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Monday, August 6, 2012

Silkworm and Silk Production in Afghanistan

Two Afghans overseeing the demonstration of
silk production for the research center in Balkh
Province. The have to keep the temperature
and humidity in the proper range for good
Afghanistan has a long history in the national and international silk production and silk carpet markets. Balkh and Kunduz provinces were major silk producers in the North of Afghanistan 30 years ago. During the years of conflict, the production level of silk cocoons decreased because producers of silk products were unable to continue their business, so there was less demand for cocoons and silk thread. Although much of the know-how still remains, it takes a push-and-pull action to encourage farmers to start silkworm propagation and to get back into home-industry making silk products. Traditional farmers are concerned that they cannot develop this market alone. 
Thank you, Wikipedia, for this information. http://en.wikipedia.org/wiki/Sericulture 
Sericulture, or silk farming, 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. Sericulture has become one of the most important cottage industries in a number of countries like China, Japan, India, Korea, Brazil, Russia, Italy and France. Today, China and India are the two main producers, together manufacturing more than 60% of the world production each year.
Not any old mulberry leaves is good enough. There are
different types of mulberries so one of the tests going
on here is to find out which of the mulberries is best for
commercial production. When they first hatch the worms
must be given mulberry leaves that are finely chopped.
Sikworm larvae are fed mulberry leaves, and, after the fourth moult, climb a twig placed near them and spin their silken cocoons. This process is achieved by the worm through a dense fluid secreted from its gland structural glands, resulting in the fibre of the cocoon. The silk is a continuous-filament fiber consisting of fibroin protein, secreted from two salivary glands in the head of each larva, and a gum called sericin, which cements the two filaments together. The sericin is removed by placing the cocoons in hot water, which frees the silk filaments and readies them for reeling. The immersion in hot water also kills the silkworm pupae. This is known as the degumming process.

Single filaments are combined to form thread. This thread is drawn under tension through several guides and wound onto reels. The threads may be plied together to form yarn. After drying the raw silk is packed according to quality.

Here the silkworms are old enough to start spinning silk
pretty soon. Now they can handle whole mulberry leaves
The stages of production are as follows:
·       The silk moth lays eggs.

·       they feed mulberry leaves.

·       When the silkworms are about 10,000 times heavier than when they hatched.
·       They are now ready to spin a silk cocoon.

·       The silk is produced in two glands in the silkworm's head and then forced out in liquid form through openings called spinnerets.

·       The silk solidifies when it comes in contact with the air.
·       The silkworm spins approximately 1 mile of filament and completely encloses itself in a cocoon in about two or three days but due to quality restrictions, the amount of usable silk in each cocoon is small. As a result, 5500 silkworms are required to produce 1 kg of silk.
·       The silk is obtained from the undamaged cocoons by brushing the cocoon to find the outside end of the filament.

·       The silk filaments are then wound on a reel. One cocoon contains approximately 1,000 yards of silk filament. The silk at this stage is known as raw silk. One thread consists of up to 48 individual silk filaments.

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