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Salmonellosis is one of the important zoonoses, acute or chronic in nature, affected by all species of animals, birds and humans and characterized by gastroenteritis.

Etiology: The genus Salmonella belongs to the family Enterobacteriaceae. Currently there are 2463 serotypes (serovars) of Salmonella. According to the current system used by the CDC the genus Salmonella contains two species each of which contains multiple serotypes. The two species are S. enterica, the type species and S. bongori. The S. enterica subsp. enterica is divided into 6 subspecies. S. enterica subsp. enterica I is divided into serotypes, for example serotypes enteriditis, typhimurium, typhi and choleraesuis. The majority of 2463 Salmonella serotypes belong to S. enterica subsp. I and associated mainly with warm blooded vertebrates and are responsible for most Salmonella infections in humans and domesticated animals. Other serovars are restricted in their host range causing severe systemic disease in only one host. For example, S. typhi is restricted to infection in humans, S. abortusovis to infection in sheep, S. dublin in cattle, S. abortusequi in horses and S. choleraesuis in pigs. The serotypes (serovars) that most commonly cause Salmonellosis in farm animal species are as follows:

Cattle: S. typhimurium, S. dublin, S. newport

Sheep and goat: S. abortusovis, S. typhimurium, S. dublin, S. anaturn

Pig: S. typhimurium, S. choleraesuis

Horses: S. typhimurium, S. abortusequi, S. anatum, S. newport, S. enteritidis, S. arizona, S. angona, S. heidelbers

The organisms are Gm- and rod shaped of 1-31μX0.5-0.8μ in size. They are motile with peritrichous flagella except one type S. gallinarum pullorum which are always non-motile. They do not form capsules or spores but may possess fimbriae. Salmonellae are aerobic and facultatively anaerobic growing readily on simple media over a range of pH 6-8 and temperature 15-41°C (optimum 37°C). Colonies are large, 2-3 mm in diameter, circular and smooth. On MacConkey and deoxycholate citrate media colonies are colorless due to absence of lactose fermentation. On Wilson and Blair bismuth sulphite medium, jet black colonies with a metallic sheen are formed due to production of H2S. S. paratyphi A and other species do not form H2S, produce green colonies. Selenite F and tetrathionate broth are commonly employed as enrichment media.

It is a non-contagious, nonfebrile infectious disease of mammals caused by toxin of Cl. tetani and characterized by sposmodic contraction of skeletal muscles.

Etiology: It is caused by Cl. tetani. It is a Gm⁺, slender bacillus, 4-8μ X0.5μ in size. It has a straight axis, parallel sides and rounded ends. It occurs singly and occasionally in chains. The spores are spherical, terminal and bulging, giving the bacillus the characteristic 'drum stick' appearance. It is non-capsulated and motile by peritrichate flagella. Young cultures are strongly Gm+ but older ones may be Gm-. Cl. tetani is widely distributed in soil and in the intestine of man and animals. Soil may have good concentration O organisms if it is fertilized with animal manure. Some strains have been identified but they have same antigenic type of toxin and can be neutralized by single toxin. There are two types of antigen H (flagella) and O (somatic). The H antigen is thermolabile and O antigen is thermostable and responsible for spasms.

It is an obligatory anaerobe that grows only in the absence of O₂ It grows on ordinary media. Growth is improved by blood and serum but not by glucose. The spores are very much resistant and can persist in the soils for even years. The spores can be destroyed by boiling at 115°C for 30-60 min.

The organisms produce 3 types of toxins. The toxins are tetanospasmin (neurotoxin), tetanolysin (haemolysin) and fibrinolysin. Tetanolysin is a heat labile, O₂ labile haemolysin antigenically related to the O₂ labile haemolysin produced by Cl. welchii. This lysin is active against RBCs of several animal species. Tetanospasmin is responsible for clinical manifestation of tetanus. It is O₂ stable but relatively heat labile. It gets toxoided spontaneously or in presence of low concentration of HCHO. It is a good antigen and is specifically neutralized by the antitoxin. It exists in two forms. A monomer of MW 68,000 which is toxic and a dimer which is non-toxic but antigenic. The purified toxin is active in extremely small amounts and has an MLD for mice of about 50-75X10^-6 mg. Horse is the most susceptible animal. Guinea pig, mice, goats and rabbits are susceptible in that descending order. Birds and reptiles are highly resistant. Frogs which are insusceptible, may be rendered susceptible by elevating their body temperature.

Q fever (query fever) is an important global occupational zoonotic disease caused by a bacteria Coxiella burnetti. It is an OIE notifiable disease and showing an emerging and reemerging trend in different parts of the world. It is having great public health importance as the pathogen is transmitted through almost all routes but predominantly by aerosols from reproductive discharges of animals of farm and pet animals which serve as main reservoir of infection. The organism is shed in milk and foods of animal origin for very long period. Q fever is associated with a wide clinical spectrum and most of its acute infections are either asymptomatic, mild or resemble to influenza. Presently, the infection is endemic in many areas and its prevalence has been confirmed in at least 51 countries including India.

Etiology: C. burnetti was classified as a member of Rickettsiaceae family however, recent scientific investigations on 16S RNA based sequence analysis have shown that it is genetically more comparable to bacterial families covering genus Francisella and Legionella therefore it has been reclassified in the family Coxiellaceae or order Legionellales. It is a Gm-, pleomorphic rods (0.2-0.41μX0.4-1.0μ) or sphere (0.3μ-0.4μ in diameter in size) and an obligate I/C organism. It is relatively resistant to physical and chemical agents. The bacterium occurs in two antigenic forms - the pathogenic form (phase I) found in infected animals or humans and the avirulent form (phase II) obtained by repeated passagein embryonated eggs or in cell culture. Phase II cells are autoagglutinable and are readily phagocytosed in the absence of specific antibodies. Phase I activity is attributed to surface carbohydrate antigen which is soluble in trichloracetic acid and is destroyed by periodate. Phase I is a more powerful immunogen than phase II and elicits antibodies in high titer to both antigens. Phase II antigen gives better results in CFT with human and animal sera. Q fever sera do not react with other rickettsial antigens or with Proteus. In nature, bacterium exists mainly in 3 forms, namely - the small cell variant (SCV), the small dense cells (SDC) which are spore like forms that remain very stable in the environment as extracellular infections particles and the large cell variant (LCV) which is the growing and metabolically active form inside the host. In view of the potential for transmission of this infection from animal to people, the disease has been classified as a notifiable OIE disease.

