eChapters

Introduction
The discovery of antibiotics and their subsequent use in combating infectious diseaseswas amedical breakthroughin the 20th century, as it completely changed the treatment approach to infections in general and bacterial infections in particular. In 1928, Alexander Fleming discovered Penicillin that started the started the so-called “golden age of antibiotic”. However, later in course of time the underuse, overuse and misuse of antibiotics in medical and veterinary practice led toemergence of drug-resistant pathogens resulting in phenomenon called antimicrobial resistance (AMR). In last few decades AMR has evolved silently and now threatening the human and animal health and has acquired the potential to be a next pandemic. AMR develops in a microorganism (e.g., bacteria, viruses, fungi, parasites) when it accumulates genetic changes over time and fails to respond to antibiotic(s) leading to severe illness and mortality due to infection. Although, AMR is an evolutionary event occurring naturally in microbes, but inappropriate use of antibiotics in humans and animal medicine act as key driver to its spread. Global antibiotic consumption increased between 2016 and 2023, with total consumption rising by 16.3% to 34.3 billion defined daily doses (DDDs) in reporting countries and a projected 20.9% increase when extrapolated to nonreporting countries. World Health Organization (WHO) and other authorities have called for coordinated action to address antimicrobial resistance, a threat looming large on horizon. In 2021, there were an estimated 1.14 million deaths attributed directly to Antimicrobial Resistance (AMR), with globally another 4.71 million deaths associated with AMR infections. This dataindicates a significant global health burden, with prophecy that AMR deaths could increase dangerously by 2050 if current trends continue. Global Action Plan (GAP) of the WHO highlights the importance of “One Health approach” calling for the joint action in human health, food production, animals and environmental sectors, to achieve better results. In the year 2015, the WHO initiated the Global Antimicrobial Resistance and Use Surveillance System (GLASS)to collect, analyze and share AMR data received from all countries. The Global Action Plan on AMR lists five strategic objectives to contain AMR viz., 1. optimizing the use of antimicrobials, 2. preventing infections (including the use of vaccines), 3. strengthening surveillance and research, 4. improving awareness and understanding of AMR, and 5. investing in new medical products. Vaccines stimulate the body’s immune system to recognize and attack specific pathogens and thus can prevent AMR through several ways viz., 1. reduce the incidence of infections leading to reduction in morbidity and mortality, 2. vaccines can prevent secondary bacterial infections e.g. Streptococcus pneumoniae after an initial infection with influenza, 3. produce herd immunity, 4. Prevention of infections resulting in decrease in use of antibiotics that reduces development of AMR. Immunotherapeutics can both combat and be complicated by Antimicrobial Resistance (AMR). Other immunotherapies antibodies, and immune-boosting agents can directly fight AMR by preventing infections and reducing the need for antibiotics.

Introduction
Antimicrobial resistance (AMR) constitutes a profound global health crisis, jeopardizing the efficacy of antibiotics and posing a severe threat to the foundation of modern medical practice. The rise of multidrug-resistant (MDR) pathogens, which exhibit resistance to multiple classes of antibiotics, has significantly escalated the global burden of infectious diseases, complicating treatment protocols and increasing morbidity and mortality rates. According to the World Health Organization (WHO), AMR could lead to 10 million deaths annually by 2050 if current trends continue, accompanied by economic losses projected to reach trillions of dollars due to prolonged hospitalizations, increased healthcare costs, and reduced productivity. The traditional antibiotic development pipeline has stagnated, hampered by scientific complexities, high financial costs, and stringent regulatory frameworks, resulting in a critical shortage of novel antimicrobial agents. This necessitates the exploration of innovative strategies to combat AMR and preserve the utility of existing antibiotics. Among these strategies, Crispr-Cas (Clustered Regularly Interspaced Short Palindromic Repeats and Crispr-associated proteins) systems have emerged as a groundbreaking gene-editing platform with transformative potential for addressing AMR. Initially identified as a bacterial adaptive immune mechanism, Crispr-Cas has been repurposed to enable precise targeting of genetic elements, offering novel therapeutic, diagnostic, and environmental solutions. This chapter provides a comprehensive analysis of Crispr-Cas systems in the context of AMR, exploring their molecular mechanisms, diverse applications, current limitations, and future prospects across clinical, agricultural, and environmental domains. By leveraging the precision and programmability of Crispr-Cas, researchers aim to develop targeted interventions that mitigate the spread of resistance while minimizing collateral damage to beneficial microbial communities.

