How much weight will a calf gain per day for the first week of it's life? I had a heifer that had a bull calf about a week ago. I didn't get to weigh it until today and it weighed 95 pounds. By eyeball I thought it would weigh about 80 to 85 pounds when it was born. I have some smaller heifers getting ready to calve and I don't want any 90 pounders. The heifer calved with no problems but she weighed about 1100 pounds and she was an older heifer.