From Normal Delivery to Dystocia: Knowing When to Refer the Mare

Parturition is a very rapid process in the mare, and most foalings are normal. However, when dystocia occurs, it can rapidly become a critical situation for the life of the foal and potentially the mare. It is therefore extremely important to closely monitor each foaling. However, this can be challenging because most mares foal during the nighttime hours. Because day of parturition cannot be accurately predicted based solely on ovulation or breeding dates, several tools, including physical signs, mammary secretions, and monitoring systems, can be used to predict when a mare is likely to foal. The normal foaling process consists of three stages. Stage 1 involves rotation of the fetus from a dorsopubic to a dorsosacral position. Stage 2 begins with rupture of the chorioallantois and ends with delivery of the foal. Stage 3 consists of expulsion of the fetal membranes. The most common causes of dystocia in the mares are abnormal fetal presentation, position and posture, whereas fetomaternal disproportion is relatively uncommon. Many cases of dystocia can be corrected at the farm with simple manipulation. Others should be referred promptly because they are extremely difficult to correct manually and may require a cesarean section when the fetus is alive.

• Describe the signs of approaching parturition.
• Describe the normal progression of equine parturition.
• Describe fetal maldispositions using appropriate veterinary terminology.
• Describe the appropriate clinical management plan for different types of dystocia and identify when referral is indicated.