The third trimester of pregnancy is a crucial period because of the rapid growth the calf undergoes and because it is our opportunity to improve cow body condition prior to calving if needed. It is easy to forget those things when we can’t see the growing calf and a growing winter coat may be deceptive when it comes to body condition.
Here is a helpful breakdown of when the third trimester begins based on various dates for the start of the spring breeding season. Fetal growth is exponential during this time with blood flow increasing 3 to 4-fold mid to late gestation. In the last 60 days, 75% of growth occurs, or 60 pounds of an 80-pound birth weight. The total weight of the pregnancy with fetus, fluids and membranes at calving is around 100-150 pounds total. This process is fascinating.
