Premature Foal

In order to put some credibility to this story we have to endure a short mathematics lesson to verify the gestation period of the foal. First of all most resources state that horses foal within a range of 320 to 360 days after the foal is conceived. For miniature horses, we use the following formula:


The mare in question had foaled on April 7. Our records indicated that she was rebred on April 23 through May 1. In June we had the mare ultrasounded. At that time she was verified in foal. Based on the size of the pregnancy the veterinarian estimated the breeding date to be April 29 to May 1. Using our formula, one would expect that by subtracting 35 days from May 1, the theoretical foaling date should be approximately March 25 the following year. This date had to be correct since she had just given birth and had bred back on her first heat cycle after foaling.


At about nine months of pregnancy we always get a little edgy in anticipation of the foaling season and start watching the mares very closely. Shortly after January 1, we came out one morning to feed. We found this mare down in the loafing shed. She was not in labor. We determined this since she was not showing signs of uterine contractions. There were no fetal membranes protruding from her vulva. There was no telltale smell of amniotic fluid on her tail. She did show signs of diarrhea. She could hardly stand up, even when prodded. When we finally did get her up, she barely walked and was highly disoriented. It reminded us of our cow when it had “milk fever” (phosphorus/calcium imbalance). The previous night, the mare had shown no outward signs of problems. We immediately rushed the mare to the Oregon State University Veterinary Teaching Hospital.

Had it not been for the outstanding diagnostic skills, emergency room techniques, and aggressive treatment regimen by the staff at the Vet School there is no doubt we would have lost this mare. Due to her diarrhea and resulting loss of fluids, the mare’s body chemistry was seriously out of balance. This in itself was life threatening and also accounted for the reason the mare was unable to coordinate walking. We also found blood in the mare’s stool which was very alarming. As we left the mare in the hands of the vet school. We were warned that her condition was life threatening and that the chance for aborting her foal was extremely high.

The mare spent two weeks at the vet school. She was diagnosed with Necrotizing Colitis. This is an inflammation of the colon in which the lining of the bowel actually starts sloughing off, causing the horse to bleed from the rectum. No actual cause of the colitis was ever pinpointed. We returned to pick up the mare who had lost a little weight as a result of the ordeal; but was amazingly still carrying her foal. It was now mid-January


We were starting to watch the expectant mares from the closed circuit cameras in the barn each night. During foaling season this becomes a major ordeal. While you are staring at the same picture on the monitor for endless days you become a little punchy and come up with crazy names for these programs such as “General Stall Watch” or “Days of Our Mares”. On February 4th, about 5 a.m., Joanne wandered down to the barn to take a first hand look an one of the mares under the camera. She had been acting a little curiously. Everything was fine there. As she headed back, she peaked in to the stall where our recuperating mare was. Much to her amazement she was greeted by a itty-bitty black pinto foal standing (well sort-of), dried off, attempting to nurse on her mother.

After suffering a few moments of paralysis, Joanne’s neurons started functioning on overtime. The first, fleeting thought was how could I have miscalculated. The second, it’s alive, let’s get down to business. Treat the umbilical stump with nolvasan. Blanket the foal to help her conserve body heat. Check the mare to assure the placenta has passed and to assure she has milk. Check the foal to observe if it is nursing aggressively.

Oh boy! Here’s a problem. Either the foal has an exceptional appetite or the mare is dry. Upon feeling the mare’s udder, Joanne discovered that it was completely flat. This is highly abnormal for a mare with a newborn foal. Joanne was unable to strip any milk from the nipples. The foal was constantly trying to nurse. This wouldn’t seem reasonable with a newborn foal who was getting its fill. It became very clear that this foal had not received any nourishment since birth. Since we had not witnessed the birth, it was difficult to tell how long the foal had been alive. It was standing and its hair coat was dry so we estimated that it had been a number of hours since foaling.


All foals are essentially born on the verge of critical condition unless Mother Nature’s steps proceed in order. It is imperative that newborns receive nourishment soon after birth for two very important reasons

1. Foals are essentially born in an energy deficit situation. They have very few reserves of energy to maintain body heat and carry out bodily functions. Without “groceries” from mom or another source within the first few hours of life foals start showing signs of bodily stress and depression.

2. Mothers first milk (colostrum) provides antibodies (infection fighters). Foals are born with an immature immune system that is not yet fully functioning. The foal does not have antibodies in its bloodstream to fight off infectious organisms that are constantly present in the air we breathe, for example. If the foal does not receive antibodies through the mare’s colostrum within the first 6-12 hours of life, it will not have resistance to common infections such as pneumonia, influenza, tetnus, and other common diseases. Without these defenses, the foal will more than likely perish within a short period of time after birth.

