Terry C. Gerros, D.V.M.
The signs of illness in foals are often vague and nonspecific.
This means that you should be familiar with normal behavior in
order to recognize problems early. Dramatic changes in a foal's
condition can occur very rapidly. The wait and see approach used
in adult equine medicine can be disastrous when dealing with the
neonate. A short time delay in the institution of therapy can
make the difference between success and failure. It is my opinion
than any foal which appears ill constitutes an emergency. Below
are listed the normal parameters for foals in the immediate
post-partum (post foaling) period.
Gestational age: 341 ñ 21 days. Range = 315 - 365 days.
Time to sucking reflex: Ave. 20 minutes post-foaling.
Time to standing: Ave. 57 minutes, range 15 - 165 minutes.
Time to nursing: Ave. 111 minutes, range 35 - 420 minutes.
Body temperature: First four days: 99 - 102F.
Heart rate: Ave. first five minutes: 70 bpm
Respiratory rate: First 15 minutes: 60 - 80 bpm, then 20 - 40
First urination: Ave. 8.5 hours after birth, colts earlier than
Meconium passage (first stool): Within first 24 hours.
Menace response (Blink response): Not present until 2 weeks of
Normal guidelines used to assess neonatal viability:
Adaptive response Time Elapsed Since Birth
Normal respiratory and cardiac rhythm Within 1 minute
Righting reflexes established Within 5 minutes
Sucking reflex established Within 30 minutes
Attempts to stand Within 60-120 minutes
Ability to stand unassisted Within 60-180 minutes
Nurses from udder Within 60-180 minutes
As I previously said, any of these parameters outside the given
normal range, either high or low, should be considered abnormal.
If they appear so, it is time to call your veterinarian.
Some abnormalities which you can pick up and give you an
indication that things are a miss include:
Increased passive range of motion of joints.
Tendon contracture. Flexor tendon laxity (walking on their
Angular limb deformities (eg.knock knee'd).
Entropion (lower eyelid rolled under).
Tipped ears, velvety hair coat (prematurity).
Heat, swelling, or pain at joints or physes (growth plate).
Fractured ribs associated with foaling (rapid, shallow
Umbilical or inguinal (scrotal) hernias.
Cleft palate (milk running out of the foals nose as it nurses).
Scoliosis (curved), kyphosis (flexion), or lordosis (extension)
of the spinal column.
Injected (blood shot) or icteric (yellow) sclera (whites of the
Straining to defecate or urinate.
Red line around the coronary band (will only be evident on white
Swollen, moist, leaking umbilical cord.
Foal wanders away from the mare or in unaware of the mare in the
Poor suckle reflex.
Placenta is thickened, discolored.
While we spend alot of time looking at the foal, don't forget
that the mare can give you an indication that the foal is
becoming ill before the foal shows a significant change in
character. Examine the udder, milk, and privates for signs of
disease or infection. A full tight udder indicates a foal that
isn't nursing. Malodorous uterine discharge may indicate the foal
has an infection which developed in utero.
Conditions associated with high risk newborn forals
Hydrops allantois General anesthesia
Colic surgery Endotoxemia
Excessive medication History of previous abnormal foal
Premature lactation Poor nutritional status
Prolonged transport prior to foaling
Conditions of labor or pregnancy:
Premature parturition Abnormally long gestation
Prolonged labor Induction of labor
Dystocia Early umbilical cord rupture
Meconium staining Placental abnormalities
Orphan Inadequate colostral intake\
Immaturity/prematurity Exposure to infectious disease
Specific diseases of the Equine neonate
It should be obvious to you that we can not possibly go every
disease condition which constitutes an emergency in the time
allotted to us. It is likely that the physical abnormalities
associated with trauma constitute an emergency and need not be
covered, except your initial management until the vet arrives.
Certainly there are going to be conditions which arise in which
nothing can be done, except euthanasia. This is something we as
veterinarians deal with on a day to day basis, and not something
we take lightly. I will outline some conditions which I deem are
not treatable medically or surgically, briefly, and then discuss
some of the more common diseases seen.
