Colostrum, also known as beestings or first milk, is the first form of milk produced by the of (including humans) immediately following delivery of the newborn. Most species will begin to generate colostrum just prior to giving birth. Colostrum has an especially high amount of bioactive compounds compared to mature milk to give the newborn the best possible start to life. Specifically, colostrum contains antibodies to protect the newborn against disease and infection, and immune and growth factors and other bioactives that help to activate a newborn's immune system, jumpstart gut function, and seed a healthy gut microbiome in the first few days of life. The bioactives found in colostrum are essential for a newborn's health, growth and vitality.
At birth, the surroundings of the newborn mammal change from the relatively sterile environment in the mother's 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 gastrointestinal tract of the neonate, as the gut plays an important part in both the digestive system and the immune system. Colostrum has evolved to care for highly sensitive mammalian neonates and contributes significantly to initial immunological defense as well as to the growth, development, and maturation of the neonate's gastrointestinal tract by providing key nutrients and bioactive factors.
Colostrum also has a mild laxative effect, encouraging the passing of the baby's first Human feces, which is called meconium. This clears excess bilirubin, a waste-product of dead red blood cells which is produced in large quantities at birth due to blood volume reduction from the infant's body and which also helps prevent jaundice.
Colostrum also contains a number of growth factors, such as insulin-like growth factors I (IGF-1), and II, transforming growth factors alpha, beta 1 and beta 2, fibroblast growth factors, epidermal growth factor, granulocyte-macrophage-stimulating growth factor, platelet-derived growth factor, vascular endothelial growth factor, and colony-stimulating factor-1.
Bovine colostrum and human colostrum are highly similar in their makeup, both containing many of the same antibodies, immune and growth factors, and other nutrients. Because they share so many of the same components, the way they work in the body is also highly similar. The benefit of bovine colostrum for human health has been studied in many areas including:
The role of colostrum for newborn animals is to provide nutrition, and essential protection against infection while the immune and digestive systems are developing and maturing. Bovine colostrum provides macro- and micro-nutrients, as well as growth factors, cytokines, nucleosides, oligosaccharides, natural antimicrobials, antioxidants; and a range of immunoglobulins such as IgG, IgA, IgD, IgM and IgE. It is well established that minimal levels of IgG are essential to prevent failure of passive transfer. The iron-binding glycoproteins lactoferrin and transferrin in bovine colostrum assist in attacking pathogens by impacting their cell membrane and making them more susceptible to the immune systems attack by neutrophils. Cytokines present in bovine colostrum enhance B and T cell maturation and increase endogenous antibody production. They also play a major role in regulation of epithelial cell growth and development, proliferation, and restitution. Transfer factors enhance the activity of T cells. Other growth and immune factors such as IGF-1, IGF-2, FGF, EGF, TGF, PDGF, etc.
Bovine colostrum's components benefit the immune and digestive health of animals of all ages and species. Bovine colostrum's vast array of bioactive components collectively increase resistance to infection and disease caused by a wide range of pathogens including bacteria and viruses. The quality of the colostrum is essential in providing the essential benefits. Both contaminated early bovine colostrum at the farm level or late transition milk or milk are poor sources of the important colostral components necessary to maintain life and achieve and maintain healthy animal maturation and homoeostasis. Bovine colostrum also is beneficial in repairing or healing intestinal damage as well as increasing the absorption of nutrients from the GI tract. These properties and benefits are consistent among human and animal species.
The transition from fetal to neonatal and shift from maternal to environmental reliance requires an abrupt immunological change. In calves, for example, colostrum provides a significant benefit in neonatal intestine development. This includes villus area, circumference, height and height/crypt ratio. Colostrum is critically important to calves and foals in order to prevent failure of passive transfer and death. Calves, foals and piglets with low IgG levels have an increased risk of morbidity and mortality. Bovine colostrum can be used to reduce the duration and severity of infections so it can be a useful tool to include in the reduction of antibiotic use. Finally, another important and valuable benefit of colostrum is in the reduction in scours and increase in average daily weight gain all of which have a significant farmer and ultimately consumer benefit.
Bovine colostrum plays a role in increasing Ig levels, increasing lymphocyte proliferation stimulating activity and increasing phagocytosis activity. These are supported by other components of colostrum which further enhance the activity of the immune response. The iron binding glycoproteins lactoferrin and transferrin in bovine colostrum assist in attacking pathogens by impacting their cell membrane and making them more susceptible to the immune systems attack by neutrophils. Cytokines present in bovine colostrum enhance B and T cell maturation and increase endogenous antibody production. They also play a major role in regulation of epithelial cell growth and development, proliferation, restitution. Transfer factors enhance the activity of T cells. Other growth and immune factors such as IGF-1, IGF-2, FGF, EGF, TGF, PDGF, etc. Colostrum contains glycomacropeptides which help to regulate appetite.
Bovine colostrum has been shown to enhance immune response in animal models including canine, feline and equine animals including maintaining a higher level of vaccine antibody response over time and for a longer period than the vaccine alone. Animals fed colostrum had a significantly higher local immune status resulting in higher IgA through GALT stimulation. Colostrum also plays a key role in reduction or prevention of diarrhea and reduction in respiratory illness.
Although bovine colostrum has been consumed by humans for centuries,
The gut plays several important roles including acting as the main pathway for fluid, electrolyte and nutrient absorption while also acting as a barrier to toxic agents present in the gut lumen including acid, digestive enzymes and gut bacteria. It is also a major immunological defence mechanism, detecting natural commensals and triggering immune response when toxic microbes are present. Failure of homeostasis due to trauma, drugs and infectious microbes not only damages the gut but can lead to influx of damaging agents into the bloodstream. These mechanisms have relevance for multiple conditions affecting all areas of the world and socioeconomic groups such as ulcers, inflammation, and infectious diarrhea. There is currently much interest in the potential value of colostrum for the prevention and treatment of these conditions as it is derived from natural sources and can influence damaging factors through multiple pathways including nutritional support, immunological intervention (through its immunoglobulin and other anti-microbial factors) and growth/healing factor constituents. As pointed out by Kelly, inconsistency between results in some published studies may be due in part to variation in dose given and to the timing of the colostrum collection being tested (first milking versus pooled colostrum collected up to day 5 following calving).
Some athletes have used colostrum in an attempt to improve their performance, decrease recovery time, and prevent sickness during peak performance levels. Supplementation with bovine colostrum, 20 grams per day (g/d), in combination with exercise training for eight weeks may increase bone-free lean body mass in active men and women.
Low IGF-1 levels may be associated with dementia in the very elderly, although causation has not been established. Malnutrition can cause low levels of IGF-1, as can obesity. Supplementation with colostrum, which is rich in IGF-1, can be a useful part of a weight reduction program. Although IGF-1 is not absorbed intact by the body, some studies suggest it stimulates the production of IGF-1 when taken as a supplement whereas others do not.
The Isle of Man had a local delicacy called "Groosniuys", a pudding made with colostrum. In Finland, a baked cheese called Leipäjuusto is traditionally made with either cow colostrum or reindeer milk.
A sweet cheese-like delicacy called 'Junnu' or 'Ginna' is made with colostrum in the south Indian states of Karnataka, Andhra Pradesh and Telangana. It is made with both cow and buffalo milk; in both cases it is the milk produced on the second day after giving birth which is considered best for making this pudding-like delicacy. Colostrum is in very high demand in these states, resulting in product adulterant.