DOMESTICATION AND IMPROVEMENT OF ANIMALS
The rearing of animals for specific purposes is called domestication, and such animals are called domestic animals. Domestication of animals started during the ‘hunting and gathering phase’ of human civilization. Man domesticates a variety of animals for food transport agricultural operation, wool, fur, study, research and pleasure. Cow, buffaloes, goats, sheep and pigs for meat and honey bee for honey. Cattles, horses, mules, donkeys, camels, elephants and reindeer are used for transport. The domesticated animals play an important role in the economy of rural India. The first animals to be domesticated may have been the dog and goat. The various breeds of domestic animals we use today have evolved from wild ancestors through selective breeding. Pets, livestock, poultry, Fishery, Sericulture, apiculture and Lac culture are briefly discussed in this chapter. The branch of agriculture specializing in the breeding raising care and utilization of domestic animals is known as animal husbandry.
Dogs and Cats
Dogs and cats are the closest pets of man. They are carnivores turned omnivores. They occurs wild in various parts of the world.
(1) Dogs : Dog was among the earliest animals domesticated by man. A large number of breeds have been produced by intensive inbreeding and artificial selection of a single ancestral dog species. These vary in form colour, size and fur. It has proved to be a faithful companion and guard of its master. The domestic dog, canis familiars, is found in almost all countries. It is useful in many ways.
(i) It can be trained to protect flocks (sheep or goat) and herds (cattle).
(ii) It is helpful in tracking and running down the game such as hare and fox.
(iii) It is a very useful animal for hunting.
(iv) Some breeds, which have sharp sense of smell and sight, are employed to trace the criminals drug peddlers and prowleres.
(v) It can lead the blind persons.
(vi) Eskimos use dogs to pull sledges (wheel less vehicles used over snow or ice).
(vii) Dog raising is a profitable business. Pedigree dogs fetch high return.
(viii) Dog is a symbol of loyalty.
(2) Cats : Cat (Felis domesticus) is a small, furry mammal. It has many breeds. It is domesticated to eradicated rats and mice. It is also a nice pet.
Livestock
Meaning of livestock : The word livestock refers to the domestic animals kept or dealt in for use or profit. It includes cattle, buffaloes, sheep, goats, pigs, horses, mules, donkeys and camels. The most important of these are cattle and buffaloes.
Cattle (Bos indicus), Buffaloes (Bos bubalus) : The word cattle includes cow (adult female), bull (uncastrated adult male), bullock or OX (castrated adult male) and steer (young castrated male).
Importance of cattle and Buffaloes : Cattle and buffalo are most important forms of domesticated animals. They are next to land in use for farmers. They are widely used for :
(1) Agricultural Operations : Cattle are used in agricultural operations such as ploughing, harrowing and levelling land; in harvesting and thrashing ripe crops; and in working wells, etc.
(2) Milk : Cows and buffaloes provide milk, an important human food with all the essential materials.
(3) Transport : Cattle are employed in cart driving to transport men and materials. However, they are being fast replaced by machines.
(4) Manure and fuel : The dung provided by them acts as a valuable manure for maintaining the fertility of the soil. It is also used for preparation of biogas or gobar gas. Dung cakes provide cheap fuel to the poor, but the fields get deprived of an important manure.
(5) Leather : Hides obtained from these animals are used for the preparation of leather goods.
(6) Glue and gelatin : Their bones, horns and hoofs yield glue and gelatin.
(7) Meat : Beef and buffalo meat are eaten by certain people
(8) Hair : Hair are used for making brushes.
(9) Hybridisation : Indian bulls are used for
Breeds of cattle : There are 26 breeds of cattle and 7 breeds of buffaloes in India. They differ in colour, general body build, form of horns, forehead and geographical distribution. The best cattle breeds occur in the drier regions of the country. The most important breeds of milk cows in the United States of America are Holstein-Friesian, Jersey, Quernsey, Ayrshire and Brown Swiss. Depending upon the utility, the cattle are classified into the following groups;
(1) Milch breeds that give good milk-producing cows,
(2) Draught breeds which give good working bullocks,
(3) General utility (dual-purpose) breeds the females of these breeds are good milk-producers and the bullocks are good draught animals.
Table : 10.3-1 Some Breeds of Indian Cattle
S.No. | Milch Breeds | Distribution |
1. | Gir | Gujrat, Rajasthan |
2. | Sahiwal | Punjab, Haryana, Uttar Pradesh |
3. | Red Sindhi | Andhra Pradesh |
4. | Deoni | Andhra Pradesh |
Drought Breeds | ||
1. | Malvi | Rajasthan, Madhya Pradesh |
2. | Nageri | Delhi, Haryana, Uttar Pradesh |
3. | Hallikar | Karnataka |
4. | Kangayam | Tamil Nadu and other parts of South India |
General Utility Breeds | ||
1. | Haryana | Haryana, Punjab, Bihar, Madhya Pradesh, Gujrat |
2. | Ongole | Andhra Pradesh |
3. | Kankrej | Gujrat |
4. | Tharparkar | Andhra Pradesh, Gujrat |
Table : 10.3-2 Some Breeds of Indians Buffaloes
S.No. | Name | Distributon |
1. | Murrah | Punjab, Haryana, Uttar Pradesh |
2. | Bhadawari | Uttar Pradesh, Madhya Pradesh |
3. | Jaffrabadi | Gujrat |
4. | Surti | Rajasthan, Gujrat |
5. | Mehsana | Gujrat |
6. | Nagpuri or Ellichpuri | Central and South India |
7. | Nili Ravi | Punjab, Haryana |
Feeding of cattle : The cattle feed consists of two components (1) Roughage (2) Concentrates.