Ventricular septal defect
Trilogy/Tetralogy/Pentalogy of Fallot (multiple cardiac defects)
Choanal atresia* Fractured spine
Premature foal (less than 300 days into gestation)*
* Constitute diseases which may have a treatment option, however,
the prognosis going into treatment is grave.
Lacerations and long bone fractures can initially be managed with
pressure wraps and support bandages until the vet arrives. Unless
you have specific questions we won't go into this further.
The conditions I will concentrate on will include failure or
partial failure of passive transfer, neonatal isoerythrolysis
(red blood cell lysis), neonatal maladjustment syndrome, and
Passive transfer disorders of the foal
In order for the foal to fully fight off infection early in its
life, it must ingest colostrum (first milk) which contains the
antibodies which protect the foal from many diseases. There are
special cells in the gastrointestinal tract which will absorb
these antibodies. These special cells are replaced within the
first 36 hours of life, so it is essential that the foal nurse
within the first 6-8 hours of life, the time of peak absorption.
Antibody absorption decreases rapidly afterwards. We like to see
the foal nurse within 2 hours and certainly by 3 hours after
birth. The earlier the foal nurses, the more antibodies it
absorbs, the more protected it becomes. These foals do not show
any evidence of disease and a diagnostic test is the basis of
detecting the disorder.
Causes of failure of passive transfer
Premature lactation (loss of colostrum before birth).
Inadequate colostrum production by the mare or poor colostral
Delayed onset of sucking (foal that is slow to get up).
Malabsorption by the small intestine.
Prematurity: <320 days, the foal may be capable of absorption,
but colostrum may not have formed.
Detecting 800 mg/dl of IgG in the foal is considered to be the
minimum concentration for adequate passive transfer. Less than
400 mg/dl is considered to be complete failure of passive
transfer. These foals are considered to be at greatest risk for
any development of infectious disease. There are no specific
abnormal clinical signs associated with failure of passive
transfer and the foals act normally until they develop some
disease. How do you tell if the foal got a good quality colostrum
and an adequate amount?
If the mare dripped milk for any appreciable time before foaling,
assume that she has lost her colostrum. If you notice this
happening, milk her out and save that milk. Freeze it. Would I
collect the milk till she foals, you bet. If the mare doesn't
drip milk before foaling, collect some of the colostrum and
measure the specific gravity. An device used to measure
antifreeze in your car radiator will suffice. If all the balls
float, you can assume the colostrum to be of good quality. This
corresponds to a specific gravity of about 1.060. Of course, this
is a rough estimate. Once the foal nurses, you can measure the
IgG content at 18-24 hours after the foal nurses. Several tests
are available, some even foal side. The Cite Test can be
performed on whole blood, plasma, or serum and can be done on the
Treatment of this disorder depends upon when you detect a
problem. If you know the foal hasn't nursed and it is less than
12 hours old, oral administration of colostrum ( 3 liters) is the
treatment of choice, followed by testing for adequate absorption.
If the foal is over 24 hours old, a plasma transfusion is
required to bolster the IgG concentration. The foal may need
between 1 - 3 liters. Plasma administration should take place
over several hours, however, it may not be practical to
administer it this slowly. Adverse transfusion reactions include
shivering, elevated respiratory rate, anaphylactic reactions have
occurred and resulted in death.
Neonatal isoerythrolysis (ni)
This is a severe hemolytic disease caused by incompatibility
between the mare's and stallion's bloodtype. It is rarely seen in
maiden mares as the mare must be sensitized to antigens from the
stallion's red blood cells (RBC) in order to produce antibodies
against them. These antibodies are then concentrated in the
colostrum of the mare and passed on to the foal after birth. If
the foal has inherited incompatible RBC antigens from the
stallion and ingests colostrum containing antibodies directed
against those antigens, NI may ensue. Mares may become sensitized
by previous blood transfusion with blood of a similar type to the
stallion or by transplacental RBC leakage during pregnancy.
Foal born healthy, with onset of the desease between 6 - 96 hours
Severity of signs is dose dependant, peracute (found dead) to few
Packed cell volume (PCV) <20%.
