Use whatever equine specific milk replacer that is readily available that the foal will drink. Follow the directions on the bag for quantity. Clean the bucket with hot soapy water and rinse well EVERY single time before refilling.
In the beginning hold the bucket for the foal and then hang the bucket on the fence/wall until the next feeding. The foal will paw at the bucket while drinking. We double the dosage at first so it’s deep enough to get its mouth into it, tossing the extra before refilling. (Actually the dogs get it.) Once the foal learns, go back to the recommended dosage. Until the foal is about two weeks old, remove all access to water.
Do NOT turn the foal into a puppy. Do NOT over feed. Do NOT underfeed. Do NOT ignore diarrhea, loss of appetite, or lameness. Do NOT leave a halter on.