Poultry includes the birds like chicken (hen), ducks, geese and turkey. Poultry farming deals with the rearing of them for their eggs and meat. Fowls are widely distributed as domesticated animal since time immemorial, but in the present century, it has become an important small scale industry due to modern need for palatable and nutritive food which it provides in the form of eggs as well as adult animal. An egg laying poultry bird is called hen (layers) and the poultry birds groomed for obtaining meat are called chicken or broilers.
India and the neighbouring countries, like Burma, Sri Lanka are the original home of the red jungle fowl (Gallus gallus). It seems that Aseel or Malay fowl were carried to Europe through the Middle East about 2,000 years ago and have given rise to the present-day European breeds.
Poultry farming v/s livestock rearing : Poultry birds are easy to raise, can be acclimatised to a wide range of climatic conditions, have short life span and are prolific breeders and thus poultry farming is advantageous over livestock rearing. Hens have an average yield of 60 eggs per year, but high yielding varieties can produce more than 240 eggs in a year.
Poultry contributes about Rs. 7,500 crores to the gross national product (GNP) of India. India ranks fifth in the world's egg production. Egg is one such food commodity which cannot be adulterated. The average per capita consumption is about 32 eggs and 600 grams of poultry meat a year. At present poultry is estimated to provide employment to about seven lakh families.
Raising of poultry
(1) Fowl house : Fowls can be reared in the hills of India without houses, but in the plains, well- ventilated and illuminated, dry houses are essential. A house of \[1.8\times 1.5\times 1.5\text{ }m\]has sufficient accommodation for six fowls. An open shed or verandah must be attached to this house as run to the fowls for exercise. The fowl house may be either of wood or brick and the roof is made up of corrugated iron sheets, thatch or wood. The house and shed should be cleaned daily. Fowls of different ages are kept in separate houses. In regions with moderate climate, they are kept in cages (coops).
(2) Feed : The quality and balanced quantity of food material are the back-bones of poultry. The feed given to poultry birds should contain all the essential nutrients like carbohydrates, fats, proteins, minerals and vitamins. The feed usually consists of mashed cereals like bajra, wheat, maize, jowar, ragi, rice bran and oil cakes. The fish meal' prepared from the wastes of fish processing industry and meat meal' prepared from the wastes of meat processing industry is also used to feed poultry birds.
(3) Breeds of fowls : The whole poultry industry is centred round the fowls so the selection of good breed of birds for particular area is essential. The selection of fowl breed should be based on the object with which fowls are kept. Some more...
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 more...
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.
Some breeds of Indian Sheep
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.
Biopesticides are living organisms of their products used for killing pests of interfering with their biological processes.
Bioherbicides : Biological control of weeds involves
(1) Utilization of insects which would feed selectively on weeds and (2) use of certain microorganisms which produce diseases in weeds and eliminate them. Much of the work using insects for biological control has been done in North America. In India and Australia, the overgrown of cacti was checked by the introduction of cochineal insect (Cactoblastis cactorum). The first bioherbicide was mycoherbicide, based on the fungus Phytophthora palmivora, and was developed in 1981.
Bioinsecticides : Bioinsecticides include :
(1) Pathogens, parasites and predators
(2) Sterilization strategy
(3) Insect hormones
(4) Natural insecticides
Aphids have been controlled by the use of ladybugs or praying mantis. Screw-worm was eradicated by releasing sterile males (sterilized by irradiation) at the time of mating to compete with natural fertile population. Introduction of juvenile hormones at inappropriate time results in the early death of insect pests.
Natural insecticides are obtained mostly from plants and occasionally from microbes.
Botanical insecticides and their sources
Integrated pest management is the selection, integration and implementation of pest control based on predicted economic, ecological and sociological consequences. IPM is based on the assumption that no single safe pest control. Method will be successful. IPM, therefore, seeks to use a variety of biological, physical and chemical methods integrated into a cohesive scheme designed to provide long-term protection. Biological methods include using natural predators of pests, using resistant varieties, crop rotation, intercropping, etc. Mechanical methods include manual destruction of eggs of pests, removing weeds, etc. Use of chemical pesticides is carefully timed.
The spore-forming bacteria have been particularly useful in controlling certain pests. Bacillus popilliae is used for the control of Japanese beetle. The bacterium Bacillus thuringenesis produces protein toxins. One of these, thurioside, is active against different groups of insects. Sporeine was the first bioinsecticide developed on commercial scale in Germany. Sporeine kills insects by inhibiting ion transport in the midgut. Genes for some of these toxins have been isolated and transferred to host through recombinant DNA technology (transgenic plants). Transgenic plants of tomato showing resistance to horn worm larvae have been obtained.
