eChapters

Weaning to 210 days: Weight in kg of feed consumed for producing one kg of live weight for the period from weaning to 210 days of age.
10 Mortality percentages (as percentage)
Pre-weaning mortality: No. of piglets died during the period birth to weaning (28/56 days) the number of piglets born alive.
Post weaning mortality: Number of piglets died during the period from 28/56th to 365 day to the total number of piglets available at weaning.
Adult mortality: Number of adult pigs died to the number started at one year (in percentage).
List of registers to be maintained:
• Birth register
• Youngstock register
• Adult stock register
• Disposal register
• Mortality register
• Weighment register
• Farrowing and growth record
• Service register
• Boar performance register
• Sow performance register
• Veterinary register
• Feed efficiency register
• Account register

Types of Breeds
Domestic cattle belong to the family Bovidae, sub-family Bovinae and can be classified into Bos Taurus and Bos indicus. They have 30 pairs of chromosomes, interbreed and are distributed throughout the tropics. The domestication of Bos taurus cattle took place some 8000to 9000 years ago and Hamitic longhorn and shorthorn types are believed to be their ancestors. The origin of Bos indicus breeds (humped cattle) were in western Asia. Both humped and hump less cattle were introduced to Africa from western Asia and into America and Australia from Europe by the immigrants. The European cattle Bos taurus were introduced in the tropics to be raised as pure-bred sand crossbred with indigenous breeds. As a result of crossing of native cattle with European dairy breeds, large numbers of crossbreeds have been produced in various tropical countries, which are being used in selection programs. Zebu Bos indicus cattle were introduced into United States in the nineteenth century for crossbreeding with European breeds. Breeds resulting from crosses are used in the southern regions of North America and tropical South America. Most of the cattle breed in the tropics evolved, through natural selection, for adaptability and survival to local environments. Often, breeds resemble each other with slight morphological differences, but because of constant inbreeding in one locality, independent breeds have evolved. In general, the cattle from drier regions are well built and those from heavy rainfall areas, coastal and hilly regions are of smaller build.
Classification of Cattle Breeds
Most indigenous cattle breeds in the tropics are multipurpose (milk, meat, draught) and that only a few breeds have good milk potential. Physical and economic parameters for some of the important indigenous dairy breeds and new crossbred types developed in the tropics are discussed. Indian cattle breeds of cattle are classified in to three types as under: a) Milch breeds: b) Dual Purpose breeds: c) Draught breeds

Definition of Animal Breeding
Animal breeding, as the application of science to the genetic improvement of animals, implies a close inter relationship between theory and its application. Genetics has provided the matrix form which logical principles could be developed and tested by experimentation and practice.
During the 20th century, genetics has assumed a broader meaning and numerous subdivisions of the discipline has emerged. Advances in animal breeding also have drawn heavily on contributions from statistics, biochemistry, physiology, economics and other disciplines. Animal breeding and reproductive physiology have been uniquely interwoven.
Animals with superior genotypes cannot contribute to succeeding generations unless their reproductive capacity is maintained at satisfactory levels.
Livestock production is an economic enterprise. Hence, animal breeding recommendations must withstand the scrutiny of economic, as well as genetic considerations, before they are accepted and integrated into enterprises by breeders. As a consequence, a close relationship between the breeder and the science, application and theory has been nurtured.
History of Animal Breeding
• Till 500 A.D. when the fall of Roman Empire began animal breeding was at its esteem. Withthe fall of Roman Empire for about 1000 years called Dark and Middle Ages, animal husbandry was at a still.
• From 1700 A.D., again there was an improvement. The beginning of modern animal breeding is to be found mainly in England and Europe.
• The British Royalty encouraged horse breeding especially for race horses. The Earls and Dukes imported bulls from Holland and bred their native stocks. Dutch cattle were introduced into Hereford shire that laid the foundation of the present Hereford cattle. By crossing the native and Dutch cattle and subsequent inbreeding, the British cattle were improved far beyond the best.

In genetic studies it is necessary to distinguish two causes of correlation is chefly pleiotropy, though linkage is a cause of transient correlation, particularly in populations derived from crosses between divergent strains. Pleiotropy is simply the property of a gene whereby it affects two or more characters, so that if the gene is segregating it causes simultaneous variation in the characters is affects. For example, genes that increase growth rate increase both stature and weight, so that they tend to cause correlation between these two characters. The degree of correlation arising from pleiotropy expresses the extent to which two characters are influenced by the same genes. But the correlation resulting from pleiotropy is the overall, or net, effect of all the segregating genes that affect both characters. Some genes may increase both characters, while others increase one and reduce the other the former tend to cause a positive correlation the latter a negative one. So pleiotropy does not necessarily cause a detectable correlation. The correlation resulting from environmental causes is the overall effect of all the environmental factors that vary; some may tend to cause a positive correlation, others a negative one.
Genetic correlation
Hazel (1943) introduced this statistic and is defined as the correlation between the additive genetic values of two traits. When two traits are considered together we have three population parameters:

There are two assumptions necessary involved in the regression of repeatability. These are:
• The variances of the different measurements are equal and have their components in the same proportions, and
• The different measurements reflect genetically the same character. If these assumptions are not valid the repeatability concept becomes vague without precise meaning in relation to the variance components.
The repeatability differs very much depending on the following:
• The nature of the trait.
• The genetic properties of the population.
• Environmental conditions under which the individuals are kept or raised.
Repeatability indicates the proportion of observed differences in performance between animals caused by differences in real producing ability. That is say, repeatability of butterfat yield is 0.40, and if a cow has an age corrected butter fat yield of 30 kilograms above the herd average, her near producing ability will be equal to 30x 0.40 = 12 kg. above the herd average. This can also be explained in a different way, i.e., if two cows differ in one lactation by 30 kg in butter fat yield. They will have difference of 12 kg of butter fat in the next lactation.
Repeatability has a value 0 to 1 and may also be expressed in percentage. Repeatability of a trait is not a constant, and measurements error or generally, varying environmental conditions tend to increase VEt and thus to decrease repeatability, shrode et al (1960) have shown the effect of a change in environmental conditions on repeatability. They obtained repeatabilities of milk yield, butter fat yield and fat percentage as 0.37, 0.32 and 0.7 respectively and after improving the management removed some of the environmental variations that had marked the cows real producing abilities.

Heritability measures the fraction of phenotype variability that can be attributed to genetic variation. This is not the same as saying that this fraction of an individual phenotype is caused by genetics. For example, it is incorrect to say that since the heritability of personality traits is about 0.6, that means that 60% of your personality is inherited from your parents and 40% comes from the environment. In addition, heritability can change without any genetic change occurring, such as when the environment starts contributing to more variation. As a case in point, consider that both genes and environment have the potential to influence intelligence. Heritability could increase if genetic variation increases, causing individuals to show more phenotypic variation, like showing different levels of intelligence. On the other hand, heritability might also increase if the environmental variation decreases, causing individuals to show less phenotypic variation, like showing more similar levels of intelligence. Heritability increases when genetics are contributing more variation or because non-genetic factors are contributing less variation; what matters is the relative contribution. Heritability is specific to a particular population in a particular environment. High heritability of a trait, consequently, does not necessarily mean that the trait is not very susceptible to environmental influences.Heritability can also change as a result of changes in the environment, migration, inbreeding, or the way in which heritability itself is measured in the population under study. The heritability of a trait should not be interpreted as a measure of the extent to which said trait is genetically determined in an individual.
The extent of dependence of phenotype on environment can also be a function of the genes involved. Matters of heritability are complicated because genes may canalize a phenotype, making its expression almost inevitable in all occurring

