Development of shell-free culture methods for high hatchability bird embryos would be helpful for efficient generation of chickens transgenics, embryo manipulation, tissue engineering and basic studies in regenerative medicine. Studies on bird embryo culture methods include whole embryo culture using narrow window eggshells, surrogate eggshells, and an artificial container using a gas permeable membrane to achieve a high hatching rate of >50% using entirely artificial containers. Thus, our group established a simple method to cultivate chicken embryos with high hatching rate. We examined various cultivation conditions, including calcium supplementation and oxygen aeration methods. In embryo cultures where embryos were transferred to the culture vessel after 8 days of incubation, more than 90% of embryos survived until day 12 when polymethylpentene film was used as the culture vessel with calcium lactate supplements and distilled water. Aeration of pure oxygen to surviving embryos from day 8 resulted in no possibility of hatching until day 14. A single egg survives for up to 14 days. Most of the time they die on day 10. Only 2 days survive after the first experiment where the egg was on the 8th day of development. Thus, our laboratory failed to achieve a high hatching rate with this method of culturing chicken embryos using an artificial container. Say no to plagiarism. Get a Custom Essay on “Why Violent Video Games Should Not Be Banned”?Get Original Essay Fertilized chicken eggs, incubated in room air, were examined at 8, 9, 10, 11, 12 , 13 and 14 days of incubation. and compared to eggs incubated in 60% oxygen. Eggs incubated in an oxygen-rich atmosphere had lower carbon monoxide diffusion capacities, lower rates of oxygen consumption per gram of embryo, heavier embryos, and more advanced embryonic morphological development than eggs. incubated for the same time in ambient air. The lower rates of oxygen consumption per gram of embryo are consistent with an increased growth rate, because oxygen consumption (per gram of embryo) decreases as weight increases; the lower diffusion capacities of eggs incubated in 60% oxygen are interpreted to be due to either a decrease in the chorioallantoic capillary surface area or an increased thickness of the diffusion barrier between the chick's blood and the air, or both. To study the influence of eggshell on the process of mobilization of calcium from the shell by the chorioallantoic membrane (CAM), chicken embryos were maintained in long-term in vitro cultures without shells. Embryos without shells were severely calcium deficient and showed signs of developmental delay and abnormal skeletal calcification. Throughout development, calcium transport and calcium binding protein (CaBP) activities were decreased in the CAM of shellless embryos compared to those of control embryos developed in ovo. The levels of carbonic anhydrase activity expressed during development, however, remained similar. By means of a single CaBP radial immunodiffusion assay using specific anti-CaBP antiserum, the level of immunoreactive CaBP was found to be significantly increased in the CAM of shellless embryos. These studies indicate that the CAM of chicken embryos grown without shells is defective in..