(1) Roughage : Roughage includes fodder, silage, hay and straw. They have a large amount of fibre contents and low nutritive value.
(2) Consentrates : The concentrates used in the cattle feed is a mixture of substance which are rich in nutrient contents. Cotton seeds, oil seeds, oil cakes, cereal grains like bajra, gram, rice polish, etc. are some important substances included in the concentrates in the cattle feed. In the winter season, cattle are given green feeder, mainly berseem and lucerns. In other seasons, cattle are given maize, bajra, jowar and dry fodder.
Cattle should be given sufficient water daily. Suckling calves also need water.
Breeding of Cattle : Cattle breeders select and mate best type of cattle for a particular purpose. The breeding of cattle is done by two methods i.e. natural and artificial.
(1) Natural breeding : It is further of two types i.e. random and controlled
(i) Random breeding : Here some pedigree bulls are kept along with the grazing cows. Bulls not selected for breeding are castrated and changed to bullocks.
(ii) Controlled breeding : In this type of breeding native cows are crossed with superior quality of imported bulls in natural breeding. Foreign dairy breeds like Jersey (England), Holstein Freisian (Holland), Brown Swiss (Switzerland), Ayrshire (Scotland) have been imported to give better results.
(2) Artificial breeding : The introduction of semen (sperm) in the body (vagina) of females by artificial means is called artificial insemination. This method is comparatively better and economical. Several cows can be inseminated by semen of a single bull.
(3) Superovulation and Embryo transplantation : This is a recent technique that has been introduced in India to produce super milch cows.
Breeding and Calving Season : In India the breeding season commences from September and continues upto February, and the calving season from July to November. During this breeding period, the bulls have been found to be very active sexually and the quality and quantity of semen are very high, particularly during winter (November to February). The buffaloes show the maximum of ovarian activity and the largest percentage of them conceive during this period.
Length of Gestation : The length of gestation of buffaloes varies, influenced by breed and environment, between 276 and 340 days, but on an average, it lasts for 307 days or 10 months, in contrast to the cow with an average gestation of 284 days or 9 months.
(i) Duration of lactation, Dry period and interval between calving : In milch buffaloes, the average period of lactation is 281 days, a dry period of 139 days and an interval between calving of 420 days is normal. This means that, on the average, a buffalo/cow produces a calf at 14 months intervals.
(ii) Important livestock diseases : Just like human beings, livestocks like cow, buffalo, etc. Suffer from various diseases. The diseases in livestock are mainly caused by the attack of micro-organisms like virus, bacteria or fungi, or by an attack of worm parasites. Some important livestock diseases are as follows.
(1) Viral diseases : Foot and mouth diseases, pox.
(2) Bacterial diseases : Rinderpest, tuberculosis, anthrax.
(3) Fungal diseases : Ringworm.
Sheep and Goats
There are many breeds of sheep (ovis aries) and goats (Capra hircus) in our country. Today sheep are raised in all parts of the world. Sheep provide us with wool, skin and mutton and goats provide us with milk, meat, skin and hair. The fine soft wool called pashmina is the underfur of Kashmir and Tibet goats. A sheep lives for about 13 years.
Feeding of sheep and goats : Sheep feed on green tender grass or weeds or other herbage. Goats feed on a variety of trees by browsing on the buds and foraging on a variety of plants. Oil cakes and mineral mixture are also fed to keep sheep in good condition.
Breeding of sheep and Goats : To improve the quality of a sheep, cross-breeding experiments are usually done. For this purpose, a good quality wool yielding or mutton producing sheep is chosen and cross breed with exotic breeds like Dorset, Horn and Merino. About 19% of world goat population occurs in India. These differ in body build, colour, horn size, ear size, hair texture, etc. The wild goat, Capra hircus, of Baluchistan and shind is the ancestral stock of all the breeds of domestic goat.
Table : 10.3-3 Some breeds of Indian Sheep
S.No. | Breed | Distribution | Use |
1. | Lohi | Punjab, Rajasthan | Good quality wool, milk |
2. | Rampur-Bushair | Uttar Pradesh, Himachal Pradesh | Brown coloured fleece for superior cloth |
3. | Nali | Haryana, Punjab, Rajasthan | Superior-carpet wool |
4. | Bhakarwal | Jammu and Kashmir | Under-coat used for high quality woollen shawls |
5. | Deccani | Karnataka | Mutton, no wool |
6. | Nellore | Maharashtra | Mutton, no wool |
7. | Marwari | Gujrat | Coarse wool |
8. | Patanwadi | Gujrat | Wool for army hosiery |
Table : 10.3-4 Important Breeds of Indian Goats
S.No. | Name | Distribution |
1. | Gaddi and Chamba | Himachal Pradesh |
2. | Kashmiri and Pashmina | Himachal pradesh, Kashmir, Tibet |
3. | Jamunapari | Uttar Pradesh, Madhya Pradesh |
4. | Beetal | Punjab |
5. | Marwari | Rajasthan |
6. | Berari | Maharashtra |
7. | Malabari | Kerala |
8. | Bengal | Bihar, Orissa |
Shearing of wool : The shearing of wool is essential to promote the health of sheep. The removal of hairs (wool) from the sheep is done very carefully in the mild weather. The recommended periods for shearing of wool are winter (February- March) and rainy (August-September) seasons when rich grazing ground is available. The sheep are washed properly before the removal of hairs.
The manufacture of wool from sheep hairs is a complicated process consisting of cleaning, drying, bleaching, dyeing, spining and twisting.
