What are the specific requirements for calves to consume colostrum?

Because the immunoglobulins in colostrum are absorbed into the blood through the intestinal wall in an undigested state, only the immunoglobulins that enter the bloodstream have an immune effect. Subsequently, the permeability of the intestinal wall decreases, and large protein molecules can no longer pass through the intestinal wall into the blood. This phenomenon is called gut closure or contraction of the intestinal mucosal epithelium. At birth, the absorption rate of immunoglobulins in calves is as high as 50%, and from 24 to 36 hours after birth, very little or none is absorbed. Therefore, calves must be given and given enough colostrum within the first day after birth. The first colostrum feeding should be as early as possible, generally within 1 hour after birth. Feed it once the calf can stand on its own.