Nusrat Zareen, Uzma Shahid.
Reproducing windowing technique for naked eye observation of chick embryo morphogenesis.
Ann Pak Inst Med Sci Jan ;7(3):146-9.

Background: Human embryos are not easily available for teaching purposes. Embryology teachings rely mostly on simulators. Fantasying the embryological stages falls far behind in giving an exact picture of the events to undergraduate medical students. This study uses chicken embryo biological models for observing naked eye development stages. These model systems not only prove to be a realistic approach to the subject of embryology but also provide an ideal experimental medium for research. Objective: To device a model system for easy access to the developing embryo, maintaining a natural developing environment as close as possible. Study Design: Descriptive case series. Materials & Methods: This study was conducted in the Anatomy department of of Islamabad Medical and dental college, Islamabad Pakistan. Small windows were made on the shells of fertilized chicken eggs. One edge of the circular window was left hinged as a lid to the shell. The eggs were incubated under standard conditions. The developing embryos were daily taken out and day wise development was studied by just lifting the lid without sacrificing the embryo. Results: In this study three batches, each comprising of 6 fertilized eggs were traced for developmental mile stones via windowing technique. Formation and growth of the embryonic membranes, central nervous system, circulatory system, eyes, limbs, skin, wings and folding of the body were directly observed and the developmental time line also traced in 100% embryos. Conclusion: This system provides a media for in ovo experimentation for the researchers without much manipulation to the natural environment.

PakMediNet -Pakistan's largest Database of Pakistani Medical Journals - http://www.pakmedinet.com