Individuals in a population can vary considerably on physical, cognitive, and behavioural traits. Examples include height, weight, intelligence, personality, etc. Individual differences may arise from variation in genes, environmental experiences, or a combination of both. It is generally accepted that individual differences in most traits are due to both genetic and environmental factors. To the extent that a trait is influenced by genetic (heritable) effects, phenotypic similarity is correlated with genetic relatedness.
The degree of resemblance among relatives allows for the estimation of genetic variance as well as heritability of a trait. We will now focus on how phenotypic correlation of relatives can be used to estimate the relative magnitude of genetic and environmental influences on trait variation
Partitioning of Phenotypic Values
We previously introduced the general model of Y = G +E where Y is the trait value, G is the genotypic value, and E is the environmental deviation that is assumed to have a mean of 0 so that E(Y ) = E(G). If we assume that the genetic and environmental components are independent, we have that the variance of Y is Var(Y ) = s 2 Y = s 2 G +s 2 E .
We previously focused on the decomposition of the genetic variance s 2 G into additive and dominance components, i.e., G = A+D

The amount of variation is measured and expressed as the variance. When values are expressed as deviations from the population mean the variance is simple the mean of the squared values. For example, the genotypic variance is the variance of genotypic values and the environmental variance is the variance of environmental deviations. The total variance is the phenotypic variance of the variance of phenotypic values, and is the sum of the separate components.
Components of Variance
The components of variance and the values whose variance they measure are listed as follows:
The total variance is the phenotypic variance, or the variance of phenotypic values, and is the sum of the separate components. Thus
But if genotypic values and environmental deviations are correlated, VP will be increased by twice the covariance of G with E because if P = G + E, VP = V (G + E) = VG + VE + 2 CovGE. d. The term 2 CovGE is zero when G and E are uncorrelated. Also when there is an interaction between genotypes and environments, there will be an additional component of variance due to the interaction i.e.

The concept of value, expressible in the metric units by which the character is measured. The value observed when the character is measured on an individual is the phenotypic value of that individual. All observations of means, variance, or covariances, must clearly be based on measurements of phenotypic values. In order to analyse the genetic properties of the population we have to divide the phenotypic value into two componants.
The first division of phenotypic value is into components attributable to the influence of genotypic and environment. The genotype is the particular assemblage of genes possessed by the individual, and the environment is all the non-genetic circumstances under the term ‘environment’ means that the genotype and the environment are by definition the only determinants of phenotypic value. The two components of value associated with genotypic value and the environmental deviation.
The mean environmental deviation in the population as a whole is taken to be zero. So that the mean phenotypic value is equal to the mean genotypic value. The term population mean than refers equally to phenotypic or to genotypic values. When dealing with successive generations we shall assume for simplicity that environment remains constant from generation to generation so that the population mean is constant in the absence of genetic change. If we replicate thea particular genotype in a number of individuals and measure them under environment conditions normal for the population, their mean environmental deviations would be zero and their mean phenotypic value would congiguently be equal to the genotypic value of that particular genotype.
In principle it is measurable, but in practice it is not, except when we are concerned with a single locus where the genotypes are phenotypically distinguishable or with the genotypes represented in highly inbred lines for example, considering a single locus with two alleles. A1 and A2, we call the genotypic value of one homozygote + a, that of the other homozygote – a and that of the heterozygote d (we shall adopt

Quantitative genetics is the study of continuous or quantitative traits and their underlying mechanisms. The main principals of quantitative genetics developed in the 20th century was largely in response to the rediscovery of Mendelian genetics. Mendelian genetics in 1900 centered attention on the inheritance of discrete characters, e.g., smooth vs. wrinkled peas, purple vs. white flowers. This focus was in stark contrast to the branch of genetic analysis by Sir Francis Galton in the 1870’s and 1880’s who focused on characteristics that were continuously variable and thus, not clearly separable into discrete classes. A contentious debate ensued between Mendelians and Biometricians regarding whether discrete characteristics have the same hereditary and evolutionary properties as continuously varying characteristics. I The Mendelians (led by William Bateson) believed that variation in discrete characters drove evolution through mutations with large effects I The Biometricians (led by Karl Pearson and W.F.R. Weldon) viewed evolution to be the result of natural selection acting on continuously distributed characteristics. This eventually led to a fusion of genetics and Charles Darwin’s theory of evolution by natural selection: main principals of quantitative genetics, developed independently by Ronald Fisher (1918) and Sewall Wright (1921), arguable the two most prominent evolutionary biologists.
Interestingly, Galton’s methodological approaches to continuously distributed traits marked the founding of the Biometrical school, which is what many consider to be the birth of modern statistics. Karl Pearson was inspired greatly by Galton, and he went on to develop a number of methods for the analysis of quantitative traits. We will talk more about Galton and Pearson later on in this course. One of the central goals of quantitative genetics is the quantification of the correspondence between phenotypic and genotypic values. It is well accepted that variation in quantitative traits can be attributable to many, possibly interacting, genes whose expression may be sensitive to the environment

A population, in the genetic sense, is not just a group of individuals, but a breeding group and the genetics of a population is concerned not only with the genetic constitution of the individuals but also with the transmission of the genes from one generation to the next. In the transmission the genotypes of the parents are broken-down and a newest of genotypes is constituted in the progeny, from the genes transmitted in the gametes. The genes carried by the population thus have continuity from generation to generation, but the genotypes in which they appear do not. The genetic constitution of a population, referring to the genes it carries, is described by the array of gene frequencies, that is, by specification of the alleles present at every locus and the numbers of proportions of the different alleles at each locus. If for example, A1 is an allele at the A locus, then the frequency of A1, is the proportion or percentage of all genes at this locus that are the A1 allele. The frequencies of all the allele at any one locus must add up to unity, or 100 percent.
The gene frequencies at a particular locus among a group of individuals can be determined from knowledge of the genotype frequencies. To take a hypothetical suppose there are two alleles A1 and A2, let the frequencies of genes and of genotypes be as follows:

To understand how population genetics came into being, and to appreciate its intellectual significance, a brief excursion into the history of biology is necessary. Darwin’s Origin of Species, published in 1859, propounded two main theses: firstly, that modern species were descended from common ancestors, and secondly that the process of natural selection was the major mechanism of evolutionary change. The first thesis quickly won acceptance in the scientific community, but the second did not. Many people found it difficult to accept that natural selection could play the explanatory role required of it by Darwin’s theory. This situation— accepting that evolution had happened but doubting Darwin’s account of what had caused it to happen—persisted well into the twentieth century (Bowler 1988).
Opposition to natural selection was understandable, for Darwin’s theory, though compelling, contained a major lacuna: an account of the mechanism of inheritance. For evolution by natural selection to occur, it is necessary that parents should tend to resemble their offspring; otherwise, fitness-enhancing traits will have no tendency to spread through a population. In the Origin, Darwin rested his argument on the observed fact that offspring do tend to resemble their parents—‘the strong principle of inheritance’—while admitting that he did not know why this was. Darwin did later attempt an explicit theory of inheritance, based on hypothetical entities called ‘gemmules’, but it turned out to have no basis in fact.
Darwin was troubled by not having a proper understanding of the inheritance mechanism, for it left him unable to rebut a powerful objection to his theory. For a population to evolve by natural selection, the members of the population must vary—if all organisms are identical, no selection can occur. So for selection to gradually modify a population over a long period of time, in the manner suggested by Darwin, a continual supply of variation is needed. Fleeming Jenkin argued that the available variation would be used up too fast (Jenkin 1867). His reasoning assumed a ‘blending’ theory of inheritance, i.e., that an offspring’s phenotypic traits are a ‘blend’ of those of its parents. (So, for example, if a short and a tall organism mate, the height of the offspring will be intermediate between the two.) Jenkin argued that given blending inheritance, a sexually reproducing population will become phenotypically homogenous in just a few generations, far shorter than the number of generations needed for natural selection to produce complex adaptations.

