I agree with newchickowner- the hay and grasses in Florida are horrible as far as nutitional value. Also, just a thought, have you check both of them for sand? If they were polo ponies, they might have spent time in So Florida and have bellies full of sand. When I was there we had to bran mash at least once a week and added metamucil to every feeding.
Testing is easy, though not necessarily the most pleasant thing to do. Take a ziplock bag and wait for a fresh poop. Scoop a ball in the bag and add water. Seal and shake then hold it by on corner so you have one corner pointing down. If they have sand in the intestine, it will all settle in the bottom corner of the bag.
Just a thought..................
Testing is easy, though not necessarily the most pleasant thing to do. Take a ziplock bag and wait for a fresh poop. Scoop a ball in the bag and add water. Seal and shake then hold it by on corner so you have one corner pointing down. If they have sand in the intestine, it will all settle in the bottom corner of the bag.
Just a thought..................