SUMMARY

Agriculture is the largest user of fresh water for irrigation to fulfill the increasing demand of food, feed, fiber, fuel and other need of ever-increasing population. Water availability to agriculture is characterized by declining in share with time, over exploitation, improper mismanagement, deterioration in quality as well as environment. This could be addressed using sustainable management of irrigation water. As per the Brundtland Commission report of United Nations, sustainable development is the development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable water management aims to improve water productivity, availability and quality over an area.  Improved and efficient irrigation techniques and practices enhance water application efficiencies, and thereby reduction in associated damage to environment, which include water logging, soil salinity, runoff and leaching of nutrients and other chemicals polluting water sources, and over exploitation of ground water. Micro irrigation systems have been characterized to be the most efficient irrigation techniques. These have efficiencies even more than 90%, doubled water productivity with improved quality of produce, reduced runoff and leaching of nutrients and chemicals to water sources. Application of fertilizer through drip irrigation called fertigation could be adopted for efficient use and saving of fertilizer.  Fertilizer savings of 20-60% and 8-41% increase in yields of horticulture and vegetable crops has been realized through fertigation.

SUMMARY

Green manuring is the practice of growing lush plants on the site into which organic matter directly incorporate to the soil while it is still fresh. Green manures, often known as cover crops, are plants which are grown to improve the structure and nutrient content of the soil. They are a cheap alternative to artificial fertilizers and an eco-friendly input for organic farming and can be used to complement animal manures. Growing a green manure is not the same as simply growing a legume crop, such as beans, in a rotation. Green manures are usually dug into the soil when the plants are still young, before they produce any crop and often before they flower. They are grown for their green leafy material which is high in nutrients and protects the soil. It is basically a holistic management system, which promotes and improves the health of the agro-ecosystem related to biodiversity, nutrient biocycles, soil microbial and biochemical activities.

SUMMARY

Citrus is third most important fruit crop in India after banana and mango. Citrus crops have occupied an area of 8.43 lakh ha with total production of 75.7 lakh tons and the productivity of 9.9 tons/ha in India. Such a quantum of citrus production contributes 13 per cent of total fruit production demonstrating the significance of citrus in horticultural research and development in India. Rootstocks are known to have profound effect on the vigour, precocity, productivity, internal quality, and longevity of the scion varieties grafted on them. They are also known to influence the susceptibility of trees to various diseases and insects. Furthermore, it is recognized that optimum performances depends on the proper selection of rootstocks for a given set of growing conditions. The most commonly and widely used citrus rootstocks in India are Rough lemon, Cleopatra and Pectinifera. Rough lemon (Jatti Khatti) is the most important and widely used rootstock in the country for most of the scions followed by Kharna Khatta being more popular in Uttar Pradesh. While the problem of rootstock selection is important in all major fruit crops, it is of even greater importance in citrus due to tristeza virus disease now present in many areas of the world. It is also possible that citrus decline in India may be due partly to stionic incompatibilities. This chapter deals with problems and prospects of rootstocks in citrus in India, particularly related to horticultural aspects, insect-pests, diseases, nematodes, physiological disorders, post harvest quality, aspects related to tissue culture and rootstock breeding.

SUMMARY

Fly ash, a waste product generated by coal based thermal power plants. The annual production of fly ash in the country has increased from 40 million tones in 1994 to 110 million tones in 2004 and it is expected that by 2012 the annual production of fly would reach the mark of 170 million tones. Owing to its physico-chemical characteristics, it has a vast potential for use in agriculture, forestry and wasteland reclamation. Application of fly ash into soil has been reported to increase the water holding capacity, hydraulic conductivity, porosity and decrease bulk density, modulus of rupture and surface encrustation. The studies conducted by various organizations on fly ash use in different crops have revealed significant increase in the crop yields such as wheat, maize, paddy, soybean, sunflower and vegetables like brinjal, tomato, potato, cabbage. Application of fly ash has been found to increase the level of heavy metals  viz., Co, Pb, Mo, As and Se as well as the activity of radio-nuclides i.e., ⁴⁰K, ²²⁶Ra, ²²⁸Ac  in the soil- plant system; however, the levels of all these heavy metals and radio-nuclides were found to be well below the permissible limits.

SUMMARY

Sustainable agricultural development can only be possible, when all agricultural inputs used judicially. Soil management practices, like nutrient management, time schedule of fertilizer application, irrigation management etc. are should be manage in such away that resulted in best remuneration and sustain overall soil health. More over that, soil physical properties like, tilth, aeration and drainage are also play important role in soil productivity, so tillage operation should be carry out at proper  level of soil moisture condition to maintain good soil tilth which result in better soil environment for high crop yield. The most important factor in sustainable soil management for agricultural development is nutrient management and it's only possible through integration. So nutrient management through integrated approaches, like use of chemical fertilizer is decreases by integrating with organic manures, biofertilizer, green manure, neem cake, caster cake etc which resulted in sustainable crop production and good soil health on long-term basis.

SUMMARY

The primary requirement for sustainable agriculture is the maintenance of a satisfactory balance of water, air and salt in the root zone encouraging for plant growth. This balance can be achieved by sufficient drainage. About 22% of the World's irrigated area is affected by waterlogging and salinity. Vertical drainage by pumping can control the increase of ground water table in those areas where the ground water is of good quality. Horizontal sub-surface drainage in which the saline ground water is drained away through pipes and drains, is the other regularly used anti waterlogging methods. In bio-drainage system, the characteristic of the trees to transpire water is used to control the increase of ground water table. It is an alternative drainage method, which would be most economical and environmental congenial. But there are worries and doubts on the long-term sustainability of biodrainage. This chapter describes various aspects of biodrainage.

SUMMARY

At present, Indian agriculture faces a severe challenge for the future in view of growing demand for food for meeting the needs of nation’s ever growing population. At the same time, resources are gradually shrinking and the productivity of some resources is already being utilized threatening the sustainability and leading to environmental degradation which necessitates judicious and sustainable management of natural resources, particularly soil and water. Of 142 m ha arable land, nearly 96 m ha (67%) is devoted to rainfed farming, which contributes about 44 % of the total production. Overexploitation of water resources, unequal access to water and adverse impacts on ecosystem services are among the major issues impacting sustainable use of water resources. Crop production in rainfed areas is generally affected by chronic drought, ephemeral drought, and apparent drought. In order to increase production, farmers have two options, either to use extensive systems (horigental) or intensive systems (vertical). There is a meager scope for extensive system in India and the remaining intensive system is the only option for the farmers as well as policy makers. Hence, optimizing soil water management is crucial to enhancing agronomic productivity and meeting the food needs of the growing population with rising standards of living under rainfed area.

