Colostrum

Form of milk produced immediately following the delivery of newborn On the left is human breast milk expressed on day 4 of lactation, and on the right is breast milk expressed on day 8. Colostrum has a yellowish hue. Bovine colostrum (beestings) next to spray-dried colostrum powder Colostrum (from Latin, of unknown origin), also known as foremilk, is the milk expressed by the mammary glands of a female mammal during the first few days following delivery of the newborn. Animal colostrum may be called beestings, the traditional word from Old English dialects. Most species begin to generate colostrum just prior to giving birth. Colostrum contains antibodies to protect the newborn against infection, and immune and growth factors. Colostrum is beneficial for a newborn's growth and immune system in calves and humans. At birth, the newborn moves from the sterile conditions of the uterus, with a constant nutrient supply via the placenta, to the microbe-rich environment outside, with irregular oral intake of complex milk nutrients through the gastrointestinal tract. This transition puts high demands on the neonate's gastrointestinal tract, which plays an important part in the immune system.