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Heart failure is the terminal outcome of heart diseases. It is defined as ventricular dysfunction (pump failure) leading to cardiac inability to maintain an adequate cardiac output. Heart failure is the outcome of filling defect, cardiac muscle abnormality, conduction defect, an excessive work load or a combination of these abnormalities.

Heart diseases in feline are silent killer as cats are able to hide their symptoms in early stage. Cats are brought to clinics only when disease is more advanced. Heart diseases are different from heart failure. Heart failure is the end stage of heart diseases.

Pathogenesis of heart failure in animals and humans is a complex phenomenon. The major abnormality in heart failure is myocardial contractility failure, disturbances in rhythm and rate of the heart, disturbances of pre load and after load, forward failure, backward failure, fluid accumulation, RAAS activation, hypoperfusion of organs, oxidative stress, activation of proinflammatory cytokines etc.

Syncope can be aptly defined as sudden transient loss of consciousness and postural tone due to an abrupt cerebral hypoperfusion leading to a decreased availability of essential nutrients like glucose. Recovery from syncope is mostly spontaneous without any medical intervention. 

Shock is a sequel to trauma or severe diseases such as heart failure, sepsis or acute inflammatory conditions like pancreatitis. Shock is generally associated with decreased supply and utilization of oxygen. The term shock is a chain of physiological events that can result in death if immediate rational treatment is not instituted.

The word cardiac arrest (CA) or heart attack is frightening. In animals heart attack does not occur in the manner as it occurs in humans. In humans the main cause of cardiac arrest or heart attack is coronary infarct. The prevalence of cardiac arrest or cardiopulmonary arrest (CPA) or heart attack in animals is relatively very low as coronary infarct is not a common disease in animals.

Diet plays an important role in the management of diseases. It is very much true in the management of dogs with heart failure also. Managing the diet of a dog with heart failure is depending on the severity and stage of heart failure and presence / absence of concurrent diseases as well deficiencies.

Anorexia in dogs with heart failure is very important clinical sign of concern as continued anorexia leads to weight loss and cardiac cachexia. Cardiac cachexia in dogs is the main reason that contributes to an owners’ decision to opt for euthanasia. It is therefore much more important to understand the various factors that lead to anorexia in dogs having heart failure. 

Oxygen therapy has been in vogue for more than century and it is key component in cardiorespiratory care both in human and veterinary medicine. It is recommended in all hypoxemic humans, dogs and cats (peripheral oxygen saturation < 90% to 94% or PaO2 < 70 mm Hg) presented with acute heart failure or respiratory diseases. But oxygen therapy in normoxemic subjects has remained controversial as some studies have shown detrimental effect (increased level of reactive oxygen species, oxidative stress, reduction in coronary blood flow and myocardial oxygen consumption) of oxygen therapy in subjects with normal oxygen level.

Heart failure in canine is being recognized with an increasing frequency throughout the world. It is the end stage pathological event progressively occurring in heart diseases. Heart failure is the condition in which heart is unable to meet the metabolic and nutritional demands of the tissues of the body due to insufficient cardiac output. Heart failure has also been observed with normal cardiac output in conditions like hyperthyroidism or anemia where tissue metabolic needs are increased.

The heart failure is an important cause of morbidity and mortality in animals and man. It is the end stage complex event of cardio-vascular diseases. For having a better understanding of heart failure in animals for adopting rational therapeutic management, it is utmost necessary to have thorough knowledge about heart, its structures, its nerve supplies, its vasculature, current generation and conduction as well as its functioning in the healthy subjects.

Annuals are the group of plants that complete their life cycle in one season or in one year during which they grow, flower and produce seed; and after this they wither out. A true annual (like zinnia) is a plant that will grow from seeds, flower, produce seeds and die in one season. Zinnias provide a succession of flowers for summer colour in any sunny location with good soil drainage.

• Harmony is the principle of landscaping.

• Texture is an important element of landscaping.

• Blue is a primary colour.

• Green in a secondary colour.

• Garden furniture is a tangible item.

Plant name         Cultivars

Amaranthus        NBRI, Lucknow: Amar Kiran, Amar Mosaic, Amar Parvarti, Amar

Tricolor                Prithu, Amar Raktabhy, Amar Suikiran, Amar Summer King, Amar

                            Summer Queen, Amar Tarang

1. Carnation is a

 a) Short day plant           b) Day neutral plant

 c) Long day plant            d) None of these

2. Lotus in Sanskrit is known as

 a) Water lily       b) Padma

 c) Kamala           d) Pankaja

Lotus

(Nelumbo nucifera)

Family: Nymphaeaceae/Nelumbonaceae

Origin: Southern Asia

Flower colour: White to deep pink

Plant part used: Flower (almost all parts)

Basic chromosome number: X=8

Somatic chromosome number: 2n =16

Scooping: It involves `Removing’ of basal plate and destroying the `Central Shoot’ of the bulb, thus encouraging the formation of bulblets round the cut edges of the scale leaves. Scooping is achieved by using a special knife or a spoon with a `Sharpened edge’ to leave a `Concave depression’ at the base of bulb. The depth of the cut is important, because the bulblets are formed on `cell tissues’ at the lowest point of the `scale leaves’.

Floriculture is the aesthetic branch of horticulture that deals with the cultivation of ornamentals, annuals, biennials and perennial plants as well as with their marketing. Flowers symbolize beauty, purity, peace and love. In India, it is a dynamic and expanding industry showing an impressive annual growth rate.

In the study of immunology, several techniques are used. These techniques are called immunotechniques. These techniques are used not only in immunology but are the methods for research and diagnostic purpose in many fields such as microbiology, biochemistry, endocrinology, hematology and in pathological laboratories.