There are a number of chemicals which can kill or destroy these pests. These chemicals are called as pesticides (cides means to kill). Pesticides are sprayed over crops, human dwellings etc. Few familiar pesticides are baygon spray, finit (flit), DDT, BHC which are widely used in houses to kill mosquitoes, flies, ants, cockroaches etc. During the Second World War, two synthetic pesticides i.e. DDT (dichloro diphenyl trichloroethane) and \[2-4\text{ }D\](2, 4 dichlorophenoxy acetic acid) were mainly used.
Types of pesticides : Pesticides are of several types depending upon the types of pests killed or controlled. Thus they may be:
(1) Fungicides : Destroy fungal pathogens. Inorganic fungicides include Bordeaux mixture, Burgandy Mixtue, sulphur, mercuric chloride, etc. Organic fungicides are dithane \[S-21,\] dithane \[M-22,\] dithane \[Z-78\](all carbamates), oxanthiins (e.g., vitavax), mercury compounds (e.g., agrosan, tillex), benzimidiazole derivatives (e.g., benlate).
(2) Weedicides/Herbicides : They kill weeds in agriculture/horticulture and unwanted plants. Depending upon the mode of action, there are selective and nonselective herbicides, contact herbicides, translocated herbicides, foliage applied and soil applied herbicides. Herbicides can be triazines (e.g., atrazine, simazine) carbamates (e.g., thiocarbamates, phenyl carbamates) and auxin derivatives (e.g.,\[2:4D,\text{ }2:4:5T\]).
(3) Nematicides : They kill or repel nematodes, e.g., methyl bromide (MB), ethylene dibromide (EDB), chloropicrin.
(4) Rodenticides : Pesticides that kill or repel rodents, e.g., sodium fluoroacetate, warfarine, red squill, zinc sulphate.
(5) Insecticides : They kill or repel insects. Insecticides can be stomach poisons (poisonous on ingestion), contact poisons or fumigants (inhaled). Natural insecticides include Azadirachta indica (Margosa/Neem), Boenighausenia albiflora, Peganum harmala, Derris (rotenone) and Chrysanthemum (pyrethrum). First commerical bioinsecticide is sporeine developed in Germany. Synthetic insecticides are organochlorines, organophosphates, carbamates and pyrethroids, Ethylene dibromide (EDB) is a volatile liquid (fumigant) used in controlling insect pests in stored grains and fruits.
About 30% of agricultural produce in India is lost every year due to pests and diseases. Chemical pesticides are toxic chemicals used in killing pests. On the basis of chemical structure, major pesticides are grouped into: (i) Organochlorines, (ii) Organophosphates, (iii) Carbamates (iv) Pyrethroids and (v) Triazines.
(i) Organochlorines : These are basically organic compounds that have been chlorinated. Organochlorines are lipophilic and show much affinity for fatty tissue of animals. Organochlorines have very low bio-degradation, get accumulated in environment causing serious problems. Important examples of organochlorines are (a) DDT, (b) BHC, (c) Aldrin and (d) Endosulphan.
(a) DDT (Dichlorodiphenyl trichloroethane)\[{{C}_{14}}{{H}_{9}}C{{l}_{5}}\]: DDT was first synthesized by a German chemist Othnar Zeidler in 1874 and its insecticidal value was discovered by Paul Muller in 1939. DDT is the most famous pesticide of the world and is a nonbiodegradable pollutant. Spraying of DDT on crops produces pollution of air, soil and water. In India, as a result of prolonged use of DDT, 13-31 ppm of DDT can be detected in the body fat of the people, highest in the world. DDT concentrates from water into the body and magnified in higher members of the food web. DDT tolerance level is 10 ppm for Daphnia (a freshwater crustacean) and this means Daphnia more...
Due to harmful effects of pesticides on organisms, some alternative methods of pest control are being used and biological pest control is one of the suitable methods, i.e., use of other organisms to kill the pests constitutes biological pest control and such organisms are called biopesticides.
Bioherbicides/Biological control of weeds
Bioherbicides are organisms or their extracts which destroy weeds without harming useful plants. The first bioherbicide is devine, which is a mycoherbicide, based on fungus Phytophthora palmivora. It is being used since 1981 to control Morrenia odorata (milkweed vines) in Citrus orchards. Similarly Collego is another mycoherbicide from conidia Colletotrichum gloeosporioides fungus.
Bioinsecticides : They are living organisms or their products which are able to kill or repel specific insects.
(1) Use of parasites, predators and pathogens : e.g., control of aphids by use of praying mantis or lady bug, i.e., Mantis.
