There are many animals that bear a thick coat of hair on their body. Such animals generally live in cold climates. Thick coat of hair over the body of such animals traps lot of air and keeps them warm as air is a bad conductor of heat. It prevents the warmth of the body from escaping and also prevents the coldness of the surroundings from entering. Thus, thick layer of hair over their body protects them from harsh cold. For example: Sheep, Goat, Camel, Yak, etc.
Fleece and Wool bearing animals; like sheep, goat, camel, yak, etc. bear two types of hair – coarse hair and fine-soft under hair. Fine soft hair is found close to the skin in such animals. The fine soft under hair is called fleece. Fiber for wool is obtained from the fleece (hair) of such animals and hence such animals are called wool bearing animals.
Many breeds of sheep are found in India. Sheep gives milk and meat; in addition to wool, but are reared mainly to obtain wool in different parts of the world.
Angora wool is obtained from Angora Goats. Angora Goats are found in hilly regions, such as Jammu and Kashmir. Pashmina wool is obtained from Pashmina Goats. Yak wool is obtained commonly in Tibet and Laddakh. Alpaca and Llama are other animals that give wool.
Selective breeding and rearing of sheep: Some breeds of sheep bear only a coat of fine hair. Such animals are reared by selective breeding. Selective breeding is the process to obtain animals or plants having special characteristics.
In India, sheep are reared generally in the sates of Jammu and Kashmir, Himachal Pradesh, Uttaranchal, Arunachal Pradesh and Sikkim, or the plains of Haryana, Punjab, Rajasthan and Gujarat.
Food of sheep: Sheep are herbivores and feed generally on grass and leaves. Apart from grass and leaves they also feed on corn and oil cakes. Oil cakes are materials left after obtaining of oil from oil seeds.
Process to obtain wool from sheep: Steps given below are followed to obtain wool from sheep or other wool bearing animals:
Step 1: Shearing: The fleece (hair) of sheep is shaved off along with a thin layer of skin. In olden days this was done using pair of metal blades. But now-a-days machine is used to cut off the fleece. This is similar to shaving of beards or hair. This process is called shearing.
Shearing is generally done in summer so that sheep could get new hair by winter to get protection against cold.
Step 2: Scouring: Fleece, after shearing, is washed properly to remove dirt and grease. The washing of fleece; after shearing; is called scouring.
Step 3: Sorting: After scouring, fleece is sorted according to texture. This process is called sorting.
Step 4: After sorting, fluffy fibers; called burr; are picked out from hair. Burr is the fiber that gives wool.
Step 5: Dyeing: After sorting and picking out of burrs, these are dyed in desired colors.
Step 6: Spinning: The fibers are then straightened, combed and rolled into yarns.
Wool yarn is used in knitting sweaters and woolen cloths, i.e. fabric.