Foals have a better chance of surviving dystocia if the mare is taken to an equine hospital as soon as the prolonged delivery is recognized, said Katherine Cole MacGillivray, VMD, Dipl. ACVIM, of Haygard Equine Medical Institute in Lexington, Ky., at the ACVIM Forum 2010 veterinary meeting held in Anaheim, Calif.

Dystocia is usually defined as stage-2 labor (delivery of the foal) that lasts more than 30 minutes. "It is considered an equine emergency. The outcome will have a profound effect on the foal's and mare's survival and the mare's reproductive and overall general health," said MacGillivray.

The causes of dystocia include angular limb deformities of the fetus, fetal size, malpositioning, inadequate uterine contractions, congenital deformities or anomalies, and placental abnormalities