Foals acquire all their immunity from their mother’s colostrum (first milk) in the first 24 hours of life. This is why vaccinating your mare one month prior to foaling is so important. Once your mare delivers it is important to witness your new foal nurse. Schedule an appointment for a neonatal exam when the foal is between 12 to 24 hours of age. During this exam, Dr. Winter will perform an IgG test which indicates the level of antibodies your foal has absorbed. The levels as described below give us information on any further treatment that may be required.

A plasma transfusion is recommended for foals that test less than 400 mg/dl. Without the plasma transfusion, they may develop a life threatening bacterial infection. When foals test between 400 to 800 mg/dl a plasma transfusion is also recommended but not necessarily required. They have a decreased immunity and an increased chance of developing a disease, depending on their environment and exposure risk. If a foal tests above 800mg/dl, a complete passive transfer has occurred and no further testing or treatment is required.