1. Introduction
Molecular techniques are laboratory methods used to study and manipulate DNA, RNA, and proteins. These techniques are crucial for analyzing and understanding the molecular basis of biological processes and have applications in various fields like medicine, agriculture, and forensics.
2. Molecular Marker Analysis
Molecular markers can be expressed as a DNA sequence or gene expression product that represents differences in genomic level in relation to a gene or a property. Molecular markers are markers that can be used to monitor differences at the DNA level and for a gene that is being investigated. DNA markers are also DNA regions in which polymorphism in individuals within a species can be determined.
Molecular markers are nontissue-specific DNA regions that are reliable, repeatable, standardizable, capable of identifying multiple regions in the genome, capable of identifying more than one region in the genome, independent of environmental conditions, dominant and codominant.
Molecular markers are classified as dominant and codominant markers. Heterozygous individuals cannot be distinguished from homozygous dominant individuals, since dominant markers are not suitable for identification of heterozygous individuals when related to dominance between alleles is dominated by dominant markers. Thus, three different individuals (AA, AA and AA) can be distinguished for any marker at any point.
The use of molecular marker systems based on this meta-analysis has become more prevalent in genetic studies conducted by the discovery of the polymerase chain reaction (PCR). The rapid development of technology and the accompanying needs, the facilities of the laboratories where the applications will occur, the biological properties of the species and the abundance of markers in the genome have contributed to the development of DNA markers [5]. Restriction fragment length polymorphism (RFLP), randomly amplified polymorphic DNA markers (RAPD), amplified fragment length polymorphism (AFLP), sequence labeled sequences (STS), microsatellites (SSR), cleaved polymorphic sequence (CAPS), single strand such as complementary polymorphism (SSCP), amplicon length polymorphism (ALP), interspecific sequence repeat polymorphism (ISSR),

The genetic blueprint contained in the nucleotide sequence can determine the phenotype of an individual. The hereditary units, which are transmitted from one generation to the next generation are called genes. A gene is a fundamental biological unit like atom which is the fundamental physical unit.
Mendel was the first scientist who proposed genes as particulate units and called them hereditary elements or factors. But the concept of gene has undergone a considerable change since Mendel’s time.
Modern Concept of Gene
A gene can be described as a polynucleotide chain, which is a segment of DNA. It is a functional unit controlling a particular trait such as eye colour. Beadle and Tatum concluded by various experiments that gene is a segment of DNA that codes for one enzyme. They proposed one gene-one enzyme hypothesis. But as some genes code for proteins that are not enzymes, the definition of gene was changed to one gene-one protein hypothesis.
Protein Hypothesis
The concept of gene has undergone further changes as the new facts came to light. Since proteins are polypeptide chains of amino acids translated by mRNA, gene was defined as one gene-one polypeptide relationship.
Some proteins have two or more different kinds of polypeptide chains, each with a different amino acid sequence. They are products of different genes. For example, hemoglobin has two kinds of chains a andß chains, which differ in amino acid sequence and length. They are encoded by different genes. Thus, gene is defined as one gene- one polypeptide relationship.

DNA is the master molecule which carries the genetic information from one generation to the other. Study of Molecular Genetics accelerated since April 25th, 1953 when James Watson and Francis Crick proposed the structure of DNA which was published in Journal called ‘Nature’. Molecular Genetics deals with the flow of genetic information and its regulation. In simple terms it can be defined as the field of biology which studies the structure and function of genes at molecular level.
Scope of Molecular Genetics
Development of techniques like nucleic acid hybridisation, cloning, sequencing etc. brought a revolutionary change in Molecular Genetics. It is of major interest to the students of biology and medicine. Though it has a lot of significance in many fields, we’ll confine ourselves to the applications of molecular genetics to the mankind. They are as follows:
i) Diagnosis of infectious diseases: Normally microorganisms are detected in the laboratory using biochemical methods. In case of molecular techniques, microorganisms are detected by using probes (short DNA or RNA sequence) which are complementary to a part of genome of the microbe. The advantage of using molecular methods is:
• Identification of pathogen is done within a short time;
• No need to cultivate the microbes;
• Latent infections can also be identified when no antibody is formed; and
• The technique can be used even when the microorganism cannot be cultured.
ii) Diagnosis of genetic diseases : Before the advent of the above techniques, counselors used to give risk estimate like one fourth risk of getting the disease, if the parents are heterozygous for an autosomal trait. But now by directly testing for the mutation, they are able to confirm the presence or absence of mutation in the fetus. It is of immense help in prenatal diagnosis.

Introduction
• Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/ cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behavior, particularly to their behaviour during mitosis and meiosis. Techniques used include karyotyping analysis of G-band chromosomes, as well as molecular cytogenetics such as fluorescent in situ hybridization (CGH). Cytogenetic approaches to studying chromosomes and their relationship to human disease have improved greatly over the past several decades.
As a mature enterprise, cytogenetics now inform genomics, disease and cancer genetics, chromosomes evolution and the relationship of nuclear structure to function. Cytogenetics involves testing samples of tissue, blood or bone marrow in a laboratory to look for changes in chromosomes including broken, missing, rearranged or extra chromosome. Cytogenetics may used to help diagnose a disease or condition, plan treatment or find out how well treatment is working.
Chromosomes
Chromosomes are the rod shaped; dark-stained bodies seen during metaphase stage of mitosis. The chromosomes are the nuclear components of special organization, individuality and function. They are capable of self-reproduction and play a vital role in heredity, mutation, variation and evolutionary development of the species. Chromosomes are thread-like structure located inside the nucleus. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure. The number of chromosomes is constant for a particular species. Therefore, these are of great importance in the determination of the phylogeny and taxonomy of the species. The number of chromosomes varies from species to species but the number remains constant in a species. But sometime, due to certain accidents or irregularities at the time of cell division, crossing over or fertilization some alteration in morphology and number of chromosomes takes place. Humans have 23 pairs of chromosomes-22 pairs of numbered chromosomes, called autosomes, and one pair of sex chromosome, X and Y. Each parent contributes one chromosome to each pair so that offspring get half of their chromosomes from mother and half from their father.

Mutation
Definition: “Mutation is the change in our DNA base pair sequence due to various environmental factors such as UV light, or mistakes during DNA replication.”
What Are Mutations?
The DNA sequence is specific to each organism. It can sometimes undergo changes in its base-pairs sequence. It is termed as a mutation. A mutation may lead to changes in proteins translated by the DNA. Usually, the cells can recognize any damage caused by mutation and repair it before it becomes permanent.
A mutation is a sudden, heritable modification in an organism’s traits. The term “mutant” refers to a person who exhibits these heritable alterations. Mutations usually produce recessive genes.

