Perinatal Asphyxia in Foals Perinatal Asphyxia in Foals Perinatal or neonatal asphyxia is a complication that can occur in foals and is related to the birth process. Asphyxia is defined as a decrease in the amount of oxygen supplied to the tissues as a result of a reduction in the amount of oxygen in the blood or the amount of blood flowing to the tissues. Commonly observed CNS signs include jerky movements, spasms, diminished sucking reflex, wandering, blindness, seizures, and coma. Causes of perinatal asphyxia include placental abnormalities, dystocia or delayed delivery, twinning, congenital malformations, and maternal illness.
Treatment involves good nursing to address the multisystemic nature of the condition.
Histories sometimes indicated that the placental membranes were improperly delivered or visualized before the foal was observed. In most cases the foal was dead on delivery, however, some were born alive but had weak vital signs and died. Typical findings at necropsy included partially aerated lungs, bleeding in the respiratory tract and on the heart, oedema in the mesentery and mesenteric lymph nodes, and bleeding into the shoulder joints with reddish staining of the articular cartilage. The bleeding is the result of excessive squeezing of the foal as it passes through the birth canal suggesting a difficult or delayed delivery. The fact that the placenta is passed so quickly after delivery indicates it must begin detaching from the uterus during or soon after delivery.