Directly after birth, you can give a newborn calf as much colostrum as it can drink. It is no problem when this means several litres in the first feeding. As long as you take care that it will not end up in the airways (bronchial tubes), it will "never be too much".
During the first two days a calf needs to drink at least 4 to 5 litres of colostrum per day in total.

Click here for more information about feeding colostrum.