ICAR ANIMAL SCIENCE SHORT NOTES.pdf

1 | C o m p i l e d b y D r A m e e r S u h a i l
ICAR ANIMAL SCIENCE
SHORT NOTES Part 1
BEFORE U GO
 Refer this notes only to brush up your knowledge
 If you really wish to get good marks refer ur notebooks first which
can be completed in a month. I vote for Tanuvas notes and it is
easily available.
 This notes contain many spelling and grammar mistakes as it was
created to brush up my knowledge
 Eventhough this note was created after referring textbooks , this
does not contain the whole portion of the subjects
 This note was written I in my on way and that may not be
understandable to u
 Some topics are neglected in this (such as physiology and lpm) as I
was confident in those .
 Part 2 of animal science short notes and veterinary science stream
will be uploaded soon
 Attend online practice exams
 Do mail @ ameersuhail07@gmail.com in case of any doubts
AGB
Unit of heredity ….gene
Genetics is the scientific study of heredity and variation

Geno means to give birth by William bateson
Gene phenotype and genotype by William johansen
Father of genetics gregor johann mendel
Antonie van Leeuwenhoek was one of the first to observe spermatozoa
Nicolas Hartsoeker produced an image of tiny men inside the sperm,
which he called " animalcule" or "homunculus
Binomial nomenclature Carl Linnaeus
acquired characters are inheritable, an idea also known as
Lamarckism….its called soft inheritance
modern evolutionary theory…charles Darwin….natural selection…
Regnier De Graaf is famous for having discovered the ovarian follicle
(which is named Graafian follicle in his honour).
The establishment of cell theory is generally attributed to Matthias Jacob
Schleide and Theodor Schwann
Cell nucleus Robert brown
Friedrich Leopold August Weismann proposed the theory of the
continuity of the germplasm and predicted the reduction division of the
chromosomes during the formation of the germ cells. He proposed the
germ plasm theory, according to which (in a multicellular organism)
inheritance only takes place by means of the germ cells -the gametes
such as egg cells and sperm cells.
Walter Flemming used the term chromatin for the nuclear substance and
coined the term mitosis.
Heinrich W.G. Waldeyer introduced the term chromosome
Wilhelm L. Johannsen introduced the term gene to replace older terms
like factor, trait, and character. He coined the terms phenotype and
genotype

established the chromosome theory of heredity and also discovers the
first sex-linked lethal gene ………….thomas hunt morgan …with
drosophila…
George Wells Beadle and Edward Lawrie Tatum proposes the one gene -
one enzyme (polypeptide) concept
Oswald Theodore avery DNA
Francis Crick, James D. Watson and Maurice Wilkins ……….molecular
structure of nucleic acid
Har Gobind Khorana and Nirenberg …..GeneticCode
Human Genome project….13 year old…1988
Compound microscope…zakarias jansen
Cell contents are called the protoplasm.
Genes reside in cell nucleus.
Robert hooke…cell….cell structure….malpigi….
Animal cell don’t have cell wall…hence diversified….organells are special
sub units with specific function and enclosed with its own
membrane.cells are bound using collagen…but pectin in fungal and
plants….anima cell have small varoule…
The cell membrane (also called the plasma membrane, plasmalemma,
or "phospholipid bilayer") is a double layer of phospholipids.
…..selectively permeable…
Cytoplasm….collective term for the cytosol(internal fluid) plus the
organelles and inclusions suspended within the cytosol
Centrioles…..they are arranges in perpendicular fashion to form
centrososme…plant centrosome don’t have centrioles…centrosome are
microtubule organising centers…MTOC…
During division of cells centrosome is also duplicated…The two
centrosomes move to opposite sides of the nucleus of the dividing cell
and from each centrosome, microtubules grow into a "spindle" which is

