CATDOLL : CATDOLL: How do eels reproduce? Do they hatch from eggs?

1. How do eels reproduce? Do they hatch from eggs?

Reproduction technology of yellow eel 1. Natural reproduction When artificially breeding yellow eel, the purpose of self-reproduction of yellow eel can be achieved by strengthening feeding management and creating an ecological condition suitable for the reproduction of yellow eel. The main measures are: (1) Build a breeding pond or divide a piece of the breeding pond for breeding. In the breeding pond, a smaller young eel protection pond should be built. Leave more round or rectangular holes on the wall of the pond. The holes are separated from the breeding pond by fine-meshed wire mesh. Water can flow through the mesh, and young eels can enter the protection pond, while male and female parent eels cannot enter, so as to protect the young eels. (2) Put 3 to 4 parent eels (mostly female) with a body length of 25 to 30 cm per square meter in the breeding pond. Regardless of male or female, individuals with yellow color and strong body should be selected, and they should be carefully managed 1 to 2 months before reproduction and fed with high-quality animal bait such as earthworms and maggots. (3) Simulate the spawning environment of yellow eels in the field. Build earth ridges around the breeding pond (at a certain distance from the pond wall) and in the middle. The ridges are about 20 cm wide and 10 to 15 cm above the water surface. Plant some weeds on the ridges. (4) Keep the environment quiet during the spawning period of yellow eels. The water in the breeding pond must first be maintained in good water quality through fine streams or constant seepage. The incoming water must first pass through the young eel protection pond and then slowly flow into the breeding pond. The stimulation of the slow flow can induce the eel fry to swim upstream and enter the protection pond. (5) Throw some soft and hairy objects such as loofah tendons and willow roots in the breeding pond and protection pond to help the eel fry hide and live, and also facilitate artificial collection and transplantation. (6) Yellow eels lay eggs in batches, and the spawning period lasts for a long time. After the breeding season of the year is over, you can use the cage capture method to catch all the parent eels and raise or process them separately to prevent the young eels from being eaten. 2. Artificial incubation of fertilized eggs Using fertilized yellow eel eggs for artificial incubation is a good way to cultivate yellow eel seedlings. In the peak season of yellow eel spawning in summer, after the rice fields are fertilized, weeded, and the rice seedlings are closed, you can look for yellow eel eggs in the large ditches of the rice fields, the still water around the weirs of the dikes with a lot of grass, and the still water of the ditches. As long as you see a pile of foam in the field or pond, it is the hatching nest of the yellow eel, and the eggs are in it. You can use a ladle or a large bowl to gently scoop up the eggs and the pond foam, put them in a bucket with fresh water, and carry them back home. Place the captured fertilized eggs in a basin, water tank or large tile basin for still water incubation, keep the water temperature between 25℃ and 30℃, and keep the water fresh. Generally, young eels can be hatched in about 7 days. At this time, some loofah tendons can be placed in the basin to provide a sheltered place for the new young eels. In the first few days after the young eels emerge from the membrane, they use their own yolk as nutrition and do not need to be fed. When the yolk sac is about to disappear, about 7 days later, you can use boiled egg yolk to mix it into liquid and pour it into the basin for feeding. The stocking density should not be too large. As the young eels continue to grow, they can be dispersed and raised. They cannot eat large particles of food. When feeding, feed them in small amounts and multiple times, and do not overfeed. When the young eels grow to more than 10 cm, you can boil and chop the earthworms and feed them.

2. Are eel eggs hatched internally or externally?

It is understood that the reproductive season of the yellow eel is about June to August. In its individual development, it has the characteristics of male and female reversal, that is, it is female from the embryonic stage to the first sexual maturity (that is, the gonads of individuals with a body length of less than 35 cm are all ovaries); after spawning, the ovaries gradually become testes; when the body length is 36-48 cm, the sex is partially reversed, and the male and female individuals are almost equal; those that grow to more than 53 cm are mostly testes. When the young fish can only grow to 20 cm, the female fish will reach maturity after 2 winters, with a body length of at least 34 cm. The largest individual can reach 70 cm and weigh 1.5 kg. The yellow eel lays eggs near the entrance of its burrow. Before spawning, it spits foam from its mouth to form a nest. The fertilized eggs develop on the water surface in the foam with the help of the buoyancy of the foam. Both male and female fish have the habit of protecting the nest.

3. How do good reproduce?

The breeding technology of yellow eel

1. Natural reproduction

When artificially breeding eels, we can strengthen feeding management and create an ecological condition that is suitable for eel reproduction to achieve the goal of self-reproduction of eels. The main measures are:

(1) Build a breeding pond or separate a section of the rearing pond for breeding. A smaller juvenile eel protection pond should be built in the breeding pond. Leave more round or rectangular holes on the pond wall and separate the holes from the breeding pond with fine-mesh wire mesh. Water can flow through the mesh and the juvenile eels can enter the protection pond, but male and female eels cannot enter, in order to protect the juvenile eels.

(2) Place 3 to 4 eels (mostly female) with a body length of 25 to 30 cm per square meter in the breeding pond. Regardless of gender, all eels must be yellow and strong, and they must be carefully managed 1 to 2 months before breeding and fed with high-quality animal bait such as earthworms and maggots.

(3) To simulate the spawning environment of rice field eels, build earth ridges around the breeding pond (at a certain distance from the pond wall) and in the middle. The ridges should be about 20 cm wide and 10 to 15 cm above the water surface. Some weeds should be planted on the ridges.

(4) During the spawning period of yellow eels, the environment should be kept quiet. The water in the breeding pool should be kept in good quality through fine water flow or constant seepage. The incoming water should first pass through the young eel protection pool, and then slowly flow into the breeding pool. The stimulation of the slow flow can induce the young eels to swim upstream and enter the protection pool.

(5) Place some soft, thick things such as loofah tendons and willow roots in the breeding and protection ponds to provide shelter and shelter for the eel fry and to facilitate their collection and transplantation.

(6) Yellow eels lay eggs in batches, and the spawning period lasts for a long time. After the breeding season of the year is over, the parent eels can be caught in cages and raised or processed separately to prevent the young eels from being eaten.

2. Artificial incubation of fertilized eggs

It is a good idea to use fertilized eel eggs to artificially cultivate eel seedlings. In the peak season of eel spawning in summer, after the rice seedling fields are fertilized, weeded, and the rice seedlings are closed, eel eggs can be found in the large ditches of the rice fields, the still water around the weirs of the dikes with a lot of grass, and the still water of the ditches. As long as you see a pile of foam in the fields and ponds, it is the eel's hatching nest with eggs in it. You can use a scoop or a large bowl to gently pick up the eggs and the pool foam, put them in a bucket with fresh water, and transport them home. Put the captured fertilized eggs in a basin, water tank or large tile basin for still water incubation, keep the water temperature between 25℃ and 30℃, and keep the water fresh. Generally, young eel seedlings can be hatched in about 7 days. At this time, you can put some loofah tendons in the basin to provide a sheltered place for the new young eels. In the first few days after the young eels emerge from the membrane, they use their own yolk for nutrition and do not need to eat. When the yolk sac is about to disappear, about 7 days later, you can use the boiled egg yolk to mash into liquid and pour it into the basin for feeding. The stocking density should not be too large. As the young eels grow up, they can be raised in a dispersed manner. They cannot eat large particles of food. When feeding, feed them in small amounts and multiple times. Do not overfeed. When the young eels grow to more than 10 cm, you can cook and chop the earthworms and feed them.