eChapters

1. TYPES AND GRADES OF IMMUNITY

The immune response, which has inherited the character of memory, as evinced by rapidity and specificity of the responses on the second exposure to antigen, was cleared the minds of scientists especially bacteriologists who could find certain cells especially lymphocytes to play a major role in immune response.
 
The fact that the blood also contains soluble protective substances both heat stable which were later known as antibody and heat labile, later called as the complement system. These two were regarded as totally separate phenomenon in the beginning years. Eventually the distinctions between specific and non-specific responses were understood.
 
There are two types of immunity
    i)    Non-specific (Innate, natural or native) immunity
    ii)    Specific (Acquired) immunity.

A. Answer the following

Q.1.    What is the difference between apoptosis and necrosis?

Ans.    In apoptosis, there is pronounced decrease in cell volume, modification of cytoskeleton, condensation of chromatin and degradation of DNA into fragments. Due to these changes, an apoptotic cell sheds tiny membrane bound apoptotic bodies containing intact organelles. Macrophages phagocytose apoptotic bodies and cells in the advanced stages of apoptosis. But there is no release of proteolytic and the lytic enzyme, cationic proteins and oxidizing molecule in the surrounding tissue and no local inflammatory response. On the other hand, in necrosis cells swell and burst releasing their contents and possibly triggering a damaging inflammatory response.

The livestock play a significant role in generating gainful employment in rural areas, particularly among the landless and marginal farmers. The Jammu region of state of Jammu and Kashmir possesses a huge livestock population which is maintained under different management systems. The region has a vast diversity in agro-climatic conditions (comprising low altitude, middle altitude and high altitude), and animal husbandry and pasture management practices. Despite having huge livestock, the production potentials are very low. There are various factors related with low production and among them parasitic diseases rank very high.

Parasitology is the branch of biological sciences that deals with the study of parasites and all the related aspects. This leads to a basic question who is a parasite ? In fact, this term is frequently used in our society for those persons who are doing nothing and depending on others for their survival. The term Parasite means the organism (parasite) which depends on other organism (host) for its nutritional requirements. By definition, it excludes the organisms which are free living and do not depend on other organism for their food requirements. There are other details in fulfilling its nutritional requirements and important one is that in doing so, it causes some harm to the host other wise it will not be a parasite but a commensal.

Corynebacteria are gram positive, non-acidfast, non-motile, non-capsulated, small pleomorphic rods. They frequently occur in rods, coccoid, club and filamentous shape. The term coryneform which refers to the pleomorphic club shape of these gram-positive bacteria. (From Coryne – meaning club). The major pathogen is Corynebacterium diptheria. Which causes diptheria in children. Corynebacteria associated with animals are called diphtheroids.

Morphology
They are gram-positive slender rod with a tendancy to clubbing at one or both ends; they are non-sporing, non-motile, non-capsulated and non-acidfast. They have granules composed of (high energy phosphate stores) – polymetaphosphate. The granules are more strongly gram positive than the rest of the bacterial cell. Stained with Loeffler’s methylene blue, the granules take up a reddish purple color and hence they are called metachromatic granules. They are called as volutinor Babes Ernst Granules. They are often situated at the poles of the bacilli and are called polar bodies. Special stains,
such as Albert’s, Neisser’s and Ponder’s have been devised for demonstrating the granules clearly. Stained smears from animal tissues often reveal groups of cells in parallel (Palisades) or cells at sharp angles to each other (Chinese letter or Cuneiform arrangement). This is due to the incomplete separation of the daughter cells after binary fission. Rhodococcus equi can appear as a gram-positive coccus or a rod or club shaped form arranged in clusters. It is capsulated and sometimes weakly acid fast.

