THE NEWBORN FOAL - PROBLEMS TO LOOK FOR
Dr Kirsten Neil BVSc (Hons) MACVSc MS Diplomate ACVIM
Specialist in equine medicine
Goulburn Valley Equine Hospital
A sound knowledge and understanding of what is considered to be "normal" in the newborn foal is vital. Early recognition of potential problems enables rapid intervention in the form of aggressive treatment and supportive care and can greatly improve the foal's chances of survival.
To look for problems in the newborn foal you need to start with the pregnancy itself. Was the duration of pregnancy normal? Was the mare ill? Was the mare dripping milk prior to foaling? Most mares will foal at 340 - 342 days; however, the gestational period (pregnancy length) varies between 320 - 370 days. Prematurity is usually defined as a foal with a gestational length of less than 320 days, but a foal born at 340 days may be premature if its' expected gestational length was 360 days. Common causes of prematurity include infection or inflammation of the placenta (placentitis) and illness in the mare. Signs of placentitis include early bagging up, dripping milk prior to foaling and occasionally vaginal discharge. If any of these signs are seen, contact your veterinarian as the mare will require treatment. The foaling itself is also important. The foaling process is rapid in a mare compared to other species, and when things go wrong there isn't much room for error. Prolonged and difficult foalings (dystocia) need rapid intervention and veterinary attention. Abnormalities during pregnancy or during the foaling process itself make the foal a "high risk" foal. Don't be deceived if these foals appear normal at birth - a foal's condition can deteriorate rapidly and they should be monitored closely.
What is "normal" in the first few minutes of life?
In the first 30 seconds after the foal is born, the foal will take gasping breaths. The normal respiratory rate in the first 5 minutes is 40 - 60 breaths per minute. This can be counted either by watching for movement of the chest or for flaring of the nostrils. If the foal's respiratory rate is lower, stimulate the foal by rubbing the foal and sit the foal up (the foal's blood oxygen level is higher when the foal sits up compared to lying down). The foal's heart rate in the first five minutes should be greater than 60 beats per minute. If the heart rate is lower, the foal will need immediate veterinary attention. This can be counted by placing the palm of the hand on the chest immediately behind the elbow. Most foals in the first five minutes of life will be able to sit up, and usually will shiver. Foals should have a suckle reflex by 20 minutes (assessed by placing your finger in the foal's mouth, and the foal should curl its tongue and suck). The normal foal will stand within an hour, and should nurse from the mare in the first three hours. Once the foal is 3 hours old, its respiratory rate lowers to 30 - 40 breaths per minute, will minimal effort to breathing. The foal's heart rate will increase to around 100-130 beats per minute.
What to look out for
Early signs of problems can be detected by looking at both the mare and the foal. Signs that the foal is not nursing enough are that the mare's udder will be full and dripping milk. The foal may be weak, quiet, lying down often, have droopy ears, trouble latching onto heat, or not nursing at all. The unresponsive recumbent foal will need veterinary care. Some foals have difficulty finding the teat and nursing, and may require help. Foals that cannot nurse at all will often need a feeding tube placed into the stomach by your vet until they can nurse on their own. The foal's gums should be pale pink. Pale, purplish and yellow gums are all abnormal.
The first faeces that the foal passes is termed meconium. Meconium is easily recognized as brown firm faeces, compared to milk faeces which are soft and yellow in appearance. If the newborn foal is stained with brown fluid that looks like meconium, this is a sign that the foal was stressed in the uterus, which in turn usually indicates that the foal will be ill. Meconium should be passed in the first 12-24 hours. Straining may be a sign that meconium hasn't been passed, and the foal may require an enema. Diarrhea in foals may be normal ("foal heat diarrhea") or a sign of infection. Foal heat diarrhea usually coincides with the mare's first heat at 9-10 days, but can occur in foals from 5 - 15 days. Foals with foal heat diarrhea have no other signs of disease or inflammation, remain bright and continue to nurse. Foals with diarrhea that appear ill require rapid treatment to prevent dehydration. I consider a foal with diarrhea in the first few days of life to be due to infection (sepsis) until proven otherwise.
Foals will typically urinate in the first 8 hours (slightly longer in colts). The urine is usually clear, and if the urine is strong and concentrated, the foal is dehydrated. Other signs of dehydration include dry tacky gums and sunken eyes. Straining may also be a sign of problems with the urinary tract, such as a ruptured bladder. However, foals can have a ruptured bladder and still be urinating normally.
The average bodyweight for a newborn Thoroughbred foal is approximately 50 kilograms, and foals should gain around 1 kg a day. The milk that the mare first produces is called colostrum. Colostrum contains antibodies that the foal relies on for defense against disease - horses differ from other animals in that no antibodies can cross the placenta. A foal requires 1-2 litres of good quality colostrum. Good quality colostrum is thick yellow milk. Quality can also be easily measured using a colostrometer (good quality colostrum measures at 23% or a specific gravity of 1.060). Factors which affect the quality of colostrum include age of the mare (old mares typically have lower quality), running milk prior to foaling and illness in the mare. Colostrum is best absorbed by the foal in the first 12 hours (up to 18 hours), as specialized cells in the intestine of the foal that are required to absorb colostrum are only present for this time. Foals should have blood taken at around 24 hours of age to check that their antibody levels are adequate (called an IgG test). Foals with low antibody levels (failure of passive transfer) will usually require a plasma transfusion to help boost their levels and protect them against disease.
