Source of animal fibres - Class 7 PDF Download

There are natural and artificial fibre.Natural fibres are those who are obtained from plants and animals and artificial are those who are made from industries (man-made).Animal fibres are wool and silk.
Wool
Wool is obtained the fleece of sheep, goat ,rabbit, camel,yak and other animals.These animals have fine and soft hair.sheep is main source of animal for obtaining wool. The best quality of wool is obtained from the shoulders and sides of the sheep.The process of selectively choosing parents and rearing to produce offspring with special characters is termed as 'selective breeding'.

Animals that yield wool
Sheep, yak,cashmere goat, angora goat, angora rabbit,camel,Llama and Alpaca.

Wool processing
Shearing: This is the first in wool processing. The fleece or fur along with a thin layer of top dead skin is removed from the body of the sheep by shearing.

Grading: wool fibre is graded according to it's length, texture and colour.

Scouring and drying: The sheared fur is thoroughly washed to remove grease, dust,dirt and sweat residue which gather in the wool.After scouring the washed fibre is passed for drying.

Dyeing: The fibres are dyed in different colors as the natural colours of fleece is white, black or brown.

Carding: The fiber are straighten and then combed to form narrow rope like sheets.

Spinning: The sheets of narrow roped are spun to form Yarn.

Weaving or knitting: weaving is done by criss- crossing two sets of yarns whereas knitting involves only one set of yarn.

Now you can understand that wool takes a long journey to get the fabric.by this time the sheep is ready to be sheared again.

History of the wool
Wool was probably the first animal fibre to be made into cloth.The art of spinning wool into yarn was developed in 4000BC.The major wool producers in the world are Australia,China,South Africa and Argentina.

Silk
Silk is a animal fibre made up of protein.It is produced from silkworms.The rearing of silkworm to produce silk is called sericulture.

Life cycle of a silk moth
Stage 1: The female silk moth lays hundreds of eggs at a time 
Stage2:The larvae called caterpillar or silkworm hatch from the eggs.
Stage3:The caterpillar completely cover itself by a cocoon made of silk fibre.It turns into a pupa inside the cocoon.
Stage4:The pupa grows into an adult moth inside the cocoon.

Cocoon to silk 
Boiling:Cocoons are collected and kept under sun or boiled in water.This separates the silk fibres and kills the pupae inside the cocoon.
Reeling: Special machines are used to unwind the fibres of silk from Cocoons.
Spinning:The silk fibre is then spun into silk threads.

Synthetic fibres
Synthetic fibres are made in industries (man-made). These are not produce from plants or animals.Synthetic fibres are cheaper than natural fibres.Nylon,polyster, acrylic.