SUMMARY

Conventional agriculture has been contributing significantly to several modern day environmental problems like global climate change, soil degradation, water pollution, biodiversity loss etc. directly or indirectly. Organic agriculture has been identified as one of the eco-friendly agriculture techniques and is being promoted worldwide to meet the increasing demand for organic products and conserve the natural eco-systems. It helps mitigating climate change through reduced emission of green house gases (GHGs), greater C sequestration and less use of fossil fuel. Besides, it has been found helpful to reduce export of harmful agro-chemicals to water bodies, biodiversity conservation, restoring soil health etc. Organic agriculture can help to meet the objectives of sustainable and eco-friendly agriculture.

SUMMARY

Seed quality comprises the sum of all properties or characteristics, which determine the potential level of the seed or seed lot performance and crop establishment. Once the seed is sown many factors (biotic, abiotic etc.,) influence its survival and potential. Seed priming is one of the short–term and most programmatic approaches followed to improve the quality of seed so as to exhibit maximum possible potential even under adverse conditions. Seed priming is a method that well fit in to the one or more principles of sustainability, as it is practiced as a low-cost, low-risk interventions that increase and stabilize yields to have a large and direct impact on the livelihoods of farmers. Various priming methods viz., hydro priming, halo priming, matrix priming, bio priming are in practice for advancement in seed germination, better crop growth and yield. The adoption of seed priming as a successful technology is widely practiced across the Globe for various benefits at farm level. On-farm seed programme is one such   successful programmes adopted under UK aid across 11 countries towards sustainable agriculture campaign.

SUMMARY

The natural drainage systems are severely affected by the development processes and thus increased in waterlogged and salt affected areas. In major and medium irrigation projects due to inadequate designs coupled with poor management practices has raised groundwater table and in turn sizeable command areas are being affected both by water logging and soil salinization, Water logging and salt problem have been experienced in irrigation projects all over the country. Both adversely affect the growth and the yield of the crops. An area with water table within 2 m from the land surface is called as water logged area. It is potential to water logging if water table is between 2-3 m from the land surface. It has been estimated that around 16.71 million hectare land is affected by salt and waterlogging in India. The drainage is the remedy to these problems for sustainable agriculture.

            Drainage is defined as the natural or artificial removal of surplus ground- and surface water and dissolved salt from the land in order to enhance agriculture production. In the case of natural drainage the excess waters flows from the fields to lakes, swamps, streams and rivers. However, in an artificial system surplus ground or surface water is removed by means of sub surface or surface conduits. Improved drainage create a healthier environment for plant growth, It conserve soil and water; and provide drier field conditions for ease in farm operations for the crop production. Agricultural drainage is must to realize the full benefit of irrigation.

SUMMARY

To meet the food requirement of spirally growing population we need to produce more crops per unit area of land. Soil is the raw material for land and is the outer covering of earth surface. It is a very important resource and gift of nature for the substrate where plant can grow. Agriculture is the backbone of our country, and agriculture mainly dependent on soil quality. The success management of soil quality depends on the mechanistic approach, how soil responds to agricultural use and practices over times. As soil degradation grows day by day there is a big challenge against agriculture to sustain. Now days the main cause for soil degradation is non-planed use of land resources. This is the time when we think about this big challenge and face it for the future generation which we need to manage the soil quality for self sustainability. Because adaptation of appropriate soil management scientific methodologies and land use planning could replenish the degraded soil properties for sustainable agriculture which is need of the hour.

SUMMARY

Vegetables play a pivotal role in food and nutritional security of the ever increasing population of our country. The vegetarian society largely depends on vegetables for the want of their nutritional requirements. Vegetables are exhaustive crop with an exceedingly high turnover of plant nutrients, Thus , nutrient element required for optimum growth and development of vegetables should supplied to soil and plants in right time and in a balanced and integrated mode. Neither the chemical fertilizers are alone nor the organic sources exclusively able to sustain the soil fertility/productivity. The national average productivity of different vegetable crops of our country at present is much below the potential productivity. It may be increased up to 2-3 times more by adoption of appropriate nutrient management practices. The majority of our Indian soils are deficient in about 7-8 macro and micronutrients which leads lower productivity. Integrated nutrient management (IPNM) is one of the recent methods of supplying nutrients to the plants by organic as well as inorganic means together to fulfill the nutrient requirements. Organic manures are the key characteristics including the long term fertility of soil by maintaining organic matter levels, fastening soil biological intervention, nitrogen fixation as well as effective recycling of organic materials including crop residues and live stock wastes and weed. Micro - organisms play an important role in various chemical transformations in soil and thus, influence the availability of major nutrient like N, P, K. and S to the plant.

SUMMARY

Plant tissue culture mainly comprises a set of in vitro techniques, methods and strategies that are part of the group of technologies called plant biotechnology. Tissue culture has been exploited not only to create genetic variability from which crop plants can be improved but also to improve the state of health of the planted material and to increase the number of desirable germ plasms available to the plant breeder through a shorter duration in cost effective manner. Tissue-culture protocols are available for most crop species, although continued optimization is still required for many crops, especially cereals and woody plants. Tissue culture techniques, in combination with molecular techniques, have been successfully used to incorporate specific traits through gene transfer. In vitro techniques for the culture of protoplasts, anthers, microspores, ovules and embryos have been used to create new genetic variation in the breeding lines, often via haploid production. Cell culture has also produced somaclonal and gametoclonal variants with crop-improvement potential. The culture of single cells and meristems can be effectively used to eradicate pathogens from planting material and thereby dramatically improve the yield of established cultivars. Large-scale  micropropagation laboratories are providing millions of plants for the commercial ornamental market and the agricultural, clonally-propagated crop market. With selected laboratory material typically taking one or two decades to reach the commercial market through plant breeding, this technology can be expected to have an ever increasing impact on crop improvement as we approach for the need of the hour .

SUMMARY

Fertigation is the injection of concentrated soluble nutrients into irrigation water to enhance crop production. It is used extensively in commercial agriculture and horticulture. In combination with micro-irrigation (drip irrigation), this technique forms an efficient method for precisely applying nutrients close to the crop root zone, especially when a polyethylene mulch is used. Fertigation is used to spoon feed additional nutrients or correct nutrient deficiencies detected in plant tissue analysis and usually practiced with high value crops such as vegetables, turf, fruit trees, and ornamentals. Water supply for fertigation kept separate from domestic water supply to avoid contamination. Fertilizing fruit and vegetable crops requires a delicate balance between yield, quality, and environmental impact. Fertigation increases response to nitrogen (N) and provides greater opportunity to control rates to optimum levels to the root zone. Providing nutrients through the irrigation system enables more flexibility in a fertilizer program. Several types of irrigation systems are available for use in crop production. For any system used, approved backflow control valves and interlock devices are necessary to prevent accidental contamination of the water source due to irrigation system failure or shutdown.

