Boredom

Ad lib hay and lots of small feeds - just a few carrots and chaff.

I also put in toys - lickits etc, hung swedes, hid carrots in the haynets and floated apples in water when I had my mare on box rest.

She spent the time eating away on lots of hay and low cal feeds and licking her treats.

She was fed 6 times a day with tiny feeds and skipped out at the same time so she had lots of visits.

People though she was doped, but she was just kept eating which luckily for me she likes to do.
 
grass haynets are good, and haynets inside haynets to make it harder for them to eat the food.
or one of those ball things they have to push around to get food out - not hard feed obviously of on box rest but you could put carrots in there.
having hay in different places around the box so they move around to eat.
maybe put her in a box with a big window or different view?
 
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