Normally we “bank” colostrum by saving a small percentage produced by each mare then freeze it. Unfortunately, due to an extended power outage for a period of days we had lost our supply. We had no choice but to rush the foal to the OSU Vet School.

Upon arriving, the filly was examined. The vital signs were taken. Blood was drawn for evaluation. We discussed what had occurred so far. When we told the OSU staff this filly was approximately six weeks premature. The alarm bells started going off with the Vet School staff. We figured her gestation had only been 281 to 282 days. OSU stated foals surviving that were this premature was almost unheard of. Much like with premature humans, under-development of the lungs and insufficient surfactant in the lungs can lead to major respiratory complications.

Shortly after we got to the vet school the filly began to lose her vitality. Since she had not received any nourishment, her little fire had started to go out. She lost her suckling reflex. She did not want to stand on her own. Her temperature began dropping. Fortunately, by a combination of keeping her warm on a heating pad, tube feeding her a commercial milk replacer, and IV feeding, she pulled through that crisis and recovered her strength and will to live.


Since the mare was dry and no colostrum was available, the vet school decided to perform a plasma transfusion to the foal. This is a procedure where donor horses are highly immunized against all forms of diseases. A small portion of their blood is then harvested. The plasma portion of the blood is extracted and stored for later uses such as with our foal. The plasma, packed with antibodies, is then intravenously transfused slowly into the foal’s bloodstream. This plasma mingles with the foals blood and the antibodies then provide a defense against infection until the foal’s immune system fully develops and produces adequate antibodies to protect itself. When we left the vet school, the foal was looking somewhat revived from when we had brought her in. That was encouraging. The veterinarians reminded us, however, that the situation with her lungs was serious and that she was, by no means, out of the woods.

The filly spent two weeks in the vet hospital. As warned, she developed pneumonia. Through aggressive antibiotic treatment and constant monitoring, she pulled through the ordeal very well. The filly weighed approximately 14 lbs. when we had taken her to OSU. When she was released, two weeks later, she had gained one pound. She was taking the bottle vigorously every two hours. Her vital signs were stable. Her blood work was looking satisfactory. We felt pretty good given the numerous problems that she had fought her way through.


Suffice it to say it would be hard to find anything much more demanding than an orphaned foal. We built a tiny stall in our bedroom. She was constantly jumping out of the stall to chase us around the house. Our feeding schedule of every two hours was not acceptable to her. She would wake us up in the middle of the night nickering from her stall when she was hungry.

The foal did not seem, at first, to be taking in an adequate amount of groceries. The resources we have read state that newborns should consume between 15% and 25% of their body weight per day in milk. The commercial milk replacer was not a hit. She was not consuming close to this level of food so we were getting concerned about malnutrition. We had heard about raising horses on goat’s milk. Fortunately we had a milk goat farm down the road. When the filly got a taste of this, she was like an entirely different animal. She became ravenous. It seemed like she would drink as much milk as we would put in front of her. We fed her at two hour intervals around the clock. Her weight shot up. Her energy shot up. We became a little concerned and were careful to keep her intake between the 15-25% parameters per day, as we had read. We had to be concerned about regularity of bowel movements. The filly appeared to become constipated occasionally. We were forced in a couple of instances to use an enema after an extended period of constipation.


We maintained this regimen for approximately one month. We were introducing the filly to grain and alfalfa leaves in her stall. She was taken out daily in the hopes of stimulating her to eat grass. Since we were not very good about demonstrating grazing techniques, she wasn’t making much progress. We heard of a mare that had just lost a foal. We contacted the owners. The mare had not had a chance to bond with the foal. They graciously consented to allow us to attempt to graft our foal onto their mare. The mare was very receptive and immediately claimed our foal as her own. Our foal had some difficulty figuring out how to nurse from the mare. We had to bottle feed her for a couple of days until she was getting all of her nourishment from the mare. The situation worked out very well all the way around because the foal was then provided with herd experiences that she would have otherwise not have received by being hand raised. We, of course were also relieved from the major burden of feeding and caring for the totally demanding foal.


We learned a number of things from this experience. The one critical care tidbit that we will always remember is that if we have a foal that has not nursed, we will definitely get food into it as soon as possible. In this case the mare was the first to foal of the year and we had no other mares to milk. As stated we had no colostrum to give. The veterinary resources we have consulted since this incident give a formula for “fortified milk”. 8 oz. 2% cow’s milk + 1 tsp Karo syrup. If we were in this situation again, we would mix this up and give some to the foal as we were heading to the Vet School. Obviously this is only to provide the newborn with nourishment to keep the fire going on an emergency basis. This formula does nothing to account for immune deficiency or other problems.

As it turned out, this filly, after all of her trials has flourished. We never cease to be amazed by the heart and will to live these horses have when given a reasonable opportunity and there is a good working relationship between the horse owner and the treating veterinarians.