How to reproduce fish fry

Fish fry is also called "fish flower". Newly hatched young fish usually have a body length of 6mm to 9mm. There are artificially propagated fish fry and natural fish fry from rivers. So, how do fish fry reproduce?

First, how to reproduce fish fry?

Fish out the mature male and female fish into the basin, grasp the male and female fish separately with both hands, and gently squeeze the abdomen. When you see the female fish eggs and male spermatozoa excretion, gently stir the water surface with your hands, and distribute the fish eggs evenly on the screen. The screen is placed in a foam box with green moss and exposed to sunlight at a temperature of 22-26 ℃. Remove the unfertilized eggs every other day and wait for the fry to break its shell after the eggs are fertilized. After the fish fry has broken its shell, it is ready to feed.

What is the open feed for fish fry?

1. Rotifer

Rotifer has good palatability, the content of crude protein is the highest, the content of crude fat is second only to egg yolk, and it contains a large number of unsaturated fatty acids necessary for fish fry. The swimming speed is lower than that of 0.02cm/s, and it is evenly distributed in the water layer. Rotifer can grow and reproduce in the seedling water, which not only maintains the stability of its nutrients, but also has little pollution to the seedling water. In addition, the research on rotifer cultivation methods is very rich, and the cultivation technology is relatively mature, which can ensure a sufficient source of rotifer, so rotifer is an effective way to solve the open bait of fish fry, reduce the production cost and improve the survival rate and quality of fish fry.

2. Algae

Algae are smaller than rotifers and are suitable to be used as opening bait at the initial stage of fry opening. With the growth of fish fry, the mouth cleavage becomes wider, and rotifer becomes the most suitable bait. The two can complement each other.

3. Egg yolk

Egg yolk is a kind of commonly used fish fry opening bait. In production, the egg yolk can be filtered through 80 mesh sieve silk to make the egg yolk particles smaller, so that they are uniformly distributed in the water, and the suspension time can be kept at about 1 hour. If the feeding amount is controlled in a proper range, the egg yolk can be better eaten by fish fry. However, it should be noted that this kind of bait is easy to settle and lose, and it is easy to cause water quality deterioration after entering the water, resulting in slow growth of fish fry and low survival rate.

4. Soybean milk

Soybean milk is rich in protein, which can meet the nutritional needs of fish fry, but soybean milk has low nutritional value, difficult to digest, low absorption rate, easy to form suspended matter in water, affects dissolved oxygen, and is easy to ferment, so most soybean milk mainly plays the role of fertilizer and water. promote the rapid reproduction and growth of plankton in the water, and indirectly provide bait for fish fry.

5. Aquatic products preparation

Aquatic microecological agents have the advantages of small size, no toxic side effects, no pollution and residues, which can effectively improve the ecological environment of culture, enhance immune ability, inhibit pathogenic microorganisms, and greatly improve the growth rate and survival rate of fish fry.

The success or failure of fry cultivation has a direct impact on economic benefits, so we must be more careful in the process of fry culture.