responsible for separating replicated chromosomes into two daughter
cells. Thus each daughter cell inherits one centrosome.
Centriole is made up of ring of nine bundles of microtubules and each
bundle is composed of three microtubules
The Golgi body or dictyosome processes and packages the
macromolecules such as proteins and carbohydrates synthesized by the
cell into membrane - bound vesicles for cell secretion (exocytosis) or for
use within the cell …they contain membrane bound stacks called
cisternae..the secretory vesicles secrete neurotransmitters,hormones etc
after binding to cell membrane through porosome….and go out by
exocytosis.
The ER is a continuation of the outer nuclear membrane and provides a
pipeline between the nucleus and the cytoplasm. The space within the
ER is called the ER lumen which acts as a transport system for the cell.
SER involved in the synthesis of lipids and membrane proteins. The
function of the rough endoplasmic reticulum is to synthesize and export
proteins and glycoproteins.
Ribosomes are packets of RNA and protein that are sites for the
assembly of proteins in a process called Translation. Ribosomes are
classified as being either "free" (anywhere in the cytoplasm) or
"membrane-bound" (endoplasmic reticulum).
Mitochondria…cellular power plant,,,,,,double membraneos….inner
membrane is bounded and has projections called cristae…..inner
membrane space is called matrix…
Lysosome …cell vesicles” or "suicide-bags" or "suicide - sacs". contain
digestive enzymes necessary for intracellular digestion….. rare in plant
cells. …..digest excess or worn-out organelles, food particles, and
engulfed viruses or bacteria,
Peroxisomes contain oxidative enzyes break down organic molecules by
the process of oxidation to produce hydrogen peroxide,hence the name
and then quickly into water and oxygen. They break down fatty acids..
Vacuoles …digested plus waste materials…
Cytoskeleton is a network of protein filaments,such as microtubules and
microfilaments and motor proteins in the cytoplasm that give shape to a
cell, hold and move organelles, and typically involved in cell movement

Nucleus…coordinates cell activity such as division,synthesis etc…largest
organelle containing nucleolus….double membrane…also contains a
number of other non-membrane delineated bodies like Cajal bodies,
Gemini of coiled bodies, polymorphic interphase karyosomal association
(PIKA), promyelocytic leukaemia (PML) bodies, paraspeckles and
splicing speckles …liquid is called nucleoplasmmm….Nucleus contains
most of the cell's genetic material, double helix DNA molecules held in
complex with a large variety of proteins, such as histones, to form
chromosomes. ..
Nuclear envelope or membrane also known as the perinuclear envelope,
nucleolemma or karyotheca. The outer membrane is continuous with
the rough endoplasmic reticulum.
The space between the two membranes that make up the nuclear
envelope is called the perinuclear space (also called the perinuclear
cisterna). Nuclear Pores are formed at sites where the inner and outer
membranes of the nuclear envelope are joined.
The nucleolus is a membrane less organelle found in the nucleus, and is
sometimes called a sub organelle.all cells don’t have nucleolus.
Chromosome (chroma - colour; some - body) …
Heinrich Wilhelm Gottfried Waldeyer coined the term
Autosomes control somatic characters…..sex chromosomes or
gonosomes insex determinatiom…two sex chromosomes or heterosome,
odd chromosome, or idiosome.
Female Birds are heterogametic..
Haploid cells (N) have only one copy of each chromosome. Eg
egg,sperm…
Cat Felis catus 38
Cattle Bos taurus, Bos
indicus
60
Dog Canis familiaris 78
Donkey Equus asinus 62
Goat Capra hircus 60
Horse Equus caballus 64
Human Homo sapiens 46
Pig Sus scrofa 38
Rabbit Oryctolagus
cuniculus
44
River buffalo Bubalus bubalis
(riverine type)
50
Swamp buffalo Bubalus bubalis
(swamp type)
48
Sheep Ovis aries 54

Llama Lama glama 74
Mule (Hinny, hybrids of
horse and ass)
63
African buffalo or
Cape buffalo
Syncerus caffer 52
Bison Bison bison 60
Chimpanzee
Pan troglodytes 48
Elephant Elephas maximus
(Asian) and Loxodonta
Africana (African)
56
Golden hamster Mesocricetus auratus 44
Gorilla Gorilla gorilla 48
Guinea pig Cavia cobaya 64
Hare Lepus nigricollis 48
Chicken
Gallusdomesticus
78
Domestic duck Anas
platyrhyncha
80
Emu Dromaius
novaehollandiae
80
Goose Anser anser 80
Guinea fowl Numida
meleagris
74
Japanese quail Coturnix
japonica
78
Muscovy duck Cairina
moschata
80
Ostrich Struthio camelus 80
Pigeon Columbia livia 80
Ring-necked
pheasant
Phasianus
colchicus
82
Turkey Meleagris
gallopavo
80
Drosophila 8….Pea plant….14
The DNA of eukaryotic cells is tightly bound to small basic proteins
(histones) that package the DNA in an orderly way in the cell nucleus.