Some traits are carried on the sex chromosomes, X and Y. Most traits carried are present on only the X-chromosome. The Y-chromosome is smaller, and so, very few genes are located on this chromosome. Sex traits can be categorized into three types of inheritance:
Sex limited,
Sex-linked, and
Sex-influenced.
Sex-limited traits are traits that are visible only within one sex. For instance, barred colouring in chickens normally is visible only in the roosters. Sex-linked traits would be considered traits like sickle cell anemia and colour blindness. They are said to be linked because more males (XY) develop these traits than females (XX). This is because the females have a second X gene to counteract the recessive trait. Thus, the trait is more likely to be visible in the male.
Sex Influenced Inheritance
The condition in which the same gene acts as dominant in one sex and recessive in other sex is called as sex influenced dominance. That is, the sex influences the gene either to be dominant or recessive. The sex influenced genes are present in autosomes. This differential behaviour of the gene is due to female and male sex hormones. For example, in human being baldness is due to sex influenced gene. This trait is dominant in men and recessive in women. A man is bald in homozygous recessive as well on heterozygous condition for baldness. Whereas women exhibit baldness only in homozygous recessive condition for baldness and heterozygous condition for baldness in female sex produce normal phenotype. HN, HN -Normal female and normal male

Mendel’s 3 Laws (Segregation, Independent Assortment, Dominance).In the 1860s, an Austrian monk named Gregor Mendel introduced a new theory of inheritance based on his experimental work with pea plants.Mendel believed that heredity is the result of discrete units of inheritance, and every single unit (or gene) was independent in its actions in an individual’s genome.According to this Mendelian concept, the inheritance of a trait depended on the passingon of these units.For any given trait, an individual inherits one gene from each parent so that the individual has a pairing of two genes. We now understand the alternate forms of these units as ‘alleles’.If the two alleles that form the pair for a trait are identical, then the individual is said to be homozygous and if the two genes are different, then the individual is heterozygous for the trait.The breeding experiments of the monk in the mid-1800s laid the groundwork for the science of genetics.He studied peas plant for 7 years and published his results in 1866 which was ignored until 1900 when three separate botanists, who also were theorizing about heredity in plants, independently cited the work.In appreciation of his work he was considered as the “Father of Genetics”. A new stream of genetics was established after his name as Mendelian genetics which involves the study of heredity of both qualitative (monogenic) and quantitative (polygenic) traits and the influence of environment on their expressions.Mendelian inheritance while is a type of biological inheritance that follows the laws originally proposed by Gregor Mendel in 1865 and 1866 and re-discovered in 1900.
Mendel carried out breeding experiments in his monastery’s garden to test inheritance patterns. He selectively cross-bred common pea plants (Pisum sativum) with selected traits over several generations. After crossing two plants which differed in a single trait (tall stems vs. short stems, round peas vs. wrinkled peas, purple flowers vs. white flowers, etc), Mendel discovered that the next generation, the “F1” (first filial generation), was comprised entirely of individuals exhibiting only one of the traits. However, when this generation was interbred, its offspring, the “F2” (second filial generation), showed a 3:1 ratio- three individuals had the same trait as one parent and one individual had the other parent’s trait.

Cells divide and reproduce in two ways: mitosis and meiosis.
Mitosis is a process of cell division that results in two genetically identical daughter cells developing from a single parent cell.
Meiosis, on the other hand, is the division of a germ cell involving two fissions of the nucleus and giving rise to four gametes, or sex cells, each possessing half the number of chromosomes of the original cell.Mitosis is used by single-celled organisms to reproduce; it is also used for the organic growth of tissues, fibers, and membranes. Meiosis is found in sexual reproduction of organisms. The male and female sex cells (i.e., egg and sperm) are the end result of meiosis; they combine to create new, genetically different offspring. 

(Chroma - Colour; Some - Body)
A chromosome is a thread-like self-replicating genetic structure containing organized DNA molecule package found in the nucleus of the cell. Clear and detaile decriptions of mitotic chromosomes in plants and animals were published by Strasburger in 1875 and by the German scientist Walter Flemming in 1879- 1882.Heinrich Wilhelm Gottfried Waldeyer coined the term chromosome in 1888.
Normally Chromosomes are of two types
Autosomes - Control characters other than sex characters or carry genes for somatic characters.
Sex chromosomes (S    
Humans and most other mammals have two sex chromosomes X & Y, also called heterosome, odd chromosome, or idiosome. Females have two X chromosomes in diploid cells; males have an X and a Y chromosome. In birds the female (ZW) is hetero-gametic and male (ZZ) is homo-gametic.
Haploid: Haploid cells (N) have only one copy of each chromosome.
Diploid: Diploid cells (2N where N- chromosome number) have two homologous copies of each chromosome. The body cells of animals are diploid.In animals, gametes (sperm and eggs) are haploid.
Homologous Chromosomes
Diploid organisms have two copies of each chromosome (except the sex chromosomes). Both the copies are ordinarily identical in morphology, gene content and gene order and hence known as homologous chromosomes.Each pair of chromosomes made up of two homologs.
Homologous chromosome is inherited from separate parents; one homolog comes from the mother and the other comes from the father.

The history of genetics dates from the classical era with contributions by Hippocrates, Aristotle and Epicurus. Modern biology began with the work of the Augustinian friar Gregor Johann Mendel. His work on pea plants, published in 1866, what is now Mendelian inheritance. Some theories of heredity suggest in the centuries before and for several decades after Mendel›s work. The year 1900 marked the “rediscovery of Mendel” by Hugo de Vries, Carl Correns and Erich von Tschermak, and by 1915 the basic principles of Mendelian genetics had been applied to a wide variety of organisms—most notably the fruit fly Drosophila melanogaster. Led by Thomas Hunt Morgan and his fellow «drosophilists», geneticists developed the Mendelian model, which was widely accepted by 1925. Alongside experimental work, mathematicians developed the statistical framework of population genetics, bringing genetic explanations into the study of evolution.
With the basic patterns of genetic inheritance established, many biologists turned to investigations of the physical nature of the gene. In the 1940s and early 1950s, experiments pointed to DNA as the portion of chromosomes (and perhaps other nucleoproteins) that held genes. A focus on new model organisms such as viruses and bacteria, along with the discovery of the double helical structure of DNA in 1953, marked the transition to the era of molecular genetics.
In the following years, chemists developed techniques for sequencing both nucleic acids and proteins, while others worked out the relationship between the two forms of biological molecules: the genetic code. The regulation of gene expression became a central issue in the 1960s; by the 1970s gene expression could be controlled and manipulated through genetic engineering. In the last decades of the 20th century, many biologists focused on large-scale genetics projects, sequencing entire genomes.
Pre Mendelian Ideas on Heredity
Diagram of Charles Darwin’s pangenesis theory. Every part of the body emits tiny particles, gemmules, which migrate to the gonads and contribute to the fertilised egg and so to the next generation. The theory implied that changes to the body during an organism’s life would be inherited, as proposed in Lamarckism. Mendel’s work

The One Nation One Subscription (ONOS) scheme is a cornerstone of India’s ambition to become a self reliant and developed nation by 2047 envisaged by Hon’ble Prime Minister Shri Narendra Modi Ji. The initiative is a significant step to enhance access to scientific and academic resources across the country. This initiative can positively impact Indian journal ratings and boost subscriptions by addressing several challenges listed below:
• Increased Access to Global Resources
• Enhanced Research Quality 118 | Promoting Excellence in Agricultural Sciences
• Support for Smaller Institutions
• Boost to Indian Journals
• Fostering Interdisciplinary Collaboration
By bridging gaps in resource accessibility and improving research output, ONOS can play a pivotal role in elevating the status of Indian journals on global platforms. While evaluating Indian Journals of Agricultural and Allied Sciences, comprehensive and inclusive databases with many characteristics listed below should be adopted so as to ensure equal focus and benefit from international exposure:
• The database should have regional and multi-lingual journals with proper translation or abstracting, interdisciplinary research output, more and new journals/technical reports/official scientific documents/conference proceedings etc, open access for smaller journals to ensure readily accessible cutting-edge research in agriculture
• The database should provide more nuanced metrics that value realistic impact and localized research contributions considering immediate practical applications
• The database should include a wide range of journals across diverse disciplines, including agriculture, forestry, veterinary sciences, and environmental science with more inclusion of regional and specialized journals, providing access to a broader spectrum of agricultural research
• The database should emphasis on journals from developing regions, which often publish research addressing local agricultural challenges. This diversity helps in showcasing research contributions from regions/countries with significant agricultural economies
• The database of agriculture-related journals should overlap with other related fields viz., environmental science, biology, and social sciences, reflecting the interdisciplinary nature of agriculture. This helps researchers access a more comprehensive set of resources
• The database have detailed subject areas, allowing researchers to pinpoint agricultural science journals within relevant subfields like:

The advancement of agricultural sciences depends on systems that are fair, inclusive, and innovative. The rating of agricultural journals requires unique considerations due to the interdisciplinary and regionally diverse nature of agricultural research. By addressing structural inequities, prioritizing accessibility, and fostering leadership, the global agricultural research community can ensure its continued relevance in solving the most pressing challenges of our time (Fig. 17.1).
This book has explored the multifaceted issues facing agricultural sciences, offering a comprehensive roadmap to create systems that uphold the highest standards of equity, innovation, and collaboration.
17.1. Reforming Journal Ratings
A key pillar of advancing agricultural sciences lies in the reform of journal rating systems. Current systems often rely heavily on impact factors, a metric that, while useful, is not comprehensive. By moving toward a multidimensional evaluation framework, we can prioritize relevance, diversity of contributions, and societal impact alongside citation metrics. Reforms could include:
• Incorporating qualitative assessments of journals, such as their contributions to underrepresented research areas or regions.
• Promoting open-access journals that adhere to rigorous peer-review standards.

The final chapter of this exploration into agricultural sciences casts a forward-looking lens on the opportunities and challenges that lie ahead. As global population levels continue to rise, with estimates suggesting we will surpass 9 billion people by 2050, the demand for sustainable and efficient agricultural practices has never been more urgent. Emerging challenges, such as climate change, biodiversity loss, soil degradation, and water scarcity, coupled with rapid technological advancements, are reshaping the landscape of agricultural research and publishing (Fig. 16.1).
This chapter delves into how the integration of advanced technologies, the promotion of open-access publishing, and global cooperation can revolutionize agricultural sciences. It also highlights the importance of equity, innovation, and adequate funding in driving this transformation.
16.1. Advanced Technologies and Their Transformative Potential
In the past decade, advanced technologies like artificial intelligence (AI), machine learning (ML), and big data analytics have become central to scientific inquiry. These tools are now increasingly being applied to agricultural research, offering unprecedented opportunities for innovation. For example, AI-powered predictive models can help forecast crop yields, pest outbreaks, and weather

Policy plays a critical role in shaping the future of agricultural sciences. It determines the resources allocated to research, the inclusivity of publishing practices, and the extent of global collaboration (Fig. 15.1).
This chapter outlines actionable policy recommendations to support equitable publishing, strengthen research infrastructure, and encourage global partnerships. Furthermore, it delves into the importance of fostering interdisciplinary research and emphasizes why agricultural sciences need to continue gaining momentum in the face of global challenges.
15.1. Equitable Publishing Practices
Access to academic publishing remains a significant challenge for researchers in developing countries. High article processing charges (APCs) for open-access journals often exclude underfunded institutions and individual researchers. Policy interventions are essential to create a more equitable publishing ecosystem.
15.1.1. Subsidies for Open Access Publishing
Governments and funding agencies should subsidize APCs for researchers from low-income and middle-income countries (LMICs). For instance, the Plan S initiative-backed by organizations like the European Science Foundation—aims to make all publicly funded research open access (Plan S, 2018).

The Sustainable Development Goals (SDGs) are a set of 17 interconnected goals established by the United Nations in 2015 as part of the 2030 Agenda for Sustainable Development. These goals aim to address global challenges, including poverty, inequality, climate change, environmental degradation, peace, and justice (Fig. 14.1).
14.1. Sustainable Development Goals (SDGs)
The SDGs provide a universal framework to achieve a better and more sustainable future for all. Following is the list of the 17 SDGs
1. No Poverty: End poverty in all its forms everywhere.
2. Zero Hunger: End hunger, achieve food security, improve nutrition, and promote sustainable agriculture.
3. Good Health and Well-Being: Ensure healthy lives and promote well-being for all at all ages.

The current systems of journal rating and evaluation have long been criticized for their emphasis on narrow metrics, such as the journal impact factor (JIF), which often fail to reflect the broader contributions of academic work. Despite their widespread use, these systems frequently reinforce inequities within academia, marginalize underrepresented voices, and fail to prioritize the societal impacts of research (Fig. 13.1).
This chapter consolidates recommendations for reforming journal rating systems, emphasizing fairness, inclusivity, and societal impact. Drawing on existing literature and expert recommendations, we outline a comprehensive framework for designing a rating system that balances academic rigor with accessibility and relevance.
13.1. Revising Evaluation Metrics
The reliance on metrics such as JIF has perpetuated a cycle of prioritizing high-citation fields and well resourced institutions. Garfield (2006), the founder of the JIF, himself noted that it was never intended to serve as the singular measure of research quality, yet its dominance in academia persists. Critics argue that the JIF favors fields with inherently higher citation rates, sidelining disciplines such as the humanities, social sciences, and regional studies (Moher et al., 2018). Moreover, the JIF incentivizes salacious or sensational findings that attract citations, often at the expense of methodological rigor (Brembs et al., 2013). To address these issues, scholars have proposed alternative evaluation metrics that prioritize broader dimensions of impact. For example, the Leiden Manifesto (Hicks et al., 2015) outlines ten principles for responsible research evaluation,

National journals play a crucial role in the dissemination of regionally relevant research, particularly in specialized fields such as agricultural sciences. These journals act as accessible platforms for researchers, practitioners, and policymakers to share findings, innovations, and solutions tailored to local contexts. Strengthening national journals is essential for fostering knowledge exchange, promoting inclusivity in scientific communication, and addressing the unique challenges faced by different regions (Fig. 12.1).
This chapter explores strategies for improving the quality, visibility, and credibility of national journals, with examples from countries across the globe, including those outside North America and Europe. Case studies of successful initiatives are included to illustrate best practices for empowering local publishing platforms, with a particular focus on non-English publications.
12.1. The Importance of National Journals in Agricultural Sciences
Agricultural sciences are inherently context-dependent. Local factors such as climate, soil type, cropping systems, and socioeconomic conditions influence the challenges faced by farmers and the solutions that are most effective. National journals provide a vital medium for addressing these region-specific issues, enabling researchers to publish studies that may not align with the broader focus of international journals. Furthermore, these journals often cater to the immediate needs of local policymakers, extension workers, and educators, ensuring that research findings are translated into actionable outcomes.