The genus Bougainvillea, although having broad range of adaptability along with diverging habitate is not rich in scientific literature. The available literature on description of elemental species and mode of origin and description of different sports (cultivated species) are very poor and all the literarture are not available at one place. On the basis of available literature (Philbert 1789, Humboldt and Bonpland 1808, Fitch 1854, Bailey 1914, Merril 1923, Standley  1931, Heimerl 1934, Hottes 1947, Bor and Raizada 1948, Preston 1950, MacSelf 1951, Sargeant 1951, Van 1951, Crane and Lawrence 1952, Holttum 1955a-d, 1957a,b, Pancho and Bardenas 1959, Marigowada 1961, Sharma 1962, Menninger 1970, Ramcharan et al., 1974, Zadoo et al., 1976, Linnaeus 1789, Swarup and Singh 1995, Willdenow 1798, McDaniells 1981, Rodale et al., 1997, Gordon 2002, Lopez and Galetto, 2002, Fatima et al., 2007, Kent et al., 2007, Kobayashi et al., 2007a,b, Hammad 2009, Lack, 2004, 2012) an attempts has been made to give a short description of elemental species and important role played by Bougainvillea cv. 

Routine paraffin wax embedding technique can be conveniently discussed under the following five headings:
Stages of tissue processing
1. Fixation: Stabilizes and hardens tissue with minimal distortions of cells
2. Dehydration: Removal of water and fixative from the tissue.
3. Clearing: Removal of dehydrating solutions, making the tissue components receptive to the infiltration medium.
4. Infiltrating: Permeating the tissue with a support medium.
5. Embedding: Orienting the tissue sample in a support medium and allowing it to solidify.
Fixation-A
It is essential that tissues be fixed as soon as possible after death or removal from the body, and for this reason screw-capped specimen jars containing appropriate fixatives should be permanently kept wherever tissues for histological examination are taken regularly, for example in the operating theatre, the post- mortem room, or the animal house. The amount of fluid in the jars should be 15-20 times the bulk of the tissue to be fixed. Care should be taken to ensure early despatch of the specimens to the histology laboratory in order to avoid over-fixation in intolerant fixatives.
Tissues selected for sectioning should be sufficiently thin to be adequately fixed throughout in a reasonable time. The overall bulk of the tissue determines the volume of fixative required; the thickness will determine the speed of fixation.

Introduction
AMR is a critical global problem that affects human, environmental, and animal health. AMR is a complex problem; it is necessary to look at it from different disciplines to frame it within the One Health approach [Shrestha,2018].The World Health Organization (WHO) has identified AMR as a top ten global public health threat.Globally, there were an estimated 4.95 million deaths associated with bacterial AMR in 2019, including 1.27 million deaths attributable to bacterial AMR [O’Neill, J. (2016)]. The economic impact is equally alarming. The World Bank projects that AMR could lead to an additional US$ 1 trillion in healthcare costs by 2050, and over US$ 1 trillion in annual gross domestic product (GDP) losses by 2030.The One Health approach is defined as a joint effort of various disciplines that come together to provide solutions for human, animal, and environmental health. AMR is linked to each of these three components due to the irresponsible and excessive use of antimicrobials in various sectors (agriculture, cattle raising, and human medicine). Under the pressure of antimicrobial selection, bacteria acquire resistance genes and mobile genetic elements that can spread to other bacteria of the same or different genus. When bacteria acquire resistance to antimicrobials, they also acquire a greater ability to proliferate in animals, humans, and the natural world. Mismanagement of antimicrobials, inadequate infection control, agricultural debris, contaminants in the environment, and migration of people and animals infected with resistant bacteria facilitate the spread of resistance [Collignon,et.,al,2018]. AMR represents a global public health problem, for which epidemiological surveillance systems have been established, aiming to promote collaborations directed at the well-being of human and ani mal health and the balance of the ecosystem. Several international organizations (The World Organisation for Animal Health [OIE], WHO, and the Food and Agriculture Organization of the United Nations [FAO]) have joined forces to develop a Global Action Plan on Antimicrobial Resistance-WHO. Action taken in this plan included understanding the AMR from surveillance and research. The advisory group established guidelines for AMR surveillance to ensure all countries implement integrated surveillance, which will cover the use and consumption of antimicrobials in the human and animal population. These guide lines will provide a clear understanding of how AMR spreads in different settings and specific areas. It will allow to study the correlation between AMR and antimicrobial use in a different setting (animals, humans, and environment) and to assess the effect of interventions within and between sectors [W.H.O 2015,2017].