Common diseases of sheep and goats
(1) Sheeps : These include haemorrhagic septicaemia, anthrax, sheep-pox and black-quarter. The common signs of illness are high temperature, cessation of rumination, hard breathing, coughing, sneezing, diarrhoea and drooping gait. The sheep also suffer from external and internal parasites.
Timely inoculation prevents the diseases.
(2) Goats : The goats are less prone to serious diseases. They suffer from some contagious diseases such as anthrax, goat pox, pleuropneumonia and foot and mouth disease. The general signs of illness are as in the cows. Parasitic infection is common in goats.
Pig
Pig, also called hog or swine, is an omnivorous, nonruminant, gregarious mammal of genus Sus. All breeds of pigs have descended from the European wild boar sus scrofa or a crossbreed of this and the Asiatic species, S. indicus. The care and management of pigs is called piggery.
Pigs are the most prolific breeders and quick growers among the domestic animals. A group of 10 sows (Female hog) and one boar may produce over 160 piglets in a year. Pigs are most useful domestic animals, especially of lower classes of society. They are most economical source of meat and animal fat. Pig meat, in general, is known as pork and the meat obtained from different parts of the body have been given different names, for example bacon obtained from the back and sides and ham from the back of the thigh.
Feeding of pigs : Indigenous pigs survive through scavenging on kitchen wastes and farm by products and human faeces. Pig keepers raise them on grass, straw roots and grains. As they can feed on human faeces, they serve as secondary host for tape worms.
Breeds and breeding of pigs : Pig breeding has now started on commercial scale. The improved exotic types, number of which is insignificant is maintained mostly at all the seven Regional Pig Breeding stations of the country. Some breeds of the pigs are given in table.
Table : 10.3-5 Important Breeds of Pigs
Breeds | Distribution |
Native Pigs | |
1. Desi | Uttar Pradesh, Bihar, Punjab, Madhya Pradesh |
2. Ghori | Manipur, Assam, Meghalaya, Arunachal Pradesh |
Exotic pigs | |
1. Berkshire | U.K. |
2. Large White Yorkshire | U.K. |
3. Landrace | Switzerland, Denmark |
All India Co-ordinated research project : The ICAR initiated an All India Co-ordinated research projects on pigs during the fourth five year plan. The project started functioning early in 1971. The main objective of the projects is to develop suitable breeds using imported stock. The centres where this project is in operation are :
(1) Indian Veterinary Research Institute, Izatnager
(2) Assam Agricultural University, Khanapara,
(3) Andhra Pradesh Agricultural University, Tirupathi
(4) Jawaharlal Nehru Krishi Viswa Vidyalaya, Jabalpur.
Diseases of Pigs : These include swine fever, foot and mouth, swine-pox, swine-plague, anthrax, tuberculosis, infectious dysentery and piglet influenza. General signs of illness are as in sheep and goats.
Horses
Distinguishing Features : The horses (Equus cabalus) are solid- hoofed, non-ruminant quadrupeds with long, pendant mane and tail bearing long hair all over. They are intelligent animals. They learn fast are faithful pets and can adapt to all sorts of climatic conditions. It was the first beast of burden. Polo is game played on horse back.
Feeding : Horses are fed on oats, barley, gram and hay. Common salt is also added to their diet. Green grass may also be given if available.
Breeding : If compared to other animals, horses have a low reproductive rate. Controlled natural mating in horses has been in practice in India for a long time. A high professional skill is required for rearing, training and medical care of race horses.
Table : 10.3-6 Important breeds of Indian Horses
S.No. | Name | Regions |
1. | Kathiawari | Rajasthan and Gujrat |
2 | Marwari | Rajasthan |
3. | Bhutia | Punjab and Bhutan |
4. | Manipuri | North-eastern mountains |
5. | Spiti | Himachal Pradesh |
6. | Zanskari | Ladakh |
Donkeys
Distinguishing Features : Donkeys (Equus asinus) are smaller than horses but have larger head, longer pinnae and narrower hoofs. Their mane is erect and tail has a tuft of hair at the tip.
Feeding : The donkeys mainly feed on straw and fodder. They are often let free to graze on the roadside.
Breeding : There are two breeds of donkeys in our country : small, dark grey and large, light grey to almost white. The grey donkey occurs in most parts of the country. The white donkey, also called wild ass, occurs in Rann of Kutch. Donkeys have descended from the wild ass Equus asinus of Abyssinia.
Mule
Mule is the hybrid between male ass (jack) and female horse (mare). It has the stamina of ass and size of horse, but is sterile. Similarly, the cross between male horse (stallion) and female ass is called hinny.
Mules are known for their toughness. Since they are sexually sterile, they have to be produce every time a new.
Feeding : They are fed mainly on green fodder, crushed grams and barley. They are also given salt.
Breeding : Indian army has imported male donkeys from Europe for breeding mules. Army uses two type of mules : (a) General service type and (b) Mountain artillery type. The latter are firm footed and can carry heavy loads on steep terrain.
Common Disease of Equines : The horses, donkeys and mules suffer from many diseases. They include pink eye or influenza, strangles, tetanus, colic etc.
Camels
The camel is a large, horn less, ruminant mammal of genus Camelus. It is popularly called “the ship of the desert” because of its great travelling power in a desert. It is a valuable beast of burden in hot desert and semidesert regions as it can live on minimum food and water when travelling with load.
Types of camels : There are two types of camels :
(1) Arabian camels (Camelus dromidarius) : With a single hump, short hair and found in north Africa to India. It does not occur in wild form.
