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When a metal M is immersed in a solution containing its own ion Mⁿ⁺, then  an electrode potential  develops. The value of  the  electrode potential  is given by the Nernst equation.

Goats are valued as economical milk producer and main source for meat for a large section of population. The dry matter intake varies from 3% (Meat goat) to 4-6% (Dairy goat) in different breeds of India and it is higher than that of larger farm animals.

1. Nutrient requirements for maintenance

Adult body weight of goats may vary from 15 to 45 kg in different breeds. There are also does and bucks that weight up to 60kg. Nutrient requirements for maintenance of adult goats are, therefore given for body weights ranging from 15 to 60 kg. On an average for maintenance 76 g DM is required for each kg of metabolic body weight and similarly the requirements for DCP and TDN is 3 and 30 g, respectively.

2. Nutrient requirements for pregnant does

Since adult body weight as indicated already varies from 15 to 60 kg, the requirements for pregnant does are also given for body weights ranging from 15 to 60 kg.

The availability of a plant pathogens in given area presupposes its ability to survive not only during its parasitic relations with hosts but also during those seasons in which the hosts are not growing. The latter part of continued existence of plant pathogens in which they remain in dormant condition to overcome the unfavourable condition of non availability of hosts is called “survival”. Pathogens may survive between crop seasons by means of specialized resting structures, by functioning as saprophyte in or on the soil or in diseased plant debris, or by living insome intimate association withlivingplants or otherorganism.

Modes of Survival: The modes of survival of plant pathogens are described below:

1. Parasitic Survival

Organisms, parasitic on perennial plants (fruits, plantation and forest trees) survive in or on their hosts actively or passively depending on the environmental conditions. Certain bacterial pathogens viz, X. campestris pv citri, X. campestris pv jugalandis, X. campestris pv. Pruni and Erwinia amylovora are known to be carried over perennially in holdover cankers or blighted twigs, which may produce bacterial ooze in favourable weather to fresh inoculums. Similarly several fungal plant pathogens like Colletotrichum gloeosporioides (anthracnose of mango), Oidium mangiferae (powdery mildew of mango), Podosphaera leucotricha (powdery mildew of apple), etc survive on infected organs of the plants. Along with cultivated crops, several undesirable plant (weeds, etc) both annual and perennial, grow independently in the nature. Such plants which belong to the same botanical family to which cultivated hosts belong , are known as collateral hosts. Some important examples include the survival of three Puccinia spp. causing wheat rusts in Indian subcontinent . These fungi survive in active sporulating stage on wild species of Triticum, Aegilops, Horedeum and Agropyron repens. Similarly, Rice tungro virus survive actively on Oryza spp., Echinocloa spp. and Leersia hexandra .

Description of important spices and condiments

Introduction

Studies on biocontrol agents have revealed the presence of a diverse range of antifungal metabolites derived from amino acid, polyketones and isoprenoid biosynthetic pathways, each of which has distinctive regulatory points and is subjected to different stimuli within organisms. In this experiment, the extraction of secondary metabolites from the culture of T. viride and Chaetomium globosum will be demonstrated.

The application of insecticide to control a particular crop pest should have options of the pesticides, as some may be less effective than other due to various reasons.

Aim: Perform the parallel operation of single-phase transformer and observe the load sharing of each transformer.

A power transformer is one of the most vital and an equally expensive component in a power system. It may so happen that, over time, due to load growth in its service area, an existing transformer may not be able to withstand the demand during peak-hours without exceeding its long-term MVA rating. Operating a transformer in such a fashion would cause overheating and degrade its expected life. In most cases, instead of commissioning an entirely new higher capacity unit, a more viable alternative exists in adding a smaller unit in parallel to complement the existing one. In other words, a new smaller capacity transformer can now be connected in parallel to the existing one such that the two shares a large peak load in a specific proportion and the one operating near limits is relieved of the burden.

