Neonatal Foal Nutrition

Newborn foals have minimal liver glycogen stores, and the drop in blood glucose in the first hour or so after they are born is a motivation for them to stand up and nurse. The first fluid in the mare’s udder is colostrum, which provides antibodies but also contains protein, energy, and some vitamins. Colostrum is rich in energy, providing about twice as much as the same volume of mare’s milk. Newborn foals don’t consume a large volume at each nursing, but by nursing as often as eight times an hour, they do manage to ingest a lot of colostrum.

A foal weighing 110 lb (50 kg) drinks about 15 liters of mare’s milk each day. This provides about 7,500 to 9,000 calories, which exceeds maintenance requirements by about 5,000 calories. This energy fuels rapid growth: on average, foals in their first month of life gain 2 to 3 lb and become 0.3 to 0.4 cm taller each day.

Foals that are unusually small or thin at birth may have experienced less than optimal prenatal nutrition and could be at a greater than normal risk for infection and other health problems. If the mare has been grazing fescue pastures, it is possible that she will not produce milk in the quantity and quality needed for optimal foal growth. Foals that seem to be nursing all the time but not gaining weight may not be getting enough milk to satisfy them, especially if the mare’s udder appears to be flat rather than full of milk.

Foals that nurse less frequently than normal could have problems with sucking, swallowing, or digesting the mare’s milk. Mares with a very full udder or that are dripping or streaming milk may have foals that are not consuming enough milk and therefore will not grow well. The foal’s weight, wither height, and body condition should be tracked regularly so that any pattern of abnormal growth will be detected. A steady, smooth growth curve is desirable and seems to lead to fewer developmental orthopedic problems in foals, weanlings, and yearlings.