What is the difference between colostrum and regular milk of sows for piglets?

Antibodies in sow's blood can't enter the fetus through placenta, so piglets are immune virgins with almost zero antibodies after birth. Colostrum contains a large number of antibodies (maternal antibodies) from sow blood. Although this antibody is polymer protein, most of it can enter the pig's blood (IgG) through the intestinal wall, thus playing a role in systemic immunity and disease resistance.

Therefore, piglets must eat enough colostrum to have strong disease resistance. The absorption time of maternal antibody is limited, which decreases with the extension of birth time and ends within dozens of hours after birth. This termination phenomenon is called closing the door. Therefore, the sooner you eat colostrum, the better. Piglets can be breastfed three or four times within 12 hours after birth, with a total amount of 40 ml. Piglets can grow healthily.

Some unabsorbed antibodies (sigA) are called local antibodies, which can attach to the surface of intestinal mucosa to prevent bacteria from invading from the intestine and play a role in local immunity and disease resistance. Therefore, colostrum plays a very important role in the prevention of systemic and local diseases in piglets. Netizens suggested that it is difficult for piglets to survive without colostrum. People who eat less colostrum or eat too late have weak disease resistance and are prone to get sick. Only when they ingest enough colostrum can they have strong disease resistance and grow up healthily.

Although the antibody concentration in normal milk is much lower than that in colostrum, it still contains some antibodies. Most of these antibodies are local antibodies (sigA) synthesized by breast lymphocytes, which are not absorbed by the intestine, but can be attached to the intestinal mucosa to prevent bacteria from invading from the intestine, thus playing a role in local immunity and disease prevention. This is the so-called constant breast immunity. Although there are many reasons for diarrhea after weaning, the loss of immune protection of breast milk is also an important reason.