Cancer has gained considerable relevance in companion animals nowadays owing to the increased awareness among the people towards animal sufferings and pain. A proper diagnosis augments a better treatment regime for the suffering animal. Of all species, dog develops cancer twice as frequently as humans. Mammary tumours rank second (behind skin tumors) as the most common neoplasm in dogs but constituting more than 50% tumours in bitches. All suspected growths therefore requires careful appraisal lest it be cancerous. Diagnosis of cancer represents one of the major challenges faced by the small animal veterinarian. In majority of instances, the differentiation of a benign from the malignant tumour can be made morphologically with considerable certainty and for the same, histopathological examination remains the gold standard. A proper histopathological diagnosis however depends a lot on the collection, fixation and processing of tissues. So clinician as well as histopathologist has their own role to play in the final diagnosis of cancer in animals.

Immunoassays rely on the ability of an antibody to recognize and bind a specific macromolecule in what might be a complex mixture of macromolecules. In immunology the particular macromolecule bound by an antibody is referred to as an antigen and the area on an antigen to which the antibody binds is called an epitope.

In some cases an immunoassay may use an antigen to detect for the presence of antibodies, which recognize that antigen, in a solution. In other words, in some immunoassays, the analyte may be an antibody rather than an antigen.

Description of important medicinal plants

Entomopathogenic nematode (EPN) viz., Heterorhabditis, Neosteinernema and Steinernema have been recovered from many regions of the world. They selectively infect many insects and a few other arthropods but do not adversely affect mammals or plants. They are actually vectors of pathogenic bacteria, cause relatively rapid death of the host (24 – 48 h) and show considerable potential in biological control of insect pests in the integrated pest management systems.

EPNs are similar to insect parasitoids in that the immature form develops at the expense of one host individual; they are ecologically similar to both parasitoids and arthropod predators because the host individually killed. However, these nematodes differ from predators and parasitoids in two ways: (1) the nematode is mutualistically associated with a bacterial pathogen which actually kills the host, and (2) the pathogenicity of the bacterium has a great influence on the efficacy of the system (Ehler, 1990). The purpose of this chapter is to introduce EPN as biocontrol agents in this refresher course and to provide an overview of some current issues in biological control of insects with particular emphasis on their relevance to the use of EPNs.

Biological control is defined as the action of natural enemies which maintains a host population at levels lower than would occur in the absence of the enemies. Natural enemies will include parasitoids, predators, nematodes, microbial pathogens and their gene products. Entomologists generally divide biological control into two categories: (1) natural biological control which is effected by native or coevolved natural enemies in the native home (origin) of a given insect and (2) applied biological control which due to human intervention. Applied biological control is further divided into classical biological control (introduction of exotic natural enemies) and augmentative biological control (enhancement of natural enemies already in place).

The term “plant health” has two overlapping meanings. In the more specific meaning, plant health refers to plant quarantine, while in the less specific use, it covers all areas of plant protection, such as plant pest management, plant quarantine, and pesticide regulation and application.

Class- Arachnida
 •Class Arachnida includes scorpions, spiders, ticks and mites.
 •Antennae, wings and compound eyes are absent.
 •Body divided into head, thorax and abdomen.
 •Mouth is small and adapted for suck blood or tissue fluids of host.
 •Most of the members have poison glands or claws for paralyzing the host before sucking.
 •The first and second pair of appendages is known as chelicerae and pedipalps, respectively.
 •The first six segments of body are termed as prosoma and rest segments as opisthosoma.

Gravimetric analysis describes a set of methods in analytical chemistry for the quantitative determination of an analyte based on the mass of a solid. A simple example is the measurement of solids suspended in a water sample. A known volume of water is filtered, and the collected solids are weighed.
 
In gravimetry, the analyte needs to be first converted to a solid by precipitation with an appropriate reagent. The precipitate can then be collected by filtration, washed, dried to remove traces of moisture from the solution, and weighed. The amount of analyte in the original sample can then be calculated from the mass of the precipitate and its chemical composition.

In some cases, it is easier to remove the analyte by evaporation. The analyte might be collected—perhaps in a cryogenic trap or on some adsorbent material such as activated carbon—and measured directly. Or, the sample can be weighed before and after it is dried; the difference between the two masses gives the mass of analyte lost. This is especially useful in determining the water content of complex materials such as foodstuffs.

