Tuesday, 3 March 2015

sericulture and pisciculture

Sericulture:Sericulture, or silk farming, is the rearing of silkworms for the production of silk. Although there are several commercial species of silkworms,Bombyx mori is the most widely used and intensively studied silkworm. Silk was first produced in China as early as the Neolithic period. Sericulture has become an important cottage industries in countries such as BrazilChinaFranceIndiaItalyJapan, Korea, and Russia. Today, China and India are the two main producers, with more than 60% of the world's annual production.
Silkworm larvae are fed with 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 structural glands, resulting in the fiber of the cocoon. The silk is a continuous filament comprising fibroin protein, secreted from two salivary glands in the head of each larva, and a gum called sericin, which cements the filaments. The sericin is removed by placing the cocoons in hot water, which frees the silk filaments and readies them for reeling. This is known as the degumming process. The immersion in hot water also kills the silkworm pupae.
Single filaments are combined to form thread, which is drawn under tension through several guides and wound onto reels. The threads may be plied to form yarn. After drying, the raw silk is packed according to quality.

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Pisciculture:Fish farming or pisciculture is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery. Worldwide, the most important fish species used in fish farming are carpsalmontilapia and catfish.


There is an increasing demand for fish and fish protein, which has resulted in widespread overfishing in wild fisheries, China holding 62 percent of the world's fish farming practice. Fish farming offers fish marketers another source. However, farmingcarnivorous fish, such as salmon, does not always reduce pressure on wild fisheries, since carnivorous farmed fish are usually fed fishmeal and fish oil extracted from wild forage fish. The global returns for fish farming recorded by the FAO in 2008 totalled 33.8 million tonnes worth about $US 60 billion. In 2005, aquaculture represented 40% of the 157.5 million tons of seafood that was produced, meaning that it has become a critical part of our world's food source even though the industry is still technically in its 'infancy' and didn't really become well known until the 1970s. Because of this rise in aquaculture, there has been a rise in the per capita availability of seafood globally within the last few decades.

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I have personally talked with my parents about this topic.I have learnt a lot about silk worm and a lot about indoor fisheries.I also have learnt all this from the non-profitable website known famously as Wikipedia and also from famous knowledge books such as Ask Me Everything,etc.



                                                                  By-Kuhoo Paranjape. 

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