(2) Turkish or bactrian camel (Camelus bactrianus) : With two humps, long hair and found in Gobi desert of central Asia. It occurs in wild form also.
Feeding : Camels are fed on dry fodder (barley, straw) supplemented with chopped green fodder made of pulses, mustard and green pees. They browse on trees, shrubs and bushes. The size of the hump is a good indicator of its health.
Breeding : There are four kinds of camels in India. These are Jaisalmeri, Sindhi and Bikaneri found in Rajasthan and Kutchi found in Gujrat. They have a well-defined breeding season. Camels breed in winter (November to March).
Diseases : Camels suffer diseases such as anthrax, pneumonia, camel-pox and surra.
Elephant
Elephants are chiefly found in forests with tall trees where bamboo’s grow in profusion. They have very poor sight but sense of hearing and smell is highly developed.
Feeding : Daily food intake is considerable, but only partially digested and utilization is low. Natural food includes bamboo shoots, leaves and various fruits. Working elephant are fed straw, hay and crushed grain as a supplement.
Breeding : Puberty occurs at between 8 and 12 years. The gestation period is 21 – 22 months. The calving interval is 4 years. Elephants may live for up to 90-100 years. Elephants are of two types : African elephants and Indian elephants.
Table : 10.3-7 Differences between Indian Elephant and African Elephant
S.No. | Indian elephant (Elephas maximus) | African elephant (Laxodonta africana) | |
1. | Physical Features | Small ears, High domed forehead with 2 prominance on top of skull. One process on trunk tip Convex backed. Tusks in males only, not always | Large ears convex sloping forehead. |
2. | Mature at | 25 years | 25 years |
3. | Weight at maturity | Male 3000 kg | Male 6000 kg |
4. | Geographical distribution | Ceylon, India, Burma, Thailand, Vietnam, Laos, Malaysia, Indonesia | East, Central and West Africa |
5. | Uses | Timber extraction and log moving in forested areas | Very limited. In small area of Zaire, used for timber transport. |
Yak
Yak (Poephagus grunniens) is found in Tibet, Ladakh, Lahaul, Spiti, Garhwal and Sikkim. It gives meat, hide and wool. Yak is also used for tilling land. The transport of people and goods in these regions would be impossible without this animal.
Sericulture
Sericulture is the breeding and management of silk worms for the production of silk. It has been practiced in India since second era or century B.C. The silk which is produced by silk worm is of a valuable natural protein fibre. Silk worms are the larvae of silk moths. The rearing of silk worm for the production of silk is known as sericulture.
History of silk : Historical account of use of silk and rearing of silk worm eggs, larvae and cocoons are available from china. It was Lotzu the empress kwang-Ti who for the first time discovered the silk thread and its source the silk worm cocoon. The technique of sericulture was kept as a secret by the chines people. In about 550 B.C. The sericulture technique was diffused to European countries. The available mythological literature deals with facts rearing the use of silk in ancient India. By about 1000 A.D. the sericulture was in practice in China, Europe and India, China was the leading country in this field.
At present the sericulture is practiced in China, Japan, Korea, India, Brazil, Russia, France and Italy. Some of the south east asian countries. China is topmost country producing some 48% cocoons and 40.9% of raw silk. Next biggest silk producing country is Japan, India is placed in third position as for as the production of silk in term in quantity is concerned.
Silk in India : As far as silk as a fabric is concerned it is a matchless fabric second to none. Therefore, silk garments have been a favourite choice since ancient times. Use of silk clothes finds its mention from pre-historic period. There are description of use of silk clothes from vedic period. In Ramayana and Mahabharat period the silk clothes adored the bodies of royal princess, prince, kings and queens. It attire of the rich people. The silk clothes were used to the superiority of social and economic status. It was given in gifts by rich people and royal families.
In the medieval period the silk was a recognised commodity of commerce. The silk clothes and raw silk were imported from China and Japan. Later on it was also imported from Europe. By the Moghul period India had a rich heritage of silk clothes. The silk was imported as raw silk. It was spun into silk thread and silk clothes were woven in handlooms silk clothes became almost a craze among royal families and rich persons. A number of such looms were in operation in Banaras, and different parts of Uttar Pradesh, Kashmir became centres for the production of cocoons and rearing of silk worm. Sporadic silk textile centres were also present in South India. It was in 1905-1906 that a scientific investigation in the field of sericulture was undertaken in India by the Indian Institute of Agricultural Research at Pusa, New Delhi. It was Lefroy who conducted research on the silk worm and potentialities of silk production in India. A series of exhibitions were organised to popularize silk and attract the attention of scientists and industrialists as well towards sericulture in India.
By 1910 India started regular production of raw silk. The rearing of Bombyx mori and Autheraea species was undertaken. Silk textile industry was finally established in Kashmir, U.P. and Karnataka. Silk garments were exported by this time. Silk clothes from Bengal, Banaras and karnataka were famous even in the European markets.
Silk in Modern Age : Sericulture as well as silk industry is firmly established in India. India at present is the third biggest country in the field of silk production and only next after China and Japan.
The reasons for the poor growth of sericulture in India were:
(1) High cost of production.
(2) Low yield.
(3) Poor quality of raw silk.
But the recent efforts by the Government of India and various state governments such as research in sericulture and training in sericulture technique, development of silk worms marketing facilities and cultivation of plants, e.g. Morus indica or shahtoot Norus alba or ‘Toot’ castor sal etc. Central Sericulture Station, Berhampore, Central Research and Training Centre, Mysore and Ranchi have been established. Various states have undertaken a programs of research, training and plantation of host plants under their rural development programs. As a result of these efforts new varieties of mulberry plants have been developed and are being cultivated. These varieties are called as M 2 and M5 varieties. They gave 100% increased yield of mulberry leaves upon which the silk worm feeds.
