How many days can a silkworm live?
Silkworm is a completely metamorphosed insect, which has to go through four stages of development with completely different morphology and physiological functions: egg, larva, pupa and adult. Eggs are the stage of embryogenesis and development to form larvae, larvae are the growth stage of feeding, pupae are the metamorphosis stage of the transition from larvae to adults, and adults are the reproductive stage of mating and spawning to reproduce offspring. The whole generation only eats in the larval stage, storing nutrients for the life activities of pupae and adults.
Silkworm life is divided into four stages: birth, growth, development, reproduction and death. This is the life cycle of a silkworm.
1. Silkworm egg incubation: After 8-9 days of incubation, young silkworms are hatched from silkworm eggs. The newly emerged silkworms are black and small, commonly known as ant silkworms.
2. First instar: The color of the first instar silkworm changes from black to dark brown. After eating mulberry for 3-4 days, the appetite is not large. The first molting will be carried out after entering the sleep period, and the sleep period is 8~ 12 hours.
3. Second instar: The silkworm body grows obviously and its color becomes lighter. The mulberry feeding time is about 3 days, and the sleep period is 8~ 12 hours.
4. Third instar: The color of the silkworm turns light brown, the food intake begins to increase, and it enters the sleep period in about 4 days. 1~3-year-old silkworms are generally called young silkworms, and enter the big silkworm stage after 10~ 14 hours.
5. Fourth instar: The silkworms entering the big silkworm stage develop rapidly and their food intake increases obviously. The fourth instar generally lasts for 5 days, and the sleep period is very long, generally called the big sleep period, and the sleep period can reach 30 to 40 hours.
6.5-year-old: The mulberry leaves eat the most, accounting for more than 75% of the total leaves in about 7 days. After 7 days, the silkworm body began to become shorter and brighter, commonly known as adult silkworm. When the mature silkworm stops eating, it begins to spin silk and form cocoons.
The growth process of silkworm will go through incubation, growth, spinning, cocoon formation and cocoon breaking. Silkworms reproduce with eggs, which are like fine sesame seeds, about 1 mm wide and about 0.5 mm thick. When the temperature rises, silkworm eggs begin to develop. After 7- 15 days, the silkworm eggs become transparent and the outline inside can be seen, which means that the silkworm baby is coming out. Silkworms that have just hatched from eggs are covered with fine hairs, also called ant silkworms.
Silkworms feed on mulberry leaves. After eating mulberry leaves continuously, the body turned white and began to peel after a period of time. Once peeled off, it is a second-instar larva. Even if you lose your skin once, you will gain one year. It will shed its skin four times in total, and when it becomes a fifth instar larva, it will start spinning and cocooning. When the silkworm's back is shiny and yellow, it means spinning and cocooning. It takes two days to form a complete cocoon and molt into pupa for the last time in the cocoon. About ten days later, it appeared in the form of a silkworm moth and came out of the cocoon.