SUMMARY

In the context of increasing population pressure, diminishing per capita land holding, and employment crisis, livelihood security of Indian rural population has become important concern today. The livelihood of the people is dynamic, diverse and complex in nature. The livelihood comprises the people themselves, the assets they posses, the activities they do and the output they gain from their activities. According to the need, availability of the resources and capacity, people used to select their livelihood strategies like agricultural intensification, livelihood diversification or they migrate to the other places to find alternative livelihoods.

SUMMARY

Abiotic stress can be reduced by choosing the most appropriate pulse species and adjusting agronomy (sowing time, plant density, soil management) to ensure sensitive crop stages occur at the most favourable time in the season. For example choosing the optimum sowing time, species and cultivars with appropriate phenology can reduce the effect of frost and drought in pulse crops in dry land environments, which termed stress.

             Most appropriate approach of dealing with stresses caused by extremes in the abiotic environment is to develop cultivars resistant to specific stresses. However, breeding and selection for resistance to these stresses is often considerable difficult because of the unpredictability of climatic conditions. Drought and heat escape through earliness in flowering and maturity is probably the characteristic most widely used by breeders for pulses and other crops to escape drought especially in low rainfall, terminal drought environment. Lack of simple and accurate screening procedures to screen parental genotypes and breeding population for various abiotic stresses is the major bottlenecks in the development of stress tolerant cool season pulse crops.

SUMMARY

Organic farming is not new to Indian farming community. Several forms of organic farming are being successfully practiced in diverse climate, particularly in rainfed, tribal, mountains and hill areas of the country. Among all farming systems, organic farming is gaining wide attention among farmers, entrepreneurs, policy makers and agricultural scientists for varied reasons such as it minimizes the dependence on chemical inputs (fertilizers; pesticides; herbicides and other agro-chemicals) thus safeguards/improves quality of resources, and it is labour intensive and provides an opportunity to increase rural employment and achieve long term improvements in the quality of resource base. The popularity of organic farming is gradually increasing and now organic agriculture is practiced in almost all countries of the world, and its share of agricultural land and farms is growing.

SUMMARY

Multiplicity of cropping systems has been one of the main features of Indian agriculture and it is attributed to rain-fed agriculture and prevailing socio-economic situations of farming community. It has been estimated that more than 250 double cropping systems are followed throughout the country and based on rationale of spread of crops in each district in the country, 30 important cropping systems have been identified. Cropping systems of a region are decided by and large, by a number of soil and climatic parameters which deter mine overall agro ecological setting for nourishment and appropriateness of a crop or set of crops for cultivation. Much of the Madhya Pradesh area also coincides with the rainfed semi-arid agro-ecological region and sub-regions which are upland, forested with low agricultural productivity and predominately tribal population. It would appear that over the centuries – including in recent history tribals have been inexorably moved off the better lands, into areas which from an agricultural perspective have low productive capacity and little potential for growth. Low agricultural productivity is one of the main causes of persistently high poverty rates in the state and the poor masses not only depends upon the farming system but also chosen different alternatives for their sustanability.

Sir Alexander Ogston (1880) first isolated Micrococci in pus and in 1883 he subdivided them into two groups i.e. Staphylococcus and Streptococcus. He also first proposed the name ‘Staphylococcus’ (Greek ‘staphyle’ means bunch of grapes and ‘kokkos’ means berry). Experiments of Bumm (1885), Garre (1885) and Bockhart (1887) established its relationship with human infections. As well as Nocard (1887) first isolated Staphylococcus from mastitis in sheep and found its pathogenic significance in animals.

Properties of Genus

Morphology : Staphylococci are gram positive cocci, capsulated, non-sporing and non-motile. Each coccus cell is 1µm in diameter.  They are arranged in a group or grape like cluster as cell division occurs in more than one plane. During preparation of smear and staining the cluster is sometimes broken and cocci are seen in pair or single (Fig. 1).

Staphylococcal capsule is polysaccharide in nature. The capsule can inhibit phagocytosis and helps in virulence.

 Staphylococcal cell wall contains three major components i.e. peptidoglycan (PG), teichoic acid (TA) and surface proteins.

Rivolta (1873) first described the chain forming cocci in pus collected from the equine infection. Later Rosenbach established the genus ‘Streptococcus’. Nocard and Mollereau (1887) first observed the relationship between the bovine mastitis and Streptococcus agalactiae.

Properties of genus

1. Morphology : Streptococci are gram positive cocci, capsulated, non-sporing and non-motile. Each coccus cell is 1µm in diameter.  They are arranged in a pair or chain of cells as the cell division occurs in one plane (Fig. 1). The chain formation and the chain length are variable. Streptococcus equi ssp equi is a constant chain producer, other species are not. The chain length is shorter in artificial media than natural one. Young cultures are gram positive whereas the bacteria present in the pus and older cultures in the laboratory are often stained as gram negative. 

Streptococcal capsule is polysaccharide in nature. It can be subdivided into different antigenic types (e.g. S. agalactiae, S. pneumonae). However capsules of S. equi, S. pyogenes are made of nonantigenic hyalu-ronic acids containing repeating units of glucuronic acid and N-acetyl-glucosamine. Synthesis of the polymer involves the products of three genes, hasA, hasB, and hasC, which are all in the same operon.

In 1850, Bacillus anthracis was first reported by three individuals in two different countries i.e. Delafond (who may have found them as early as 1838) and Davaine in France, Pollender in Germany. However, they could not establish the relationship between the disease and the bacterium. Absolute proof of the anthrax etiology as B. anthracis was established by Robert Koch in 1876-77. The name Bacillus anthracis was first coined by Cohn (1875) and the disease ‘anthrax’ was first named by Hippocrates (5th century B.C.). In Greek language meaning of anthrax is ‘coal’ referring to the black coloured skin or blood in affected animals.

B. anthracis organism has certain historical importance:

a)   Anthrax is the first disease identified to be caused by a bacterium.

b)   Robert Koch first isolated the organism and reproduced the disease in experimental animals. He proposed his postulates (Koch’s postulate, 1876) based on his experiments related to this organism. It later became a fundamental milestone of all microbiological works related to the infectious diseases.

c)   Louis Pasteur first used heat attenuated culture of B. anthracis as vaccine in a group of sheep in 1881 at Pouilly-le-Fort. He cultured the organism at 42-43^oC in presence of oxygen. The bacteria did not produce spores and became attenuated.

d)         First concept of bacterial antagonism was provided by Louis Pasteur and Joubert based on their work on this organism. Injection of other unidentified bacteria along with B. anthracis can prevent anthrax in animals
.