chromatin, which typically contains about twice as much protein as
DNA.
- H1, H2A, H2B, H3,
and H4 which are very similar among different species of eukaryotes.
Centromere or kinetochore is primary constriction….p or petite or small
arm…q arm is long….
The sequences at the ends of eukaryotic chromosomes, called telomeres
A small chromosomal segment separated from the main body of the
chromosome by a secondary constriction is called Satellite
Chromosome thinnest plus longest in interphase or resting
phase….thickest and shortest in metaphase..
Central centromere metacentric….during anaphase its v shaped…..away
from middle….is submetacentric and j or L shaped in anaphase….toward
tip acrocentric…at tip telocentric…in both cases rod shaped,,,,,,
Other types based on numb of centromere…monocentric,
acentric,dicentric,polycentric
Morphology of somatic chromosomal complement of an individual is
called karyotype…
Avian karyotype is different from mammalian karyotype because of
presence of very small autosomes called microchromosomes.its
diagrammatic representation is called ideogram..
repeated rounds of DNA replication without any cell division (called
endoreplication
Polytene chromosomes or salivary gland chromosomes are giant
chromosomes happens due to endopelication common to many dipteran
(two-winged) flies salivary gland. Discovered by EG Balbiani… its
centromere is called chromacenter…mainly in larvae to promote growth..
Lampbrush chromosomes….
It consists of an axis from which paired loops extend in opposite
directions…eg Oocytes of amphibians and in some insects …they are
giant chromosomes…
B-Chromosomes (also called supernumerary chromosomes, accessory
chromosomes, accessory fragments, etc.) are without obvious genetic
function and usually have a normal structure, are somewhat smaller than
the autosomes.

The chromosomes with a non-localized centromere are called as either
holocentric or holokinetic chromosomes
Duplication is replication…
Cytokinesis is the physical division of the cytoplasm whereby the nuclei,
cytoplasm, organelles and cell membrane of a single eukaryotic cell is
divided into two daughter cells containing roughly equal shares.
Mitosis ….identical parent cell…grow and repair,,,,involves karyokinesis
and cytokinesis…
Meiosis…double cell division…
First phase…interphase..preperation phase….cell grows by protein
production and has high metabolic activity…..g1 gap S synthesis and G2
phases..

G1…increases cell mass…longest…10 hr in 24 hr cell division…
S phase….dna and centromere replicated….5 hr..
G2 shortest…3 hr..
Prophase…nucleolus fades…chromatin condenses to
chromosomes..mitotic spindle appears as asters…centrioles moves to
opposite sides…nuclear envelope breaks..
Polar fibers, which are microtubules that make up the spindle fibers,
reach from each cell pole to the cell's equator. Chromosome begin to
migrate to center…
Metaphase…Chromosomes align completely at equatorial plane..nuvlear
membrane disappear fully..
Anaphase…the kinetochores separate and the paired centromeres in
each distinct chromosome begin to move apart to the cell poles
….each chromatids are called full chromosomes or daughter
chromosomes..
Telophase…Telo means end… encleavage furrow appears…nucleoli
(plural of nucleolus) and nuclei (plural of
Nucleus) reappear…nuclei form at two opposite poles….nuclear envelope
reformes….
Chromosome decondenses…
Cytokinesis,,,last stage…
Meiosis….The two stages of meiosis are Meiosis I and Meiosis II called
Reductional Division and Equational Division respectively. Before
meiosis q interphase which is similar to mitotic interphase…During
meiosis, the genome of a diploid germ cell undergoes two rounds of
division, resulting in four haploid daughter cells.
Meiosis I consist of four stages, Prophase I ,Metaphase I Anaphase I and
Telophase I.
Prophase 1…85 - 95 percent of the total time for meiosis
Prophase I can be broken down into 5 stages. Leptotene Zygotene
Pachytene Diplotene and Diakinesis
Leptotene or Leptonema Stage…..the chromosomes begin to condense.
A process called 'homology search' which precedes
Zygotene…or Zygonema….Homologous dyads (pairs of sister
chromatids) find each other and align themselves from end to end. This
pairing process is called Synapsis. Bivalent formation occurs which
equals to the number of haploid chromosomes..

