiencies, notably vitamin B1 and magnesium.
What does the horse need.
In some cases, horses that are hyperactive on grain based feeds will settle down on high fibre/high fat feeds.