Bacillus thuringiensis : One of the most widely used bioinsecticides is a naturally occurring soil bacterium called Bacillus thuringiensis or Bt. that produces a protein, poisonous to insects. Insects affecting maize, cotton, cabbage, sunflowers, etc. are controlled by mutant strains of Bacillus thuringeinsis (Bt) bacteria (sporeine). Often within 15 minutes of being eaten, the poisons begin to create ulcers in the insect’s stomach lining. The insect stops eating and eventually dies. Researchers have identified between 500 and 600 strains, or types of Bacillus thuringiensis. Bt is very selective it affects only a specific species of insect pest and does not harm humans, birds, fish or beneficial insects.
Prickly pear cactus (Opuntia) in Australia and India was effectively controlled by larvae of Cactoblastis cactorum (Cochineal insect).
By use of lady bugs or praying mantis, aphids (plant bugs or homopterous insects) can be kept under control. Fluted scale insect (Icerya purchasi), a pest on citrus can be effectively controlled by lady bird beetles. Similarly mosquito larvae can be easily controlled by fish Gambusia and sugar cane scale insects are controlled by coccinellid predators.
(2) Use of natural insecticides : The insecticides of plant or micro-organisms origin are called natural insecticides. These have little toxicity for animals, e.g., Rotenone (from roots of Derris sps. and Lonchocarpus sps.); different alkaloids like Nicotine (from tobacco), Pyrethrum and Cinerin (from Chrysanthemum); Azadirachtin (from Margosa or Neem) are useful natural insecticides.
Neem or margosa (Azadirachta indica) is most useful natural insecticide. It is resistant to about 200 species of insects, nematodes, mites, etc.
(3) Sterilization technique : This is a modern method of biological pest control. In this technique, male insects are sterilized by irradiation, these are released at the time of mating and hence their multiplication is checked, e.g., screw worm (Cochliomyia hominivorax) and red weavil (a pest on coconut) have been checked by this method.
(4) Use of insect hormones (Sex attractants) : The insect hormones called pherohormones (Pheromones) are useful in controlling insects. These pherohormones attract opposite sex insects during breeding season. The natural and synthetic pherohormones are now used to attract the insects towards death traps. The Orient-fruit fly has more...
Communicable Diseases.
(i) Meaning : The diseases which are caused by pathogens (viruses and living organisms) and readily spread from the infected to the healthy persons are called communicable or infectious diseases.
A German physician, Robert Koch, listed the following four conditions to establish that a specific pathogen causes a particular disease –
(a) The suspected pathogen should be invariably present in the animals suffering from the disease and should not be found in healthy individuals.
(b) The pathogens isolated from the diseased animal should be grown in a pure culture.
(c) When this culture is inoculated into a healthy host, the latter should develop the disease and show its characteristic symptoms.
(d) The pathogen should be recoverable from the experimental host, and it should be the same as the original one.
Kotch’s postulates proposed for animal diseases, hold good for human diseases also. However, his conditions do not apply to viruses because they cannot be cultured on artificial media.
(ii) A communicable or Infectious Diseases : Caused by pathogens or biological agent. They rapidly spread from one person to another and are of great concern of the society. They are further categorised as :
(a) Viral diseases
(b) Bacterial diseases
(c) Protozoan diseases
(d) Fungal diseases
(e) Helminthes diseases
(f) Sexually transmitted diseases (STD)
(g) Diseases through blood transfusion
(iii) Control of Communicable Diseases : The Communicable diseases, beside simpering health, have been taking a heavy toll of human life in the past. Therefore, their control has always been the major problem of public health. Now, however, effective means of fighting these diseases have been found. This has not only greatly reduced the toll taken by microbes, but has also increased man’s life expectancy. Efforts to control the communicable diseases have involved three major steps –
(a) To know the nature of the disease, i.e., the causative agent and its life-history.
(b) To find out mode of transmission of the disease, i.e., how the causative agents enter the human body.
(c) To devise protective measures against the attack of the causative agent of the disease.
Reservoir of Infection for Pathogens : Every pathogen has some reservoir where it normally lives when it is outside the host susceptible to the disease. The reservoir varies for different pathogens. It may be soil, water, animals or other persons called carriers. The animals which act as reservoirs do not contract the diseases and are known as reservoir hosts.
Transmission of Diseases (Pathogens) : The diseases (pathogens) are transmitted from the reservoirs of infection to the healthy persons in the following ways :
(1) Direct Transmission : The pathogens of some diseases reach the human body directly without intermediate agents. This can occur as under :
(i) Contact with Infected Persons : Certain diseases produce sores or lesions on the skin. Contact with materials discharged from these sores or lesions brings about infection. Ringworm, athlete’s foot, more...