Different varieties of silk worm, Bombyx mori and Autherea have been developed which can be cultivated in various states. Existing races of silk worm are being improved Bivoltine species are being developed. Low production and higher yield have been achieved as a result of these efforts. India is producing 4200 metric tons of silk per annum (1980). This figure is even higher at present. India is exporting some 25% to 30% of its total silk production in the form of silk garments and fabrics. Karnataka is the biggest silk producing state followed by Jammu & Kashmir and Tamil Nadu, Madhya Pradesh is also emerging on the scene of silk production. India is producing China silk, Tasar silk or Cosa silk, Muga silk and Eri silk today.
Systemic position
Phylum – Arthropoda
Class – Insecta
Order – Lepidoptera
Family – Bombicidae and satarnidae
Family – Bombicidae
(1) Bombyx mori : It is known as China silk worm or mulberry silk worm. It is native of China. It has been fully domesticated for the production of silk. It produced quality of silk which is white silk or yellow silk.
(2) Other species of Bombyx are B. texior, B. fortunatax and B. meridionles. They are well Known in our country.
Family – Saturnidae : Antheraea paphio – It belong to the family saturnidae. It is widely distributed in india in the states of Karnataka, Tamilnadu, Madhya Pradesh, Uttar Pradesh, Bihar and West bengal. It feed on and fig plants. Its favourite host plant is Arjun (Terminalia arjuna), sol (shorea robusta). It has been recently domesticated for sericulture. It produced Tassar silk (kosa silk.)
Habit and habitat : The silk worm distributed in temperate regions are diapause type i.e. they remain inactive for some time in winter. The silk worms inhabiting some tropical regions.
Adult Moth : The moth measures about 25 mm in length and wing span measures about 40-50 mm in width. Female moths are larger than male moths. In general univoltine races are of larger size that multivoltine.
It has whitish colour with gray marks on wings in some races. The body is divisible into head, thorax and abdomen. Head contains a pair of eyes and a pair of pectinated antennae specially larger in males. Thorax contains three pairs of legs and two pairs of wings covered with scales. Female moths are without mouth. The abdomen is plump. Digestive system is poorly developed. The excretory system consists of three pairs of malpighian tubules present at the end of mid gut. The reproductive system is very well developed in females and males.
Life History
(1) Copulation : The copulation lasts for about three hours. During copulation the male sits over the female and holds her with the help of chitinous hooks. Both the moths acquire back to back’ position. The female has a scent gland at the terminal end of the abdomen, which secretes volatile secretion called pheromones to attract the male.
(2) Egg : Copulation is immediately followed by egg laying. The eggs are small, oval and creamy white in colour. They become darker as they become older. Each moth lays about 300 to 500 eggs. The eggs are glued to the under-surface of the leaves of the host plant.
(3) Larva : After hatching a larva comes out of egg. It is called as caterpillar larva. It is 1.2 mm to 3 mm in length depending upon the race. It has grey or creamy-white colour.
The body of larva is divided into head, thorax and abdomen. The head consists of three fused segments. Mouth parts are biting and chewing type or strongly mandibulate. A pair of antennae and six pairs of are also present on head. Mandibulate mouth parts are used to cut and chew the leaves. The thorax consists of three segments. Each segment contains a pair of legs with recurved hooks. They are used for locomotion and manipulation of food during feeding. The abdomen consists of ten segments. The last and tenth segment is poorly developed. Five pairs of pseudo legs are present on 3rd, 4th, 5th , 6th and 9th abdominal segments. These are used for locomotion.
- Silk gland : Among other visceral organs larva contains well-developed paired glands called silk glands. When fully developed, these glands becomes five time larger than the length of the larva and there weight becomes 2/5th of the total body weight. Its secretion probably lubricates the silk. The silk is secreted in liquid form, which solidifies on coming in contact with air.
The larva is voracious eater. It feeds on mulberry leaves. It may ingest about 30,000 times more than its body weight during its complete larval period and increases about 10,000 times more than the body weight of its body from the time of hatching. As the larva grows, it sheds it cuticle. This is called as moulting. The form of larva between two successive moults is called as instar. The larva has five instars:
Ist instar – from hatching to Ist moult
IInd instar – between Ist moult and IInd moult
IIIrd instar – between IInd moult and IIIrd moult
IVth instar – between IIIrd moult and fifth moult
Vth instar – between fifth moult and pupation
A fully-grown larva of Vth instar attains the length of 7.5 cm. It stops feeding and starts spinning the cocoon. It secretes silk thread from its spinneret and forms covering in which it encloses itself completely. It takes about 3-4 days to spin the cocoon.
(4) Pupa : The cocoon consists of silk thread. The enclosed immobile larva in the cocoon is called as Pupa. The pupal stage is non- feeding and non-mobile. It remain & inactive.
(5) Cocoon : The cocoon is white or yellow in colour. It is made up of about 1000-1200 meters long silk thread. The thread is wound around the cocoon is concentric circles. The weight of one cocoon is about 1.8 to 2.2 gms. The pupal period lasts for about 10 to 12 days. Alkaline fluid which makes the threads of cocoon to be soft. Soft threads are cut open by the imago. A young moth comes out of cocoon.
- (6) Fertilization : After the moths emerge out from cocoons one female from one lot is kept with the male from another lot. They form pair and copulate. After copulation is over separated and kept with female of another Thus one male can be used to fertilize at the most two females of different lots.