The genus Clostridium belongs to the family Clostridiaceae. The genus name was originated from the Greek word ‘kloster’ means spindle, referring to their individual rod shape. Clostridia are gram positive, large, sporulating anaerobic rods (except C. piliforme which is gram negative). At present, there are more than 200 numbers of species under the genus Clostridium. Among them, 15 species can produce potent toxins and are considered as pathogenic for animals and human. The animal pathogenic Clostridia can be classified as neurotoxic, histotoxic and enteric.

In 1882, Robert Koch first isolated the organism, stained with alkaline methylene blue and vesuvin as counter stain and proved its etiologic relationship with Tuberculosis.  Ehrlich first developed acid fast stain in 1882 and used for better staining of the bacteria which was adopted by Robert Koch. Later this staining technique was modified by Ziehl-Neelsen, accordingly it is now a day known as Z-N staining. In 1890, Koch prepared a glycerine broth extract of the tubercle bacillus, known as ‘tuberculin’.

      He tried to prepare it as a curative agent; however, it was used later in diagnosis. In 1895, Johne and Frothingham described the first case of paratuberculosis in cattle, later known as ‘Johne’s disease’. Although, the causative agent was first isolated by Twort and Ingram in 1910.

            In India, bovine Tuberculosis was reported from several states since 1959 (Dhanda and Lal, 1959). Whereas bovine paratuberculosis was first reported by Nanda and Singh (1940) in Hissar, Haryana.

This family Enterobacteriaceae belongs to the order Enterobacteriales. The family comprises 25 genera. Among them there are 10 genera consistently found pathogenic for animals, birds and human. These genera are mentioned below (first 10 are consistent pathogenic).

In 1886, Escherich observed Campylobacter like organisms in stool samples of children with diarrhoea. In 1913, McFaydean and Stockman first confirmed them as Campylobacter in foetal tissues of aborted sheep. Confirmatory tests were also carried out by Smith in 1918 when similar organisms were isolated from aborted bovine foetuses. The organism was then known as Vibrio foetus. In 1963, due to certain differentiating characteristics, the organisms were separated from Vibrionaceae family and the new genus Campylobacter (means ‘curved rod’) under Campylobacteriaceae family was proposed. 

Properties of genus

1.   Morphology :  Campylobacter is gram negative, comma shaped rods specially in infected tissues and young cultures. The size is 1.5-4 µm by 0.5 µm. When two bacterial cells are found together in a microscopic field, it looks like ‘S’ or ‘wing of gull’ (‘flying seagull’). However in older cultures, the chains of organism appear as long spirals. They are motile by single unipolar/ bipolar unsheathed flagella. Motility is darting or corkscrew type, best observed by dark field microscopy. They are non-sporing. Some species contains S-layer (surface layer), a paracrystalline protein structure composed of S-layer proteins (SLPs). It is external to the outer membrane. It helps the bacteria in immune evasion.

Clinical conditions similar to Brucellosis have been described since the time of Hippocrates (450 BC). J. A. Marston first described brucellosis as gastric remittent fever in 1861 at Malta (Marston, 1861). Sir David Bruce in 1886 first isolated little coccobacillus from an infected soldier’s spleen. However he isolated the bacteria in a pure culture in 1887 and named Micrococcus melitensis (Bruce, 1889). Later the genus was renamed as Brucella in his honour. Similarly, Bang and Stribolg first isolated Brucella abortus from abortion material of a cow (Bang, 1897). Traum in 1914 isolated the Bacillus abortus suis. Presently we know it as Brucella suis. In 1953, Brucella ovis was first isolated in New Zealand (Budlle and Boyes, 1953) from the aborted material of sheep. Carmichael and Bruner in 1968 first isolated B. canis from the aborted placenta of a dog.

            In India first report of ‘Contagious abortion’ by Brucella was found from annual report of Imperial Veterinary Research Institute (presently Indian Veterinary Research Institute), Mukteswar, Uttarakhand (Anonymous, 1918). Seroprevalence of Brucellosis is reported from various states of India afterward (Polding, 1942; Sethi et al., 1971 etc.).

Pasteurella and Mannheimia species are gram negative small coccobacilli under family Pasteurellaceae. Trevisan (1887) coined the generic name Pasteurella for the first time and it was accepted worldwide. Lignieres (1900) proposed the specific name for each organism according to the species of animal host: Pasteurella aviseptica for fowls; P. suiseptica for pigs; P. boviseptica for bovines; P. oviseptica for ovines and P. leptiseptica for rabbits. Finally, Rosenbuch and Merchant (1939) proposed a single species Pasteurella multocida and it is in use till date. 

      Mannheimia haemolytica was earlier known as Pasteurella haemolytica, but because of variations in cultural, pathological and 16S rRNA sequence, it is placed in separate genus.

Properties of genus

Morphology : P. multocida is a non motile, non spore-forming short rod or coccobacillus, 0.2-0.4 by 0.6-2.5 µm in size. Repeated laboratory subcultures or cultures grown under unfavourable conditions tend to be pleomorphic and longer rods or filamentous forms appear. In tissues, exudates and recently isolated cultures, the organism shows the typical coccobacillary forms. It is a gram-negative organism and, in fresh cultures and animal tissues, gives typical bipolar staining (Fig.1), particularly with Leishman or methylene blue stain.

Lucke (1862) first described that the bluish green discolouration of surgical dressing is associated with the presence of small vibrio like organisms. Latter Gessard first isolated the organism as Pseudomonas in 1882.

Properties of Genus

1. Morphology : They are Gram negative straight or curved rod, motile by one or more polar flagella. Usually it is 1.5 µm in length and 0.5 µm in width. Longer filamentous forms are sometimes observed. The bacteria are non- acid fast, non- sporulating and uncapsulated. Pili on the bacterial surface are detected. Environmental and strains present within tissue can produce slime. The slime is composed of glycolipoprotein (GLP) and polysaccharide of LPS.
    
2. They are strict aerobe.

Classification : Pseudomonas belongs to class Gamma-Proteobacteria, order- Pseudomonadales, family- Pseudomonadaceae.  Previously Pseudomonas included two group of bacteria viz. Fluorescent group and Pseudomallei group. Recent classification system included this Pseudomallei group into a new genus known as Burkholderia. Important species of Pseudomonas are:

The genus was named after Morax who first isolated the organisms from human conjunctivitis in 1896.

Properties of genus

1.   Morphology :  Moraxella are gram negative, small rods occurring in pair (diplobacilli). The aged cultures exhibit pleomorphism, occurring in pairs or chains as short, plump rods with rounded ends. Some strains may appear as cocci. The capsule is present in fresh isolates of some species (except Moraxella catarrhalis). They are non-motile and non-sporing. Moraxella bovis contains numerous type IV fimbriae on its surface.

2.   Moraxella is aerobic, fastidious and non-fermenting in nature. However, some strains prefer anaerobic condition for their growth.    