Predatory journals undermine the integrity of academic publishing by charging exorbitant fees without providing rigorous peer review. These deceptive entities exploit the academic community, especially targeting early-career researchers, those from underfunded institutions, and scholars in developing countries. By prioritizing profit over quality, predatory journals erode trust in the research ecosystem, dilute scientific knowledge, and tarnish the reputation of genuine academic endeavors (Fig. 11.1).
This chapter delves into the multifaceted challenges posed by predatory journals and outlines comprehensive strategies for researchers, institutions, and policymakers to combat their pernicious effects.
11.1. Understanding Predatory Journals
Predatory journals are characterized by their lack of transparency, absence of editorial rigor, and aggressive solicitation of authors. They often masquerade as legitimate open-access journals but fail to adhere to the ethical standards of scholarly publishing. Unlike reputable journals, which uphold rigorous peer-review processes to ensure the validity and originality of research, predatory journals accept articles with minimal or no scrutiny. This results in the dissemination of low-quality or even fraudulent research, undermining the credibility of academic literature.
Several red flags can help researchers identify predatory journals. These include:

The credibility of academic publishing hinges significantly on the integrity of journal rating systems. These systems, designed to evaluate and rank academic journals based on various metrics, play a pivotal role in shaping research priorities, funding allocations, and academic career trajectories. However, despite their importance, many journal rating systems are criticized for lacking transparency and ethical rigor (Fig. 10.1).
This chapter explores these shortcomings, focusing on potential biases embedded in current systems and proposing solutions to enhance their transparency and fairness.
10.1. Role of Journal Rating Systems in Academic Publishing
Journal rating systems serve as gatekeepers in the academic publishing ecosystem. They influence where researchers choose to publish their work, how institutions evaluate scholarly output, and how funding agencies allocate resources. Metrics such as impact factor, h-index, and SCImago Journal Rank (SJR) are commonly used to rank journals. These metrics, while useful, often reduce the multifaceted nature of scholarly impact into single numerical values, potentially oversimplifying and distorting the evaluation process. The reliance on these metrics creates a feedback loop wherein highly ranked journals attract more submissions, increasing their citation counts and reinforcing their dominance. This system can marginalize smaller or niche journals that publish

Global agricultural research, an essential field in ensuring food security and sustainable development, is heavily influenced by the academic and publishing ecosystems in Europe and North America. This chapter examines the challenges faced by researchers from developing regions, focusing on limited representation in editorial boards, barriers to accessing high-impact journals, and the overarching dominance of Western institutions (Fig. 9.1).
These issues underscore the need for greater inclusivity and recognition of regional expertise to foster a more equitable global research landscape.
9.1. Dominance of Europe and North America in Agricultural Research
Publishing
The dominance of Europe and North America in agricultural research publishing is evident from the distribution of international journals in agriculture and allied disciplines. Approximately 75% of these journals originate from these regions. Breaking this down further:
• Europe accounts for 43.6% of international journals, with leading contributors including the United Kingdom (14.1%), the Netherlands (8.5%), Germany (6.2%), France (4.3%), Italy (3.5%), and other European countries (7.0%).
• North America contributes 31.4%, with the United States alone publishing 28.5% and Canada accounting for 2.9%.

In the evolving landscape of agricultural sciences, integrative research models have emerged as a cornerstone for addressing complex, multifaceted challenges. These models bridge the gap between theoretical frameworks and their practical applications, ensuring that innovations are not just conceptual but also actionable and impactful. This chapter delves into the essence of integrative research models, highlighting their significance, successful case studies, and strategies to foster their adoption and effectiveness in agricultural progress.
8.1. The Need for Integrative Research Models
Agriculture today is at the nexus of critical global challenges, including climate change, food security, biodiversity loss, and resource scarcity. Traditional, siloed research approaches often fall short in addressing these interconnected issues. Integrative research models offer a paradigm shift by combining insights from diverse disciplines such as agronomy, ecology, economics, data science, and social sciences. This approach not only enhances the depth of understanding but also ensures that solutions are holistic and sustainable (Fig. 8.1).
One of the primary drivers for adopting integrative research models is the increasing complexity of agricultural systems. Modern agriculture is no longer

Scientific leadership is a cornerstone of progress in agricultural sciences, playing a pivotal role in driving innovation, fostering collaboration, and addressing global challenges such as food security, climate change, and sustainable resource management. Effective scientific leadership ensures that research efforts are strategically aligned with pressing societal needs and that knowledge generated in laboratories and fields translates into tangible benefits for farmers, policymakers, and communities. This chapter delves into the qualities of effective leaders in agricultural sciences, the challenges they face, and strategies to nurture and support scientific leadership in this critical domain. The G20 Chief Science Advisers Roundtable (G20-CSAR), initiated under India’s G20 Presidency, is a flagship program aimed at fostering collaboration and enhancing access to scholarly scientific knowledge. This effort emphasizes the synergy of scientific expertise, ensuring that innovations and advancements are not only accessible but also utilized effectively to address pressing global concerns, such as climate change, public health, sustainable development, and digital transformation. Through this platform, India seeks to promote open science, equitable knowledge-sharing, and stronger international cooperation in research and development.
7.1. Qualities of Effective Leaders in Agricultural Sciences
To excel in agricultural sciences, leaders must embody a diverse range of qualities that enable them to inspire teams, foster innovation, and drive impactful research. These qualities include:
7.1.1. Strong Communication Skills
Effective leaders in agricultural sciences must be adept at communicating complex scientific concepts to diverse audiences. Whether engaging with fellow researchers, policymakers, farmers, or the general public, they must tailor their messages to ensure clarity and relevance. Strong communication skills are also essential for securing research funding, building partnerships, and advocating for science-based policies.

In the world of academic publishing, Article Processing Charges (APCs) have emerged as a significant barrier, particularly for researchers from countries with limited resources like India. These charges, often levied by open-access journals to cover the costs of peer review, editing, and dissemination, have created a financial divide that impedes equitable access to scholarly communication. This chapter delves into the multifaceted challenges posed by APCs and outlines potential solutions to address the inequities they perpetuate (Fig. 6.1).
6.1. The Burden of Article Processing Charges
The financial burden of APCs is disproportionately felt by researchers in developing nations. Many prestigious open-access journals charge APCs ranging from $1,000 to $5,000 or more per article. For researchers in high-income countries, these charges might be manageable, supported by robust institutional funding or grants. However, for their counterparts in countries like India, where research funding is limited and often tied to modest institutional budgets, such costs are prohibitive. The disparity in income and currency exchange rates further amplifies this challenge. A charge of $2,000, for instance, could equate to several months’ salary for a researcher in India, compared to a fraction of that amount for a researcher in the United States or Europe.

Increased importance of research publications, impact factor and citations as metrics in evaluating science and assessing the quality of research is driving unethical practices too in research and publications. Adding to that, limited access to research publications, exuberant subscription charges, heavy article processing charges and several other transboundary science and technology issues are further dividing the scientific community which is severely impacting the progress of the Nation (Pathak, 2025). The National Academy of Agricultural Sciences (NAAS) journal rating system serves as a cornerstone for researchers in India, particularly in the domain of agricultural sciences. Its significance lies in providing an accessible and systematic framework for evaluating the quality and relevance of academic journals. This chapter explores avenues for enhancing the NAAS journal rating methodologies to ensure greater accuracy, inclusivity, and ethical rigor in the assessment process. By integrating global best practices, incorporating diverse metrics, and addressing emerging challenges in the academic publishing landscape, the proposed framework aims to make NAAS ratings more robust and globally competitive. To enable universal access to scholarly scientific literature, under Aatmanirbhar Bharat it would be appropriate to strengthen our own Indian Journals to compete globally in the long run. In this regard, NAAS rating of Agri-journals has been a progressive step and NAAS should continue to upgrade its evaluation mechanism. The Professional Association of Agricultural Societies (PAAS) and NAAS partnership in upgrading of publications in Indian society journals should be encouraged.

Since its founding in the early 2000s, Scopus - which describes itself as a “source-neutral abstract and citation database curated by independent subjectmatter experts” — has been recognized as one of the top research indexes. At the time of writing this blog post, Scopus includes over 25,100 titles from 5,000 publishers, spanning 240 academic disciplines - with a staggering 76.8 million core records. Scopus encompasses research across scholarly disciplines but consists primarily of science and technology articles (Fig. 4.1).
There are many benefits to having journals added to the Scopus database. In addition to its extensive content coverage encompassing virtually all subjects, Scopus is known for its high level of academic rigor, including an annual journal re-evaluation process, which it requires as “an incentive for journals to maintain their high content quality.”
Scopus also provides a wide range of metrics for indexed content, including
• Journal-level metrics such as Citescore, which both publishes an annual impact score and gives monthly updates on how things are currently shaping up for each of the indexed titles via the CiteScore Tracker
• Article-level metrics such as PlumX, which analyzes how readers are responding to content in the broader online context (i.e., via tweets, blogs, Wikipedia references, etc.)
• Author-level metrics such as the h-index, which aims to provide an objective measure of the overall impact of individual authors’ publication histories.

