eChapters

Separation of Bacteria and Protozoa
(Method of Czerkawski, 1975)

Rumen contents are obtained just before and two hours after feeding from sheep that had been given an experimental ration. The samples of rumen contents are strained through gauze and fractioned by sedimentation and centrifugation to give preparations of mixed protozoa (PR), large bacteria (LB) and small bacteria (SB). Whole particulate matter is also isolated by centrifugation at 20000g. The detail steps are mentioned in the flow chart given below.

Wild life diseases are given more priority in the recent days due to the fact that conservation of any wild fauna canít be achieved fully, unless due efforts are equally given pertaining to the assessment of health status and the disease management, in the concerned wild animal species.

Ducks are members of the order Anseriformes and belong to the family Anatidae. Ducks, swans and geese are all members of the Anatidae family; however, ducks are smaller and have a shorter neck. Ducks are tough birds that require little care or management. People all over the world enjoyed and consume duck meat and eggs. Ducks produce more eggs than hens. The size is also larger than that of a chicken. Ducks require less attention and perform well in scavenger hunts. Ducks are second only to chickens in many countries for meat and eggs. Ducks can be raised commercially or on a small scale for meat or eggs, even in backyards with other birds or animals. 

1. How does the toxin of Clostridium botulinum affect the nervous system?

a) Blocks inhibitory transmitter substance

b) Stimulates macrophages

c) Causes haemolysis and tissue destruction

d) Induces systemic shock and death

What is the specific effect of the toxin produced by Clostridium perfringens on host cells?

a) Blocks inhibitory transmitter substance

b) Induces systemic shock

c) Causes ribosomal dysfunction

d) Disrupts plasma membranes

1 Which of the following diseases is also known as Equine Distemper?

a) Eastern Equine Encephalomyelitis

b) Western Equine Encephalomyelitis

c) Strangles

d) Glanders

The genetics is the study of inheritance and variability of organisms. Bacterial genetics is a sub-field which specifically studies transmission of genetic information from one bacterium to its progeny or between the interbreeding bacteria and the expression of genetic information.

Mutation

Hugo de Vries (1848-1935, Dutch botanist) coined the term ‘mutation’. It is originated from a Latin word which means ‘to change’. The heritable change in bacterial DNA sequences is known as bacterial mutation. The mutation will generate a new type of bacteria with altered genotypical and phenotypical characteristics, known as ‘mutant’. The parent bacterial cell from which the mutants are generated is known as ‘wild type’. In nature bacterial mutation is a rare incidence. The spontaneous mutation occurs at a rate of 1 in 10⁵ to 10⁸. The phenotypical expression of mutation occurs quickly as the bacteria are haploid with shorter generation time.

What are Genes? Genes are linear sequences of nucleotides of DNA (deoxyribonucleic acid). Each gene consists of a specific sequence of nucleotides and is responsible for determining a particular characteristic of cell. Nucleotides consist of nitrogen –containing compounds called bases, joined to the sugar, deoxyribose and to phosphate. The nucleotide bases are the purines, adenine and guanine and the pyrimidines, thymine and cytosine.

A number of genes are joined together to form a structure called a chromosome.

DNA consists of two strands of nucleotides twisted around each other into a double helical structure. The nucleotide bases are arranged in a specific sequence in each strand. The strand has a backbone of sugar and phosphate from which the bases protrude.

Etiology

The condition is usually caused by implantation of low virulent saprophytic bacteria due to traumatic injury. These organisms stimulate cell mediated immune response by persistence of antigen in the tissue.

10.1 Transformation of E. coli by electroporation Principle

Preparation of electro-competent bacteria is considerably easier than preparing cells for transformation by chemical methods. Bacteria are simply grown to mid –log phase, chilled, centrifuged, washed extensively with ice cold buffer containing 10% glycerol. DNA may be introduced immediately into the bacteria by exposing them to a short high voltage electrical discharge. Alternatively, the cell suspension may be snap frozen and stored at-70^oC for 6 months before electroporation, without loss of transforming efficiency.

Since E.coli cells are small, they require very high strengths (12.5- 15KV cm^-1) for electroporation as compared to those used to introduce DNA into eukaryotic cells. Electroporation is temperature dependent and is best carried out at 0-4°C.

The highest efficiency of transformation is obtained when the concentration of input DNA is high (1-10 μg/ml) and when the length and intensity of the electrical pulse are such that only 30-50% of the cells survive in the procedure. Under these conditions, as many as 80% of the surviving cells may be transformed. Higher frequencies of transformation (colonies/ molecules input DNA) are obtained when the DNA concentration is low (?10pg/ml).

