CATDOLL : CATDOLL: The appearance of silkworms at different stages of growth (pictures of the appearance of silkworms at different stages of growth)

1. What are the five stages of silkworm growth?

Sericulture is generally divided into five processes, namely silkworm eggs, silkworm ants, mature silkworms, silk cocoons and silkworm moths.

The outer layer of the silkworm egg is a hard eggshell, and the inner layer is yolk and serosal membrane; the ant silkworm is hatched from the silkworm egg, with many fine hairs, very small, and looks a bit like an ant; the mature silkworm is the larvae that have developed to the last stage, gradually stop eating mulberry, and the silkworm body shrinks and becomes slightly transparent; the silkworm cocoon is the cocoon of the silkworm, the sac-shaped protective layer of the silkworm pupae; the silkworm moth is formed in the cocoon, shaped like a butterfly

2. What are the growth changes of silkworms?

From the time the silkworms hatch, measure and observe their growth and changes and record them

1. The little silkworms that hatch from the eggs are called "ant silkworms". They are dark black, like ants, and can only eat some tender mulberry leaves. After about a week, they will shed a layer of skin, and the color will turn light black, and their bodies will grow a little bigger. After about 10 days, the silkworms will shed another layer of skin, and the color will turn grayish white.

Their bodies grew bigger, and when they ate the mulberry leaves together, the sound made was like the "rustling" sound of rain. After about a week, they would shed another layer of skin and grow plump and white. After another week, they stopped eating the mulberry leaves, and their bodies became transparent, like strips of white jade. They began to spit out crystal clear filaments from their mouths, which kept wrapping around themselves.

Before you know it, a bright white cocoon is made. About a month later, a silk moth breaks out of the cocoon and lays countless sesame-sized eggs nearby. After a while, these eggs will hatch into countless baby silkworms.

2. The hatching of silkworm eggs requires suitable temperature and humidity.

3. Molting is a significant feature of the silkworm's growth process. The silkworm's body changes every time it molts. Silkworms molt 4 times in the larval stage and 2 times in the pupal stage (inside the cocoon), for a total of 6 molts in their lifetime.

4. Molting is a significant feature of the silkworm's growth process. The silkworm's body changes every time it molts. Silkworms molt 4 times in the larval stage and 2 times in the pupal stage (inside the cocoon), for a total of 6 molts in their lifetime.

3. What is the growth process of silkworms?

The growth process of silkworms is divided into four stages: eggs, larvae, cocoons, and adults.

Silkworm eggs are transparent in the early stages and black in the later stages. The newly hatched larvae are black and feed on young mulberry leaves. The later larvae turn white and feed on old mulberry leaves. The fifth-instar larvae will spin silk cocoons and break out of the cocoons after ten days to become adults.

1. Silkworm eggs

The first stage of silkworm growth is the silkworm egg. The silkworm egg is round and small in size. The newly laid silkworm egg is transparent. At this time, wrap the silkworm egg in a paper towel. After a period of time, the silkworm egg will turn black and the larvae will hatch.

2. Larvae

The second stage of silkworm growth is larvae. The newly hatched larvae are black and covered with fine hairs. At this time, they need to be provided with fresh mulberry leaves to supplement their nutrition. After a week, the silkworms will turn white and begin to shed their skin. A larvae must shed its skin four times in total before it can grow to maturity.

3. Cocoon

The third stage of silkworm growth is cocooning. After four moltings, the silkworms are fifth-instar larvae. At this time, the larvae have the ability to spin silk and make cocoons. They will climb to the corners of the breeding box or the artificially provided area to spin silk and wrap themselves in it.

4. Adult

The fourth stage of silkworm growth is adult. After the cocoon is made, wait for ten days for the silkworm pupa to break out and become an adult. At this time, cover the container with a net to prevent the adult from flying away. After waiting for a day, the adult will mate on its own, lay silkworm eggs, and wait to die.

4. Introduction to the four stages of a silkworm’s life?

The life cycle of a silkworm consists of four stages: egg, larva, pupa and adult.

