The goal of this project was to demonstrate shell-less chick embryo culturing as a potential experimental model in the field of developmental anatomy. Freshly laid, fertilized chicken eggs of “Egyptian Fayoumi” breed were obtained from Poultry Research Institute Punjab, Rawalpindi. The fertilized chicken eggs were preincubated for 33 hours under standard conditions of 37.5°C and 65-75% humidity, to bring them to stage 9 (29-33 hours embryo, 7 somites) of Hamburger and Hamilton staging system. After this period, the eggs were taken out of the incubator, placed horizontally, wiped with 70% ethanol and permitted to air-dry for 10 minutes to reduce contamination from the egg surface and also to ensure that the embryo was properly positioned. The eggs` contents were then transferred into the “culture containers” by cracking the undersides against an edge. The formation and growth of the embryonic membranes, the central nervous system – beginning from the vesicle stage, the circulatory system – including the heart, the eyes, beak, limbs, skin, feathers, wings and folding of the body were directly observed. Repeated successful culturing was attempted, tracing the developmental process of the embryo upto the 15th day of embryonic life at least after which the survivability period varied in different embryo cultures. The most advanced age reached in this project was day 19 of the embryonic life, which in researchers` understanding is the latest developmental stage in shellless environment described as yet. The normal hatching time of this breed is 21-22 days. The size of these embryos was smaller as compared to the embryos of the same age that carried out their development inside their shells.
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