How to raise silkworms well in summer and autumn? These ten points are key

For silkworms, I think everyone is still very familiar with them. Silkworm rearing has a history of several thousand years from ancient times to the present. As early as ancient times in our country, people already planted mulberries and raised silkworms, so in the process of raising silkworms, attention must be paid to certain rearing techniques and skills.

Ten points let you raise silkworms well in summer and autumn

1. Prevent pesticide poisoning. During the silkworm rearing season, do not spray organochlorine pesticides such as bisultap on farmland near the silkworm room; their fumigation effect will cause silkworms to be poisoned; mulberry leaves fed to silkworms must be confirmed non-toxic through trial feeding before leaves can be picked to feed the silkworms.  

2. Mosquito coils or mosquito-killing and insect-killing agents are prohibited in the silkworm room. If used in houses adjacent to the silkworm room, the doors and windows of the silkworm room must also be closed to prevent silkworm poisoning.  

3. The silkworm room should be fitted with screen doors and screen windows to prevent flies from entering the silkworm room and harming the silkworms, and add “silkworm fly killer” emulsion or spray it on the silkworm body to kill fly maggots.  

4. Before rearing silkworms, block mouse holes, keep a certain distance between the silkworm racks and the walls, and scatter lime powder or silkworm medicine around the feet of the silkworm racks to prevent mice from climbing up. For rearing silkworms on the ground, do a good job of chemical rodent control.  

5. Summer and autumn silkworm rearing has higher temperatures, so doors and windows should be opened to strengthen indoor ventilation and air exchange. Spraying mulberry leaves with clean water and using an electric fan indoors to blow a gentle breeze also help lower the indoor temperature.  

6. Diseased silkworms found should be cleaned up promptly and put into a disinfection basin containing bleaching powder solution or lime slurry. It is prohibited to feed diseased silkworms to livestock and poultry, so as to prevent the spread of pathogens and pollution of the environment.  

7. Silkworm excrement contains a large amount of pathogenic matter. Do not spread it out to dry around the silkworm room; it should be concentrated in the field for composting or put into a manure pit for composting, to prevent the spread of pathogens.  

8. Summer and autumn have high temperatures, and pathogens reproduce quickly. Pay attention to picking leaves as needed, transporting leaves promptly, and storing leaves reasonably. The mulberry storage pool should be disinfected once in each instar, and do not feed overnight mulberry leaves.  

9. In high-temperature and high-humidity weather, avoid feeding wet leaves. Do not sprinkle water on stored mulberry leaves. Remove excrement frequently and scatter more fresh lime powder, dry straw and other materials to inhibit the breeding and reproduction of pathogens.  

10. Outside the silkworm rearing season, do not store grain, bran and other items in the silkworm room, so as to avoid dampness producing mites that harm silkworms during silkworm rearing.

Preparatory work before silkworm rearing  

1. Planting mulberries: The silkworm feeds on mulberry leaves, so mulberry trees must be planted well before silkworm rearing. For mulberry planting techniques, please read the article "Mulberry Planting Technique Video"; the editor will not repeat them here.  

2. Silkworm room: Raising one batch of silkworms requires a large silkworm room of 20 square meters, a small silkworm room of 10 square meters, and a dedicated leaf storage room, etc., to help prevent disease.  

3. Silkworm tools: including thermometers, silkworm trays, plastic film, silkworm nets, square cluster mounts, silkworm chopsticks, goose feathers, mulberry cutting knives, chopping boards, mulberry scissors, black cloth, etc. Raising one batch of silkworms requires 16 to 20 silkworm trays, 160 to 200 square cluster mounts, and 14 small silkworm nets.  

4. Disinfection of silkworm room and silkworm tools: 7 days before silkworm rearing, after cleaning the silkworm room and silkworm tools, spray disinfect with disinfectant essence or 1% bleaching powder or strong chlorine essence solution, using half a jin of medicinal liquid per square meter. After spraying, close doors and windows and seal for more than 24 hours. At the same time, the surrounding environment of the silkworm room should also be sprayed for disinfection.

