What is the biggest unassisted calf you have had? Had one today that was 137. Cow is maine/shorthorn, bull is simm/angus. Was not execting this big of a calf out of this cow, but her first calf weighed 90lbs. So she has a large pelvis. It is also a heifer, vet was shocked by that. The calf even got right up and nursed. Amazing!!