Journal Citation Reports (JCR) and SCImago Journal Rank (SJR) are widely used metrics for evaluating journal impact. While JCR is based on Web of Science and emphasizes high-impact journals, SJR uses Scopus data, offering broader geographic and disciplinary coverage. This chapter evaluates their relative strengths and weaknesses, focusing on their applicability across disciplines and geographies. Multiple trends also impact research landscapes across the globe (Fig. 3.1).
Comprehensive tables provide a comparative overview of which metric is more suitable for various disciplines and global regions. The assessment of academic journals plays a critical role in research evaluation, academic promotions, and funding decisions. Two prominent journal-ranking systems, JCR and SJR, serve as benchmarks for these purposes. JCR, managed by Clarivate Analytics, primarily focuses on citation frequency over a two-year window. Conversely, SJR, developed by SCImago using Scopus data, incorporates a prestige-weighted citation approach over a three-year period (Fig. 3.2). Several of our Indian Scientific Journals are not covered by JCR. As more than 80 per cent Journals are from Europe and North America. The CLARIVATE covers only few Indian Journals most of which are published by Central Government Agencies

Journal ratings are instrumental in shaping the trajectory of scientific research, particularly in the field of agricultural sciences. They significantly influence the visibility, credibility, and funding of research endeavors, often acting as benchmarks for academic excellence and institutional prestige. However, the methodologies used to assign these ratings have been a subject of intense scrutiny due to their lack of transparency and inherent biases. This chapter explores the multifaceted role of journal ratings in agricultural sciences, shedding light on their impact on research priorities, academic careers, and international scientific collaborations. It also examines the limitations of current rating systems, including their excessive reliance on metrics like the impact factor and the geographical biases that disadvantage researchers from developing countries.
2.1. Importance of Journal Ratings in Agricultural Sciences
Agricultural sciences encompass a broad range of disciplines, from crop genetics and soil science to agricultural economics and rural development. The field is pivotal for addressing global challenges such as food security, climate change, and sustainable development. Journal ratings serve as a critical tool for researchers, institutions, and funding agencies to evaluate the quality and relevance of scientific contributions.
2.1.1. Enhancing Research Visibility
High-rated journals often serve as the primary platforms for disseminating groundbreaking research. Publishing in these journals ensures greater visibility among peers, policymakers, & practitioners. This visibility is crucial in agricultural sciences, where translating research findings into practice can have immediate and far-reaching impacts on food systems and livelihoods. For instance, research on drought-resistant crops published in a high-impact journal is more likely to influence agricultural policies and attract investment in technology transfer

Agricultural sciences stand at the forefront of human progress, addressing some of the world’s most pressing challenges - from ensuring global food security to mitigating the effects of climate change. This multidisciplinary field encompasses the study of crop production, animal husbandry, soil science, agrometeorology, biotechnology, and agricultural economics, all working collectively to improve farming systems and resource management. With the global population projected to surpass 9 billion by 2050, agricultural sciences hold the key to producing more food sustainably while minimizing the environmental footprint of agriculture. However, the effectiveness of agricultural sciences in meeting these challenges depends not only on the quality of research produced but also on the systems that govern how this research is evaluated, disseminated, and applied.
One of the most significant drivers of academic and professional success in agricultural sciences is the journal rating system. These systems serve as benchmarks for evaluating the quality and impact of scholarly publications, influencing funding decisions, academic promotions, and research collaborations. A Research Evaluation System is a structured framework or methodology used to assess and measure the quality, impact, and relevance of research activities, outputs, and outcomes. These systems are crucial in academia, industry, and research institutions to ensure that resources are used effectively and that research aligns with organizational or societal goals. The evaluation of performance in scientific research at any level - whether at the individual, institutional, research council or country level – is not easy. Traditionally, research evaluation at the individual and institutional levels has depended largely on peer opinion, but with the rapid growth of science over the last century and the availability of databases and scientometric techniques, quantitative indicators have gained importance. Yet, the methodologies underlying these rating systems are often opaque, biased, and narrowly focused on quantitative metrics such as citation counts and impact factors. Such limitations create barriers for researchers from underrepresented regions and disciplines, perpetuating global disparities in scientific research and its application. Both peer review and metrics are subject to flaws, more so in India because of the way they are used. Government agencies, funding bodies and academic and research institutions in India suffer from the impact factor and h-index syndrome. The uninformed use of indicators such as average and cumulative impact factors and the arbitrary criteria stipulated by some agencies

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.

“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.

Cellular stains are the colouring compounds used to impart different colours to varied type of cellular components and help in the demonstration of different micro-organisms such as bacteria, viral inclusions, fungal hyphae etc. The staining techniques enhance the contrast of tissue sections at microscopic level including histological, histopathological and cytological grounds. Before applying the special staining techniques on tissue sections few points which should be taken care include:
• Use of appropriate volume, concentration and type of fixative for preservation of tissue samples.
• Use of fixative with better compatibility as per the nature of tissues to be preserved.
• The tissue sections collected should not be very thick (5 mm approximately).
• Staining solutions should be immediately prepared where so ever required.
• Tissues must be sectioned with an ideal thickness between 4-6 microns.
Different types of stains routinely used to demonstrate varied type of cellular components and microorganisms:
Grocott’s Methenamine Silver (GMS) Staining Method
The fungal hyphae can be better demonstrated with Grocott’s Methenamine Silver stain (GMS). The basis for colouration of fungus is entirely based upon the oxidation of chromic acid forming aldehyde from the cell wall constituents of fungus and thereby reducing the silver-hexamine complex. The silverhexamine complex leads to the reduction of nascent Ag ions and leading the blackening of fungus in tissue sections.

Extraction of DNA from Tissue
(Using HiPurATM Multi-sample DNA Purification Kit)
Kit contents
Re-suspension buffer, Lysis solution, Prewash solution concentrate, Wash solution concentrate, Elution buffer, Proteinase K, HiElute Miniprep Spin Column (Capped), Collection tubes (uncapped), Collection tubes Dilute the prewash, wash solution and Proteinase K according to the kit.
Protocol
Prepare tissue
Weigh 25 mg of tissue, add approximately 3 ml of 0.8 per cent of normal saline. Homogenize the tissue with homogenizer or with mortar and pestle. Transfer the homogenized tissue with saline to a microcentrifuge tube. Centrifuge at 14000 rpm for 10 minutes. Discard the supernatant and use the pelleted tissue for further lysis.
Digest tissue
Add 180 μl of resuspension buffer and 20 μl of Proteinase K solution to the pelleted tissue in microcentrifuge tube. Mix by vortexing. Incubate the sample at 55oC until the tissue is completely digested (2-4 hours) in a shaking water bath. Vortex briefly after complete digestion.

