eChapters

The most important property of a virus is its infectivity or ability to invade a cell and parasitize that cell to replicate itself. To measure infectivity, a titre is defined as the given number of infectious virus units/unit volume and an infectious unit is the smallest amount of virus that produces some recognizable effect in the host system. There are two basic types of infectivity assays (a) Quantal assays and (b) Quantitative assays.

Quantal assays do not measure the number of infectious virus particles present in the inoculum but denote a value for the virus titre where measurement is based on an all or none principle, CPE + or -, dead or alive etc. In the quantitative assays, the number of virus particles present in the suspension can be quantified.

The tentative diagnosis of viral diseases of livestock can be made by clinical symptoms alone. The clinical diagnosis is substantiated by the laboratory to obtain a precise, correct and prompt diagnosis. The success however depends on the collection of suitable materials in proper transport medium at a particular stage of disease condition and its dispatch to the laboratory in a manner that little or no alterations occurs in the specimen. This would facilitate the isolation and identification of the causative viral agents easily.

Bovine
 
1.    PPR    Eye, mouth, rectal swab in PBS on ice, 10 ml blood  in anti-coagulant at height of temperature, Prescapular lymph node, spleen, piece of intestine on ice, lung, liver, spleen, tonsil in 10% neutral formol saline solution.

Processing

On arrival in the laboratory, the specimens are processed immediately or refrigerated until processed. For inoculation into animal/cell culture/embryonated eggs (EE), swabs are shaken in fluid medium, faeces are dispersed in fluid medium and tissue specimens are homogenized in a high speed blender/pestle and mortar with the help of an abrasive like powdered glass or sand. Good quality hard sand should be properly washed in distilled water, treated with HCl, washed thoroughly, dried and sterilized before use. Generally the infective tissue is homogenized in a few ml of buffer usually having a pH of 7.2 to 7.3 to make about 10% tissue suspension. The suspension is centrifuged at about 1000g for 10-15 minutes to sediment the tissue debris and coarse materials.

Principle

The infectivity of a virus may be neutralized by specific antibody when they are mixed and incubated. In some cases, the addition of homologous or guinea pig complement to the mixture enhances neutralization, particularly when early antiserum is used. Serum must be inactivated by heating at 560C for 30 minutes to inactivate complement or to remove non-specific virus inhibitors. Serum-virus mixtures are inoculated into appropriate cell cultures, which are then incubated until the only virus controls develop cytopathic effects. Antibody by neutralizing the infectivity of the virus, protects the cells against virus destruction.

Early and accurate diagnosis of disease is of prime importance for both the successful treatment of the patient and in limiting the spread of disease in the community. It is in this context that immunodiagnostic methods are now being used extensively since they can be extremely sensitive and highly specific. Among the most successful methods are those utilizing labelled antibodies or antigens. Examples of these are immunofluorescence in which antibodies labelled with fluorescent dyes are utilized and radioimmunoassay in which antigens or antibodies are labeled with isotopes. Both of these procedures have proved to be of great value for particular purposes.

Precautions to be taken while working in the laboratory for personal safety and to prevent any hazards.
    1.    Be vaccinated against dangerous viruses viz., rabies and hepatitis B as persons can contract infection while working with these organisms.
    2.    Use eye protection viz., goggles, spectacles etc to avoid splashing microbes into the eyes. 
    3.    Do not rub eyes with contaminated hands or objects.
    4.    Do not eat or drink anything in the microbiology laboratory as it will contaminate the laboratory.

Introduction and History

Leguminosae/Fabaceae is a superfamily of dicotyledonous plants, which in species diversity is the third largest family of plants accounting for 5% of Earth’s plant biodiversity and make up for more than at least 1% of the total Earth plant biomass. Among these, legume grains and pulses having more than 20 to 30% lysine protein content are cultivated in 145 million ha of land in developing countries. This family is also characterized by presence of specialized tumor like structure formation (nodules) on roots (occasionally on stem as in Sesbania rostrata, Aeschynomene) that is inhabited by microsymbiont gram-negative bacteria (Rhizobium), engaged in fixing atmospheric nitrogen or symbiotic biological nitrogen fixation.

