How to Handle Silkworms After They Spin Cocoons? Key Management Points Silkworm Farmers Must Know
The silkworm is an insect of the family Bombycidae in the order Lepidoptera, and is the main raw material source for silk. It holds an important place in human economic life and cultural history. In South China and Taiwan, China, it is commonly called "silkworm baby" or "niangzai." When it grows to a certain stage, it spins a cocoon, and the cocoon is woven from a single thread 300-900 meters long. Let's take a look below at how to handle silkworms after they spin cocoons!
Why can silkworms spin cocoons?
The silkworm's spinning and cocoon-making are related to the silk gland organs in its body. From the perspective of the silkworm's growth process, during the larval stage, after eating a large amount of mulberry leaves, the silkworm digests and absorbs the nutrients in the mulberry leaves. Then, the various amino acids in the mulberry leaves are absorbed and stored by the silk glands in the silkworm's body. As the silkworm's age increases, the silk glands also grow larger, and the expansion rate is especially rapid during the fifth instar. Before spinning the cocoon, from the external appearance one can see that the silkworm's chest area is slightly transparent, precisely because of the large amount of protein accumulated in the silk glands.
Why do silkworms spin cocoons?
Physiologically speaking, since the proteins that make up the silk glands are composed of amino acids, if there are too many amino acids in the silkworm's body, the silkworm will be poisoned, so the silkworm needs to expel amino acids by spinning silk to achieve the purpose of detoxification. Under natural conditions, as a holometabolous insect, the silkworm is fragile at every stage of life, especially at the pupal stage, when it is most fragile. It stops feeding, loses mobility, and is very easily harmed by natural enemies. The silkworm evolved the behavior of spinning silk to make a cocoon, enclosing itself in a dense cocoon shell. In this way, it can both avoid natural enemies and protect itself, and safely transform into a pupa inside the cocoon, and allow the organs inside the pupa to transform into the form of a silkworm moth, finally emerging as an adult silkworm moth.
What should be done after silkworms spin cocoons?
After the silkworm finishes spinning its cocoon, it will molt and pupate inside the cocoon, emerge after 8-10 days, mate and lay eggs, and then die naturally after about a week. Therefore, after the silkworms spin cocoons, you can spread a sheet of white paper on the bottom of a clean cardboard box without peculiar smells, and also hang a layer of white paper around the sides (do not glue it firmly). Place the cocoons in the box, and the emerging silkworm moths will mate, while the female moths lay eggs on the paper. In silk production, if the pupae are allowed to metamorphose into adults and naturally dissolve the cocoon and drill out, then because the cocoon is broken with a hole, the silk thread will become shorter and cannot be used for spinning and weaving silk, so before they break out of the cocoons, the cocoons should be placed in boiling water to kill the silkworm pupae and make the cocoons easy to unwind.