Pachetene…synapsis complete…….Recombination nodules (chiasmata)
appear ….crossing over happens…
Diplotene…..synaptonemal complex break down….Formation of tetrad….
Diakinesis…nuclear envelope breaks Down….centrioles migrate away to
two poles…
Metaphase 1….
Spindle fibre attaches to chromosome…Tetrads align at the metaphase
plate.
Anaphase 1…Chromosome moves to opposite poles..
During this stage, the original maternal and paternal chromosomes
separate, thereby reducing the number of chromosomes from 2N to N
number, yet the sister chromatids remain together
Telophase 1…Completion of Migration..Cleavage furrow appears….later
next stage cytokinesis happens…
Interkinesis (Interphase II) is similar to interphase except DNA
replication does not occur during this stage.
Meoisis 2 is similr to mitosis… Telophase 2 chromosomes are called
monads..
In Mitosis…no synapse or chiasmata formation occurs,,,,nor the crossing
over,,,
1N1C

Golgi apparatus produces the acrosome containing enzymes and it takes its place
around the anterior end of the sperm head.
The polar bodies receive the same chromosome complement as the secondary oocyte
and ovum, but are not functional sex cells.
1

Monohybrid cross: A cross involving contrasting expression of one trait
.Dihybrid: have two pairs of different characters.
Mendel’s first principle, the law of segregation, referring to the non-
mixing of alleles in the hybrid and their subsequent segregation or
separation in the gametes in equal frequencies,….Universally accepted
Law..,.
F2 Dihybrid Genotypic ratio
According to the Principle of Independent Assortment, different pairs of
alleles are passed to offspring independently of each other. But not
possible when there is linkage…
N is number of heterozygotes,,,,,No of gametic combination is the no of
zygots…
Back cross is a cross between F 1 hybrid and one of its homozygous
parents
Test cross is crossing of an incompletely known genotype to a genotype
which is homozygous, recessive at all the loci under consideration.
If the tested individual is heterozygous and the pairs of factors are
segregating and assorting independently then the following phenotypic

ratio will be obtained. Mono hybrid test cross – 1 : 1 ……Di-hybrid test
cross - 1 : 1 : 1 : 1 ……Tri-hybrid test cross - 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1
The result of an environmental influence, which mimics the effect of a
specific allele, is referred to as phenocopy. A phenocopy is a one-time
event affecting the phenotype but not causing any transmissible change
in the genotype.
In Incomplete dominanace(mirabilis) and in Codominaance phenotypic
monohybrid ratio is 1:2:1
If the heterozygote exhibits a mixture of the phenotypic characters of
both homozygotes, instead of a single intermediate expression, then both
alleles are called co-dominant alleles. Eg MN blood group in humans
,,,,,colour of shorthorn Catlle…
Genes which affect the viability as well as the visible traits of an
organism are called lethal genes and the phenomenon is called lethality.
The phenomenon of two or more genes governing the development of a
single character in such a way that they affect the expressions of each
other in various ways is known as Gene Interaction .
Allelic and Non Allelic Type…
Allelic gene interaction
Expression of character is produced by interaction between alleles of a
single gene.
Complete dominance Incomplete dominance Co-dominance Over
Dominance
NON allelic are of two types…inter allelic and intra allelic…in non allelic
gene interaction Expression of character is produced by interaction
between two or more genes.
Lethal Gene is Intra allelic….
Interallelic includes.. Complementary Gene Interaction ……
Supplementary Gene Interaction ….. Epistasis…. Duplicate Factor …..
Inhibitory Factor ….. Polymerism or Additive Factor