Introduction

Rhizobia and Frankia are soil bacteria that exhibit symbiosis with their particular hosts owing to their ability to understand the intricate signals excreted by the host roots. Rhizobia exhibit symbiosis with legumes and one species member of Ulmaceae family Parasponia andersonii while actinomycetes Frankia forms the group of nitrogen-fixing bacteria that live in symbiosis with a large spectrum of dicot plants distributed among eight families consisting of over 24 genera and around 200 species of angiosperms (Benson and Silvester, 1993) and are collectively responsible for 15% of the biologically fixed nitrogen in the world. This Frankia-woody tree or dicotyledonous plant interaction results in evolution of the actinorhizal plants and the symbiotic interaction is described between Frankia (actino) and plant roots (rhiza).

Introduction

Nitrogen-fixing cyanobacteria are the group of most primitive prokaryotes that have been observed in proterozoic era. Many Proterozoic oil deposits are attributed to the activity of Cyanobacteria, such as Gloeocapsomorpha. Small concentrically layered structures called pisolites are also the result of fossilized bacteria.

Introduction

Diazotrophs are phylogenetically diverse microbes spanning over various classes varying vastly on basis of physiological properties (Young, 1992), include various phototrophic microorganisms aerobic phototrophic Cyanobacteria (Vaishampayan et al, 2001), anaerobic purple-sulfur phototrophs like Chromatium, and green-sulfur phototrophs, e.g. Chlorobium, Rhodopseudomonas; chemolithotrophs Alcaligenes, Thiobacillus, Methanosarcina, Methanobacterium, Desulfovibrio or Azospirillum lipoferum and heterotrophic bacterial anaerobes (Clostridium), microaerophiles (Herbaspirillum), and aerobes (Azotobacter). Free-living aerobic nitrogen fixing bacterial genera found in soil include obligate aerobes as Azotobacter, Beijerinckia, Derxia, Achromobacter, Mycobacterium, Arthrobacter and Bacillus but the majority are microaerophilic (e.g. Azospirillum, Herbaspirillum) or facultative and obligate anaerobes (e.g. Klebsiella, Aerobacter, Desulfovibrios, Rhodospirillum, Clostridium, Erwinia).

Introduction

Increased population pressure, reduced length of fallow, deforestation and improper agricultural practices have led to widespread soil degradation in many parts of the developing world which has culminated in appearance of determinative manifestations of environmental damage in form of inadequate replenishment of soil nutrients and organic matter. Phosphorus is second major plant growth limiting nutrient and despite being in abundance in soil (organic and inorganic form), P deficiency is becoming critical in many soils throughout world as these soils have free available P concentration (generally) not higher than 10mM even at most soluble slight acidic pH (Arnou, 1953). Moreover, consistent P deficiency threatens to disturb the use efficiency of applying other nutrients. Hence to preserve the sustainability of agriculture it is foremost to rebuild soil fertility and maintain/improve the soil biodiversity to reap hiked current levels of productivity and farm income.

Introduction

Lithosphere, including the earth’s crust, is helpful in providing the base or medium for sustenance of most life processes and forms, interwoven in fine network interdependencies within themselves and the environment surrounding them i.e. ecosystems. Terrestrial ecosystem contains an important dynamic living matrix termed soil, which is critical for agricultural production and food security. Soil forms the medium for growth and maintenance of a variety of plant species while the plant roots in the soil represent a four dimensional region in space and time of profuse activity relative to the bulk soil, revolving around pH, nutrient, redox potential, and exudate gradients changing as distance from the root increases (Marschner, 1995). The soil region adhering the plant roots is being strongly influenced by the presence of these roots and is characterized by high rates of microbial population and activity and referred as rhizosphere (the soil adhering to plant roots).