Rearing methods for large silkworms  

1. Rearing management: 4th to 5th instar silkworms are called large silkworms, with an optimum temperature of 25°C and a wet-dry difference of 3°C. Usually after the fifth instar silkworms are fed the second leaf after resuming feeding, the silkworms are moved to the ground. Before moving the silkworms to the ground, first clean and wash the ground, disinfect it with bleaching powder, and after it dries, scatter a layer of lime powder on the ground, then move the silkworms to the ground. Rearing large silkworms requires good ventilation and strengthened disinfection. Disinfect the silkworm body and silkworm seat once daily with lime powder (before feeding mulberry leaves). When picking leaves, do not pick yellow leaves, muddy leaves, soot-covered leaves, or insect-bitten leaves.  

2. Maturity characteristics: Large silkworms have a large appetite, so they must be given good mulberry leaves and fed to satiety. One batch of silkworm eggs uses 500 kg of leaves. Fifth instar large silkworms begin to mature after 6 to 7 days. The characteristics of mature silkworms are: stopping feeding on mulberry leaves, discharging a large amount of green soft excrement, transparent chest, body slightly soft and shortened, appearing waxy yellow; the head swings left and right. This is the suitable time for mounting on the cluster.  

3. Mounting method: The mounting method for square cluster mounts is to choose 4 to 5 square cluster mounts, alternately overlap them and place them horizontally, then evenly scatter the mature silkworms onto the cluster. After the silkworms have crawled into place, hang the cluster up by hooks. During the mounting period, maintain good ventilation. Generally, after spring silkworms are mounted, cocoons can be harvested and sold after six days, and after summer and autumn silkworms are mounted, after 4 to 5 days.

Rearing techniques for mature silkworms  

When silkworm babies reach the end of the fifth instar, they gradually show the characteristics of maturity: first, the excrement discharged changes from hard to soft, and from dark green to leaf green; appetite declines, and the amount of mulberry eaten decreases; the front part of the digestive tract is empty, and the chest appears transparent; then they completely stop eating, the body shortens, and the abdomen also tends toward transparency. The head and chest of the silkworm body are raised, the mouth emits silk threads, and it swings left and right, up and down, searching for a place to spin a cocoon. Such silkworms are called mature silkworms. People place mature silkworms in specially made containers or on cluster mounts, and the silkworms then spin silk and form cocoons. Cocoon formation can be divided into four processes:  

1. The mature silkworm first spits out silk and bonds it to the cluster mount, then spits silk to connect the surrounding cluster branches, forming a cocoon-forming support, namely the cocoon net. The cocoon net does not have a cocoon shape; it is only some loose and messy layers of cocoon silk, serving as the support for cocoon formation.  

2. After the silkworm forms the cocoon net, it continues to spit out messy silk loops, thickening the inner layer of the cocoon net, and then spits silk in an S-shaped manner, beginning to show the outline of the cocoon, called the cocoon floss. The silk fibers of the cocoon floss are fine and brittle, arranged very irregularly, and also have a high sericin content.  

3. After the cocoon floss is formed, the cocoon cavity gradually becomes smaller. The front and rear ends of the silkworm body bend toward the dorsal side, forming a “C” shape. The silkworm continues to spit out cocoon silk, and the silk-spinning method changes from S-shaped to ∞-shaped. This begins the process of forming the cocoon layer.  

4. When the silkworm, due to spitting out a large amount of silk, has its body greatly shrunk, the swinging speed of the head and chest slows down, and there is no certain rhythm. Silk spinning begins to appear messy, forming a loose and soft layer of cocoon silk, called the pupal lining.

From the above analysis, we can know that there are still many silkworm rearing techniques. Silkworm raisers should not blindly rear silkworms. They should communicate and exchange more with successful raisers, learn from each other's experience and methods, and strive to take fewer detours.