Introduction
Animal sector is growing very fast particularly in India as people’s purchasing power is increasing day by day. With increase in income, people’s dietary habit is shifting towards more animal origin products. The use of antibiotics for animal food production is growing very fast and India is the 4th largest country in the world regarding consumption of antibiotics in veterinary and animal husbandry sector. There is urgent need of AMR mitigation strategies to reduce the effect on human and animal health. As per the World Bank AMR can affect the global GDP upto 3.8% by 2050. Most of the countries in the world are very cautious regarding antibiotic residues and rejecting the livestock products which lead to economic loss. Many world agencies/forum such as CodexAMR Guidelines, UN Political Declaration on AMR Guidelines, Global Leaders Group on AMR reiterated judicious use of antibiotics. All-India Network Project on AMR inLivestock and Fisherieswas started in India to reduce the effect of AMR by educational awareness, adoption at field level, surveillance system and diagnosis but it didn’t meet out the desired outcome. Capacity building programmes in the field of AMR by training, reform in curriculum, collaboration from different fields of professionals can mitigate the harmful effect of AMR. According to the Food and Agriculture Organization (FAO), education and training play pivotal roles in translating knowledge into practical implementation, warranting the inclusion of Antimicrobial Use and AMR as integral components in professional education, postgraduate training, and continuing education within the food and agricultural sectors Training Strategies It involve Antimicrobial Stewardship training for healthcare professionals, public awareness campaigns, farmer education, and veterinary training on responsible antimicrobial use. Other critical elements include fostering collaboration through professional networks, building surveillance capacity, utilizing AI-driven tools for better decision-making, and promoting hygiene and infection prevention to reduce infection incidence and the need for antibiotics.
Training for Healthcare Professionals
There is substantial evidence that both healthcare workers and members of the public have knowledge gaps about appropriate use of antibiotics and mechanisms of antibiotic resistance. Surveillance is a prerequisite to estimate the magnitude of the AMR burden and to establish any intervention strategies, such as antimicrobial stewardship. In order to launch successful intervention approaches through cooperative efforts from different stakeholders (e.g., international agencies, human and veterinary medicine sectors, agriculture and animal production industries, and consumers), the existing knowledge gap needs to be addressed first.

The bougainvillea varieties reported from India have been mentioned above. The exact origin of all the varieties are not available. Breeders, sometimes, do not disclose the origin of varieties. An attempt has been made to trace out the mode of origin of different varieties as per available information (Anonymous 1981, Sindhu 2015, Sindhu and Swaroop 2015, Singh 1999, Singh et al., 1999, Nirody 1932, Sharma 1961, 1962, 1963, 1964, 1968, Sharma 1969, Pancho 1963, 1967, Marigowda 1957, Pancho and Elisco 1959, Pancho and Capinpin 1961, Pancho et al., 1961). Information available is not complete in most cases. Following abbreviations have been used – Hybrid Seedling (HS), Bud Sport (BS), Induced Mutant (IM) :