The method outlined in this protocol is followed with most strains of E.coli and with plasmids <15kb in size. However, substantial variation in the efficiency of transformation between the strains of E. coli. has been reported. As in case with chemical transformation, linear plasmid DNAs introduced into E.coli by a pulsed electrical discharge transform very efficiently from 10 to 1000 fold but less efficiently than the corresponding closed circular DNA – perhaps because the exposed terminal of linear DNA are susceptible to attack by intracellular nucleases.

Introduction Antimicrobial resistance (AMR) has emerged as one of the gravest threats to modern medicine, undermining decades of progress in infectious disease control. It is cited by the World Health Organization (WHO) as one of the top 10 threats to global health. In 2019 alone, AMR was associated with approximately 4.95 million deaths, including 1.27 million directly attributable to resistant bacterial infections. This makes AMR a leading cause of death worldwide, surpassing HIV/AIDS (0.86 million deaths) and malaria (0.64 million deaths) in the same year. Projections suggest that if the trend continues unchecked, AMR could cause 10 million deaths annually by 2050, representing a profound human-cost escalation. Livestock and Animal burden While the quantitative burden of AMR in animals is not yet globally mapped, its effects in livestock are already both profound and alarming. Over 70% of all antimicrobials globally are used in farm animalsfrequently for growth promotion and disease prevention—not just treatment. This widespread use contributes to emerging resistance in key pathogens—Salmonella, E. coli, Campylobacter in poultry, and severe swine dysentery in pigs. In some outbreaks, swine dysentery, resistant to conventional treatment, has caused up to 90% morbidity and 30% mortality in weaned pigs. Animal-to-Human Transmission and the One Health Paradigm Antimicrobial resistance in livestock doesn’t stay on the farm—it seeps into the environment and crosses over to humans via food chains, direct contact, and environmental pathways. For example, substandard veterinary medicines and antibiotic misuse has been traced in zoonotic infections and veterinary-tohuman AMR transmission.Surveillance gaps remain: the World Organisation for Animal Health (WOAH) acknowledges that while human-related AMR mortality is well-documented, the animal health burden is not yet quantified globally—though numerous projects are underway to address this gap. The failure of conventional antibiotics to treat resistant infections highlights the urgent need for alternative therapeutic strategies. Among the most promising options is bacteriophage therapy—the use of viruses that specifically target and kill bacteria. Bacteriophages Bacteriophages, often referred to simply as phages, are viruses that infect and replicate within the bacteria. They are considered as the most abundant biological entities on Earth, with an estimated amount 10³¹ phage particles present in the biosphere—outnumbering bacteria by approximately tenfold. Phages are naturally found in diverse ecosystems including soil, ocean, sewage, and even within the microbiomes of humans and animals.

Bacteroides spp are non-spore forming gram-negative bacilli that are part of the human resident flora. Microbiologically, they are distinguished from other genera by growth in 20% bile. At present, the Bacteroides fragilis group consists of ten species: B. fragilis (the most frequent isolate), B. distasonis, B. thetaiotaomicron, B. vulgatus, B. ovatus, B. eggerrthii, B. merdae, B. stercoris, B. uniformis, and B. caccae. Since 1990, many organisms previously designated as Bacteroides have been reclassified (see chapter on Anaerobes other than Bacteroides). Bacteroides, the predominant genus in the human
intestine, are important in numerous metabolic activities and may provide some level of protection from invasive pathogens. All 10 species are usually isolated from the colon, although infections caused by or associated with them can include virtually any organ.
Characteristics
The gram-negative Bacteroides spp. or closely related genera are capsulated obligatory anaerobic bacilli that are non-spore forming, pale-staining, and some are motile by peritrichous flagella, while other taxa are non-motile. Bacteroides, Parabacteroides, Odoribacter are generally bile resistant, distinguished from genera which are bile sensitive. They are normally commensal, found in the
intestinal tract of humans (mouth, colon, urogenital tract) and other animals. Many cultures of Bacteroides strains display brown to black pigmentation on blood agar media caused by esculin hydrolysis.
Morphology
In general, all strains were stained poorly with safranin, but well with dilute carbolfuchsin. Motility was not observed in any strains. The morphology of Bacteroides fragilis in fresh cultures and in pus is not
especially characteristic. In this form, the bacillus measures 0.5 by 2.0 to 2.5 micra. Older cultures tend to develop larger forms (0.6 to 0.8 by 2.0 to 9.0 micra) but even in this state the organism cannot be distinguished from aerobic Gram-negative bacilli, by its morphology.

