Foals: The First Hours of Life
Dr. Mary Rose Paradis
In human neonatology a system called the Apgar test has been developed to evaluate a newborn's condition after delivery. Newborns are rated at one minute, five minutes and 10 minutes after delivery on five qualities: appearance (color), pulse (heartbeat), grimace (reflex), activity (muscle tone), and respiration (breathing). Veterinarians have modified this system to fit the foal. It is a good guideline for assessing problems and for determining whether aggressive resuscitation is necessary.
Four parameters are measured in the foal system: heart rate, respiratory rate and pattern, muscle tone, and the reaction to nasal stimulation with a straw. The test is performed immediately after birth. A value of 0 to 2 is assigned to each measurement and a final score is determined by adding up the values. A total score of 7 to 8 indicates a normal foal; a score of 4 to 6 suggests that intervention is needed; and scores of 0 to 3 represent severe problems with likelihood of not surviving.
Assigned Value: 0
Heart and pulse rate: Undetectable
Respiration (rate and pattern): Undetectable
Muscle tone: Lateral recumbency, or lying on her side and unable to rise
Suckle reflex: Absent
Assigned Value: 1
Heart and pulse rate: Less than 60 beats/min
Respiration (rate and pattern): Slow, irregular
Muscle tone: Lateral recumbency, evidence of some muscle tone
Suckle reflex: Weak suckle
Assigned Value: 2
Heart and pulse rate: Greater than 60 beats/min
Respiration (rate and pattern): Greater than 60 breaths/min, regular
Muscle tone: Able to maintain sternal recumbency, which is sitting up on the brisket with the legs tucked under the body
Suckle reflex: Strong suckle
Normal foals have a heart rate of greater than 60 beats/minute. You can usually feel the heart beat of a newborn foal by placing the palm of your hand on the left side of the chest just behind the elbow. Each time you feel a vibration or thump, this counts as one heart beat. Alternatively, you can listen with a stethoscope if you have received training. If you count the beats for 15 seconds and multiply by four, you get the heart rate per minute.
The respiratory rate of the newborn foal can vary greatly but it is usually over 60 breaths per minute. This can be determined by counting the number of times the foal's chest rises over 15 seconds, and again, multiplying it by four to get the breaths per minute. A range from 60 to 100 breaths/min is acceptable. Assessing the respiratory effort is equally important . The normal foal has a regular, gentle rising and falling of the chest wall. If the foal has a breathing problem the effort increases so that the foal's ribs and /or abdominal muscles contractwith each breath. In severe respiratory problems, the foal resorts to aggressive movement of the abdomen, a sign the diaphragm is working to extreme. This may be a sign that the foal is having trouble clearing the normal fluids from the lung.
Soon after birth, foals begin to right themselves and sit sternally with the sternum on the ground. They should be actively moving their legs and holding their head up. Lateral recumbency, or lying on the side, is abnormal for the newborn. Although foals normally lie on their side when sleeping, they will go sternal or stand if stimulated. A foal that does not respond in this way is abnormal.
The suckle reflex is generally present within five minutes of birth. It may be weak at first, but it should continually strengthen over the first hour of life. Absence of a suckle or the persistence of a weak suckle may indicate that the foal was deprived of oxygen during the birth process.
Newborn foals should be stimulated by rubbing them briskly with a dry towel. This causes the normal foal to shake her head and move around. More aggressive intervention is needed if the foal presents with a score of less than 6. If the foal is not breathing then you need to help clear the lungs of fluid. To aid in clearing excess fluid from the lungs, the lying foal's hind quarters can be elevated over the level of the head, and the chest gently patted with a cupped hand (coupage). This loosens mucus in the lungs and provides drainage. Mouth-to-nose resuscitation can be performed by holding one nostril and the mouth of the foal closed while you blow into the other nostril. You should be able to see the chest moving if you are filling the lungs. Cardiac massage may be needed until the veterinarian can provide more effective treatment.