Pasteurella and Mannheimia species are small (0.2 x 1-2 μm) non-motile, Gramnegative rods or coccobacilli. They are oxidase-positive facultative anaerobes, and most species are catalase-positive. Although non-enriched media will support their growth, these organisms grow best on media supplemented with blood or serum. They usually remain viable for only a few days on culture plates.
Some species, such as Mannheimia haemolytica, Pasteurella trehalosi and P. aerogenes can tolerate the bile salts in MacConkey agar. In smears from infected tissues stained by the Giemsa method, pasteurellae exhibit bipolar staining.
The family Pasteurellaceae comprises five genera, Actinobacillus, Haemophilus, Mannheimia, Pasteurella and Lonepinella. These genera share a number of common features and some organisms have been reclassified within these genera following deoxyribonucleic acid hybridization studies and 16s rRNA sequencing.
The pasteurellae are small (0. 2 μm by up to 2.0 μm), Gram-negative rods or coccobacilli. They are nonmotile,non-sporing, facultatively anaerobic, fermentative(except for P. anatipesrijer), oxidase-positive andcatalase - positive (except for P. caballi). Althoughunenriched media support their growth, they grow beston media supplemented with serum or blood.
Recent Changes in Nomenclature
Previous name Present name
Pasteurella ureae Actinobacillus ureae
Haemophilus avium Pasteurella avium
Pasteurella pneumotropica Pasteurella dogmatis
(Henriksen biotype)

Introduction

The epidemiological risk and hazards to global health security posed by AMR has been reiterating in several World Health Assembly (WHA) declarations and has been prioritized under the Global Health Security Agenda (GHSA). The Indian Ministry of Health & Family Welfare (MoHFW) has also identified AMR as one of the top priorities for collaborative work with WHO and the first National Action Plan on AMR has been implemented (2017-2022). India ranked fifth in antibiotic consumption in food producing animals (ruminants, pigs, and poultry) in 2010. Even though there has been a gradual reduction of 3.6% in antibiotic consumption during 2011-2019 (Koya et al., 2022), with mounting incomes and shifting in dietary patterns in favour of the consumption of animal protein, especially for poultry, the veterinary antibiotic utilization is projected to further rise by 312%, elevating India to the fourth rank by 2030 (Van Boeckel et al., 2015). FAO has already reported some of the peak resistance rates among common commensal and environmental bacteria against antibiotics like penicillin, cephalosporins, erythromycin and co-trimazoles in India (INFAAR). Resistance to the broad spectrum fluoroquinolones and third generation cephalosporin antibiotics is already more than 70% in Escherichia coli, Klebsiella pneumoniae, and, Acinetobacter baumannii and more than 50% in Pseudomonas aeruginosa. Even the microbial resistance to carbapenems, the last-resort antibiotics, is extremely high among gram-negative microorganisms (Sumanth et al., 2016). To overcome these incidences, it is impulsive to understand the microbe and drug interaction in host system.

MOST OF THE ENERGY FOR LIFE COMES FROM SUNLIGHT

Total rate of energy delivery from sun to earth (at the top of the atmosphere) = 175,000 terrawatts

Terrawatt = 10^12 watts

Rate of energy capture by plants from the sun = net primary productivity (NPP) = 100 terrawatts

Only ~ 0.06% of sunlight is captured

Captured in chemical bonds, especially in sugar

Small amounts of energy are available to specialized microorganisms from chemical reactions not linked to sunlight

It is estimated that 99% of the energy used by living cells comes from the sun

Incorporation of sunlight into chemical bonds occurs through the process of photosynthesis

“Invented” by cyanobacteria about 2 billion years ago

Phytobiotics are plant derivatives such as herbs, plant extracts or spices and have a wide range of activities such as stimulation of feed intake, growth and endogenous secretions in the gut. They act as immunomodulators resulting in decreased mortality and also have coccidiostatic, anti microbial, anthelminthic and anti-inf lammatory activities. Phytobiotics also possess hepatoprotective and hepatogenic properties, which tone up liver resulting in increased nutrient utilization and better performance. Herbs like Achyranthes aspera (Prickly Chaff Flower, Devil’s Horsewhip, Apamarga), Andrographis paniculata (Green chirayta, King of bitters, Kalamegha), Azadirachta indica (Neem), Boerhaavia diffusa (Spreading Hogweed, Punarnava), Eclipta alba (False Daisy, Bhringaraj), Ichnocarpus frutescens (Black creeper, Utpalagopa), Terminalia chebula (Black myrobalan, Haritaki). These herbs have hepatostimulant, hepato-protective, immunomodulatory and antioxidant activities (Sadekar et al., 1998; Manu and Kuttan, 2009; Michels et al., 2011, Dash et al., 2007). Further, they optimize digestion and metabolism resulting in better protein utilization, improved mucosal function and reduced cost of metabolic deamination. Andrographolide and 14-deoxy-11, 12-didehydro-andrographolide isolated from Andrographis paniculata inhibits free radical activities and lipid peroxidation. Inhibition of lipid peroxidation in meat prevents free radical production thereby preserving meat composition, colour and improvement in shelf life. In addition, it has been studied that a herb Terminalia chebula helps to reduce stress (Selvakumar et al., 2007).