3.   Classification : The genus Moraxella belongs to the Moraxellaceae family. Previously it was known as Branhamella. Most of the species are commensal except a few, which have disease producing capabilities. Important species are M. bovis, M. ovis, M. catarrhalis, M. boevrei, M. canis, M. caprae, M. caviae, M. cuniculi, M. phenylpyruvica.

4. Resistance : Resistance to physical and chemical agents is not remarkable. They are susceptible to desiccation and do not survive long outside the host. The beta- lactam antibiotic resistance is observed among M. catarrhalis isolates from clinical cases. This resistance is associated with the production of beta-lactamase enzyme.

Pfeiffer first isolated and described Haemophilus influenzae as a cause of human influenza (1892). So it is also known as ‘Pfeiffer’s bacillus’. Later other workers isolated and described different species of the genus Haemophilus from animals and birds. In 1903, Friedberger, a research assistant of Pfeiffer, isolated similar kind of organism from prepuce of the dogs. In 1922, Rivers described it as Haemophilus canis. In 1925, Mitchell isolated Haemophilus ovis from the respiratory tract of sheep. In 1931, Lewis and Shope first isolated and illustrated Haemophilus suis from the infected pigs. Glasser found an association between fibrinous serositis, polyarthritis in pigs (Glasser’s disease) and a small gram negative rod as early as 1910, latter became known as Haemophilus parasuis. It was first isolated by Hjarre and Wramby in 1943.  The first recorded isolation of a hemophilic organism from the birds was in 1931 by De Blieck and he called them as Bacillus haemoglobinophilus coryzae gallinarum. He isolated them from the chickens suffering a disease, now known as ‘infectious coryza’.

Taylorella was first isolated by Taylor et al. (1978) as a causative agent of contagious equine metritis (CEM), a venereal disease of horses. The disease (CEM) was first reported in the mares of thoroughbred horses in UK in 1977 breeding season (Crowhurst, 1977). Initially the causative agent was assumed as Haemophilus equigenitalis. Later on the basis of numerical taxonomic characteristics, genomic G+C contents, DNA-DNA hybridisation studies, the new genus Taylorella was proposed in 1983 (Sugimoto et al., 1983). It was approved by the International Committee on Systematic Bacteriology.

Properties of genus

1.   Morphology :  Taylorella are gram negative, small rods or coccobacilli, measuring 5-6 µm by 0.8 µm. They are pleomorphic, piliated, encapsulated, non-sporing and non-motile.

2.   They are microaerophilic (require low O₂ tension for growth), non-fermentative, and non-proteolytic in nature.

3.         Classification : Taylorella belongs to β- subclass of class Proteobacteria (whereas, Haemophilus belongs to the γ- subclass of Proteobacteria). Major important species is Taylorella equigenitalis. The genus was considered as a ‘single species genus’ for a long time. Latter in   1997, National Veterinary Services Laboratories confirmed the identity of another Taylorella species, isolated from a donkey jack (Equus asinus) in California. It was named as T. asinigenitalis. The new species has minor difference in 16S rDNA sequence (97.6% similarity), DNA–DNA hybridization (23% similarity) and (G + C) composition with T. equigenitalis (Matsuda and Moore, 2003)
.

Listeria

Murray et al. (1926) first described about Listeria which was followed by Pirie et al. (1927). In India Listeriosis was first reported by Mahajan (1936) in sheep from Andhrapradesh. He recognized it as ‘circling disease’. Latter a number of reports are available from various parts of India.

Lignieres and Spitz first isolated the bacteria from the cattle with Actinomycosis like condition in Argentina in 1902. They referred them as ‘Actinobacilllus’. These findings were also confirmed by Nocard in 1902. Latter, the isolated bacterium from the cattle was named as Actinobacillus lignieresii, in memory of Lignieres. 

Properties of genus

1.   Morphology :  Actinobacillus are gram negative small rods, measuring 1.5 µm in length and 0.4 µm in width, occurring singly, in pairs or more rarely in chains. After isolation in the laboratory they may show pleomorphism varying from coccobacilli to filamentous forms. In gram stained smear they may show both bacillus and coccus form together, known as ‘morse code’ appearance (dots and dashes appearance, Fig.1). They are non-motile (both at room temperature and 37^oC), non-sporing and non-acid fast. The pili are found in A. pleuropneumoniae.

      Some of them (A. pleuropneumoniae) are capsulated. Whereas, slime layer is found in the surface of other species like A. lignieresii, A. suis, A. equuli.  This slime layer is related with stickiness of the colonies in the agar, enhanced resistance of the colonies to the chemical disinfectants, as well as, resistance of the bacterial cell to the antibiotics and desiccation.

2.         Actinobacillus are aerobic, microaerophilic or facultative anaerobic in nature. They are chemoorganothrophic having both respiratory and fermentative types of metabolism.

Cohn (1875) first observed and described a branching filamentous micro-organism in the concretions (coagulated mass) taken from a lacrimal canal, latter identified as Actinomyces israelii. Bollinger first reported the yellow granules in jaw tissues of the cattle in 1877 and established the significance of the organisms as an etiological agent. In 1878, Israel described the first human case. In 1879, Hartz observed the microscopic appearance of granules of Actinomyces infection and suggested the name Actinomyces bovis. Mosselman & Lihnaux (1890) and Wolf &Israel (1891) first isolated the bacteria in artificial laboratory media from lumpy jaw cases of cattle and human Actinomycosis, respectively.

Properties of genus

1.         Morphology :  Actinomyces are gram positive filamentous organisms with branching rods. In artificial media, short bacilli or cocci forms are also observed. During infection, they can produce yellow coloured granules (sulphur granule), commonly found in the pus as ‘opaque speck’ and are visible under naked eye (1-2 mm in diameter). The granules are usually soft and easily broken under light pressure, but they may occasionally be tough or even calcified. They are composed of club shaped bodies, arranged radially with their narrow ends towards the centre. So the organisms are also known as ‘ray fungus’. In the centre of the club, filamentous masses of gram positive organisms with some bacilli or cocci form are found. Together the club like processes and bacterial masses are known as ‘rosette’ (Fig.1). This club is composed of calcium phosphate and inflammatory debris
.

The genus Arcanobacterium was first described to include the bacteria originally isolated as Corynebacterium haemolyticum from American wounded soldiers (Collins et al., 1982). The bacteria had different cell wall and lipid composition in comparison to the other members of the genus Corynebacterium. So the new genus Arcanobacterium was created.