Introduction

Vesicular arbuscular mycorrhizae are fungi that exhibit symbiosis with roots of higher plants. The term vesicular arbuscular is derived from characteristic structure i.e. ‘branched hyphae or arbuscles’ that are formed with in the root cortical cells and vesicles or ‘swollen lipid storing organs’ that occur with in or between them.

Introduction

India being a developing nation is trying to reach a balance in ever increasing population with marginal increase in crop production. There occurred a bigbang in crop production during the green revolution era however this also resulted in creation of infertile, barren lands with low chemical nutrient input responsive soils. Soil fertility is the major constraint among resource poor Indian farmers as lesser benefits are harnessed by use of newer agricultural protocols/tools/products viz improved varieties, productive technology from less fertile soils. There is dire need for looking for the alternative technologies of food or crop production to satiate the hunger of burgeoning Indian population. Today there is enormous emphasis on the conservation facets of soil fertility and crop productivity which are the instrumental philosophies in sustainable agriculture. Biofertilizers are the cost effective, ecofriendly and renewable resource of plant nutrients that could well supplement the use of already functional and popular chemical fertilizers for obtaining increase in crop yield without over hazardous impacts on various facets of soil chemistry, fertility and microbial diversity to attain sustainable agricultural system.

Introduction

Introduction of improved high yielding varieties of crop plants, use of modern agricultural practices coupled with essential control of pests of food and fiber crops have significantly contributed towards increasing the food production in green revolution era in India. Pesticide application forms the foremost limb in hiked agricultural food production and management practices. The production and post production management of crop yield requires increased use of pesticides.

Introduction

Soil forms the base of the lithosphere on earth and is a fundamental and irreplaceable versatile three dimensional dynamic system that supports majority of terrestrial plant and animal life on earth. This soil system contains mineral (sand, slit and clay forming basic soil structure) and organic matter as well as marginal air and water contents. The soil organic matter content of the soil system constitutes every fraction of matter in various stages of decomposition that once was associated with the body, body parts, exudates, tissues and cells of living organisms including plants, animals and microorganisms. It is the product of continuous cycling of the compounds synthesized by autotrophic plants among the three kingdoms viz microbes, plants and animals. The decomposition of the organic residues in soil is performed primarily by the resident soil microflora termed as microbial decomposers; though initially the larger and complex organic material is broken down, devoured upon, chewed, regurgitated and transformed into smaller bits by larger soil faunal forms (earthworms, beetles, springtails, and collembola, the macro (large) to mesofauna) on which soil microbial forms could act upon.

Introduction

Bioremediation can be defined as elimination, attenuation or transformation of polluting or contaminating substances by the use of biological processes, to minimize the risk to human health and the environment. Bioremediation of contaminated soil and water uses microbes (e.g. bacteria and fungi) to convert pollutants to harmless or more environmentally acceptable products and minimizes the risk to human health in a natural or managed process.

Climate change and variability are concerns of humankind. The recurrent drought and desertification threaten seriously the livelihood of over 1.2 billion people who depend on land for most of their needs. The global economy has adversely been influenced due to droughts and floods, cold and heat waves, forest fires, landslips and mudslips, icestorms, duststorms, hailstorms, thunder clouds associated with lightning and the sea level rise (Fig. 1). The year 1998 was the warmest and declared as the weather related disaster year, which caused hurricane havoc in Central America and floods in China, India and Bangladesh. Canada and New England in the U.S suffered heavily due to icestorm in January while Turkey, Argentina and Paraguay with floods in June 1998. In contrast, huge crop losses were noticed in Maharashtra (India) due to unseasonal and poor distribution of rainfall during 1997-98. The 1997/1998 El Nino event, the strongest of the last century affected 110 million people and costed the global economy nearly US$ 100 billion. A string of 16 consecutive months saw record high global mean temperature in 1997-98.

