South American serum, often referred to as South American Fetal Bovine Serum (FBS), is a type of fetal bovine serum sourced from cattle in South American countries, such as Brazil or Argentina. It is widely used in cell culture as a supplement to provide essential growth factors, proteins, and nutrients that support cell growth and proliferation. South American serum is favored for its lower risk of contamination with certain viruses and pathogens compared to serum from other regions.