Early embryo culture and morphological observation experiment
Early embryo culture and morphological observation experiment
This experimental method was obtained from the official website of Chongqing Medical University
Operation method
Early embryo culture and morphological observation experiment
Principle
Chicken embryonic development can be divided into two stages: the development of the egg-forming stage and the development of the chick-forming stage.1. The development of the embryo during egg formation, i.e., the development within the mother's body, is the development of the egg-forming stage. The development process of this stage is: fertilized egg → egg cleavage → blastocyst stage → proto-gut stage. When the embryo develops to the proto-gut stage, it has been differentiated to form endoderm and ectoderm, which is shaped like a disk-like body from the appearance, i.e. the embryonic disk, when the egg is discharged from the body, the embryonic development stops immediately due to the decrease of the temperature.2. Embryonic development in the process of hatching After the egg is discharged from the body, it will be kept in the environment below 18℃, and the development of the embryo will be in the basic state of quiescence. When incubated, the embryo begins to develop. The period during which the embryo develops during incubation is called the incubation period. The incubation period of chickens is 21 days. After the breeding eggs are hatched, the embryo is formed in the protoglossal stage at the same time, the epiblast is like a saucer-shaped disk, at its end, the cells are constantly concentrated towards the midline, forming a band of cells called the protoglossus. The cells of the protostriatum are gradually transferred between the ectoderm and endoderm through the bottom of the protocoel, and expand to both sides respectively; these cells located between the endoderm and ectoderm are called mesoderm. The cells of the protostriatum also gradually pass between the ectoderm and the shenoderm and extend forward, respectively, to a structure called the cephalic process, which later develops into the notochord. The notochord is the longitudinal support organ in the embryonic stage, which is eventually replaced by the spinal column. As the embryo continues to develop, various glands, organs, bones, muscles, skin, feathers, and beak are gradually formed from the ectoderm, mesoderm, and endoderm, and finally the new organism, the chick, is formed.
Materials and Instruments
Fixative Saline Carmine Staining Solution Move 1, embryo culture: different fertilization time fertilized eggs, indicating the date and time, placed in a warm box, the temperature should be maintained at 37 ℃ ~ 38 ℃ between the temperature of the warm box to put half a cup of water to maintain the appropriate temperature. For more product details, please visit Aladdin Scientific website.
Incubator Deep ceramic bowl Curved tip Straight tip small scissors, sharp tip surgical forceps Straws Petri dishes
2, embryo extraction: each group (6 people) take different incubation time (3 days, 7 days, 10 days) eggs each 2, placed in warm water (the best raw salt brine) gently rolling, to be free to stand still, the embryonic disk that is located in the upper part of the warm water with pointed tweezers will be exposed to the surface of the eggshell gently broken, with tweezers to peel off the eggshell, so that all the embryonic disk is exposed with a curved scissors to cut along the edges of a round embryonic disk in a circle (in order to prevent) Cut a circle along the edge of the round embryonic disk with curved scissors (to prevent the egg white from rolling and the embryonic disk from reversing, the egg white can be sucked out partially with a pipette), move the embryonic disk to a petri dish with pointed tweezers, and wash it with physiological saline for several times, and get rid of the yolk that is adhered underneath the embryonic disk and the yolk membrane on the embryo in the saline water. The saline was sucked out with a pipette, and the embryonic disk was pressed flat against the bottom of the Petri dish and fixed for 5 to 10 minutes.
3, staining the embryo immersed in borax cochineal solution for 20 minutes.
4, making chicken embryo mount, the embryo disk directly mounted on a slide, absorb excess water.