1. Introduction
 
The bryophytes are found everywhere in the world except in the sea. They grow on wet soil or rock, the trunk of trees, in lake, river and even in Antarctic island. The bryophytes are placed taxonomically between algae (Fig. 1) and pteridophytes (Fig. 2); there are about 24,000 species in the world. They are further divided into three phyla, Bryophyta (mosses 14,000 species, Fig. 3), Marchantiophyta (liverworts 6,000 species, Fig.4a,b) and Anthocerotophyta (hornworts 300 species, Fig. 5). They are considered to be the oldest terrestrial plants, although no strong scientific evidence for this has appeared in the literature. This hypothesis was mainly based on the resemblance of the present-day liverworts to the first land plant fossils, the spores of which date back to almost 500 million years. Among the bryophytes almost all liverworts possess beautiful cellular oil bodies (Fig. 6) which are peculiar, membrane-bound cell organelles which consist of ethereal terpenoids and aromatic oils suspended in carbohydrates- or protein-rich matrix, while the other two phyla do not. These oil bodies are very important biological markers for the taxonomy in the Marchantiophyta (Asakawa, 1982, 1995; Asakawa et al., 1979b, 2008c, 2012b, 2013a,b; Asakawa and Ludwiczuk, 2008a,b; Ludwiczuk and Asakawa, 2010).

Halophytes are salt-resistant or salt-tolerant plants which thrive and complete their life cycles in terrestrial or aquatic habitats having high salt concentrations. Aronson (1989) compiled a partial list of halophytes containing 1560 species in 550 genera and 117 families. Menzel and Lieth (1999) listed as many as 2600 plants under salt tolerant flora. Although halophytes represent only 2% of terrestrial plant species, they are present in about half the higher plant families and represent a wide diversity of plant forms. Because of their diversity, halophytes are regarded as a rich source of potential new crops. Halophytes are tested as vegetables, fodder and oilseed crops under field trials. The oilseed halophyte, Salicornia bigelovii, yields 2 tones/ha of seed containing 28% oil and 31% protein, similar to soybean yield and seed quality.

Nowadays, revolutionary changes in entire globe have led to the economic, cultural and scientific development in our society and have augmented considerable changes in our food habits and life-style. Continuously growing population had noticeably increased the pressure on land, water and energy resources. All these resources are scarce and going to be exhausted in coming decades at the present rate of consumption. Undoubtedly, production of food is more imperative than the production of energy or any other bioproducts. Moreover, with the world population rising to 9 Billion in 2050, with many inspiring to a western life style and diet, this challenge should be addressed urgently (Draismaa et al., 2013). The challenge to produce about 70% more food by 2050 for a growing and increasingly affluent world population has motivated several review papers addressing the different dimensions of the food system and food security (Verburg et al., 2013). Presently, human beings consume approximately 2.5 billion tons of dry weight of harvested crops which include approximately 2.3 billion tons of cereals (e.g., rice, wheat, and corn kernels) and grass from managed pastures (Smil, 2000).

Ever since the dawn of civilization, dependence on plants has been indispensable for human survival. Transformation from food gathering to settled agriculture necessitated domestication of plant species useful for mankind leading to co-evolution of plants and man in absolute harmony with nature. Natural disasters like famines, floods, epidemics have often led people to search new plant species for human consumption. Out of an estimated total of 80,000 plants of possible economic use, about 30,000 plants have been found to be edible in nature and approximately 7,000 plants have been cultivated by mankind at one time or the other, of which only 158 plants are widely used for food (Wilson, 1992). Among these, 30 crops provide 90% of the world’s food and only 10 crops supply 75% of the world’s food budget. Out of the above only three crops, rice, wheat and maize provide 60% of the world’s total food requirement (Paroda, 2000). This dangerously narrow level of food base may imperil the existence of mankind during a time of impending crisis in unforeseen times in the future.

Wild edible plants have played an important role in human life since time immemorial. People depend on the wild plant resources for various purposes like fire wood, timber, non-timber forest products, medicines and food (Pushpangadan, 1995). In many cases, rural communities depend on wild edible plants, to meet their food needs in periods of food shortage. Indian subcontinent is blessed with varied and diverse soil and climate conditions suitable for the growth of various plant species. It has been estimated that 9000 of the 15,000 higher plants occurring in India are commercially useful. Of these 7500 are medicinal, 3900 are edible, 700 are culturally important, 525 are used for fiber, 400 are fodder, 300 for pesticides and insecticides, 300 for gum, resin and dye and 100 for incense and perfume (Anonymous, 1992-1993).