Properties of genus

1.         Morphology : Arcanobacterium pyogenes is a Gram positive, non-motile, non- spore forming, short, rod-shaped bacterium, measuring 0.5µm by 2 µm. They are non-capsulated and do not contain any metachromatic granule. Initially (during first 18 hour of growth) the bacterial cells may show characteristic ‘V’-arrangement like Corynebacterium, latter as the growth proceeds, the organisms become granular and segmented so that they resemble small and irregular cocci (whereas, A. hippocoleae and A. pluranimalium appear to be less coccoid). The cell wall is devoid of mycolic acid, arabinogalactan unlike ‘coryneform’ bacterial group (Mycobacterium, Corynebacterium, Rhodococcus, Nocardia). Cell wall peptidoglycan is composed of N-acetyl muramic acid, lysine. Being gram positive in nature, some strains exceptionally possess fimbriae.

Corynebacterium diptheriae was first observed by Klebs in 1883 and described in details by Loeffler in 1884. So it is also known as ‘Klebs-Loeffler bacillus’. In 1888, Nocard isolated a similar type of bacteria from cases of bovine farcy. In 1894, Preisz described it completely and revealed its similarities with the diphtheria bacilli. Latter it was named as Corynebacterium pseudotuberculosis (Preisz-Nocard bacillus). Bollinger (1890) first reported C. renale from the cases of pyelonephritis in cows. Magnusson (1923) first described C. equi (Rhodococcus equi) form suppurative pneumonia of a foal.

Properties of genus

1.   Morphology

Corynebacterium are gram positive, pleomorphic bacteria ranging from coccoid to filamentous rods. The size varies from 0.5-0.6 µm by 1.0- 3.0 µm. Some of the species appear as packets of parallel cells (palisade arrangement) or show ‘V’ shaped form (Chinese letter arrangement) in the microscopic field (Fig.1and Fig.2). The cell wall peptidoglycan contains meso-diaminopimelic acid (meso-DAP). The arabinose and galactose are major cell wall sugars. Short-chain mycolic acids (corynomycolic acids, 22–36 carbon atoms) are present. This kind of cell wall structure is impermeable to the hydrophilic compounds. However, the ‘porin’ present in the cell wall sometimes helps in import of the hydrophilic substances. Mycolic acid containing cell wall helps in intracellular survival within the macrophages. Corynebacterium is non acid fast, non-sporulating, non-capsulated and non-motile bacteria (except C. aquaticum)
.

Edmond Nocard (French Veterinarian) first isolated filamentous aerobic bacteria from clinical cases of ‘bovine farcy’ in 1888. In 1889, the genus Nocardia was formed by Trevisan, and the organism described by Nocard was named as Nocardia farcinica. In 1891 another similar organism (Nocardia asteroides) was isolated by Eppinger from a human brain abscess. Initially it was thought that they are the same organisms. Latter on the basis of the molecular studies their separate entity is established.

            However, 80 years later, re-examination of Nocard’s original isolate revealed two different filamentous organisms, one of which was Mycobacterium and the other was Nocardia. The cause of ‘bovine farcy’ has been subsequently attributed to Mycobacterium. Latter, it is proved that Mycobacterium farcinogenes is the actual causative agent of ‘bovine farcy’.

Dermatophilus congolensis was first described from clinical case of exudative dermatitis in cattle in Congo by Van Saceghem (Van Saceghem, 1915). It is primarily known as an animal pathogen causing acute, sub acute or chronic skin disease. The first cases of human infection with D. congolensis were reported in 1961 in four people who developed skin infection after handling an infected deer in a wildlife reserve in USA (Dean et al., 1961).

Properties of genus

1.   Morphology

Dermatophilus is a gram positive, non-acid fast, unusual bacterium having branched filaments. It follows a life cycle with different morphological features. It can be found in smears prepared from clinical samples in any form of its life cycle. Young filaments are 0.5 to 1.5 μm in diameter.  They enlarge within epidermis as they produce layers of transverse and longitudinal septations and reach 5 to 8 μm in diameter, surrounded by a mucoid capsule. The septations result in the formation of a sporangia (a kind of fungal fruiting body, sac like structure with spores) containing up to eight cocci cells. In the presence of liquid, the cocci are released and converted into flagellated motile zoospores, the infective form of the organism. It can infect the new site in the same animal or new host. These zoospores become visible in smear as parallel lines forming a ‘railway-track’ or ‘trum-track’ appearance (Fig.1). Under favourable conditions, the zoospores form germ tubes that develop into branching filaments. These filaments are the invasive form of the organism and the cycle is repeated.

Leptospira 

Antony Van Leeuwenhoek (1681) first observed the Spirochaetes under the microscope and described them. In 1833, Ehrenberg used the name Spirochaeta for free living spiral shaped organisms. Obermeir (1873) first described a Spirochaete of pathogenic significance isolated from human patients of relapsing fever. Inada et al. (1916) first isolated Leptospira icterohaemorrhagiae from human patients of Weil’s disease. In 1980, Nogochi proposed the name Leptospira.

      In India, Taylor and Goyale (1931) first reported Leptospira from human patients suffering from jaundice in Andaman Islands (Srivastava, 2006). Ayyar (1932) first reported Leptospira from dogs in Chennai city. 

Properties of genus

1. Morphology : Leptospira are gram negative, spiral shaped organisms with hooked ends. Length varies from 6-20 µm with 0.1-0.2 μm diameter (Fig.1). They have a typical double membrane covering. The cytoplasmic membrane and peptidoglycan cell wall are closely associated and are surrounded by an outer membrane. Two periplasmic flagella (endoflagella) are found within the cell and are responsible for the motility. No flagella are present as extracellular appendages. One end of the flagella is attached with the pole of the bacterial cell by insertion disc. Other end extends towards the centre of the cell and may overlap the flagella coming from the opposite end. The endoflagella consists of a solid inner core surrounded by tubular sheaths. The FlaA and FlaB proteins constitute these flagellar sheath and core, respectively.

Properties

1. Bacteroides, Dichelobacter and Fusobacterium are major gram negative anaerobes isolated from human and animals. Other gram negative anaerobes are listed below (Table-1).

       2.   They are tolerant to oxygen in comparison to strict anaerobes. They do not die after oxygen exposure

       3.         They naturally inhabit the intestine and mucosal surfaces of human and animals. Majority of them are opportunistic pathogens. Often they cause mixed bacterial infection along with aerobes. Aerobes remove oxygen and create an anaerobic condition favourable for their growth. Aerobes may also supply other growth requirements. For e.g. Porphyromonas asaccharolytica requires vitamin K for its growth, supplied by another bacterium, not the host.

