Colostrum is the first milk a mare produces. It is also known as first milk and is thicker and more yellow in color than the milk the mare will produce later. Colostrum is rich in essential nutrients such as fats, proteins, vitamins, and minerals. In addition, colostrum contains important antibodies and immunoglobulins that support the foal’s immune system. These antibodies help protect the foal from diseases and infections during its early life.

Low Immunity

Foals receive very few antibodies from their mother while still in the womb, even less than other young mammals. This is because these antibodies cannot pass through the placenta into the foal’s bloodstream. As a result, foals are born with an incomplete immune system. The foal’s body must learn as quickly as possible after birth which substances to fight off. Therefore, every foal must ingest enough colostrum shortly after birth. This is an essential part of building immunity against pathogens. Foals that do not receive enough antibodies through colostrum are at high risk of diseases and even fatal infections.

First 24 Hours Are Crucial

It is crucial that a foal receives enough colostrum within the first 24 hours after birth. During this period, the foal’s intestines are particularly permeable to larger molecules. The necessary antibodies are often large protein molecules. Only colostrum, the first milk, contains these antibodies. After 24 hours, the foal can no longer properly absorb antibodies from colostrum because the lining of the small intestine then closes to these large molecules. By absorbing antibodies, the foal gains stronger "passive immunity," which is essential for its health and growth. Foals that receive enough colostrum have a lower risk of diseases such as diarrhea and pneumonia. Besides antibodies, colostrum also provides a high amount of energy, giving newborn foals a strong boost.

Not Enough Colostrum?

If a foal does not receive enough colostrum, various problems may arise. The risk of infections increases significantly, and growth disorders, nutritional deficiencies, and diseases may occur. This can even lead to the foal’s death. A healthy foal can drink from its mother within two hours, but sometimes the foal does not drink enough in the first few hours after birth or struggles to find the teats. In such cases, you can help by milking the mare and feeding the foal with a cup or bottle. Sometimes, a mare does not produce enough colostrum. In that case, artificial colostrum can be supplemented, which is available from a veterinarian. If you are unsure, the veterinarian can also perform an antibody test on the foal within a day and take appropriate measures if the results are concerning. If a foal appears lethargic, weak, or sluggish, always contact your veterinarian immediately—do not wait and see! Foals are extremely vulnerable and can deteriorate rapidly within just a few hours. It is better to provide an extra dose of artificial colostrum than to lose a foal!