The palmyrah palm exists both in the wild as well as in cultivation, ranging from sea level about 800 amsl. It is usually grown in seasonal tropical or subtropical climates on sandy soils. It is a very adaptable palm, however, growing well in dry areas and is quite drought resistant. It also grows in per-humid areas and survives water logging quite well. The worldwide distribution of natural and cultivated populations of the palmyrah shows that it occupies a band on either side of the equator and extends laterally over a considerable girth. The country wise distribution of the palms are Mauritania, Senegal, Mali, Gambia, Guinea-Bissau, Guinea, Ivory Coast, Upper Volta, Nigeria, Gaban, Congo, Sudan, Tanzania, Madagascar, Saudi Arabia, Iraq, Iran, Pakistan, Bangladesh, Sri Lanka, Myanmar (Lubeigt, 1977), Thailand, Cambodia, Malaysia and Indonesia (Kovoor, 1983). In India, the palms are wide spread in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Maharashtra, Odisha, Madhya Pradesh, Bihar and West Bengal.  Isolated patches are also seen in Assam, Gujarat and Uttar Pradesh (Anonymous, 1948). The palmyrah is considered as a slow grower and the growth rate decreases in regions of higher altitude (Tjitrosoepomo and Pudjoarinto, 1982).

The Indian Himalayan region is a well known abode to numerous plants of medicinal significance. The Western Himalayan ranges are home to a diverse flora of variety of endemic medicinal plants making it a biodiversity-rich region (Samant et al., 1998).  The ancient system of traditional medicines has been using these endemic medicinal plants since time immemorial. Of late the resurgence of herbal system of medication has led to an unprecedented rise in extraction of such plants from the wild for medical preparations. Most of the times the plant collection is unscientific and unthoughtful of ecological status of the medicinal plant, especially herbs. As a result, unplanned collection and other human interferences have brought a threat to survival of several important medicinal plants of the IHR an  example being  Brahmakamal.

Tropical root and tuber crops are the third important group of food crops after cereals and pulses. Tuber crops hold a premier position among food crops in the tropical and subtropical regions of the world. These crops are rich in starch and calories and have great potential in meeting the food and energy needs.  More than 840 million people do not have enough food to meet their basic daily energy needs. Far more - an estimated 3 billion - suffer the insidious effects of micronutrient deficiencies leading to hidden hunger. Apart from its popular use as food, tubers also find an important space in cattle feed and agro industries sector.Tropical tuber crops possess high photosynthetic ability coupled with the capacity to yield under marginal lands, adverse biotic and abiotic stress etc (Ravindran et al., 2008).

Dragon fruit, commonly known as pitaya/pitahya (Hylocereus sp.) is a  climbing perennial cacti belonging to the Cactaceae family and the subfamily Cactoidea of the tribe Cactea (Raveh et al., 1993). It is a perennial climbing cactus plant native to tropical areas of North, Central and South America. Main countries growing dragon fruit are Vietnam, Colombia, Mexico, Costa Rica, Nicaragua, Thailand and Taiwan. Cultivation also occurs in Australia, Israel and Reunion Island. The European Union and Asia, especially China are the largest import markets of dragon fruits (Vinas et al., 2012).

Broad dhaniya (Eryngium foetidum L.: Umbelliferae - Apiaceae) is an underutilized leafy vegetable and aromatic plant used for seasoning food items and source of medicine. It is a shade loving plant of tropical regions.  It has got status of a promising cash crop with huge export potential particularly in United Kingdom, USA and Middle East markets. Its medicinal and seasoning properties are well known in various countries like Vietnam, India and in the Amazon region (De Gumao et al., 2002). Broad dhaniya is relatively unknown in many other parts of the world and is often mistaken and misnamed for its close relative Coriander (Coriandrum sativum L.).