Homozygous recessive lethal at either locus…1:2:2:4
Complete dominance at one locus and Incomplete dominance at another
locus (co-dominance)
EPISTASIS means standing upon…..When an allele of one gene masks
expression of alleles of another gene and expresses its own phenotype
instead ….The gene that is suppressed is called hypostatic and the
suppressor is called epistatic gene..
Recessive Epistasis or supplementary gene action
When one gene is homozygous recessive, it hides the phenotype of the
other gene.
( aa epistatic to B and b ) dihybrid..9;3;4….coat colour in rat….
Dominant Epistasis
When one gene is dominant, it hides the phenotype of the other gene.
( A epistatic to B and b ) 12:3:1,,,,,coat colour in dog..
Dominant and Recessive Epistasis ……..inhibitory gene action…
When either gene is dominant, it hides the effects of the other gene.
( A epistatic to B and b, bb epistatic to A and a, A and bb produce
identical phenotypes) 13;3…….anthyocyanin pigmentation in rice…
Duplicate Recessive Epistasis or complementary gene action
When either gene or allele is homozygous recessive, it hides the effect of
the other gene. 9;7…flower colour in sweet pea…
Duplicate Dominant Epistasis
When either gene is dominant, it hides the effects of the other gene.
15;1…..feather in shank…
Duplicate Interaction or polymeric gene action or additive
factors….when two genes are present together the action is enhanced
than one gene in recessive homozygous condition..9;6;1…..colour of
pig
Multiple alleles…..When more than two alternative alleles are
present for a gene.eg…colour of rabbit…total 6 alleles are there in
this case….agouti or full colour or brownish grey in wild type…
Silvery grey…mutant type…chinchilla
Another mutant Himalayan type…black at extremes with white
coat…this condition is called acro melanism …
Albino…lacks pigment…..so eyes are pink…another mutant…

EG 2…NATURE OF WING IN DROSOPHILA
Eye colour in Drosophila….wild type …red…here many alleles
produce 1 phenotypic effect…..
Such types of alleles, which act within the phenotypic range of each
other, are called isoalleles.
ABO blood group Carl Landsteiner…located on chromosome 9…
IA and IB,are co-dominant and IO is recessive to both IA and IB
Universal recipient AB….donor….O……if rbc antigen is a…then
serum antibody is b……for AB no serum antibody…
Sometimes a and b antigens are also found in body fluids…and they
are called as secretors…
Rh factor,,,,,Landstiener..85% people are Rh positive…as they have
rh antigens..
haemolytic disease of the newborn called “Erythroblastosis foetalis”
is due to Rh antigens…….does not create a problem in first
pregnancy…
The numer of genotypes possible in a diploid organism with 'n'
different alleles is given by the formula [n(n+1)]/2.
Lethal Genes..
First in yellow mice by CUENOT
Semi dominant lethal: (Incompletely dominant lethal, intermediate
lethal) …creeper legs in poultry….
Achondroplasia in Dexter cows..
Dominant lethals kill the individual either in homozygous or
heterozygous conditions and therefore is eliminated from the
population in the same generation in which it
arises…Eg…humtington disease..
Recessive lethals kill only when in homzygous stage. They are very
difficult to eliminate from the population. Heterozygous carrier
parents that produce a lethal effect could be used as testers to
identify others in the population.
Intermediate lethal genes are much easier to detect because all the
individuals will exhibit some phenotypic expression of the gene.
Conditionally lethal,,,,normally no problembut when exposed to
certain set of conditions it becomes lethal..

Sex linked lethal….hemophelia…the alleles responsible for
hemophelia are thus called semi lethal or sublethal gene because
they onlycause death of some individuals with affected genotypes…
Sex linkage refers to the association or linkage of a hereditary trait
with sex chromosomes ,,such triats are called sex linked
triats…,,most of the genes are assosciated with x chromosome as y is
smaller…
X linked disease…. These genes are associated with c chromosome
and absent in y chromosome. The characters are X linked characters
and their mode of inheritance is called X linked inheritance.occurs
more in males as they only fave one x chromosome…types X - linked
dominant, X-linked recessive or X - linked co dominant. …
X linked dominant…
In X-linked dominance, both males and females can display the trait
or disorder by having only one copy of the allele. Example :
Incontinentia Pigmenti (IP), X-linked hypophosphatemia, Fragile X
syndrome, Aicardi syndrome, Congenital hemidysplasia with
ichthyosiform erythroderma and limb defects (also known as
"CHILD syndrome"), Lujan–Fryns syndrome (LFS) also referred to
as X-linked mental retardation with Marfanoid habitus and Lujan
syndrome.
Eye colour in drosophila..F2 monohybrid 3;1
X linked recessive…
Since males have only one X chromosome, a single recessive allele on
that X chromosome will cause the disease. Females have two X
chromosome, so two copies of the recessive allele are required for the
disease to express in females …no father to son transmission…but
tranfers it to all daughtrs and are called as obligate carriers….
Transmission of the sex linked disease from affected males to male
grandchildren through carrier daughters is described as a "Nasse's
Law".
Sex linked traits in one parent passes to the opposite sex of the next
generation. This is known as “Criss Cross Inheritance”.
Example : Haemophilia, Color Blindness,

