With advances in medical technology, Caesarean sections and inducing births have become somewhat commonplace procedures for assisting human childbirth. But equine delivery is a horse of a different color.
“Horses are a completely different species from all others,” said Dr. Chantal Rothschild, a veterinary medical resident of the equine team at the Washington State University Veterinary Teaching Hospital. “Some parts of the fetal maturation process occur only shortly before and even during birth. When the foal is born without this process completed, severe complications can result, such as respiratory distress, lack of a suckling reflex, gastrointestinal malfunctions and mental retardation.
“A large number of these foals will die, even if they receive intensive care, oxygen support, fluids and have people sitting with them 24 hours a day.”
A recent example seen at the hospital was Gracie the draft horse. She was nearly due with her first foal when she began to display signs of colic, a painful abdominal condition. Mild colic is not uncommon for mares in late pregnancy, but Gracie developed an unusually severe case.
Her owners and doctors considered three alternatives: inducing labor, a Caesarian section or surgery to relieve the colic. They decided on surgery.
While potentially life-saving for a mare, surgery can be life-threatening to her foal because of anesthesia complications. But the alternatives also carried significant risks.
Many foals will not survive a Caesarean delivery, and there are significant complications and costs if they do. “Even if we do it just one day before the foal is ready to arrive naturally, our survival rate is not always encouraging,” Rothschild said. Caesarean deliveries are more appropriate when both the mare and foal likely will die if the procedure is not performed, she said.
Inducing birth also can be a poor decision for horses. “A mare often only engages the foal into the correct birthing position a few hours before delivery,” Rothschild said. “So inducement can cause the fetus to end up backward or sideways when it’s born. This could kill the mare and the foal, or result in severe complications.”
Prince’s fight for survival
The surgery option was selected for Gracie. The fetus was crushing a portion of her intestine, but her doctors were able to repair it. Their next challenge was making sure her abdominal incision would hold together until she was ready to deliver and throughout the birth.
The veterinarians decided to mechanically pull the foal when she started delivery, so she would not have to use her abdominal muscles to push very hard. Gracie made it safely through the birth, but her foal, Prince, was comatose.
The equine team immediately began work to resuscitate him. After 10 minutes, Prince took breaths on his own, but he still had a long way to go.
“He was not responsive. He would not move his head, did not have a suckle response and just laid there,” Rothschild said. “So we had a whole unit made for him with a bed and oxygen, heating pads, blankets. And we had veterinary students sitting with him all night. We also put a feeding tube down his stomach and fed him milk every hour that way for several days.”
Prince’s condition was caused by a complication called hypoxic ischemic encephalopathy, in which there is poor oxygen diffusion into the uterus because the mare is sick or toxic. Though Gracie’s veterinarians anticipated this reaction and put her on oxygen to reduce the effect before she delivered, Prince was still severely affected.
But after two days of care, Prince was able to stand with help for the first time. After two weeks, he also walked on his own, drank from a bucket and eventually nursed on his mother.
“It can take a week or two, but most foals with this condition will regain all their normal abilities,” Rothschild said.“We were so happy to see him make it, but we were also sad when he went home,” she said.
WSU offers intensive care
The WSU equine service provides intensive care for pregnant mares with or at high risk for problems. Ultrasound examinations, 24-hour-a-day monitoring, intensive foal care and emergency Caesarean deliveries are some of the services available. For more information about WSU’s high-risk mare and foal care services, contact the veterinary hospital at 335-0711.