Black caraway (Bunium persicum Boiss. Fedtsch ) commonly known as kala zeera is a low volume,  high value, under-exploited and  non-perishable crop that finds place  in cold arid  North -Western Himalayan regions of Indian sub-continent. Its fruits are expensive spice and are used in indigenous system of medicine for curing various ailments and disorders. The proper information on botanical identity of the species, its description and distribution, active ingredients, standardized agro-techniques, processing and value addition and marketing potentials, etc. are very scanty. An attempt has been made to gather information on various aspects of kala zeera to promote its cultivation in the cold arid regions of the Himalayan states and its role in improving the socio-economic conditions of the people by cultivating the cash crop.

Dyes are one of the most important by products of the plants, as they are related with cultural practices, rituals, arts and crafts, fabrics and to satisfy personal embodiment. However, dye yielding plants have not received significant attention (Grover and Patni, 2011). Dye is a substance that has affinity to the substrate to which it is being applied such as textile fibers, foodstuffs and powder. They are organic coloured substances which absorb light in the visible part of the spectrum and have the property of colouring the substrate they are applied to.
 
Colourants which are obtained from plants and natural sources are known as natural dyes. Natural dyes have been traditionally used in most of the countries. These dyes were obtained from roots, leaves and bark (Akhtar et al., 2012). Natural dyes find use in the colouring of textiles, drugs, cosmetics, etc. Owing to their non-toxic effects, they are also used for colouring various food products. In India, there are more than 450 plants that can yield dyes (Siva, 2007).

Kale (Brassica oleracea L. convar. acephala (DC.) Alef.) is a representative of cole group of vegetables and cool-season cooking green somewhat similar to collard and non heading cabbage that has gained recent widespread attention due to its health-promoting, sulfur-containing phytonutrients. Kale is grown for its large foliage which is mainly used as leafy vegetable. This leafy vegetable is helpful in reducing the chances of cancer if taken regularly. Among the vegetable crops, kale is the richest source of carotenoids which is the precursor of vitamin-A. Besides, it also contains good amount of different minerals essential for human diet. There are several varieties of kale, all of which differ in taste, texture and appearance.

Gingers  belong to Zingiberaceae family and are made up of about 1000 species in 47 genera. They have numerous members with aromatic oils that have made them popular for perfumes and ornamentals. Ornamental gingers, while related to edibles, are usually grown for their looks instead of their flavor. A very large and diverse group of gingers are valued both for their tropical foliage and for their large, colorful flower heads. From the startling red ginger to the subtle shell ginger, these attractive plants are easy to grow in home landscapes in tropical and semi-tropical areas. They are great for tub gardens They can be very rewarding to grow, and with some simple care will continue to produce beautiful leaves and flowers for many years which also have cut flower value.

The edible speciality mushrooms are mushrooms that are generally not grown and available commonly in the market. Any mushroom other than popularly grown white button mushroom (Agaricus bisporus) falls under the specialty category, and these mushrooms are generally not available over the counter or in departmental stores in India or other countries in the world. The mushrooms under this group include the different types of commonly grown Oyster mushrooms like grey, black, white, pink, yellow oyster mushrooms, King Oyster mushroom, Shiitake mushroom, Black Ear mushroom, Shimeji mushroom, Enokutake mushroom, Milky mushroom, the Portabella brown, Cremini mushroom , Straw mushrooms and others. This paper will describe in detail biology and cultivation of these mushrooms as grown under controlled environment conditions or under seasonal growing conditions, where ever possible.

Mizoram in North East India, is located between 21º58’ to 23º35’ N latitude and 92º15’ to 93º29’ E longitude, surrounded by Tripura, Assam and Manipur in North frontier regions; Bangladesh in west; and Mayanmar in east and south. The undulated topography of Mizoram, known as Lushai hills during British period, has varied altitudes ranging from 21 to 2157 m above mean sea level, annual rainfall of 2000-3200 mm, and mean monthly temperature of summer (monsoon) ranges from 14.6ºC to 29.6ºC. Besides having good rainfall; the vegetable production, including leaf vegetables, during winter period is limited by acute soil moisture stress caused by high rate of evapo-transpiration, almost no rain from November-March, non-availability of irrigation water and low water holding capacity of the sloppy land (Singh et al., 2011; Singh et al., 2013b).

