Foetal calf serum is a product, the precise content of which is unknown. Moreover, the content varies from batch to batch. This means that there can be big differences between FBS-batches with different amounts of endotoxins and other undesired elements as well as other unwanted, and unknown, substances which affect the growth of cell cultures in different ways. The use of foetal calf serum therefore makes scientific research less reliable, harder to reproduce and experimental results harder to compare. It is therefore much harder to make use of the research.
The use of serum replacements or serum-free media that contain the necessary constituents for culturing cells, including amino-acids, vitamins, lipids, salts and growth factors should be considered to achieve improved reproducibility and control over that of FBS in both the biotechnology arena and the academic research field.
-Adam Elhofy PhD., Essential Pharmaceuticals. Serum and its applicability and use in cell culture
The British scientific guidelines on good practice for use of cell lines in biomedical research now recommend use of defined serum-free growth media. Also the EU’s centre for validation of alternative methods, EURL ECVAM, recommends that researchers replace foetal calf serum with other nutrients – both to prevent the suffering of many animals and to obtain more reliable results. Its scientific advisory committee states directly:
The ESAC members recommend to use non-animal serum substitutes of fetal calf serum (FCS) and other animal derived supplements, whenever possible. For new in vitro culture test methods to be developed the ESAC strongly suggests the use of non-animal alternatives to FCS.
For methods forwarded to ECVAM for validation/prevalidation where this is not fulfilled a justification for future use must be provided, including measures to seek non-animal alternatives to FCS.”