Avian cell cultures grown in an open system (dishes) without CO2 incubator, and their use for virus cultivation.

An organic buffer, N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), in a culture medium made it possible to culture chick embryo fibroblast (CEF), duck embryo fibroblast (DEF), and chick kidney (CK) cells in an open system (dishes) under incubation in a bacteriological incubator, requiring no CO2 incubation. CEF, DEF, and CK cells cultured with this system were suitable for cultivation of avain viruses such as Newcastle disease virus, CELO virus, Marek's disease virus, and turkey herpesvirus.