Lipids are naturally occurring fat like substances insoluble in water but are soluble in organic solvents like alcohol, ether, and chloroform etc. Some of the phospholipids are even soluble in water. All the lipids do not resemble fats.
Lipids are an important component of living cells. Together with carbohydrates and proteins, lipids are the main constituents of animal cells. Lipids include fatty acids, neutral fats, waxes and steroids (like cortisone). Compound lipids (lipids complexed with another type of chemical compound) comprise the lipoproteins, glycolipids and phospholipids.
Properties of lipids
Lipids are non-polar molecules a family of organic compounds, composed of fats and oils yield high energy and are responsible for different functions within the body. It is stored in the adipose tissue of the body. Lipids are a heterogeneous group of compounds, mainly composed of hydrocarbon chains. Lipids are energy-rich organic molecules, which provide energy for different life processes. Lipids are a class of compounds distinguished by their insolubility in water and solubility in nonpolar solvents. It is important constituent of cell membrane in biological systems, a mechanical barrier that divides a cell from the external environment.
Most of the lipids or fats are demonstrated by using fat soluble dyes. The lipid soluble dyes have greater affinity for fats, lipids, lipoproteins and triglycerides. The fat soluble dyes are:

May-Grunwald-Giemsa Stain (MGG)
Fix slide in absolute methanol
Protocol
1) Fix the slides with May-Grunwald reagent (15 drops) for three minutes.
2) Without removing the reagent, the same amount of distilled water is poured on the slide and allowed to stand for three more minutes.
3) The dilute May-Grunwald reagent is poured off and the slide is immersed for 8-12 minutes in a watch glass containing Giemsa reagent (15 drops of concentrated reagent are used for each 10 ml. distilled water). The slides should be immersed upside down in the solution to prevent the precipitate formed in the staining mixture from adhering to the preparation.
4) The slides are washed with tap water and dried in air or with filter paper. The distilled water must be neutral or otherwise buffered. With bone marrow or lymph node aspirates a longer staining time is recommended on account of the greater cell concentration. We recommend controlling the staining time with the microscope.

Introduction

In the last decade, digitalization has transformed every aspect of life and society, changing almost every area of our day-to day lives. Not just that; the rate of change that is happening is astonishing and only going to accelerate further. From the way, we work and communicate to how we organize our lives, digital tools and technologies are everywhere including the veterinary sector. Veterinarians are recognizing the need to depart “the analog island” and increasingly willing to embrace digital solutions. Undoubtedly, digitalization is crucial when it comes to boosting efficiency and quality in veterinary medicine and delivery of animal healthcare to masses across various geographies and resource poor setups. Uniquely these digital tools helps vets also to focus on the needs of patients and animal owners.

Stains are inevitable in histology to impart variable colours to different tissue components. In this domain, hematoxylin (H) and eosin (E) dyes are the dominant stains. According to an estimate nearly 2.5 million slides are stained with H & E each day, reflecting its enormous use in histology laboratories. Hematoxylin is a natural dye, extracted from bark of logwood (Haematoxylon campechianum), whereas eosin is a synthetic dye. The journey of using natural dyes in histology began with A. Leeuwenhoek (1673) who used “saffron”, an extract of saffron crocus. It continued until the systematic studies of C Weigert, J Gerlach, P Ehrlich and H Gierke to the second half of the 19th century and then this filed became subdued by the emerging era of synthetic dyes for their effective tinct. Today most of the stains used in histology are the synthetic dyes. Often, these dyes need further treatment with chemicals to formulate the final working solutions. Synthetic dyes are efficient, but may pose serious health hazards. The awareness on such hazards even has gone to an extent of withdrawal of some of the dyes from histological techniques. Frequent exposure to these chemicals constantly affects the health of the laboratory technicians, pathologist and mainly those working in the laboratory.
Therefore, an era has triggered on the current day, to seek for use of the natural herbal dyes in histology. Despite various shortcomings with use of natural herbal stains, they can still be sought as an analogous to the conventional stains. The concern for safety, cost-effective, eco-friendly, biodegradability and local availability is driving the quest to explore the abundant local plant resources for this purpose. The precise research on various parts of the plants such as stems, leaves, flowers, fruits, roots and seeds used for dye extraction in our laboratory to stain the cell cytoplasm replacing the conventional eosin stain are chronicled in this documentation.