Silkworm eggs:

Silkworms reproduce by laying eggs. Silkworm eggs look like fine sesame seeds, about 1 mm wide and 0.5 mm thick. A female moth can lay 400 to 500 silkworm eggs. 1700 to 2000 silkworm eggs weigh about 1 gram and have a diameter of 0.2 cm. The color of silkworm eggs is light yellow or yellow when they are first laid, and changes to light red bean color or red bean color after 1 to 2 days, and then turns to gray-green or purple after 3 to 4 days. It no longer changes and is called a fixed color.

The outer layer of the silkworm egg is a hard eggshell, and inside is yolk and serous membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into a silkworm. It crawls out of the eggshell, and the eggshell becomes white or light yellow after it is empty.

The first instar is four to five days; the second instar is three to four days; the third instar is four days; the fourth instar is six days; the fifth instar is seven to nine days; the pupal stage is fourteen to eighteen days; and the moth stage is three to five days.

larva:

When the silkworm hatches from the egg, its body is brown or black, very small, and covered with fine hairs, and it looks a bit like an ant, so it is called ant silkworm. The ant silkworm is about 2 mm long and 0.5 mm wide. After it crawls out of the egg shell, it will eat mulberry leaves after 2 to 3 hours.

silkworm chrysalis:

After the silkworms spin cocoons on the cocoon nest, they will turn into pupae after about 4 days. The body shape of the silkworm pupa is like a spindle, with three body sections: head, thorax and abdomen. The head is very small, with compound eyes and antennae; the thorax has thoracic legs and wings; the bulging abdomen has 9 body segments. Professional workers can distinguish the sex of silkworms from the lines and brown dots on the abdomen of the silkworm pupa. When the silkworms first pupate, their body color is light yellow and the pupa body is tender and soft. Gradually, it will turn into yellow, yellow-brown or brown, and the pupa skin will also harden. After about 12 to 15 days, when the pupa body begins to soften again and the pupa skin is a little wrinkled and earthy brown, it will turn into a moth.

5. How many stages are there in the life of a silkworm?

The silkworm goes through four different stages in its life: egg, larva, pupa and adult.

Silkworms hibernate as eggs and hatch into larvae when mulberry trees sprout in spring. The larvae feed on mulberry trees and grow, then go into hibernation and molt after 4 days and begin to spin cocoons after about 25 days.

After two days, the silk is spun and the silkworms shed their skins and pupate in the cocoon after another 2-3 days. After about 10 days, the pupae become adults, which are silkworm moths. Male and female moths mate and lay eggs, and then die. In order to meet the production requirements of raising silkworms multiple times a year, the silkworm seed farm adjusts the incubation period of silkworm eggs through various technical measures such as staggered seed production seasons, cold storage of silkworm seeds, and hydrochloric acid impregnation, so that silkworm seeds can be supplied in different seasons in spring, summer and autumn. When the silkworms are dormant, they do not eat or move. On the surface, they are sleeping, but in fact they are molting, that is, they are shedding their old skins and putting on new ones in order to continue to grow. The silkworms that have just shed their skins are called awake silkworms, which means they wake up after sleeping. The larval stage of silkworms is based on dormancy and is divided into five instars. The larvae that have just hatched from silkworm eggs are called first-instar silkworms. After eating mulberry leaves for about 3 days, they start to sleep for about 1 day. After waking up from the first sleep, they are second-instar silkworms. After about two and a half days of the second instar, they start to sleep for about 1 day. After the second sleep, they are third-instar silkworms. The third instar lasts about 3.5 days, and the silkworm begins to sleep for about 1 day. The fourth instar lasts about 4 days, and the silkworm begins to sleep for about two days. After the fourth sleep, the silkworm becomes the fifth instar. The fifth instar lasts about 6-8 days. Before the cocoon is formed, the silkworm stops eating mulberry leaves, and the body shrinks and becomes translucent, which is called mature silkworm. The silkworms from the first to the third instar are usually called young silkworms, and the silkworms from the fourth and fifth instars are called adult silkworms.

6. What is the growth process of silkworms?

The growth process of silkworms is divided into four stages: egg, larvae, pupa and adult. 1. The silkworms hatch. The silkworms that have just hatched from the eggs are black and are called "ant silkworms". They are covered with fine hairs, which will no longer be obvious after about two days.

