Colostrum: The thin, yellow, serous fluid secreted by the mammary glands during pregnancy and immediately postpartum before lactation begins. It consists of immunologically active substances, white blood cells, water, protein, fat, and carbohydrates.Milk: The white liquid secreted by the mammary glands. It contains proteins, sugar, lipids, vitamins, and minerals.Milk, HumanMilk Substitutes: Food BEVERAGES that are used as nutritional substitutes for MILK.Immunity, Maternally-Acquired: Resistance to a disease-causing agent induced by the introduction of maternal immunity into the fetus by transplacental transfer or into the neonate through colostrum and milk.Animals, Newborn: Refers to animals in the period of time just after birth.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Lactation: The processes of milk secretion by the maternal MAMMARY GLANDS after PARTURITION. The proliferation of the mammary glandular tissue, milk synthesis, and milk expulsion or let down are regulated by the interactions of several hormones including ESTRADIOL; PROGESTERONE; PROLACTIN; and OXYTOCIN.Animals, Suckling: Young, unweaned mammals. Refers to nursing animals whether nourished by their biological mother, foster mother, or bottle fed.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Immunoglobulin A, Secretory: The principle immunoglobulin in exocrine secretions such as milk, respiratory and intestinal mucin, saliva and tears. The complete molecule (around 400 kD) is composed of two four-chain units of IMMUNOGLOBULIN A, one SECRETORY COMPONENT and one J chain (IMMUNOGLOBULIN J-CHAINS).Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Animal Nutritional Physiological Phenomena: Nutritional physiology of animals.Lactoglobulins: Globulins of milk obtained from the WHEY.Lactoferrin: An iron-binding protein that was originally characterized as a milk protein. It is widely distributed in secretory fluids and is found in the neutrophilic granules of LEUKOCYTES. The N-terminal part of lactoferrin possesses a serine protease which functions to inactivate the TYPE III SECRETION SYSTEM used by bacteria to export virulence proteins for host cell invasion.