Growth and differentiation of chicken embryos in simplified shell-less cultures under ordinary conditions of incubation.

The growth and differentiation of chicken embryos maintained in evaporating dishes as shell-less cultures were compared to that of control embryos in ovo under the same conditions of incubation. The development of cultured embryos appears to be indistinguishable from that of embryos in ovo up to 10 days of total incubation. Thereafter, the growth of shell-less embryos is significantly retarded as evidenced by morphological criteria of the Hamburger-Hamilton stages of development, body weight, tibia length, and total protein content. Cultured embryos are smaller in size than controls, but show normal morphological features including a fully-differentiated skeleton. Skeletal defects and other anomalies were not detected in any of the specimens studied. Limitations as to the use of the simplified method of culture are evaluated and discussed.