One of the characteristics of the immune system is to recognize and discriminate self from the non-self antigens. But, sometimes, there is a failure to discriminate between self and non-self antigens in the body and an autoimmune response occurs. Body starts producing antibodies against its own cells/antigens. The self antigens against which the immune system responds are called autoantigens and the antibodies produced against self antigens are called autoantibodies.

The wellbeing of a person depends on his immune system. Any deficiency in any component of the immune system is called immunodeficiency and it may impair the normal functioning of his body and makes the person more susceptible to infections.

A tumor or neoplasm is an abnormal growth of the cells to form a lump or mass of transformed cells. This growth occurs due to loss of regulatory control of cell division. The majority of cells and organs have a balance between cell renewal and cell death. 

Transplantation refers to the implantation of a cell, tissue or organ from one site to another site in an individual or from one individual to another. It involves implanting of organs or grafting of tissues to repair defects and to stimulate regeneration.

One of the greatest achievements in science is the development of vaccines. Vaccines have been revolutionary for the prevention of infectious diseases. They have prevented a large number of deaths caused, every year, by dreadful diseases like smallpox, polio, hepatitis etc. Diseases like smallpox and polio have been successfully eradicated by vaccination.

Infectious diseases are the result of a complex interaction between the host and the microbes. Evasions of protective immunity by the parasites critically determine the survival and pathogenicity of the microbes. The invasion of the body by harmful microorganisms is called infection.

The basic purpose of the immune system is to provide defense to the body from various types of infections. But, sometimes, the system which is aimed to provide protection become damaging or even life-threatening. There are situations when immune response against harmless and inert antigens is exaggerated and cause diseases.

Cytokines are the short lived chemical messenger molecules, released by a group of cells which can modulate the functions of the same cell(by which they are produced) or other cells.

Major Histocompetibility Complex (MHC) is a closely linked cluster of genes which have codes for cell surface proteins known as MHC molecules. MHC molecules were previously called as HLA molecules. Since these molecules were first discovered on the leucocytes, these were called human leukocyte antigen or HLA molecules.

The complement system is a group of about 30 heat labile plasma proteins which constitute nearly 15% of total serum proteins. It is a system of plasma and membrane-associated serum proteins which can elicit a highly efficient and regulated inflammatory and cytolytic immune responses to different types of infectious organisms.

The interactions between antigens and antibodies are specific in nature in which an antibody recognizes an antigen through complementarities of shapes on paratope and epitope. An antigen reacts only with antibodies produced by itself or with closely related antigens. The reaction is similar to a lock and key. As a standard lock can be opened by its own key only similarly, an antibody can react only with its own antigen. Antibodies recognize molecular shapes (epitopes) on antigens.

Cell mediated immune response (CMI) is the major defense mechanism against intracellular microbes and tumor cells. It is mediated mainly by T lymphocytes. T cells originate in bone marrow but the maturation of T cells occurs in thymus.

Humoral immune response is the immune response which is mediated by antibodies.. It is called humoral immune response because antibodies are transferred with the ‘humour’ that is fluid or blood. Antibodies are the proteins produced by B lymphocytes.

Antibodies, also called immunoglobulins, are the proteins produced by the immune system against antigens. These are the protective proteins which interact with antigens and neutralize their effects. Antibodies are produced by B lymphocytes. An immunoglobulin has a Y-shaped structure consisting of four polypeptide chains.

When the body is exposed to a microbe or a foreign substance, the body makes some response which is called immune response. Immune responses are initiated by the interaction between a ligand, present on the surface of the microbe or secreted by the microbe or a foreign substance, and a receptor protein on the cell’s surface or a soluble receptor. There are several factors such as shape, charge and presence of other receptors which influence this interaction between the ligand and receptor. This ligand which is recognized by the immune system is called antigen. An antigen can be defined as an organism, a molecule, or part of a molecule which is recognized by the immune system. Often, the term immunogen is also used for antigen. Though, antigen and immunogen are used as synonyms but specifically, they are different from each other.

Innate immunity provides the first line of defense against invading pathogens. But if the pathogens are able to escape from the first line of defense mechanisms, the body uses, another set of immune mechanisms which provide defense in a more specialized manner. These are called second line of defense mechanisms. The second line of defense mechanisms are highly specific in nature. These are called adaptive immune response and provide adaptive immunity. It is also called acquired immunity since these immune responses are not present prior to the exposure of the microbes. When the body is exposed to foreign substances or microorganisms, body develops adaptive immune responses. Adaptive immunity is a set of specialized cells and processes that function to eliminate pathogens or prevent their growth.

Innate immunity or innate immune response is a set of non-specific or less specific mechanisms which provides the first and rapid line of defense. All such mechanisms exist prior to the exposure to a pathogen i.e. before the onset of the infection. It is also called inborn or innate immunity. The different components of the innate immunity like physical barriers, chemical barriers, phagocytosis, inflammation etc. act to prevent the entry or elimination of the microorganisms in a non- specific manner.

The major components of the immune system are the lymphocytes which constitute lymphoid system (Figure 2.1).The lymphoid organs are classified into two categories: primary and secondary lymphoid organs.

The study of the immune system, in its various aspects, is called immunology. Immunology is the branch of bioscience which deals with the defense mechanisms including all physical, chemical and biological properties of the organism that help it to combat its susceptibility to foreign agents and microorganisms. Immunology includes the development and functions of various components of immune system by which the body responds, destroys or neutralizes foreign agents or pathogens. It includes the study at cellular as well as molecular level. Immunology is an interdisciplinary subject which incorporates and requires the knowledge of many branches of biology like microbiology, biochemistry, molecular biology and clinical medicine.