4.1. Classification

The class Aves, also known as birds, is a group of warm-blooded vertebrates characterized by feathers, toothless beaked jaws, laying hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds are found worldwide and come in a variety of sizes, from the tiny humming bird to the massive ostrich.

The classification of Aves can be broken down into two major subgroups: Palaeognathae and Neognathae.

4.1.1. Palaeognathae: Also known as ratites, these are flightless birds with f lat sterna (breastbones) that lack keels, which are important for flight muscle attachment. Examples of palaeognathae include ostriches, emus, rheas, and kiwis.

“A Message of Wisdom from Dead to Living”
Postmortem examination is systematic exposure and scientific examination of tissue and organs of an animal carcass or cadaver or dead body to determine the nature, extent and cause of death. It is an important diagnostic procedure which supports the diagnosis of a disease in an animal flock or herd. Several times the clinical diagnosis alone may not be sufficient to determine the process of disease occurrence. In such cases gross and histopathological investigations may give a valuable outlook to understand the mechanism of the disease process.
Role of necropsy examination
1) Critical necropsy examination complements the clinical medicine by providing a sure short supplement to the clinicians and students.
2) Necropsy examination pave a path for rational diagnosis of cause of death.
3) Necropsy examination helps to assess the line of treatment and diagnostic protocols followed during the illness.
4) Systemic necropsy examination helps to understand the pathogenesis of disease condition in a better manner.
5) Necropsy examination of animals died in a particular region helps to prevent the life of several animals in future.
6) Thorough necropsy examination in animals is an important tool to provide an expert advice to issue Insurance Certificate.
7) Post-mortem examination is often helpful to investigate the death of the animals counted under vetro-legal or forensic aspects.

The constitution of different solutions plays a significant role in successful demonstration of anatomical techniques especially the special stains. The sincerety begins at the time of fixation of the tissues and deviation at any step may lead to failure of procedure. The chemical reagents required for a particular method have been enlisted at their sites however; the commonly used chemicals are comprehended at one place for convenience of the users.

Introduction

Canine atopic dermatitis (CAD) is a chronic inflammatory skin disease marked by itching (pruritus), redness (erythema), and recurrent infections. While traditionally considered an immune-mediated condition, recent studies highlight the significant role of skin barrier dysfunction in its development. A key aspect of CAD is the compromised skin barrier, which increases permeability to allergens, irritants, and microorganisms, thereby worsening the disease. The skin barrier is a complex, dynamic structure essential for protecting dogs from environmental challenges. The stratum corneum—the outermost layer of the epidermis—serves as a crucial defense against environmental insults, allergens, and pathogens. In dogs with atopic dermatitis, this barrier often becomes impaired, leading to increased transepidermal water loss (TEWL), greater allergen penetration, and secondary infections. This dysfunction both results from and contributes to the condition, creating a self-perpetuating cycle of barrier disruption, inflammation, and immune dysregulation.

Introduction

Mithun (Bos frontalis), or ‘Gayal’ or ‘Eso’ or ‘Sial’ or ‘Sandong’ or ‘Wei’, is a rare bovine species, exclusively found in the northeastern hill region (NEHR) of India at an altitude of 300-3000 m. It plays an important role in the socio-economic and cultural life of indigenous tribes of Arunachal Pradesh, Nagaland, Mizoram and Manipur and is aptly referred to as the ‘Pride of Northeast India’ (Mukherjee et al. 2019). Besides India, mithun population is distributed to China, Bangladesh, Thailand, Bhutan, Myanmar, and Malaysia. The Indian mithun is a medium- to large-sized majestic ruminant with a characteristic jet-black body, an ash-colored forehead, and ‘white stockings’ on all the limbs. This unique animal has a special preference for salt feeding, is a skilled browser even in steep, hilly terrain, and does not need pasture land like cattle. Mithun is primarily reared under a free range system as an important source of lean meat, rich in amino acids, proteins, PUFA, etc. On September 1, 2023, the Food Safety and Standards Authority of India (FSSAI) officially certified the mithun as a food animal (Joshi et al., 2021; Lalchamliani et al., 2024; Ramesh et al., 2024). Compared to milk from other species, mithun milk has much larger quantities of fat, lactose, solids-not fat (SNF), calcium, important vitamins A, D, and E, essential amino acids, and polyunsaturated fatty acids (Devi et al., 2023).