Nanotechnology is manipulation of matter on an atomic, molecular, and supramolecular scale. The earliest, widespread description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology.
Nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers. This definition reflects the fact that quantum mechanical effects are important at this quantum- realm scale, and so the definition shifted from a particular technological goal to a research category inclusive of all types of research and technologies that deal with the special properties of matter which occur below the given size threshold. It is therefore common to see the plural form "nanotechnologies" as well as "nanoscale technologies" to refer to the broad range of research and applications whose common trait is size.
Introduction
A nanometer (nm) is one thousand millionth of a meter. A single human hair is about 80,000 nm wide; a red blood cell is approximately 7,000 nm wide, a DNA molecule 2 to 2.5 nm, and a water molecule almost 0.3 nm. The term ”nanotechnology” was created by Norio Taniguchi of Tokyo University in 1974 to describe the precision manufacture of materials with nanometer tolerances, but its origins date back to Richard Feynman’s 1959 talk ”There’s Plenty of Room at the Bottom” in which he proposed the direct manipulation of individual atoms as a more powerful form of synthetic chemistry. Eric Drexler of MIT expanded Taniguchi’s definition and popularised nanotechnology in his 1986 book “Engines of Creation: The Coming Era of Nanotechnology”. On a nanoscale, i.e. from around 100 nm down to the size of atoms (approximately 0.2 nm) the properties of materials can be very different from those on a

Characterization of Oct-4/Sox-2 Transcription Factors by Immunostaining for Characterization of Stem Cells
Protocol
1) The cultured cells at a density of 70,000/well in a 6 well plate or 35,000/ well in a 12 well plate are used for immunostaining.
2) The cells are washed with Dulbecco’s phosphate buffered saline (DPBS) for two times and the cells are fixed using 4% paraformaldehyde for 20 minutes at room temperature.
3) After fixation, the spent Paraformaldehyde is removed and the fixed cells are washed with 1000μl of 1x DPBS for 2 times by clockwise and anti-clockwise rotation of the plate slowly.
4) About 400μl of 3% blocking buffer was added to the wells and plate was covered with aluminum foil to prevent the exposure of light and stored at room temperature for 90 minutes.
5) After blocking, the cells are again washed once with DPBS. About 500 μl of primary antibody Oct-4 in the dilution of 1:40 is added to the well and stored at 4°C over night.
6) After overnight staining with primary antibody, the antibody solution is removed from the wells and washed with DPBS for 2 times.
7) Take 500 μl of secondary antibody anti-rabbit-FITC diluted with antibody buffer solution is added in the ratio of 1:200 and cover with aluminium foil and incubated for 90 minutes.
8) Secondary antibody is removed and washed with DPBS.

Confocal microscopy is a powerful tool that creates sharp images of a specimen that would otherwise appear blurred when viewed under a conventional microscope. This is achieved by excluding most of the light from the specimen that is not from the microscope’s focal plane.The image thus obtained has less haze and better contrast than that of a conventional microscope and represents a thin cross-section of the specimen. Laser scanning confocal microscopy has become an invaluable tool for imaging thin optical sections in living and fixed specimens ranging in thickness up to 100 micrometers. In fact the confocal microscope is often capable of revealing the presence of single molecule.
The modern confocal microscopes can be considered as completely integrated electronic systems, where the optical microscope plays a central role in a configuration that consists of one or more electronic detectors, a computer (for image display, processing, output, and storage) and several laser systems combined with wave length selection devices and a beam scanning assembly. In most advanced systems, integration between the various components is so through that the entire confocal microscope is often collectively referred to as a digital or video imaging, capable of producing electronic images.
Principle
Current instruments are highly modified from the earliest versions, but the principle of confocal imaging that was developed by Marvin Minsky is employed in all modern confocal microscopes. The image in a confocal microscope is achieved by scanning one or more focused beams of light, usually from a laser or arc-discharge source, across the specimen. This point of illumination is brought to focus in the specimen by the objective lens and laterally scanned using some form of scanning device under computer control. The sequences of points of light from the specimen are detected by a photomultiplier tube (PMT) through a pinhole (or in some cases, a slit) and the output from the

Electron-microscopy, as one of the several tools in diagnostic pathology and cell biology has contributed significantly to reveal several unimagined structures in modern era of science and technology. Several branches of biology and biomedical sciences like anatomy, pathology, physiology, biochemistry, microbiology rely on the transmission electron-microscope. This is used not only to visualize biological materials, but also to analyze the chemical makeup and physical properties of biological materials. Correlate electron microscopic and biochemical studies of cellular processes transcended the boundaries between structurally and functionally oriented sciences. The first electronmicroscope was developed by Max Knoll and Ernst Ruska in 1932 in Germany. Ruska’s efforts were appreciated by awarding him Noble Prize in Physics in 1986. The Siemens Corporation introduced the first commercial transmission electron- microscope in 1938-39 and its commercial marketing started in 1940 by different manufacturers like Hitachi (Japan), JEOL (Japan), Philips (Holland), Zeiss (Germany). Transmission electron-microscope projects electrons through a very thin section of tissue to produce a two dimensional image on a phosphorescent screen. The brightness of a particular area of the image is proportional to the number of electrons that are transmitted through the specimen. A resolution of 0.2 nm can be achieved in the transmission electron-microscope. The first electron-micrograph of biological tissue was published by Marton in 1934. Albert Claude and George Palade were awarded the Nobel Prize (1974) in the field of Medicine for their accomplishments in cell biology employing electron-microscopy

Scanning electron-microscopes are available nowadays which operate at high vacuum as well as low vacuum mode. Low vacuum mode allows viewing of wet samples, but compromise on very high resolution and high magnification images. In high vacuum mode the samples must be absolutely dry and free of any organic contaminants to avoid gas molecules interfering with both the primary electron beam and the secondary or backscattered electrons emitted from the sample. Biological specimens which are largely composed of water, necessitate additional preparatory steps to ensure that structure of the organism is retained in its natural form.
Sample preparation is essential in scanning electron microscopy. Improper sample preparations can undermine the quality of results and lead to false conclusions. SEM, unlike TEM, allows the processing of larger sized organisms and tissues. For Biological samples the smallest representative sample size should be used as the microscope’s detection capacity is as much as 1μm from the sample surface.
Samples for SEM preparations are normally collected by biopsy/ dissection/ sacrificing of an animal to remove tissues from the main body. Incisions should be done with fresh sharp blades to avoid tissue deformation from the physical forces applied with blunt blades. Collected samples should be immediately transferred to vial containing the fixative for fixation.
Microbial cultures fixation of bacteria and fungus needs to be carried out under strict safety measures. Biosafety cabinets should be used wherever possible and sample should be removed from the biosafety cabinets only after the

Lectins are sugar-binding proteins or glycoprotein of non-immune origin. In 1954 William C. Boyd alone and then together with Elizabeth Shapleigh introduced term ‘lectin’ from the Latin word lego- ‘chosen’ (from the verb legere ‘to choose’ or ‘pick out’).The earliest description of a lectin is believed to have been given by Peter Hermann Stillmark in his doctoral thesis presented in 1888 to the University of Dorpat. Stillmark isolated ricin, an extremely toxic hemagglutinin, from seeds of the castor plant (Ricinus communis).
History
Lectins, although first discovered more than 100 years ago in plants, and defined by their ability to selectively recognize specific carbohydrate structures, are ubiquitous in living organisms and throughout nature. Long before a deeper understanding of their numerous biological functions, the plant lectins, also known as phytohemagglutinins, were noted for their particularly high specificity for foreign HYPERLINK https://en.wikipedia.org/wiki/Glycoconjugate glycoconjugates (e.g. those of fungi, invertebrates, and animals) and used in biomedicine for blood cell testing and in biochemistry for fractionation.
Hundreds of lectins of plant and animal origin have been described, and the list continues to increase. The first lectin to be purified on a large scale and available on a commercial basis was concanavalin A, which is now the mostused lectin for characterization and purification of sugar-containing molecules and cellular structures. The legume lectins are probably the most well-studied lectins.