Equine Health Library



Newborn foals are at risk for a variety of conditions associated with abnormal events during late pregnancy, delivery and/or the first few weeks of life. Examples of potentially life-threatening conditions that can arise during the early postpartum period include overwhelming bacterial infection (septicemia), peripartum asphyxia syndrome (dummy foal syndrome, neonatal maladjustment syndrome), prematurity/immaturity and birth trauma (fractured ribs, ruptured bladder).

Older foals aren’t out of the woods. As they explore their environments and encounter other foals and mares, they can be exposed to a variety of viruses, bacteria and parasites that increase the risk for respiratory disease and diarrhea.

You’ll want to have frequent conversations with your veterinarian before breeding and during your foal’s first year. Together, you and your veterinarian can create a healthcare plan customized for your farm.


Work with your veterinarian to develop a customized vaccination schedule that considers your region of the country, endemic diseases on your farm and your foal’s risk of disease exposure. Risk factors to review include how many other mares and foals your foal will contact during the first year of life and whether your foal will remain on your farm or travel to other locations when the dam is rebred, or they are sent for training.

Preventing disease through a strategic vaccination program is safer, easier and more economical than treating the sick foal.

Timing of the first vaccinations is critical. The maternally derived colostral antibodies that provide the foal with temporary protection are the same antibodies that prevent the foal from mounting an acceptable immune response to vaccines that are administered too early. Simply observing a foal nurse from its dam is not a guarantee that the foal has absorbed adequate amounts of colostral antibodies.

Recommended vaccination timing

Around four to six months of age, your foal is ready for his first vaccinations. Here is a recommended schedule for vaccination. Talk your veterinarian about which risk-based vaccines are needed for your farm and geography.

Click on the link to download your Equine Health Library Foal Vaccination Record
Click on this link to view the AAEP Foal Vaccination Chart on the AAEP website

Newborn Diseases – Septicemia

One of the most common and life-threatening conditions affecting newborn foals, septicemia is an overwhelming bacterial infection that results in bacteria and their toxins entering the bloodstream.

Once bacteria gain entry to the bloodstream, they can travel rapidly throughout the foal’s body, which results in a variety of localized infections including pneumonia, diarrhea, joint, growth plate and bone infections (joint ill, physitis, osteomyelitis), hepatitis (liver infection), and meningitis (brain infection).

The foal may acquire the bacterial infection in utero from an infected placenta (placentitis). During delivery and/or after birth, bacteria may enter the newborn foal via the lungs through inhalation, the intestinal tract via ingestion or the umbilicus via the umbilical vessels and urachus (structures contained within the umbilical cord).

Most common bacterial pathogens that cause septicemia

  • E. coli
  • Klebsiella
  • Pasteurella
  • Actinobacillus
  • Salmonella
  • Streptococcus zooepidemicus
  • Staphylococcus sp.
  • Clostridium perfringens
  • Clostridium difficile

Injected sclera in a septic foal. Note the prominent appearance of the blood vessels in the white portion of the eye.

Hyperemic membranes in a septic foal. These mucous membranes are severely inflamed
and are usually associated with the presence of bacteria and /or their toxins in the bloodstream.

Signs of septicemia

  • Loss of suckle (quickly accompanied by marked udder distension in the dam)
  • Depression
  • Weakness
  • Collapse
  • Elevated heart rate
  • Cherry red gums
  • Injected (blood shot) sclera

Initially, newborn foals may not develop a fever. Some foals may even have sub-normal temperatures during early sepsis. Extremities, such as ear tips, muzzle and limbs, will become cool to the touch as affected foals become “shocky” due to collapsing lung and heart function.

Septicemia is a life-threatening condition where hours matter. If your foal shows any of these signs, contact your veterinarian immediately.

Diagnosis and treatment

Your veterinarian’s workup will include a physical exam and laboratory blood work (white blood cell count, red cell count, IgG concentration, serum chemistries to evaluate kidney and liver function and electrolyte balance) and cultures of blood and other body fluids. Septic foals typically have a low white blood cell count, low blood glucose (sugar) level and show signs of dehydration.

Aggressive therapy is required to treat and save septic foals.


  • Antibiotic therapy
  • Cardiovascular support (including intravenous fluid therapy)
  • Antibody administration (often in the form of plasma)
  • Respiratory support (such as intranasal oxygen administration)
  • Good nutritional support
  • Excellent nursing care

Other complications from septicemia

Foals that survive the initial wave of septicemia may later develop localized infections in other organs. It is important to work closely with your veterinarian and monitor your foal for signs of such infections. Foals with pneumonia typically develop a fever. Very young newborn foals may not have a cough or nasal discharge initially but usually will display an increased rate and effort of breathing.

If bacteria affect the joint or growth plate, your foal may exhibit distention of the affected joint or painful swelling around the infected physis in the region just above the joint. With either condition, the foal will be lame. Lameness in any young foal is cause for concern and should prompt a call to your veterinarian. Infections of the joints and/or bones can be career ending if not treated aggressively with local and systemic antibiotics and anti-inflammatory medications.

Diarrhea is often the result of bacterial infection and can quickly result in dehydration and electrolyte imbalances. Salmonella and Clostridia sp. are the most common bacterial causes of diarrhea in foals.

Foals suffering from meningitis, a less common sequela of sepsis, can seizure and become stuporous or comatose. Hepatitis frequently will cause signs of jaundice. Infection and/or inflammation within the eye cause uveitis resulting in tearing, squinting and a cloudy, yellow discoloration in one or both eyes.

Severe Combined Immunodeficiency Disease (SCID)

An autosomal recessive trait in Arabians, SCID results in an inability to produce B and T lymphocytes that are critical in protection against a wide variety of bacterial, protozoal, viral and fungal infections. Affected foals are unable to produce antibodies of their own.

Once the antibodies they absorbed from colostrum are gone, they become susceptible to a host of infections. Foals are normal at birth but develop life-threatening infections between two days and several months of life. Affected foals also have very low numbers of lymphocytes, a special type of white blood cell.