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Not to be confused with Bombyx mandarina

Bombyx mori is also known as the domestic silk moth or the mulberry worm is a species of the order Lepidoptera from the family of Bombicidae from the genus


Bombyx. Their larva are primarily responsible for the production of silk and is therefore known as silkworm the process of extraction of silk from their cocoons is known as Sericulture.Silk moths have a wingspan of 3–5 cm (1.2–2.0 in)

Morphology[]

Bombyx mori has a fluffy-hair fringed body and small silver-veined wings they also posses a pair of hair-fringed comb-like antennae. Their antennae are one of the key features used to describe them. The color of their bodies and wings is pure milky white color other than their antenna and eyes. it spread to India, Korea, Nepal, Japan, and the West. The domestic silk moth was domesticated from the wild silk moth Bombyx mandarina, which has a range from northern India to northern China, Korea, Japan, and the far eastern regions of Russia. The domestic silk moth derives from Chinese rather than Japanese or Korean stock. the practice of breeding silkworms for the production of raw silk, has been under way for at least 5,000 years in China, It is an economically important insect, being a primary producer of silk. A silkworm's preferred food are white mulberry leaves, though they may eat other mulberry species and even the orange. Domestic silk moths are entirely dependent on humans for reproduction, as a result of millennia of selective breeding. Wild silk moths (other species of Bombyx) are not as commercially viable in the production of textile.

Metamorphosis[]

Eggs take about an approximate of 13 days (Almost 2 weeks) to hatch into silkworm, that have a constant habit of feeding continuously. They have a high preference for mulberry, As their second name suggests that is, the mulberry worm. However they aren't monophagous (Prefer only one kind of food) since they can eat other species of mulberries, as well as some other wild berry bushes, mostly oranges. . When the color of their heads eventually becomes darker, it is an indication that they have outgrown their own bodies. After molting, the larval phase of the silkworms emerge as a white worm. After they have molted four to five times, their bodies become slightly tinted with a light shade of yellow. The larvae then cling onto a surface ready to enter their secondary pupal stage (Semi-adult) , and enclose themselves in a cocoon made up of the silk produced by the silk glands of the caterpillar. The final molt from larva to pupa takes place inside the cocoon, which provides a vital layer of protection to the vulnerable pupal stage preventing it from being exposed to the dangerous world full of hungry predators. Many other Lepidopterans produce cocoons namely moths however only Bombyx mori and Bombyx mandarina and a few notable other species carry out the entire process using fabrics and textile materials. If the animal is allowed to survive after spinning its cocoon and through the pupal phase of its lifecycle, it releases a highly corrosive enzymes... enzymes to penetrate through the cocoon by creating a hole inside it in the cocoon so it can emerge as an adult Bombyx mori. The corrosive enzymes are only corrosive to the silk which decreases the value of the silk greatly therefore silkworms are boiled and killed in some countries where Sericulture is carried out, the silkworms upon being destroyed are killed.

the adult phase of the lifecycle in which unfortunately is not capable of a purely well functioning flight, in a comparative degree to the wild B. mandarina and other Bombyx species, whose males fly to meet females and for evasion from predators. Some may emerge with the ability to lift off and stay airborne, but sustained flight cannot be achieved. This is because their bodies are too big and heavy for their small wings. Females are about two to three times bulkier and heavier than males as they are carrying the eggs but have similarl colorations. Adult Bombycidae have reduced and un-developed mouthparts and do not feed like several moth species.

Sericulture[]

he cocoon is made of a thread of raw silk from 300 to about 900 m (1,000 to 3,000 ft) long. The fibers are very fine and lustrous, about 10 μm (0.0004 in) in diameter. About 2,000 to 3,000 cocoons are required to make 1 pound of silk (0.4 kg). At least 70 million pounds (32 million kg) of raw silk are produced each year, requiring nearly 10 billion cocoons. The domestic species B. mori, compared to the wild species (e.g., B. mandarina), has increased cocoon size, body size, growth rate, and efficiency of its digestion. It has gained tolerance to human presence and handling, and also to living in crowded conditions. The domestic silk moths cannot fly, so the males need human assistance in finding a mate, and it lacks fear of potential predators. The native color pigments have also been lost, so the domestic silk moths are leucitic, since camouflage is not useful when they only live in captivity. These changes have made B. mori entirely dependent upon humans for survival, and it does not exist in the wild. The eggs are kept in incubators to aid in their hatching. Silkworms were first domesticated in China over 5,000 years ago. Since then, the silk production capacity of the species has increased nearly tenfold. The silkworm is one of the few organisms wherein the principles of genetics and breeding were applied to harvest maximum output. It is second only to maize in exploiting the principles of heterosis and crossbreeding. Silkworm breeding is aimed at the overall improvement of silkworms from a commercial point of view. The major objectives are improving fecundity (the egg-laying capacity of a breed), the health of larvae, quantity of cocoon and silk production, and disease resistance. Healthy larvae lead to a healthy cocoon crop. Health is dependent on factors such as better pupation rate, fewer dead larvae in the montage, shorter larval duration (this lessens the chance of infection) and bluish-tinged fifth-instar larvae (which are healthier than the reddish-brown ones). Quantity of cocoon and silk produced are directly related to the pupation rate and larval weight. Healthier larvae have greater pupation rates and cocoon weights. Quality of cocoon and silk depends on a number of factors, including genetics.


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