1. Introduction

Dairy industry size and demand precede all other segments of food industry. Reporting milk production of 146.3 million tonnes in 2014-15, India is currently occupying first position in world scenario (NDDB, 2015). In spite of limited shelf-life, milk offers various opportunities of product diversification, processing optimisation and convenient packaging solutions. All categories of dairy products are unique and vary in market value. The operating margins in value-added dairy products are almost twice of liquid milk business due to reduced need of refrigeration and added shelf-life. The appeal and satiety it offers makes them ambrosia for consumers. Baked and fried dairy products (BFDP) are those class of dairy products in which main processing operation is either baking or frying. In addition to preservation of milk solids for longer time at room temperature, manufacture of baked and fried dairy products add value to milk and also provide considerable employment opportunity (Pal and Raju, 2007;Patil, 2011). The characteristic flavour and colour development of the product rely on this unit operation or cooking method and it cannot be replaced. The unique difference in baked and fried dairy products is that in baking dough is prepared and for frying batter is prepared which vary significantly in characteristics (Table 1). The quality of the finished product greatly depends on how the dough or batter is handled.

Various types of equipment are needed and used to facilitate the process of baking. Depending upon the use, equipment may be as light equipment and heavy equipment.

Baking is no different from any other area of cooking, and as in other sectors only the best and the freshest raw material can guarantee good results. So selection of right kind of ingredients is of utmost importance. Another basic need of a professional baker and confectioner is to purchase the equipment required. The design and size depends upon the volume of sale expected. So in this chapter we are going to learn about the ingredients required for running a bakery.

1.    Major difference between unleavened and leavened bakery products is

(a) Unleavened do not form cracks on surface

(b) Unleavened do not rise significantly during baking

(c) Leavened bakery products are not attractive

(d) Unleavened products are much more stable

2.    Unleavened bakery products contain small holes throughout the finished product because of

(a) Ingredients contain fats that may swell

(b) Air incorporation between cells

(c) Incomplete coalescence of mixed ingredients

(d) High temperature baking

Nutrition plays a significant role in any livestock development program, and the expression of genetic potential for production depends on the adequate supply of nutrients. For profitable livestock production, it is essential to feed livestock nutritionally balanced diets with minimum cost and wastage, as feed cost accounts for more than half of the cost of livestock produce. Providing a balanced diet to animals can reduce feed costs, minimize nutrient wastage, and improve feed efficiency, thereby positively impacting the environment by reducing nutrient excretion.
The demand for animal products such as milk, meat, and eggs is constantly increasing to meet the needs of the growing human population. Better awareness of health and rapid urbanization, with a higher preference for quality animal products, has further fueled this demand. Human food is incomplete in terms of optimum nutrition without animal products like meat, milk, and eggs. To maximize the production of animal products according to their genetic potential, animals must be fed a balanced ration scientifically formulated to provide all essential nutrients.
Balanced feeding involves feeding livestock according to their requirements to achieve growth and production in line with their genetic potential. Understanding the nutrient requirements and the relative value of feeds as a source of these nutrients is the foundation of scientific feeding. Effective measures to achieve a balanced diet include accurate feed formulation based on the nutritional value of each feed ingredient, precise quantification, proper blending of different feedstuffs, optimal use of mineral mixtures, salt, feed additives, and the application of improved feed processing techniques tailored to the relevant species of livestock.

Industrial revolution took place in England during the period of 1760-1830. Accordingly, the production prior to demand was introduced. Many countries all over the world adopted industrial policies favouring industrial sector to achieve the fast development of the nation. Government of India also contributed its efforts in the same direction and issued the industrial policy of 1948, 1956, 1977 and so on making several financial and non financial facilities available to have substantial growth and development of industries in particular and nation in general.

Under the name of globalization and making the economy internationally competent, India took a revolutionary decision to follow new industrial policy 1991 opening the doors for investment from foreign countries and private sector even. In addition to this economic reforms have been adopted and advocated for the sake of national development. Three ‘D’ programme consisting of devaluation, decontrol and disinvestment, were also put on the national agenda, to achieve the set targets.

Pseudostem borer: Odoiporus longicollis: Curculionidae

Distribution : It is widely distributed in all banana growing areas and has got introduced into South India somewhere in the eighties and spread fast in the banana areas of Tamil Nadu, Maharashtra, Kerala and Karnataka.

Biology : Adults of the weevil are reddish brown to black and resemble the adults of the rhizome weevil in size and shape. They live for about four months. The snout is long with the characteristic geniculate antennae.