2. The silkworm grows up. The silkworm feeds on mulberry leaves. After eating mulberry leaves continuously, its body turns white. After a period of time, it begins to shed its skin. The molting period lasts for about a day. It does not eat or move like sleeping. This is called "hibernation".

3. After the silkworm has shed its skin once, it is the second-instar larva. It will age one year after each molting, and it will molt four times in total before it becomes the fifth-instar larva and starts to spin silk and make cocoons.

4. It takes a five-year-old silkworm larva two days and two nights to make a cocoon, and it sheds its skin for the last time in the cocoon to become a pupa.

5. About ten days after the silkworm breaks out of the cocoon, it emerges as a silk moth and breaks out of the cocoon.

After emerging from the cocoon, the female moth emits a smell from its tail to attract the male for mating. The male dies after mating. The female moth can lay about 500 eggs in about one night, and then slowly dies.

7. What are the 8 growth stages of silkworms?

1. Incubation

The silkworms that have just hatched from eggs are called ant silkworms. They are covered with fine hairs, which will become less noticeable after about two days.

Silkworms live on mulberry leaves. After eating mulberry leaves continuously, their bodies turn white. After a period of time, they begin to shed their skin. 3. Silkworms do not eat or move when they sleep. On the surface, they are sleeping, but in fact, they are shedding their old skin and replacing it with a new one to continue growing. Silkworms shed their skin 4 times during the entire breeding process. Each time they shed their skin, they do not eat or move. At this time, try not to disturb them, and do not throw them away thinking they are sick. Each sleep period of silkworms lasts about one day. 3. Silkworms spin silk

4. After molting once, it is the second instar larva. Each molt is counted as one year older. It takes four molts in total to become the fifth instar larva before it starts spinning silk and making cocoons.

Generally, the silkworms start to spin cocoons around 25 days old. When the silkworms' backs are shiny, yellow and transparent, it means that they are about to spin silk and spin cocoons. At this time, a cross-space should be provided for the silkworms to spin cocoons. 6. It takes two days to form a complete cocoon, and the silkworms complete the last molting in the cocoon and become pupae. 7. Break out of the cocoon

After about ten days, the female moth emerges from its cocoon and becomes a silkworm moth. After emerging from its cocoon, the female moth emits a scent from its tail to attract the male moth to mate. After mating, the male dies. The female moth can lay about 500 eggs in one night and then slowly dies.

8. How many stages are there in the life of a silkworm? What are the characteristics of each stage?

The following introduces the morphology of silkworm eggs, silkworm pupae, silkworm moths and the growth characteristics of silkworms.

Silkworm eggs: Silkworms reproduce by laying eggs. Silkworm eggs look like fine sesame seeds, about 1 mm wide and 0.5 mm thick. A female moth can lay 400-500 silkworm eggs, 1700-2000 silkworm eggs, weighing about 1 gram. The color of silkworm eggs is light yellow or yellow when they are just laid, and turns into light red bean color or red bean color after 1-2 days, and then turns into gray-green or purple after 3-4 days. It will no longer change, which is called fixed color. The outer layer of silkworm eggs is a hard eggshell, and inside is yolk and serosal membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into an ant silkworm. It crawls out of the eggshell, and the eggshell becomes white or light yellow after it is empty.

Ant silkworm: When the silkworm hatches from the egg, its body is brown or reddish brown, very small, and has many fine hairs, which looks a bit like an ant, so it is called an ant silkworm. The ant silkworm is about 2 mm long and 0.5 mm wide. After it crawls out of the egg shell, it will eat mulberry leaves after 2 to 3 hours.

The sleeping nature of silkworms: Silkworms eat a lot of mulberry, so they grow very fast and their body color gradually fades. But their appetite gradually decreases or even completely stops eating. They spit out a small amount of silk, fix their abdomen and feet on the silkworm seat, raise their head and chest, and stop moving, as if they are asleep. This is called "sleeping". The sleeping silkworms may seem motionless on the outside, but they are preparing to shed their skin inside. After shedding the old skin, the silkworms enter a new age. From ant silkworms to spinning silk cocoons, they shed their skin four times in total. Having the sleep nature is one of the growth characteristics of silkworms. Sleep nature is a genetic trait of silkworms and is also affected by the environment. The silkworms currently raised in my country belong to the four-sleeping varieties.