The name Mycoplasma is originated from the Greek word mykes (fungus) and plasma (formed). It was first used by Albert Bernhard Frank, a German Biologist in 1889. He thought it was a fungus. An older name for Mycoplasma was Pleuropneumonia-Like Organisms (PPLO), referring to organisms similar to the causative agent of contagious bovine pleuropneumonia (CBPP). It was later found that the fungus-like growth pattern of M. mycoides is unique to that species. It was first isolated in 1898 by Edmond Nocard and E. Roux from bovine lungs. Whereas, Mycoplasma pneumoniae was considered as a virus previously. Eaton and his co-workers cultured the causative agent of human primary atypical pneumonia (PAP) or "walking pneumonia." It was known as "Eaton's agent." In the early 1960s, Leonard Hayflick, in Philadelphia, was first to isolate and cultivate the causative agent of primary atypical pneumonia and identified the agent as a Mycoplasma and named it Mycoplasma pneumoniae.

History of Rickettsial infections went back to 16^th century and it has long been associated with famine and war. Thus Rickettsial infections played a significant role in the history of Western civilization. Epidemic typhus had major impact to decide over the outcome of several wars. This epidemic alone killed or caused great suffering to over 100,000 people in the two World Wars.  However, the causative agent was not determined until the early part of the 20^th century. Rocky Mountain Spotted Fever (RMSF) was the first detected Rickettsial infection as early as in 1896 in Idaho Valley, USA.  It was originally known as ‘Black Measles’ because of its clinical appearance in the form of characteristic spotted rash appearance throughout the body of the patients. Howard Taylor Ricketts, an American pathologist for the first time described the causative agent of Rocky Mountain spotted fever and was able to isolate it in the laboratory animals during 1902-1909. He was a dedicated scientist and, on several occasions, injected himself with a pathogen for experiment. The causative pathogen of Rocky Mountain spotted fever, Rickettsia rickettsii was named after him. Later, the family Rickettsiaceae as well as the order Rickettsiales was named after him. Ernest William Goodpasture, an American pathologist and physician, invented the methods of isolation and culturing the rickettsial pathogens in chicken embryos and fertilized chicken eggs.

The word ‘chlamydia’ comes from the Greek word ‘chlamys’ which means, “cloak draped around the shoulder”. This describes how the intracytoplasmic inclusions caused by the bacterium are “draped” around the infected cell’s nucleus. Chlamydia was first discovered by a Czech zoologist and parasitologist, Stanislaus von Prowazek in 1907 in Berlin, but scientists believe it was actively infecting people for centuries before its discovery. Because the symptoms of Chlamydia are similar to some other infections it was not identified as a sexually transmitted disease. Originally, because of its structure it was thought to be a virus. In 1963 it was recognized as bacteria rather than a virus.

Properties of genus

           They are poorly stained by Gram’s stain. Chlamydiae are readily stained by Castaneda (blue in appearance), Giemnez and Macchiavello (red in appearance) methods. However, Giemsa staining is preferable to stain the inclusions (Chlamydial micro colony) in the cell culture. Inclusion bodies of the Chlamydiae are basophilic in nature. Again, the staining of the inclusion bodies may differ depending on the species. In C. trachomatis, the inclusion bodies contain glycogen matrix and can be easily stained with iodine solution.

Introduction to Swine Farming

World pig population in the year 2007 was 918,278,000 when the pig population in India was 14,000,000. The per head agricultural land holding is decreasing continuously because of a high rate of increase in population leading to excessive pressure on land. This lower land holding per person leads to lowered production per person forcing people to move to urban areas for better incomes. Excessive population pressure on urban areas itselves has its own demerits and limitations. To prevent this drift of village people to the urban areas they should be encouraged to adopt agriculture based professions which give the villagers a good return in short time span. Swine industry provides the same opportunities to villagers who can get better income with a minimal investment in short time intervals. In India for varied reasons the swine industry is not much developed. The breeds yield less and also the littre size is small in comparision to the better breeds available in many parts of world. In India, the desi swine survives on garbage and looks very unhygienic. Thus, most of the people in India feel uncomfortable to consume swine. Indian swine industry has a great potential but needs attention with respect to raising of better productive breeds with lesser cost for hygienic feeding and management.

            Pig is mainly reared for meat, skin and manure. Growing pigs for meat is little different from other production processes because here the daily live weight gain relates to the daily feed supply and the efficiency of output production depends upon the total quantity of input (feed).

(I)  Management of Swine

Since early days, cattle, sheep and goats accompanied human beings where ever they migrated but it is not the same with swine because of its rearing in unhygenic conditions. Some communities started avoiding swine because of the foul smell from pigs and slowly it entered into the religious life of Muslims and Yashdies.

            In China since 4900 BC and in England before 800 BC swine production scripts are found in majority in these two countries and at present these countries are leading in swine production. Swine growth is very much influenced by the method of keeping and rearing them and that is why its managemental practices should always be given high priority.

Reproduction

The female piglet attain maturity in 6-7 months of age and has a weight of 60-80 kgs. Males take more time to attain adolesence. The breedable age of a female is 8-12 months when it has a weight above 100 kgs. Its heat period is for 2-3 days. It may conceive by artificial insemination after 2-3 days of heat. The gestation length is 114 days. Weighing may be done after one month of age. Females generally give birth to 6-10 young ones at a time. If more young ones are born, than there are increased chances of death of the young ones.

(I)  Structure

The swine is an omnivorous animal because if can eat both vegelables and meat. But generally they prefer the vegetarian diet over the carnivorous diet. Pig is a simple stomach animal with double hoof. Different type of pigs are found as Sus indicus, Sus vittatus, Sus scrofa and  Suis domesticus.

            At the first instance, the skeleton of pig looks smaller than its original size. The main reason of this is feeding and nutrition of the animal. The pigs are kept indoor, provided less exercise and artificial feeding that leads to fattening of animals (pigs). The other reason for the undersized skeleton in pigs is that as compared to other animals the bone density of pig is more and they are very nicely arranged, that is why they are much stronger. The skull of the pig is triangular, long towards mouth, frontal bone is large and strong.

            The jaw has teeth, they use it for tearing and chewing of objects (feed). The temporary and permanent dental formula of pig is follows:

(I)  Breeds

Basically swine is a clean animal and in our country, mainly, poor people  are rearing them with the least available infrastructure and poor quality feed, usually garbage, and that is why swine  are forced to take garbage as a feed (Fig. 23). With good food and shelter, they can give birth twice a year with better productivity. Even 8000- 9000 years back swine stood at 3^rd position for being reared by humans after cattle and sheep. Swine comes under phylum Chordata as they have vertebral column and their class is mammalia. They come under Artiodactyla for being ungulate animals. Swine comes in Swede order and their species is swiss. They have 3 subspecies. The domesticated subspecies comes under Swede domesticus and wild pigs comes under Swede vitatus and Swede scrofa. In India there are 4 breeds of pigs. Wild, desi, exotic and crossbred.