Researchers have created a technique for cultivating fertilized chick eggs without their protective shells. These eggs were placed into a transparent artificial culture container, enabling continuous observation of the chick embryo’s growth from the moment of laying until the hatching phase.
Scientists at the University of Tsukuba have introduced a method for culturing fertilized chick eggs without their shells. By using a transparent artificial culture vessel, they can observe the development of the chick embryo from laying to hatching in real-time.
The quest to study chicken embryonic development stretches back to Aristotle around 300 BC. Traditionally, observers had to break the eggshell to gain access to the embryo due to the shell’s opaque nature. This prompted efforts to create transparent artificial culture vessels. An earlier method involved removing embryos from their shells after three days of incubation, followed by hatching them in a transparent setup. However, when using this method for fertilized chick embryos immediately after laying (0-day-old embryos), normal growth was not achieved.
Upon investigating this problem, the researchers found that the yolk membrane surrounding the blastoderm—the region where cell division occurs during development—became desiccated by the third day of culture. To address this, they employed a rotary shaker with the top plate tilted at a 7° angle. This approach maintained moisture in the yolk membrane covering the blastoderm, which significantly increased the survival rate of the 3-day-old embryos. Moreover, as the embryos were further cultured through conventional shell-less techniques, development progressed, resulting in several normal chicks hatching successfully on the 21st day of incubation.
The findings from this research are anticipated to lay the groundwork for diverse applications, such as advancing chick embryo development studies, conducting toxicity evaluations, and exploring regenerative medicine possibilities.