Silkworm age: also known as age period, which indicates the development stage of the silkworm. From the ant silkworm to the first molt is the first age; after waking up from sleep, it enters the second age; after molting again, it enters the third age; after the third molt, it enters the fourth age, and the fourth molt is also called the long sleep. After the long sleep, it enters the fifth age. The fifth-age silkworm grows very fast, with a body length of 6 to 7 cm and a weight of about 10,000 times the weight of the ant silkworm.

Mature silkworms: When silkworms reach the end of the fifth instar, they gradually show the characteristics of maturity: first, the feces they excrete change from hard to soft, and from dark green to leaf green; their appetite decreases, and the amount of food they eat decreases; the front digestive tract is empty, and the chest becomes transparent; then they stop eating completely, their bodies shorten, and their abdomens tend to be transparent; their head and chest are raised, they spit out silk threads from their mouths, and they swing left and right and up and down to find a place to build their cocoons. Such silkworms are called mature silkworms.

Cocooning during the adult stage: People put mature silkworms in special containers or on cocoons, and the silkworms will spin silk and make cocoons.

Cocooning can be divided into four processes: 1. The mature silkworms first spit out silk, which is bonded to the cocooning device, and then spit out silk to connect the surrounding cocoon branches to form a cocooning support, that is, a cocooning net. The cocooning net does not have a cocoon shape, but is just some soft and messy cocoon silk layers to serve as a support for cocooning. 2. After the silkworms make a cocooning net, they continue to spit out messy silk circles to thicken the inner layer of the cocoon net, and then spit out silk in an S-shaped manner, and the outline of the cocoon begins to appear, which is called a cocooning coat. The silk fibers of the cocoon coat are fine and brittle, arranged very irregularly, and have a high content of sericin. 3. After the cocoon coat is formed, the cocoon cavity gradually becomes smaller, and the front and rear ends of the silkworm body bend back to form a "C" shape. The silkworm continues to spit out cocoon silk, and the spinning method changes from S shape to ∞ shape, which begins the process of forming a cocoon layer. 4. When the silkworm's body is greatly reduced due to a large amount of silk spinning, the swing speed of the head and thorax slows down, and there is no certain rhythm. The spinning begins to appear messy, forming a loose and soft cocoon silk layer, called a pupa lining.

Silkworm pupa: After the silkworms make cocoons on the cocoon nest, they will turn into pupae about 4 days later. The body of the silkworm pupa is shaped like a spindle, with three body sections: head, thorax, and abdomen. The head is very small, with compound eyes and antennae; the thorax has thoracic legs and wings; the bulging abdomen has 9 body segments. Professional workers can distinguish the sex of silkworm pupa from the lines and brown dots on the abdomen. When the silkworm just turns into a pupae, its body color is light yellow, and the pupa body is tender and soft. Gradually, it will turn into yellow, yellow-brown or brown, and the pupa skin will also harden. After about 12 to 15 days, when the pupa body begins to soften again and the pupa skin is a little wrinkled and earthy brown, it will turn into a moth.

Silkworm moth (adult): Silkworm moths are shaped like butterflies, with white scales all over their bodies, but because their two pairs of wings are small, they have lost the ability to fly. The head of the silkworm moth is spherical, with bulging compound eyes and antennae; the chest has three pairs of thoracic legs and two pairs of wings; the abdomen has no ventral legs, and the terminal body segment has evolved into external genitalia. The female moth is large and crawls slowly; the male moth is small and crawls faster, with its wings vibrating rapidly, looking for a mate. Generally, the female moth can lay fertilized eggs 3 to 4 hours after mating. The male dies after mating, and the female moth can lay about 500 eggs in one night, and then slowly dies.

The silkworm lays eggs, hatches into silkworms, turns into pupae, and then turns into moths, completing the cycle of a new generation. This is the life history of the silkworm.