The purpose of the clinical examination is to identify the clinical abnormalities that are present and the risk factors that determine the occurrence of the disease in the individual or population. The focal point of any investigation of animal disease is the making of diagnosis and the critical part in making that decision is the clinical examination of the animal or group of animals. Without a proficient clinical examination and an accurate diagnosis it is unlikely that the treatment, control, prognosis and welfare of animals will be optimized.  The level of examination set out is sufficient to enable the clinician to determine the nature of the abnormality and the system involved.

Metabolic profile testing (MPT) refers to the use of a battery of tests for the diagnosis of subclinical nutritional and metabolic disease in dairy cows on a herd basis. Typically, blood samples from 5-7 animals per production group are tested for various analytes. MPT is most useful in the diagnosis and management of periparturient disease. Specific nutrient imbalances, either deficiency or excess, in the diet of late-gestation cows have been related to increased prevalence of milk fever, hypomagnesemia, retained placentas, downer cow syndrome, mastitis, udder edema, ketosis, hepatic lipidosis, and displaced abomasums.

Examination of rumen fluid was introduced for clinical diagnosis during the 1950’s. The stomach of ruminant harbor beneficial microbes required for digestion of feed consumed. Stomach maintains an ideal environment (pH 6.8 to 7.2 and temperature 39-40°C) for growth and proliferation of these microfloras. In any of the ruminal disorder this homeostasis get upset resulting in shifting of microbial population (Gram negative to Gram positive) and formation and accumulation of toxic products of abnormal metabolism. This further leads to an array of pathologic process in the body. Hence physical, microbial and biochemical examination of rumen fluid can be considered as an important diagnostic tool for wide variety of disorders.

The main aim of blood testing is to ascertain the adequacy of each new diet in relation to the herd’s requirements, i.e. what the cows think of their rations. So blood sampling should be carried out as soon as possible after major changes in dietary constituents. But two weeks must elapse after the changes to allow the rumen to become fully adapted. The metabolic profile is based on the concept that the laboratory measurement of certain components of the blood will reflect the nutritional status of the animal with or without the manifestation of clinical abnormalities. The values of Hb, PCV, TEC, TLC, DLC and erythrocytic indices are useful indicator of health status of the animal.

Carbohydrates are constituents of all living cells. Animal as well as plant cells use carbohydrates as source of energy. Blood glucose is a useful indicator of energy metabolism and fertility status. Under certain clinical circumstances, estimation of carbohydrates becomes essential. Sugar levels (particularly glucose) in blood or urine are used as an important parameter for diagnosis of ketosis and diabetes mellitus.

The glucose is utilized in the body for immediate energy requirements. The utilization of glucose depends on the integrated activity of digestive system metabolism and endocrine system of the body. Glucose tolerance is referred as the capacity of animal to regulate elevated blood glucose on ingestion or infusion, gradually. The level of glucose that can be tolerated by an animal without producing glucosurea is indicative of tolerance. Glucose load challenges the pancreas to release insulin which in turn regulates blood glucose level. If the insulin release is adequate and target cells have healthy receptors, elevated blood glucose level return to base value within 2 hours and glucose does not appear in urine. An increased glucose tolerance means limited rise and rapid fall in blood glucose in short span than the normal rate of utilization.

Urea is the detoxification product of the ammonia derived from the deamination of amino acids. Urea is therefore the most common nitrogen-containing end product of protein catabolism. Its synthesis from ammonia occurs in the liver (via the urea cycle), and it is then excreted by the kidneys. The concentration of urea inside red cells is slightly less than in plasma due to the presence of large amounts of hemoglobin inside the cells. Whole blood urea concentration is therefore slightly less than plasma (or serum) urea. Therefore, usually serum is used instead of whole blood for the determination of urea. The familiar term BUN (blood urea nitrogen) persists in spite of the fact that it is serum urea nitrogen which is usually measured.