Introduction

Avian medicine is a rapidly growing field, with an increasing number of exotic bird species being kept as pets. However, the unique anatomy, physiology, and behaviour of these birds present several challenges as well as new opportunities for veterinarians and researchers.Now a day’s birds are gaining popularity over dogs and cats because of various reasons listed below:

a. They are more suited in present life style as can be suited well in small spaces.

b. They require low maintenance with relative low cost of maintenance and live longer life.

c. They form very strong bonds with their owners.

Birds can be classified into different families, such as Psittaciformes, Passeriformes, Columbiformes, Piciformes, Anseriformes, Galliformes etc. containing numerous species (>10,000). The first documentation of parrot as a pet was found in Rig Veda, written more than 3000 years ago. Evidence of bird keeping is observed in ancient civilizations of Greece, Rome, China and Egypt. In Greek mythology, Raven (a crow) was mentioned as a symbol of good luck and was associated with God Apollo (God of prophecy). Crows are also considered as ancestors in Hindu mythology and food (pinda) is offered to crows during ritual of paying homage to dead persons. In most of the countries psittacine and passerine birds are preferred as pet birds.

Introduction

Endocrinology is the study of the endocrine system, which includes the glands and their secretions known as hormones. Hormones are essential for animal behaviour, growth and development, metabolism, lactation, reproduction, excretion, and reabsorption of inorganic ions. Therefore, if a certain hormone concentration in blood or another body fluid is detected, it provides the pathophysiology of the representative endocrine gland.

Endocrine glands, the cells or tissues they govern, and the secretory substances (hormones) they produce are investigated using a number of methodologies. They are as follows:

1. Surgical methods (e.g., hypophysectomy, gonadectomy, etc).
2. Chemical ablation or impairment (e.g., alloxan or streptozotocin agents that selectively destroy the insulin-secreting beta-cell, etc).
3. Hormone replacement therapy (e.g., estrogen during menopause to reduce the risk of bone fracture related to osteoporosis, etc).
4. Immunological neutralization of hormone activity (e.g., contraception both male and female, injection of antibodies against NGF resulting in failure of sympathetic nervous system development, etc).
5. Tissue extraction and purification (e.g., progestin is a synthetic hormone that mimics progesterone, etc.).
6. Histological-cytological studies (e.g., employment of a battery of histological stains to characterize each pituitary cell, etc).
7. Bioassays (e.g., oxytocin-induced contraction of rat uterine myometrial tissue strips, etc).

By 2050, the global population is projected to reach approximately 9.8 billion, requiring a 70% increase in food production to meet the growing dietary demands. The livestock sector will play a crucial role in addressing this rising need through sustainable animal production, contributing to food security, poverty alleviation, public health, and food safety. To tackle the challenges posed by population growth and to achieve the United Nations Sustainable Development Goals (SDGs), technological advancements and innovations will be essential in transforming the food and agriculture sectors.

In light of these challenges, Veterinary Services are more critical than ever. They are essential for enhancing livestock health and productivity, ensuring high-quality food that meets safety standards, and mitigating risks associated with animal diseases and public health. Additionally, Veterinary Services must contribute to global efforts in addressing issues such as food security, antimicrobial resistance, climate change, and the depletion of natural resources.

Introduction

Growth is the irreversible gain in body weight, size, length, and circumference. It is accomplished by two fundamental processes: hypertrophy (increase in tissue, cell volume and progressive accumulation of intercellular substances) and hyperplasia (growth as a result of cellular multiplication by mitotic division). Animal growth is influenced by both genetic and environmental factors.

Animal body growth and weight gain play a critical role in reproductive performance. It also acts as one of the traits to evaluate the breeding value, optimize management & feeding practices, and prepare the correct dose of therapeutic pharmaceuticals to treat animal diseases. As a result, measurement of body growth is essential for the selection of superior germplasm, feeding & housing management, health care management, and optimizing other environmental conditions that have an impact on animal growth for an economically viable animal industry.