Dummy foals are also called neonatal encephalopathy and perinatal asphyxia syndrome. Dr. Pam Wilkins indicates in the Practitioner that there is a wide spectrum of clinical signs associated with dummy foal syndrome, including mild depression with loss of the suckle reflex, ranging up to severe signs including grand mal seizures. Most of these foals are normal at birth but usually start showing signs of nervous system disease within the first 24 hours. These foals can have abnormalities of other systems including gastrointestinal, kidneys, cardiovascular, respiratory and even endocrine systems.
The cause of the syndrome is believed to be related to difficult birth or premature separation of the placenta at foaling, but some foals may have an unexplained decrease in oxygen even before foaling. These foals are quite difficult to treat on the farm and most of them really need to be in a hospital intensive care stall. Controlling seizures is critical as is supporting circulation and correcting metabolic abnormalities, and most of these therapies involve close monitoring of blood work and continual intravenous treatment. Some of these foals can develop fluid buildup (edema) in the brain, and treatment for that consists of medication to decrease brain swelling to avoid further damage. Some foals will require blood transfusions and for them fluid support is critical but you must be careful as giving too many fluids can lead to other problems. Some foals will require tube feeding or even intravenous feeding as without nutrition, many of these foals will become weak. If you have a foal that has any nervous system signs, the foal may be a dummy foal and most of those require immediate intensive care to survive.