for all mammalian eukaryotic cells ie cow , chicken ,human etc require growth media that contains FBS https://en.wikipedia.org/wiki/Fetal_bovine_serum this extracted from the foetus of cattle, otherwise the cells cannot survive outside of the a live mammal. it is not vegan or vegetarian in the slightest
Thank you
FBS is used because it's versatile, whereas chemically-defined media have to be painstakingly reformulated for different cell lines. It's not a hard requirement.
The meat needs to feed on vitamins and minerals. It is real meat at the end of the day.