[Smart Farmers] How do fish swim from the ocean to the table? Baby fish fry also live in a big house!

Have you ever wondered how delicious seafood appears on the table? How do sturgeons "swim" from the rivers and lakes to the table? Behind all this, there is an important "role" - the embryo incubator.

Embryo incubator is one of the important equipment in aquaculture process, its role is to hatch fertilized eggs under suitable conditions. There are many important factors to consider in the incubation process to ensure the hatching rate and seedling survival rate.

First of all, the hatching water temperature is an important factor to be considered during the hatching process. Generally speaking, the hatching water temperature of sturgeon should be controlled between 10℃-18℃, which is the temperature range adapted to the main farmed sturgeon in my country. If the water temperature is too high or too low, it may have a negative impact on the hatching rate and the survival rate of the seedlings. Therefore, it is necessary to measure the water temperature regularly during the hatching process and take corresponding measures to adjust it.

Secondly, the dissolved oxygen content during the incubation process is also one of the key factors affecting the hatching rate and seedling survival rate. If the dissolved oxygen is insufficient, the fish eggs may be affected by lack of oxygen, resulting in a decrease in the hatching rate and survival rate. Therefore, during the incubation process, ≥5mg/L dissolved oxygen is required, and the dissolved oxygen content in the water can be increased by using an aerator or adding oxygen.

In addition, in order to avoid strong light exposure, direct sunlight should be avoided during the incubation process. Strong light may have a negative impact on the development and survival rate of fish eggs. Therefore, when choosing an incubator, you should choose an incubator with better shading effect, or take shading measures during the incubation process.

The length of incubation time is also a factor that needs to be considered. Generally speaking, it takes about 5-7 days for sturgeon embryos to hatch from fertilized eggs. During this process, it is necessary to pay close attention to the development of the embryos. If the incubation time is too long or too short, it may affect the hatching rate and the survival rate of the seedlings.

The fertilization rate is also the most direct factor affecting the hatching rate. If the fertilization rate is not high, many eggs cannot be fertilized, and these eggs are prone to Saprolegnia during the hatching process. Saprolegnia will damage the shell of the eggs, further affecting the hatching of other eggs. Therefore, special attention should be paid to the prevention and control of Saprolegnia during the hatching process. You can pick out the dead eggs in time and often use methylene blue to prevent and control Saprolegnia.

In the late stage of embryonic development, about 120-140 hours later, the embryo will break through the membrane. During this process, you can see a series of developmental processes of the embryo, such as the appearance of eyespots, heartbeats, and trunk twisting. Once the embryo is hatched, the next step is to start the cultivation of seedlings.

Embryo incubator is one of the important equipment in aquaculture. It can make aquatic organisms "swim" onto our dining table. In the process of using the incubator, only by paying attention to details and doing a good job of prevention can the hatching rate and seedling survival rate be improved. Let us look forward to more aquatic organisms bringing more deliciousness and surprises to our lives!

Produced by: Popular Science in China to Benefit Farmers

Scientific Advisor: Researcher Hu Hongxia, Institute of Fisheries Sciences, Beijing Academy of Agricultural and Forestry Sciences

Co-ordinators: Liao Danfeng, Zheng Fengmao, Wang Changhai, Zhang Ruijie

Planning: Wu Yuetong

Editor: Hou Siyu (internship)