(7) Egg laying : After fertilization the female starts laying eggs. Egg laying is completed in about 24 hours. The laid eggs are called seeds. The eggs are transferred in sterilized and tray stored at 4°C.
Factors influencing the life cycle : The life cycle is influenced by the external environmental factors, such as, temperature, humidity and light. These factors control the growth of the larvae and also the quality of silk produced. The growth and moulting is controlled by hormones called juvenile hormone and ecdysone.
Composition of silk : The silk is a secretory product of silk glands of the larva. Silk is composed of proteins. It consists of an inner part made up of fibroin protein (C30 H46 N10 O12) and is covered with an outer envelope made up of sericin protein (C30 H40 N10 O12). The silk thread contains 75-80% fibroin and 20-25% of sericin,
Sericulture industry : Sericulture industry involves three steps,
(1) Mulberry cultivation : Mulberry is the only food of silkworms. Mulberry plants come up in any soil and in any climate. It is propagated by cuttings. The land is ploughed well 6 or 7 times in April-May and manured at the rate of 2 to 25 tons per hectare. Small pits are scooped out 2 or 3 cuttings are lanted in pit. Each cutting should be 20 to 23 cm in length with nodes. When the plants grow too high they are cut back and this is known as pruning.
Pruning : Pruning will help in the production of a new flush of leaves. The plants can yield for 12 years. Every year 6 to 8 crops of leaves can obtained and the average yield per hectare is 25 to 30 metric tons of green leaves.
(2) Silk worm rearing – Silk worm rearing needs the following:
(i) Rearing house
(ii) Rearing trays and stands
(iii) Chandrikes as support to build the cocoon.
The hybrid eggs are obtained from the sericulture department. The larvae are hatched from the eggs. The newly hatched larvae are brushed into rearing trays and tender, chopped are provided to them. At the end of the final instar, fully grown mature larvae are transferred from the rearing trays to chandrikes and allowed to build cocoons. Cocoons are then collected and marketed.
Grainage Management : This is done to provide good quality of seed to rearers and also to maintain the original quality. With this air grainage management is done by taking of caterpillar stage. They are protected from diseases and are provided good nutrition. An initial selection is made by observing pupal mortality rate. If the mortality rate is high, then such cocoons are rejected and are not kept for seed production. If the mortality rate is sufficiently low, their only such cocoons are selected and kept for seed production. The selected cocoons are kept for mass emergence. Before doing so the cocoons are examined and sexed. Males are kept separately and females are kept in separate lots.
(3) Hatching : The process by which larvae come out of the egg is known as hatching. After hatching larvae start eating mulberry leaves. The success of sericulture depends on the supply of good quality of mulberry leaves; therefore the hatching must coincide with good mulberry season. Now a days controlled hatching is done by placing the eggs in low temperature. The eggs are turned and moved with the help of a feather. Now -a-days the eggs are kept in mulberry leaves in sterilised trays. If hatching is to be delayed or controlled, the eggs are kept in separate trays and refrigerated for a suitable time.
The caterpillars which hatch out are kept in separate groups according to their age.
(4) Supply of seeds to rearers : Under this step they are supplied with seeds. The seeds are of two qualities, i.e., eggs and 2nd instar larvae. Beginner rearers are supplied with 2nd instar larvae, which experienced rearers can purchase egg. This is important operation. For this purpose government has established many silk worm seed centres from where the rearers get their seeds at fair price.
(5) Rearing of Caterpillars : The caterpillars are reared at room temperature in shady places at about 60 to 70% humidity. The mulberry leaves supplied to Ist and 2nd instar larvae are well chopped, fresh and kept in wet clothes so as to keep them fresh. The caterpillars eat voraciously and grow in size and moult. The form of larvae between two successive moults is known as instars. Larvae have five instars. The last or 5th instar larvae stop feeding and undergo pupation.
(i) Spinning of Cocoons : Full grown 5th instar larvae secrete a pasty material from its silk gland. It moves its head to and fro, secreting a silk thread.
A good quality of cocoon is judged by the quantity of raw silk, filament length, strength and splitting power. The cocoons are marketed and sold.
(ii) Post Cocoon Processing : It included following stages:
(a) Stifling : The process of killing the cocoons is termed as stifling. Eight to ten day-old cocoons are selected and dipped in hot water to kill the pupae in the cocoons.
(b) Reeling : The silk threads from the killed cocoons are removed and wound round a large wheel and then transferred to spools. This operation is called as reeling and the silk is called as reeled silk.
(c) Spinning : Damaged cocoons or the damaged outer layer of silk is separated and spun into threads. This is known as spun silk.
The raw silk is boiled, stretched, purified and washed again and again to shining lustre. Reeled silk or spun silk is marketed and sold.
Problems of Sericulture : The sericulture industry is facing a number of problems.
(1) Need for Research : There is a great need to better methods of rearing the silk worms. This is necessary to improve the yield of raw silk and reduce the cost of production.
(2) In order to improve the quality and yield of raw silk improved varieties of silk worm are developed by hybridization and breeding. There is a need for the improvement of genetic quality of the silk worm.
For research and training in sericulture the Government has opened Research and Service Station in many states. A Central Silk Board has been established at Bangalore the ministry of commerce.
Disease of silkworm
(1) Pebrine : It is the most important disease of silkworms. It is caused by a sporozoan called Nosema bombycis. The full grown caterpillar is attacked.
(2) Muscardine : It is a fungal disease caused by Beauveria bassiana and transmitted by spores carried by winds. All stages of caterpillar are attacked.