Plant hormones - They are defined as:

1. Small
2. Organic compounds;
3. Synthesized by the plant;
4. Active in low concentration (<10^-6);
5. Promote or inhibit growth and developmental responses;
6. Often show a separation of the site of production and the site of action (although this isn’t as clear a distinction as in animals).

Based on these criteria, would the following substances be considered hormones? Ca²⁺, sucrose, 2 4 - D, glycine, or K⁺?

Introduction

Tissue culture refers to the technique of growing cells, tissues, or organs under controlled, artificial conditions. This allows propagation of tissues from a small sample of cells/tissues under sterile conditions. Plant tissue culture is widely used for various purposes, including the production of disease-free plants, rapid multiplication of plants with desirable traits, genetic modification, conservation of rare or endangered species, etc. Tissue culture is a valuable technique because it enables consistent and large-scale production of plants, ensures genetic uniformity, and allows manipulation of plant biology at cellular level. In this chapter, we will discuss about the major types of tissue culture techniques and their advantages, disadvantages, as well as applications in brief.

Different Types of Tissue Culture

Callus culture involves induction and growing of unorganized, undifferentiated cell masses from an explant on a nutrient/culture medium. The part of plant used to induce callus is called explant which can be tissue, organ or part of a plant.

Organ culture is used to maintain or grow an entire organ or a part of organ in vitro. It preserves the structure and function of the organ for studies or transplantation.

Embryo culture involves isolating and growing embryos from seeds or ovules in a nutrient medium. It is used to bypass seed dormancy or rescue embryos from hybrid crosses that may not develop naturally.

Cell suspension culture involves growing dispersed cells or small cell clusters in a liquid medium under continuous shaking. This is used for large-scale production of cells, secondary metabolites, and studying cell biology..

Prebiotic foods have been consumed for centuries, either as natural components of food, or as fermented food. However, interest in dietary use of prebiotics blossomed in the later 1800s and early 1900. Preliminary researches revealed that lactose had a profound effect on the pH of the caecal contents and intestine due to lactic acid fermentation resulting in enhanced calcium and phosphorous absorption. Further, it was also noted by several workers that inclusion of lactose in poultry diets resulted in better growth and reduced mortality.

A prebiotic can be defined as “a non digestible food ingredient that beneficially affects the host by selectivity stimulating the growth and/or activity of one or limited number of bacteria in the colon, and thus improves host health” (Gibson and Roberfroid, 1995). Based on this definition, Russell (1998) formulated the criteria according to which a substance can be a prebiotic. First, prebiotics are always feed ingredients that are not digested by the host, not or little used and/or metabolised as they pass through the upper portion of the intestinal tract, so they can reach the f lora of the large intestine. Secondly, they have to be able to serve as a substrate for one or more bacterial species with a potentially beneficial effect on the host. Finally they have to be able to cause a shift in the microf lora that improves the health of the host. In principle only non-digestible, fermentable feed components are prebiotics.

Precision feeding aims to supply animals with appropriate nutrients according to their changing physiological state, growth, production and environment. Conventional feeding plans are often static and may lead to waste, increased costs and environmental losses. This chapter introduces an AI-enabled framework integrating animal data, feed composition, growth characteristics and external factors. Regression, ensemble learning and other machine-learning models predict feed intake and weight gain, while linear programming and metaheuristic optimization generate efficient allocation plans. A decision-support system provides recommendations in real time. The approach can improve feed conversion, nutrient utilization, profitability and sustainability while reducing overfeeding, resource wastage and the environmental impact of livestock production.

