Programmed cell death (PCD) has been proposed to occur in vitro after withdrawal of growth factors and serum deprivation. In the present study the influence of brain derived neurotrophic factor (BDNF) and different serum (FCS) concentrations on viability, survival and apoptotic cell death of cortical cells from 8 days old chicken embryos after 3, 5 or 7 DIV was investigated. Results show that BDNF as well as fetal calf serum (FCS) influence the metabolism of neurons. Furthermore, serum, but not BDNF, is able to protect neurons from cell death. For the detection of apoptosis TUNEL-staining and DNA gel electrophoresis was performed. These methods supplied contrary information about the type of cell death in neurons raised without serum. The first technique indicates the occurrence of apoptosis whereas the second suggests necrosis. In addition, by the means of DNA gel electrophoresis it was exhibited that cortical cells from 8 days old chicken embryos are committed to undergo PCD already in vivo at time of preparation.