What Is Fetal Bovine Serum and Why Is It Used in Labs? Kumar Jeetendra | February 18, 2025 Fetal Bovine Serum (FBS) is essential in areas like medical research and helps maintain your laboratory cultured cells alive and well. FBS is procured from fetal calves, so naturally, it is stocked with a multitude of proteins, growth factors, and nutrients, all of which aid in supporting cells. FBS presence has made its adoption an …