The levels of calcium (Ca), inorganic phosphorus (P) and magnesium (Mg) may help in early diagnosis of metabolic and deficiency disorders and for monitoring the herd health status of dairy cattle to maintain production and reproduction.

Estimation of Serum calcium

Calcium is present in 2 forms – inorganic and organic forms. Most of the functions of the calcium depend upon the ionized form. For estimation of serum calcium the most commonly used method is Clark and Collip method.

Sodium and potassium are the most important electrolytes of the body fluid. The sodium as sodium chloride is contained in body fluids. The potassium is also essential in body fluids and its concentration is controlled by the kidneys. The estimation of sodium-potassium balance makes an important contribution as component of metabolic profile test. Low level of Na occurs in early lactation of low grazing on summer pasture and also increasing age, depraved appetite, polydipsia and polyurea.

Total protein: (Biuret method)

There are several methods of estimating protein, in food, agricultural and clinical samples, each of them varying in sensitivity and applicability.

Principle
Biuret method is highly specific for protein and is based on the formation of the blue peptide-copper complex in alkaline solution. It is a method of choice in the clinical laboratory because of the simplicity accuracy and precision. The major limitation of the method is its poor sensitivity for many dilute solutions. The principle of this method is that the peptide bonds in protein react with biuret reagent to give a violet colored complex known as cupric potassium biuret. The colour intensity of which is proportional to protein concentration.

Trace minerals have long been identified as essential components in the diets of domestic livestock species. Trace minerals exist in cells and tissues of the animal body in a variety of chemical combinations, and in characteristic concentrations, depending on the trace mineral consumed and the tissue in which it is metabolized. Concentrations of trace minerals must be maintained within narrow limits if the functional and structural integrity of the tissue is to be maintained and the growth, health, and productivity of the animal are to remain unimpaired. Minerals are as vital to cattle as grass, water or air.

The concentration of essential elements must be maintained within quite narrow limits if the growth, health and productivity of the animal are to be maintained. Soil-plant-animal relationship is based on micro-mineral profile in animal blood, plant (fodder) and the soil is of paramount importance to identify dietary requirements of animals maintained under different husbandry practices of various agro-climatic zones. The soil occupies a strategic position in the chain of nutrition flow to plant, animal and eventually to man. The soil is the principal source of trace elements entering the food chain. The influence of the chemical composition of soil on the trace element contents of pant is well known.

Increased ketone bodies level in blood, known as ketonemia and condition is ketosis. The disease respond readily to treatment with glucogenic substances which can be one of the test therapy to differentiate this condition from milk fever and hypomagnesemia. The efficacy of this therapy can be estimates through estimation.

Collection of blood samples

Collection of blood sample is already discussed in exercise no. 4.

The daily nutrient requirements of animals varies for various stages of life i.e. maintenance ration, growing, working, pregnant, lactating, dry and diseased animals ration. Maintenance ration contains the vitamins and mineral only for life without any other production, while during pregnancy and lactation their requirements changed drastically from the maintenance ration. If not supply the standard amount of vitamins and minerals during these stages may disturb the metabolism and ultimately cause the production or metabolic disease. Therefore, the proper and sufficient (as per standard requirements) supplementation of vitamins and minerals can help in the prevention and control of production diseases in livestock.

Transfusion therapy is basically an attempt to replace blood or its components when the life is threatened. Blood transfusion plays a life saving role in general mostly to shorten the recovery time during any severe blood loss conditions arising due to accidents, major surgical interference, haemoprotozoan diseases especially in canines during anaemic conditions due to sever helminthic infestions, tick infectation, haemophilia etc.

In livestock, diversity of blood and lack of commercially available blood typing reagents, make blood group matching and typing difficult, which results in reduced importance in veterinary practice. Blood or individual blood component is to be transferred during the following conditions-