Like all agricultural products, the price of eggs is cyclical. From the Mid-Autumn Festival in 20 14 to the Spring Festival in 20 15, the price of eggs continued to rise. Due to the blindness and lag of market regulation, some places increased the scale of breeding and expanded the output of eggs. Excessive output, people's demand is limited, and the supply exceeds demand, which strengthens the competition among egg merchants, so the price is constantly decreasing.
Egg formation
When the oocyte grows and develops in the ovary, the yolk substance gradually accumulates and increases in the egg. The yolk substance takes concentric circles as layers, forming a yolk structure with dark yolk and light yolk alternately arranged, and the yolk core is formed by white yolk, which extends to the animal pole, with the end slightly enlarged, and the expanded part is called Pan Shi nucleus.
White yolk contains more protein, while yellow yolk is rich in lipids. There is little cytoplasm in the egg, which is mainly located in an area at the top of the animal polar yolk, where the nucleus is located. With the increase of yolk substance in oocytes, the volume becomes larger and follicles protrude from the surface of ovaries.
When ovulating, the primary oocyte completes the first mature division, discharges the first polar body and becomes the second polar oocyte. Then it enters the metaphase of meiosis. During ovulation, the theca ruptures, and the secondary oocyte is released from the ovary, which is immediately involved in the very active oviduct umbrella.