No. We are not casting aspersions on your new baby's intelligence. The term Dummy Foal is applied to newborn foals that just do not seem to have the natural instinct to nurse.
Most often, this is a developmental condition that is temporary and of short duration. But it does need to be addressed.
Neonatal Maladjustment Syndrome is the more professional term for this condition. While there can be any number of reasons for a newborn to behave in this abnormal way, the most common cause is a lack of oxygen prior to birth. The umbilical cord may have ruptured prematurely. Another cause might be a foal's low glucose levels; or dystocia or septicemia might be a factor.
A foal who wanders aimlessly around the stall instead of attempting to nurse; or who seems irritable or disoriented is exhibiting only mild symptoms. More severe symptoms can include seizures and may even lead to coma and death. DO NOT wait for this condition to get better on its own. Call your veterinarian for immediate treatment if you even suspect that your foal has this condition.
Your veterinarian may administer glucose, oxygen or intravenous fluids; and give instructions as to the best way to encourage the foal to nurse from mama or accept a bottle.
Although off to a rocky start, if the condition is properly treated in its early stages, most foals with this syndrome will develop normally. There will be nothing in your horse's personality or performance as a mature adult to indicate this syndrome ever existed.