Round-the-clock care helps thoroughbred give birth to rambunctious colt

Attending to the needs of a pregnant mare with medical complications does not fit into regular veterinary office hours.

As foaling became imminent for an 18-year-old thoroughbred named Miss Ocean City, clinicians Megan Marchitello and Krista Estell stayed for several nights at the Marion duPont Scott Equine Medical Center (EMC) in Leesburg to ensure they would be present for the birth.  

Their attentive care and that of other staff before, during, and after foaling was rewarded with the successful birth and development of a handsome colt after Miss Ocean City was deemed a “high-risk” mare having suffered complications in prior pregnancies.

“Miss Ocean City gave us an exceptional colt who is delightful and full of personality," said Ann Backer, the horses’ owner. “Many thanks to EMC staff for three weeks of around-the-clock care given to this mare who has always had difficulty foaling.”  

Backer is a longtime supporter of the equine medical center, and is a thoughtful, strategic donor, focusing on specific areas that provide the most impact for all our equine patients. The equine medical center is one of three teaching hospitals and animal care facilities of the Virginia-Maryland College of Veterinary Medicine.

Miss Ocean City was taken to the center in late January, when she was 319 days into her pregnancy. The typical gestation duration for a horse is about 340 days, or 11 months. 

At her home in The Plains, Virginia, on about day 150 of her pregnancy, Miss Ocean City was diagnosed with placental edema by referring veterinarian Christine Dainis-Adams. Placental edema is an accumulation of fluid and inflammation within the placenta that can affect the flow of nutrients and oxygen to the unborn foal and potentially lead to pregnancy loss or complications at birth.

When Miss Ocean City arrived at the equine medical center for monitoring, Marchitello, clinical instructor of equine medicine, fitted the mare with a foal alert device and placed her in a video-monitored, well-padded stall. Mare watch volunteers kept an around the clock watch on her progress.  

Eighteen days after the mare’s arrival, routine testing revealed a positive anti-Ua antibody, which indicates a risk for her foal developing neonatal isoerythrolysis. When a mare has this condition, the first milk, or colostrum, can be toxic to the foal. This can occur when a foal inherits the same blood type as its father. Pre-screened colostrum was sourced from Kentucky to be used for the foal after birth. 

Several days later, Miss Ocean City was restless and started to lose milk. Sensing that foaling was imminent, Marchitello and Estell, clinical associate professor of equine medicine, began staying at the hospital overnight. 

On Feb. 21, just over a month after having arrived at the equine medical center, Miss Ocean City gave birth in the early morning to a beautiful dark bay colt. The foal was lively and bright, his vitals were normal, and he bonded well with his mom. 

Because of Miss Ocean City’s neonatal isoerythrolysis, the colt was fed the pre-screened colostrum through a feeding tube and he was also given plasma infusions and antibiotics. 

After a tense two hours, the colt was standing confidently. The next day testing determined he could safely nurse from Miss Ocean City, but additional testing of the colt showed partial failure of passive transfer, so he was given more plasma. This condition occurs in foals that do not receive adequate amounts of maternal antibodies from the colostrum during the first 24 hours of life. This results in the foal having insufficient immunity to fight off infections making it more susceptible to disease. 

Over several more days of continuous, 24-hour care, the colt's antibody levels stabilized. Close attention was given to monitoring his immune status as he was gradually switched to oral antibiotics, preparing him for discharge.

Five days after giving birth of her colt foal, Miss Ocean City was able to leave the hospital with her colt by her side.