Science Fair Project Encyclopedia
Sericulture
Sericulture is the rearing of silkworms for the production of raw silk. Although there are several commercial species of silkworms, Bombyx mori is the most widely used and intensively studied. According to Chinese records, the discovery of silk production from B. mori occurred about 2,700 B.C Today, China and Japan are the two main producers, together manufacturing more than 50% of the world production each year.
Production
Silkworm larvae are fed cut-up mulberry leaves and after the fourth molt climb a twig placed near them and spin their silken cocoons. The silk is a continuous-filament fiber consisting of fibroin protein secreted from two salivary glands in the head of each larvae, and a gum called sericin , which cements the two filaments together. The sericin is removed by placing the cocoons in hot water and this frees silk filaments ready for reeling. The immersion in hot water also kills the silkworm larva. Single filaments are combined to form yarn. This yarn is drawn under tension through several guides and wound onto reels. Finally, the yarn is dried, and the now raw silk is packed according to quality.
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