Not good at critiquing conformation, but there's no way she weighs 1000lbs. And as Tasia said, consider a calorie booster instead of grain...especially if she's prone to colic. Free choice hay/pasture will also go a long way. Through our -30 winter I packed on over 100lbs onto my Clyde cross mare using Cool Command. Oats and sweet feed would've rendered her useless as a riding horse due to energy alone!