Pronounced icterus (yellow, jaundice) of mucous membranes.
Tachycardia (elevated heart rate).
These foals usually are not febrile (fever) and may or may not
exhibit hemoglobinuria (dark colored urine).
The diagnosis is based upon clinical signs and cross-match the
mare and foal.
Treatment consists upon the severity of clinical signs. If
diagnosed before 24 hours of age, muzzle the foal, milk out the
mare and feed the foal colostrum from another source.
If the PCV is <15% or the foal is very weak, keep the stress to a
minimum. Blood transfusion will also be required at this point.
The mares washed RBC's provide the best source. If this is
impractical to accomplish, an aged gelding who has not had a
blood transfusion is an alternative source. Those horses known to
be A- and Q-type negative are good blood donors.
Other supportive care may be required, consult your vet.
Look for other problems.
Neonatal maladjustment syndrome (Barkers, Dummies, Wanderers)
A noninfectious central nervous system disorder of neonatal foals
associated with behavioral abnormalities. The syndrome usually is
first seen anytime after birth to 24 hours of age. These foals
may be completely normal at birth, had a normal gestation and
parturition. The foaling may have been difficult or the foal may
have suffered some hypoxic (low oxygen) episode.
The clinical signs associated with this disease relate to
derangements of cerebral function or spinal cord disease, or
Loss of suckle reflex
Aimless wandering, may appear blind
Hyperexcitable with jerky stiff movements or unresponsiveness
Extensor spasms of neck, limbs, paddling
Chomping or teeth grinding
Anisocoria (one dilated and one constricted pupil)
Abnormal respiratory patterns
Hypothermia (low body temperature), acidosis
Spinal cord signs:
Depressed local reflexes
This disease needs to be differentiated primarily from
septicemia. Often times these syndromes appear similar. A
complete blood count will help differentiate the two diseases.
Serum biochemistry panel may also show abnormalities in septic
foals where NMS foals will be normal.
Maintain body temperature, hydration, caloric intake, electrolyte
and acid-base balance, and blood glucose.
Oxygen therapy as needed
Ensure adequate passive transfer
Broad spectrum antibiotics.
This is a multisystemic disease and many of the patients
concurrently have ongoing sepsis, failure of passive transfer,
enteritis, ulcers, etc.
This is probably the leading cause of death in neonatal foals. It
usually involves a gram negative bacteria which gains access to
the circulatory system. The primary routes of infection are the
respiratory tract, gastrointestinal tract, and umbilical cord. It
may be acquired in utero or in the immediate post-partum period.
These foals may be born normal or are weak right after birth. If
they appear normal at birth, they may deteriorate in a matter of
hours. This out of all the diseases discussed previously is truly
an emergency and needs attention as soon as it noted the foal to
The clinical signs associated with septicemia include:
All ten signs listed under NEONATAL MALADJUSTMENT SYNDROME
Bright red mucous membranes (gums and conjunctiva)
Cyanotic (bluish) mucous membranes (gums)
Hemorrhages present on the gums
Injected sclera (blood shot eyes)
Elevated heart rate
Elevated respiratory rate
Unable to rise or unable to arouse
Straining to defecate
Grinding the teeth
This a disease syndrome which should not be handled in the field
and needs to be referred to a hospital. These foals require
intensive care and close monitoring. They may require oxygen
therapy, assisted ventilation, intravenous nutrition, and
constant nursing care. Broad-spectrum antibiotics, nonsteroidal
antiinflammatories, intravenous fluids, drugs which egulate blood
flow, are among the medications required to sustain life.
The most common disorder of the bladder of the newborn foal is
rupture. Most common in colts, it may occur in fillies. The
clinical signs are usually present within the first two days of
life and include straining to urinate, dysuria, depression, and
bilaterally symmetric distension of the abdomen.
Surgery is the treatment of choice and the success rate is high
is performed within the first 5 days of life. Emergency surgery
usually is not required. The greatest concern is the hyperkalemic
(high serum potassium) state the foal is in. Hyperkalemia can
cause profound cardiac disease which can result in death.