When, or if, you ever care for an orphan foal, your first concern should always be getting colostrum into him – and not just at any point in time, but within the first few hours after foaling. “Foals are born naive, meaning they have none of their own antibodies,” says Pam Karner, VMD, of Starland Veterinary Services, in Trumansburg, New York. “So they’ve got to get colostrum within the first 24 hours and preferably within the first 12, because immunoglobulins (IgG, aka antibodies) in the colostrum are very large molecules, and after 24 hours the foal’s gut can no longer absorb them.”
In fact, a foal absorbs 85% of the colostral antibodies in six to eight hours.
Walden says she uses an older-type manual human breast pump to collect colostrum from her heavier-milking mares to freeze for future needs. And if the dam has died within the past few minutes, she milks out the colostrum from the mare’s udder.
Virginia Buechner-Maxwell, DVM, MS, Dipl. ACVIM, director of the Center for Animal Human Relationships at Virginia Tech, in Blacksburg, who has both raised orphan foals and worked with other owners of orphans, says this technique only works if the mare has just died (so the milk is not tainted).
“For foals that do not suckle well or are reluctant to eat, it’s best not to try to force them to eat, as the milk can easily end up in the trachea and cause pneumonia,” she says. “Instead, refrigerate the colostrum and immediately call your veterinarian to come look at the foal and provide the colostrum by passing a nasogastric tube and delivering it directly into the stomach.”
In the absence of mare colostrum, some horse owners have had success with colostrum from other species—particularly goats or cattle. From a veterinarian’s viewpoint, cow and goat colostrum might work in a pinch, but mare colostrum is ideal. Many large breeding farms bank and freeze mare colostrum in case they need it and could be a source for individual owners.
The best colostrum, regardless of species, contains a large amount of immunoglobulins that will protect the foal against common infections as well as local pathogens. Obtaining colostrum from local mares that are well-vaccinated against diseases such as influenza, herpesvirus, strangles, Potomac horse fever, rabies, and tetanus provides the best protection against bugs foals are likely to encounter, says Buechner-Maxwell.
“You want your foal to be protected from the pathogens around them, so you want them to get colostrum from animals in the same environment,” Karner says. “Once those antibodies are used up, the foal is making its own antibodies.”
When evaluating an orphan, Buechner-Maxwell right away uses a quick, simple, stall-side blood test to measure IgG transfer (the amount of antibodies received from the colostrum) and, so, check its immunity levels.
“If it’s inadequate, I’ll provide additional protection immediately,” she says.
The substitute might be a commercial colostrum replacement or plasma product. Commercial colostrum replacement products come in powder or paste form. Owners mix the powder with water (following manufacturers’ directions) and feed it in a bottle or pan; they can deliver the paste to the foal’s mouth.
“Colostrum replacement products raise the concentration of IgG in the foal’s bloodstream,” says Buechner-Maxwell. “However, it is not clear that providing IgG alone provides full protection, as mare’s colostrum contains many other beneficial elements (including some of the mare’s immune cells) besides IgG.
“Another alternative is providing equine plasma,” she adds. “If the foal is less than 6 to 12 hours old and is clinically normal, the plasma can be delivered orally. If the foal is older than 12 hours and/or has already received several feedings of milk or milk replacer or is ill, then the best way to deliver the plasma is through the intravenous route, which should be done by a veterinarian.”
Regardless of the source, always check blood concentrations of IgG after giving the foal a commercial product, she adds.
Foals that don’t receive colostrum within the first day after foaling are highly susceptible to infections from organisms that cause diarrhea (aka scours) and other bacterial and viral infections that can even progress to sepsis, a potentially deadly body-wide state of inflammation. It’s important to check IgG early on because “once an animal starts to get sick, especially an equine neonate, it’s really a downward spiral,” Karner says.
Diarrhea in foals can be life-threatening, so call your veterinarian if it occurs.