After the first day, most researchers suggest that a calf receive colostrum at 8 to 10 percent of body weight. The higher figure gives you room to error on the estimated weight. As a guide, the birth weights of Holstein and Brown Swiss calves average between 90 and 100 pounds, Ayrshire and Guernseys 65 to 75 and Jerseys 55 to 65. The recommendation is on a daily basis, so you would feed 5 pounds per feeding, or 10 pounds per day to a 100 pound calf. If the cow is milked before calving, leaks milk before she calves, or the colostrum appears abnormal, feed the newborn calf frozen colostrum saved from another cow.
Most cows produce more colostrum than needed by their calf.
Only first-milking colostrum from older cows should be saved. Generally, the colostrum from older cows will have a higher level of immunoglobulin than that of first calf heifers. The colostrum should be thick like freshly melted ice cream. The thicker it is, the higher the immunoglobulin in content. Measure the amount needed for one feeding and freeze in a plastic bag or covered container to prevent dehydration.