Nurse Mares: Four-Legged Mary Poppins to the Rescue
When veterinarians discovered a bacterial infection following exploratory abdominal surgery on champion race mare Rachel Alexandra, her 2013 Bernardini filly was immediately transferred to a nurse mare.
Although they aren't well-publicized players in the breeding industry, nurse mares are much-appreciated surrogates in a variety of situations. Most commonly they are brought in by Thoroughbred breeders when a foal is born to a mare who dies or experiences major health issues that render her unable to care for a foal. The latter was the case with Rachel Alexandra, who returned home to Stonestreet Farm Tuesday after several weeks at Rood & Riddle Equine Hospital. Nurse mares may also be called in if a broodmare rejects her foal or if she has difficulty producing milk.
WinStar Farm general manager Chris Baker said that for mares in the latter category, managers employ hormonal therapies such as domperidone or oxytocin (both of which are used in women) to encourage milk production or letdown in mares before bringing a surrogate into the mix.
“Nobody takes the decision of putting a foal on a nurse mare lightly,” he said. “A foal is best raised by its own mother. You're going to make efforts to get the mare to produce milk if that's the issue.”
A nurse mare may be requested if a broodmare is shipping out of the country to be bred and the foal is too small to make the journey, although such cases are relatively rare. Nurse mares are not brought in for the one to three hours in which a broodmare is sent away from the farm to be bred back, Baker said.
“There's a bonding process that has to take place that's not something you can do temporarily,” he said. “You're not going to try to do it temporarily; it's kind of like flipping a switch. When you go with that, you stay with it for the safety of the mare and foal.”
Some larger farms keep their own band of nurse mares, while others lease nurse mares as needed. Bill Roseberry, who manages Roseberry's Nurse Mares in Central Kentucky, said he gets calls throughout the foaling season, although this year seems especially busy. He's already sent 26 mares out to help struggling foals and has received an additional 60 or 70 calls requesting his mares. Roseberry keeps close to 100 mares on his farm, many of whom are Quarter Horses and Tennessee Walkers.
While there is concern about mistreatment to nurse mares or their foals, Baker and Roseberry said that nurse mare facilities operate like any other aspect of the equine world—some may mistreat their horses, but “the majority” strive to find nurse mare foals good homes.
“I would like to get people to understand that we have been doing this for over 30 years, and we have yet to kill a foal for any reason unless it had some sort of physical problem that can't be fixed,” Roseberry said. “If I had to ‘dispose' of foals like that, I'd be out of the business. I feel very strongly about that.”
“Responsible nurse mare owners love those foals like their own,” echoed Baker, who said in his experience, mistreatment of nurse mare foals is not the norm. “There are people who are feeding their horses before they're feeding themselves.”
When a nurse mare is sent out to care for a new foal, the introduction process is slow and steady. She is often outfitted with restraints such as a blindfold and/or hobbles to allow her to move and gradually acclimate to the new baby while preventing her from kicking or biting the foal in surprise if the meeting doesn't go well. Managers may also employ a mild tranquilizer or Vicks VapoRub to keep the mare calm and reduce the number of overwhelming scents that might put her on edge. The acclimation takes between 12 and 24 hours and is carefully monitored by farm personnel who gradually remove the blindfold or hobbles. After the bonding period is over, nurse mare and baby are considered a pair and remain together until the foal would normally be weaned. Once a foal is attached to a nurse mare, it will not be reunited with its dam, since it likely would not recognize her.
Baker and Roseberry said that experienced nurse mares handle the transition well and need minimal management, and young foals don't act stressed or depressed by the change. Older foals who have developed recognition of their dams are slower to transition, Baker said, but usually settle in with some extra attention when they get hungry.
As adults, WinStar's Baker said he doesn't often see any lasting effects of a horse's upbringing by a nurse mare as opposed to its biological parent. In cases where a foal was bottle-raised for a period of time before transitioning to a surrogate, however, he said adults tend to be more people-oriented than average.
Nurse mares are often bred back to teaser stallions on the breeding farm during their lease, and Roseberry said he prefers they be sent to stallions “with some color” to make the nurse mare foal more marketable as a riding horse.
Although milk production can be enhanced by hormones, a mare must have a foal each year to continue lactation. Roseberry said that on his farm, which has been in operation 32 years, his family raises nurse mare foals until they are old enough for sale.
Roseberry said he ensures nurse mare foals receive the antibody and nutrient-rich colostrum from their dams in the first hours after birth, and he does not separate them until he is sure the foal's immune system is off to a good start. Foals are allowed to nurse until the mare is needed, at which point the process is similar to the weaning that all horses go through. Nurse mare foals are raised together and appear content to drink from a bottle or bucket.
“Everybody has their own opinion, but I would say that they do not know any different,” Roseberry said. “They're well taken care of, and it's very seldom we have any problem getting them to eat and drink.”
Because nurse mare foals are bottle-raised, they tend to be very gentle and people-oriented, making them easy to market as riding horses or 4-H projects. Roseberry said he sells many for this purpose, keeps a few to add to his band of mares, and works with a farm in Ohio to successfully place those that don't find homes right away.