Behaviour have an influence on rabbit housing. Since the domestication of the rabbit is recent in terms of species evolution (200 to 300 generations at most) the behaviour of the domestic rabbit is still much like that of the wild rabbit. The reactions of wild rabbits will often provide explanations for the problems of housing domestic rabbits and suggest ways of solving them. Common behaviours observed in rabbits are:
    1.    Territorial behavior.
    2.    Social behavior.
    3.    Sexual behavior.
    4.    Maternal behavior.
    5.    Feeding behavior.
    6.    Aggressive behavior.

Synonyms : Black leg, quarter ill
This is an acute infectious but non contagious disease of cattle, goat, sheep, swine and deer  caused by Cl. chauvoei characterized by development of focal gangrenous and emphysematous myositis. This gives rise to crepitation and serosanguinous swelling in heavy muscles especially in gluteal muscles and associated with severe toxaemia and high mortality.

Soil acidity is a major constraint for crop production. The production of acid in soils is a natural process, especially in the high rainfall areas. The removal of basic cations especially Ca and Mg, by leaching and erosion results in their replacement by acidic cations, H, Al and Fe on cation exchange sites and in the soil solution, which are in dynamic equilibrium with each other. Soils, that develop from weathered granite are likely to be more acidic than those developed from shale or limestone. Organic matter decay produces H+ in soils, which also contribute to soil acidity. Intensive cropping and use of hybrid & high yielding crop varieties remove large quantities of basic elements essential for their growth i.e. Ca, Mg and K & deplete the soils. Rate of acidification is also accelerated by  faulty fertilizer (especially Nitrogen) management practices.

Plant physiology is a sub-discipline of botany concerned with the functioning, or physiology of plants. Closely related fields include plant morphology (structure of plants), plant ecology (interactions with the environment), phytochemistry (biochemistry of plants), cell biology, genetic, biophysics and molecular biology. Fundamental processes such as photosynthesis, respiration, plant nutrition, plant hormone functions, tropism, nastic movements, photoperiodism, photo-morphogenesis, circadian rhythms, environmental stress physiology, seed germination, dormancy, stomata function and transpiration, both parts of plant water relations, are studied by plant physiologists. The field of plant physiology includes the study of all the internal activities of plants those chemical and physical processes associated with life as they occur in plants. This includes study at many levels of scale of size and time. At the smallest scale are molecular interactions of photosynthesis and internal diffusion of water, minerals, and nutrients. Major sub disciplines of plant physiology include phytochemistry (the study of the biochemistry of plants) and phytopathology (the study of disease in plants). The scope of plant physiology as a discipline may be divided into several major areas of research.

Microbial contamination sources: Foods may be contaminated by microorganisms at any time during harvest, storage, processing, distribution, handling, or preparation. The primary sources of microbial contamination are soil, air, animal feed, animal hides and intestines, plant surfaces, sewage, and food processing machinery or utensils. Since most foods either carry or eventually acquire bacteria, molds, or yeasts, microorganisms are the major causes of food spoilage. The increased load of microorganisms leads to rapid spoilage.

Organisms: Bacteria and fungi (yeasts and molds) are the principal types of microorganisms that cause food spoilage and food- borne illnesses. The typical microorganisms that cause food spoilage are bacteria (e.g., Pseudomonas), yeasts (e.g., Candida), and molds (e.g., Rhizopus). The growth of microorganisms in the food will increase the load of microorganisms, and the heavier load will add to the difficulty of preventing spoilage and may influence the kind of spoilage to be anticipated.

Food spoilage may be defined as any change that renders food unfit for human consumption. These changes may be caused by various factors, including contamination by microorganisms, infestation by insects, or degradation by endogenous enzymes (those present naturally in the food). In addition, physical and chemical changes, such as the tearing of plant or animal tissues or the oxidation of certain constituents of food, may promote food spoilage. Foods obtained from plant or animal sources begin to spoil soon after harvest or slaughter. The enzymes contained in the cells of plant and animal tissues may be released as a result of any mechanical damage inflicted during postharvest handling. These enzymes begin to break down the cellular material. The chemical reactions catalyzed by the enzymes result in the degradation of food quality, such as the development of off- flavours, the deterioration of texture, and the loss of nutrients. The enzymatic changes in foods are desirable to some extent as in the case of ripening of fruits, but continued enzymatic activity beyond an optimum point becomes food deterioration due to rotting. The native enzymes may be inactivated by heat, radiation or by the use of specific chemicals.