Bovine colostrum nutrient composition

The physiology of the ruminant placenta inhibits the transfer of large-molecular-weight structures in utero, thus making it essential that newborn calves receive a substantial amount of colostrum. Ruminant neonates must ingest colostrum for many reasons; however, attaining passive transfer of immunity from the dam is essential. Colostrum also contains other components that are important in satisfying nutritional requirements; high levels of fat, protein, vitamins, and minerals enable neonatal calves to begin building muscle, storing fat and initiating metabolic activities. Colostrum also provides high levels of growth factors and nucleotides, which have been reported to improve the maturation of intestinal tissue in growing neonates. Although average colostrum provides higher concentrations of nutrients compared with mature milk, there are differences among breeds of cows as well as parities that result in differing colostrum quality. For example, Holsteins produce colostrum that contains lower immunoglobulin concentrations when compared with other breeds. Also, younger parities produce colostrum with lower immunoglobulin concentrations compared with older cattle. Researchers have attempted to manipulate colostrum components through nutrition but have thus far only been successful in increasing certain vitamin and mineral concentrations. Continued research needs to evaluate whether other nutritional components of colostrum can be increased to improve neonatal survivability.