This study describes a method of obtaining primary cultures from the cerebral cortex and the hypothalamus of bovine fetuses. We describe here the influence of tissue origin, developmental stage and culture medium conditions on cell differentiation and prevalence of neurons vs glial cells. To identify optimal conditions for obtaining and growing viable neurons and astrocytes in culture, we tested early, middle and late stages of development. Explants from cortex, early stages (week 10 of pregnancy out of 36) and low fetal calf serum concentration (1%) yielded maximum amounts of neurons. Fresh and thawed tissues gave comparable results.