Introduction

For agricultural applications as well as for research work, often we need to prepare solutions of different agrochemicals of varying strength, as per the requirements. Agrochemicals are used to help crop plants grow, produce, and protect them from biotic/abiotic stresses. Many of the agrochemicals (insecticides, herbicides, fungicides, rodenticides, molluscicides, nematicides, etc.) are used to protect the crop from insect pests and diseases. However, some of them (fertilizers and soil conditioners) are used to augment crop yield. While in the previous chapter (Chapter 8) we discussed about preparation of laboratory solutions, in this chapter we will briefly discuss about the preparation of different agrochemicals.

Agrochemical/agrichemical is a generalized term used for the chemicals applied in agriculture. In general, it also includes the feed-supplements used in f isheries and animal husbandry.

Agrochemicals

Fertilizers

Fertilizers are used to augment growth of crop plants and to mitigate nutrient deficiency in the soil. Fertilisers can be organic (containing natural substances, prepared through natural processes) and inorganic fertilisers (synthetic fertilizers, manufactured artificially using chemical processes using natural deposits, by chemical alterations).

Soil Conditioners

Soil conditioners include manure, livestock and leaf compost, peat that help making the soil in good condition. They are laid on the top soil and then mixed properly. They not only increase nutrient contents in the soil but also improve aeration and water holding capacity.

Microorganisms, being ubiquitous, are found in soil, air, water, food, sewage, on body surfaces as well as on degrading and decomposing substances. Their survival and continued growth mostly depend on an adequate supply of nutrients and favourable growth environments. The culture media (nutrients) consisting of chemicals support the growth of microorganisms in a given condition. They are devised in such a way that the organism should get all the nutritional requirements. These are usually prepared in laboratory by weighing and dispensing the individual ingredients. Generally, the common media contain both inorganic and organic nutrients; however, for the cultivation of large number of microorganisms, specialized media are required.

Basically the culture media are of three types: (1) Natural, (2) Semi synthetic and (3) Synthetic.

Introduction

Different types of culture media are used for culturing microbes and plant tissues. Preparing as well as sterilizing them properly following appropriate method with safety for the desired purpose are important parts of research work. In this chapter, we will discuss briefly about different types of media, their composition, preparation and sterilization in laboratory for microbial or plant tissue culture.

Culture Medium

Ingredients mixed to prepare solid, liquid or semi-solid substance to support the growth of microorganism or plant tissue in vitro (outside the body) is called culture medium. Frequently, it becomes important to grow microorganism or plant/animal tissue in vitro for any or all of the following purposes:

• To study characteristic features or properties of microorganisms.

• To identify the causal organism(s) of infection in a clinical sample, so that appropriate remedy can be determined.

• To culture/multiply microorganism or plant/animal tissues in vitro for research or commercial purposes.

• To prepare/produce biological molecules, vaccines, antigens, proteins, metabolites, etc. in vitro for research or industrial purposes.

Introduction
Ocular micrometer and stage micrometer are used to measure the size of microorganisms. The Ocular micrometer consists of a circular disk of glass which has graduations engraved on surface. A stage micrometer or objective micrometer has scribed lines on it that are exactly 0.01mm (10 micrometer) apart. Ocular micrometer is calibrated for the objective first. To calibrate the ocular micrometer for a given objective, the two scales are superimposed and determined how many of the ocular gradation coincide with one graduation on the stage micrometer scales. Thus, the distance between the graduations on the ocular micrometer can be determined and so the size of the organism can be determined.
Materials
1. Ocular micrometer
2. Stage micrometer
3. Microscope
4. Stained slides of yeast or bacteria

Introduction

Mankind has been utilizing different animal species from the dawn of civilization for a variety of purposes viz., production of milk, meat, wool, egg and leather. Apart from these, various animal species are also used for draught power, companionship, entertainment, research experimentation, sports, security etc. Livestock sector plays a crucial role in rural economy and livelihood. As per report of the working group on animal husbandry and dairying, 11th five year plan: 2007-12, the livestock sector employs eight percent of the countries labour force, including many small and marginal farmers, women and landless agricultural workers. Milk production alone involves more than 30 million small producers, each raising one or two cows or buffaloes. The organic fertilizer produced by the sector is an important input to crop production and dung from livestock is widely used as fuel in rural areas. Livestock also serves as an insurance substitute, especially for poor rural households; it can easily be sold during time of distress.