Why is feeding horses the hardest thing I do? In the research center, if I am home, I feed all the horses at least twice a day by myself. Rule of thumb is to feed a horse 2% of their body weight daily at rest. Problems arise in; what does your horse weigh, is your hay alfalfa or grass hay, is the hay fresh cut or last years hay, what is the temperature outside, do they have shelter or blankets, is your horse an easy keeper and last but not least how much exercise do they get. Perfect weight for a horse is in the eye of the beholder.
The only thing l have learned is to watch my horses every day to see if they are over weight or under weight and adjust the amount of hay.
I always start by feeding each horse 2% of there body weight and adjust from there by increasing of decreasing 2 lbs per day.
How much is 20 lbs of hay per day for a 1000 lb horse? Best way is to weigh a bale and decide how long it should last.
Remember horses get thin fast and put weight on slowly.