Colostrum immune cells (as lymphocytes) and many antibodies such as IgA, IgG, and IgM. These are some of the components of the adaptive immune system. In preterm infants some IgA may be absorbed through the intestinal epithelium and enter the blood stream though there is very little uptake in full term babies. This is due to the early "closure" of the intestinal epithelium to large molecule uptake in humans unlike the case in cattle which continue to uptake immunoglobulin from milk shortly after birth. Other immune components of colostrum include the major components of the innate immune system, such as lactoferrin,
Colostrum natural colostrum nearly always had higher antibody titers than did the hyperimmune version clinical trials have shown that if the immunization is by surface antigens of the bacteria,the Bovine Colostrum Powder can be used to make tablets capable of binding to the bacteria so that they are excreted in stools. This prevents the successful colonization of the gut, which would otherwise lead to bacteria releasing enterotoxigenic materials. These small immune signaling peptides (PRPs) were independently discovered in colostrum and other sources, such as blood plasma, in the United States, Czechoslovakia and Poland. Hence they appear under various names in the