(3) Flacherie : It is a bacterial disease caused by Bacillus bombysepticus. Digestion in the affected caterpillar gets disturbed Regular feeding of the larvae and maintaining hygenic conditions will prevent the disease.
(4) Grasserie : The causative agent of this disease is the nuclear polyheadrosis virus. The affected larvae become swollen and like a bag of granules, the body fluid becomes thick and cloudy and the larvae die.
Economic Potentialities of Cultivating Silk in Madhya Pradesh : Madhya Pradesh is the largest state with respect to land area and has rich subtropical vegetation. Thus Madhya Pradesh holds vast economic potentialities of cultivating silk Sericulture is an important rural cottage industry. The tribal and other rural population in south east and east M.P. is favourably disposed for the cultivation of silk. Once M.P. was not a significant state in the list of silk producing states of India but due to the efforts of Madhya Pradesh Government in the direction of promoting sericulture today it, is the second largest state after Karnataka in the field of production of raw silk.
Efforts made by Government of M.P. to Promote Sericulture in state : A directorate of silk has been organised under the Panchayat and Rural Development Department to make concentrated efforts. These activities have been divided in two categories :
(1) Kosa silk Area : It extends in the eastern and south eastern parts of the state. This area is predominated by tribal population and is spread in the districts of Balaghat and Mandla.
(2) Mulberry silk Area : It is spread in the western and middle parts of the state including the districts of Indore, Dhar, Dewas, Khandwa, Ujjain, Shajapur, Raigarh, Mandsaur, Guna and Sehore. For the promotion of the production of Kosa silk (now Mulberry silk) following efforts are being made.
(i) Kosa Seed Centre : Twelve Kosa seed centres have been established to provide scientific and technical information to the Kosa silk worm rearers. These centres also provide disinfected improved kosa seeds and caterpillars to the rearers.
(ii) Kosa Guidance and Training Centre : Madhya Pradesh Government has established 67 centres which meet the basic needs of supplying disinfected improved seeds of Kosa silk and impart training and guidance to the rearers.
(iii) Nursery : To meet the needs of the host plant and supply of leaves to the rearers the government has established nurseries of Terminalia tomentosa and Terminalia arjuna. Plantation of host plants has been undertaken in 296 hectares of land and 1285 hectares of land is proposed to be covered under this scheme.
(iv) The construction of two grainage, one cold storage, one cocoon market and one reeling factory is being undertaken.
(v) Kosa Regional Research centre has been established to help the rearers to increase the yield and improve the quality of silk.
(3) Mulberry silk Plans : To promote the mulberry silk production in M.P. certain efforts have been made in the direction by the Madhya Pradesh Government. These are
(i) Establishment of Nursery : To increase the production of host plant Mulberry silk worm, the Morus indica, nurseries have been established.
(ii) Mulberry silk seed centres have been established.
(iii) Integrated rural development projects have prepared for the production of Mulberry silk.
(iv) Establishment of regional research centre and reeling factory.
(v) Demonstration and publicity plans.
Madhya Pradesh Government has allocated 476.22 lac of rupees for the development plans of silk For the year 1985-86 a target of 80,000 kg. of Kosa silk and 8356 kg. of Mulberry silk.
Apiculture
Apiculture is the science of rearing honeybees for obtaining honey, wax and venom. It is a profitable money-making hobby. It forms a cottage industry, when carried out on a large scale.
Three species of honey bees are commonly found in india vig. Apis indica (The small indian bee), Apis florea (The little indian bee) and Apis dorsata (the giant bee) other important species include Apis mellifera (the common European bee) and apis adamsoni (the African bee) In india the commonly domesticated species are Apis milifera and Apis Indica.
Honeybee-Apis : Like termites, honeybees are social insects known for producing honey and beeswax, and for living in very highly organized colonies. These feed upon nectar and pollen of flowers, possess “sucking and chewing” mouth parts, and undergo complete metamorphosis.
Social Organisation of Honey Bee A highly organised division of labour is found in the colony of honey bees. A good and well developed colony of bees had 40 to 50 thousand individuals consisting of 3 castes viz. queen, drone and worker.
(1) The Queen : It is a well developed fertile female provided with immensely developed ovaries. Commonly one queen is found to be present in each hive and feeds on Royal Jelly. The queen is 15 to 20 mm in length and can be easily distinguished by her long tapering abdomen, short legs and wings. Structurally she is unable to produce wax or honey or gather pollen nector. By the combination of ovipositor-cum sting, a structure is developed which aids in egg laying. It is said that the queen gets mated only in her life but in a single chance of mating, drone releases two crore sperms which are sufficient for the fertilization of the eggs at the time of laying by the female throughout her life span.
One queen lays about 1,500 – 2,000 eggs in day. In the whole life span of 2-5 years a queen lays about 15,00,000 eggs. When the queen in a colony looses its eggs lying capacity, another worker of the same colony starts feeding on queen’s diet i.e., Royal Jelly and develops into a new queen and is provided with the facilities of real queen. At the same time old queen may be driven out but sometimes some workers object that as to why the mother of the colony be driven out so ultimately they also come out with the mother. Sometimes when 2 to 3 queens are developed in a colony, only one takes the position of the real queen and the others come out with some workers to establish new colonies. This phenomenon is known as swarming.
(2) The Drone : The drone is the male member of the honey bee colony which fertilizes the queen so called as king of the colony. They are reared from an unfertile egg in large drone cell. Drone are totally dependent on the workers and have been seen begging for honey from the workers. The sole duty of the drone is to fertilize the virgin queen. At the time of mating flight the drone follows the queen, copulates and dies after copulation.