Foals should have minimal effort to breathing. Horses cannot breathe through their mouth - a foal that is open mouth breathing should be treated as an emergency as this is a sign of severe respiratory distress. Premature, septic and dummy foals can all have respiratory problems, and pneumonia is common in foals. If your foal is panting or not breathing well, call your veterinarian. Foals can have very subtle outward signs of what is actually severe respiratory disease. Oxygen is often a valuable supportive therapy used in hospitals and neonatal intensive care units for sick foals with respiratory problems.
The foal's eyes should be looked at closely. Sunken eyes are a sign of severe dehydration. Some foals are born with turned in eyelids (entropian). This may also develop secondary to dehydration. The turned in eyelid will rub on the eye and can cause ulcers on the cornea. Some improved with fluids and other need an injection into the eyelid or sutures to get them back into the normal position. Watch for cloudy eyes also - uveitis (inflammation) is not uncommon in septic foals. Some can be so severe that the eye is a cloudy yellow colour.
Foals should not have milk coming out of their nose when they drink or cough. Some dummy foals do not swallow properly initially, however this can also be a sign of a cleft palate - a hole in the roof of the mouth that communicates with the pharynx and nasal passages. Have your veterinarian check the foal if this is occurring.
Care of the umbilicus is important. The umbilicus can be dipped or sprayed with antiseptic - either dilute iodine/betadine (no stronger than "weak tea" in colour as it can be very irritating to the skin) or dilute chlorhexidine (1:4 dilution with water). Foals that are laying down a lot will need to be watch more closely. Watch for bleeding, discharge or swelling, or urinating through the umbilicus (patent urachus) - call your veterinarian if you see any of these signs. Umbilical infections are common - remember just because the external section of the umbilicus appears normal, the internal structures can still be infected. An ultrasound examination may be required.
Other specific problems or diseases
Sick foals will often have more than one problem at the same time. A few of the more common conditions are described below. "Dummy" foals are discussed at length in an accompanying article.
Signs of prematurity include small body weight, soft silky hair coat, floppy ears and flexor laxity (tend to walk on the heels). These foals may just need a bit of help or they can need intensive care and a lot of veterinary attention. They have trouble regulating their temperature and glucose levels, and their organs may not have matured fully yet. Incomplete ossification of the knee and hock bones is common - if these foals are allowed to exercise they can cause a lot of damage and even crush the bones especially in the hock. The best way to assess this is to xray the knees and hocks - we tend to xray them every week initially then at regular intervals as a guideline as to when they are ready to be let out of the stable.
Premature foals often have other problems as well. They are often septic and will require antibiotic treatment. Foals that are born over term and are small can have similar physical characteristics and problems as premature foals (called dysmature foals).
Sepsis is the leading cause of death in new born foals. Signs can include uveitis, reddened coronet bands, or localized signs of infection such as pneumonia or diarrhea. These are often the really sick foals that need immediate intensive veterinary treatment. We take cultures of the foal's blood to try to isolate the causative bacteria, do blood tests to check the foal's white cell count, and will often check the foal's IgG level (antibody level) a number of times, as even if they initially had received enough antibodies they will use these antibodies up quickly and will often require a plasma transfusion.
Neonatal Isoerythrolysis (NI)
NI is a syndrome in foals caused by a blood group incompatability between the foal and the mare. The mare produces antibodies against the foal's red blood cells and the foal absorbs these antibodies when it drinks the colostrum. Signs can appear even up to 7 days of age but are more common in the first 3 days. These foals are normal at birth then become depressed and weak with an elevated heart rate, and will have yellow discoloration of the gums and white of the eyes (jaundice). The foal's red blood cells are destroyed (hemolysed) and often a blood transfusion is required as the foal becomes anaemic. A mare that has had a NI foal before is at risk of having another one. Tests can be done to check that the mare and stallion are compatable before breeding. If your mare has had an affected foal before, do not let the newborn foal drink from her at all in the first 48 hours. The mare will need to be stripped out to get rid of all of her colostrum, the foal muzzled and fed colostrum and milk from another mare.
Contracted tendons are more common in front legs than back legs. The foal will tend to stand on the toe and not be able to weight bear on the entire surface of the hoof, some can't even stand on the toe and if left to their own devices would stand on the front of the pastern or fetlock. The degree of contracture varies - some foals are able to stand and walk without much help, others can't stand at all. Treatment varies depending on the severity. Oxytetracycline is actually an antibiotic but when used at a different dose helps to relax the tendons (this shouldn't be used if the foal's kidneys are not functioning well). Some require splints that need to be changed daily. Each foal varies as to what veterinary treatment it will require. Other problems to look out for are angular limb deformities (bent legs) - a lot of these will improve in the first few days or week. If in doubt, have your veterinarian examine the foal.
Lameness or joint swelling in the foal should always be assumed to be infectious. Although we often think that the mare has stepped on or kicked the foal based on the sudden onset of lameness, unfortunately infection in the joint or bone is more likely. Bone or joint infection can influence whether the foal will be able to perform as an athlete. However, with early aggressive veterinary treatment, a number of these foals are able to race successfully.
Noticing the early signs of illness in a foal can make a big difference in terms of the foal's well being. Sick foals are a medical emergency - call your veterinarian if your foal is not doing well or just doesn't seem right before it gets to the stage of being dull, recumbent and unresponsive. Early treatment by your veterinarian or referral to a hospital facility can be crucial for success, both in terms of a normal healthy foal and ultimately the chances that the foal will be able to perform athletically at a later stage.