The first and most important feed given a new born dairy calf is colostrum. Colostrum is the dairy calf's primary source of nutrients. It also provides essential and irreplaceable antibodies that help to maintain the animal's health and reduce mortality rates. Colostrum is secreted from the mammary glands before and shortly after parturition.
True colostrum is obtained only from the first milking.
True colostrum has twice as much dry matter, three times as many minerals, and five times as much protein as whole milk. The high content of vitamins A, D, and E in colostrum is especially important because the newborn calf has low reserves of these vitamins. In addition, colostrum lines the walls of the calf's digestive tract, thereby protecting the animal against many diseases. The relatively low lactose content in colostrum reduces the incidence of diarrhea. And the presence of the enzyme inhibitor, trypsin, enables the calf to better absorb and assimilate colostrum antibodies.