(3) The Workers : Although the workers are the smallest of the three castes but they function as the main spring of the complicated machinery like honey bee colony. Like the queen, they are also produced from the fertile eggs laid by the queen and live in a chamber called as ‘worker cell’. It takes 21 days in the development from the egg to the adult and the total life span of a worker is about 6 weeks. That is why they are provided with some special structures for particular work.
(i) Long proboscis for sucking the nectar.
(ii) Strong wings for fanning.
(iii) Pollen baskets for the collection of pollen.
(iv) Powerful sting to defend the colony against any attack.
(v) Wax gland for wax secretion.
Like all other insects the body of the honey bee is distinguish into three regions head, thorax and abdomen.
(1) Head : It is a wide triangular structure with the apex pointed below. It bears dorsolaterally a pair of large compound eyes and three ocelli on the middle of its top. From the bottom of the head project the specialized mouthparts. Mouthparts of honey bee are of chewing and lapping type, which is adapted for taking nectar from flowers and moulding the wax. The sugary fluid is sucked up by the sucking action of pharynx, it passes into the crop and regurgited and stored in the cells of comb as honey. Sugary extract of flower is converted into honey by an enzyme which produced by the glands.
(2) Throrax : The thorax is divided into three segments an anterior prothorax, a middle mesothorax and a posterior metathorax. Each of these segments bears a pair of legs and a pair of wings is borne by the mesothorax as well as metathorax. Legs are densely covered with hairs and are variously adapted.
(i) Prothoracic legs : The segments of the prothoracic are (a) an oblong coxa, (b) a short trochanter, (c) a long femur provided with pollen-carrying hairs, (d) a tibia with pollen-carrying stiff hairs, or pollen brush and a movable plate-like velum, and (e) a segmented tarsus, terminating in a pulvillus and a pair of claws.
(ii) Mesothoracic leg : The legs of mesothoracic segment have all the segments as foreleg. The tibia bears a pollen brush on its inner surface and a spine like pollen-spur on its distal end.
(iii) Metathoracic leg : Segments of the metathoracic legs are the same as prothoracic and mesothoracic legs. The tibia bears pollen basket on its outer concave surface which is partially covered by rows of long curved bristles arising from its margin. Distally the tibia is composed of rows of spines constituting the pecten. The proximal end of the metatarsus bears a concave lip-like structure, the auricle. The pecten and auricle together form a pollen packer to convey and pack pollen into, the pollen basket.
(3) Abdomen : Abdomen is made up six visible segments and possesses wax gland and stings.
(i) Wax glands : On the last four visible segments, wax cells are situated, which are modified cells on the ventral surface. Wax is produced in the form of scales through small apertures.
(ii) Sting : The sting is the modified ovipositor of the insect and is used for injecting poison. It is composed of two straight grooved stylets or lancets. A pair of filiform poison glands secretes the acidic material that is stored in a sac-like poison sac located at the base of the sting.
Life History : After mating the queen generally lays one egg in one brood cell. The eggs are pinkish coloured, elongated with cylindrical body generally attached to the bottom of the cell. Larvae emerge out from both the fertilized as well as unfertilized eggs. Thus, the larvae from the unfertilized eggs form the drones while the workers are developed from the larvae of the fertilized eggs. Amongst the larvae of the workers one is fed on the royal jelly, a special diet secreted by the young workers in the colony, and becomes the queen of the colony. The royal jelly consists of digested honey and pollen, mixed with a glandular secretion into the mouth of the workers.
(1) Swarming : The behaviour of the honey bee to come out of the hive in large number is called swarming. It takes place during the spring or early summer. It relieves the over crowding and provides a means of colony reproduction, i.e. founding of new colonies.
(2) Supersedure : When the egg laying capacity of the old queen is lost or it suddenly dies, a new young and vigorous queen takes the position of the old queen and is called as supersedure.
(3) Absconding : The migration of the complete colony from one place to another takes place due to some unfavourable condition of life, such as destruction of the comb by termites or wax-moths and scarcity of nectar producing flowers around the hive. The phenomenon is quite different from that of swarming.
(4) Nuptial or marriage flight : The prime swarm is led by the old queen while the second swarm is accompanied by the newly emerged virgin queen. About a week after emergence, the new queen takes her first aerial flight followed by a swarm of drones. The queen flies very high and drones gradually drop out of the race. The last done left in the race, mates with her. Mating occurs in the mid-air, during which the queen receives spermatophores from the drone. The sperms are stored in spermatheca or sperm-resevoir of the queen to fertilize her eggs as long as she lives. The genital parts of the male are forced out with such a great pressure that he dies after mating. Along with the queen, died drone falls one ground and the queen reaches the hive.
Bee-Hive : Honey bee is one of the few domesticated insects. In modern days bee colonies are reared in artificial wooden boxes for maximum production of honey and wax. The artificial box where the bee colony is maintained and managed is called hive. The place where hives are kept and managed is called apiary.
There are different models of hive; but the most common model in use is Newton’s hive designed by Rev. Fr. Newton. The hive is in the form of a wooden stand. The hive has two chambers. One is the upper and the second one is the lower. The upper chamber is called super or honey chamber. The lower chamber is called brood chamber. The queen is kept in the brood chamber. The two chambers are separated by a wire grid called queen excluder. The holes in the queen excluder are so smaller that they prevent the entry of the queen into the super, but allows other bees to pass through. As a result the eggs are laid only in the brood chamber. The super chamber is meant for storing honey.
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