X Linked Co Dominant….Tortoise shell cat….or calico…
Y linked Gene…Y chromosome carries a few genes with visible
effects, called holandric genes..transmitted to son only…EG,,,Hairy
pinna….
A histocompatability gene (H-Y) present on the short arm of human
Y - chromosome. Various failures in the SRY ( Sex-determining
Region Y ) genes.
.
XY linked inheritance…located in homologous sections of both X and
Y chromosomes. …eg…In Drosophila melanogaster - bobbed bristles,
Xeroderma pigmentosum, Nephritis, Retinitis pigmentosa,
SEX Linked recessive inheritance is more shown in
heterogametes…whereas sex linked dominant in homogametes..
birds, moths, butterflies, silkworm and in some fishes
……homogametic male…..
Autosexing is when pure bred day old chicks can be sexed by their
different appearances when they have hatched ….eg barring
pattern in plymoth rock…rapid and late feathering in hapshire
A trait which is influenced by th sex of the individual is called sex-
influenced trait.
Eg red and mahagony colour in ayshire cattle,,,,,,,,baldness in
humans…horns in sheep……the triats are carried on autosomes....
Reciprocal cross…here the sex of parent showing particular triat is
interchanged….this is to determine the role of parents in inheritance
pattern…
Triats that are limited to one sex is called sex limited triats…eg,,,milk
production ,egg production, secondary sexual characters………….cock
feathering …influenced by h allele…Hen feathering HH.
LINKAGE.
TH MORGAN…..The phenomenon of inheritance of linked genes in
same linkage group is called linkage. ….strength of linkage between
genes depended on the distance between them on the chromosome…
the number of linkage group in an animal or plant is equal to the

haploid number of chromosomes present in one cell.
Complete linkage…only in male drosophila.closely situated genes..
Incomplete linkage…..they will not always stay together as
recombinants are produced during crossing over in meiotic
phase…so repulsion or trans configuration is also formed apart from
cis or coupling….
As age, temperature,radio active waves increase linkage decreases…
Genes are located in locus or loci…
Crossing over and independent assortments are two important
mechanisms for the generation of new combinations of genes …
Cytological evidence for crossing over……by stern
Crienghton observed linkage in maize…
After crossing over in meiosis terminalisation occurs which results in
breakage .. In a tetrad Each event of crossing over produces two
recombinant chromatids called as crossover chromatids and two
non crossover chromatids (original chromosomes).
Sinle cross over…here only one chiasma ia formed…
Double cross over....crossing over occurs at 2 points….so 2
chiasmata…
Two-strand double crossover occurs when both crossovers involve
the same two chromatids. Three-strand double crossovers are those
in which the second cross over involves one of the same two
chromatids as the first crossover plus one different chromatids
.Four-strand double crossovers occur when the second crossover
involves the two chromatids not involved in the first crossover
Another type is multiple Cross over…..
The maximum frequency of recombination that can result from
crossing-over between linked genes is 50 per cent.
Crossing over is less frequent near centromeres and the tips of the
chromosomes.
chiasma formation at one point prevents the chiasma formation in
the vicinity. This phenomenon is called Interference .
some chemicals decrease crossing over…colchicine.,selenium…some
increase..ethylmethane sulphonate…
Inversion of chromosome segments suppresses the crossing over
,,,inversion is the re arrangent of genes ,,,frequency of crossing over

decrease with aging…high temp plus radiation increases crossing
frequency…
Gene mapping" refers to the mapping of genes to specific locations
on chromosomes. …2 types…genetic or cross over mapping or
linkage mapping using linkage analysis..percentage of crossing is
directly propotional to distance between genes…..If there is 1 percent
cross over then distance is equal to 1 Map unit or Morgan unit or
Centimorgan (cM).
If a F1 hybrid having the genotype (Ab)(aB) produces 8% of “AB” and
8% of “ab” cross over gametes, then the distance between “A” and
“B” is estimated to be 16 Map units or Morgan unit or Centimorgan.
If the map distance between the gene loci “C” and “D” is 10
centimorgan, then 10% of gametes of genotype (CD)(cd) should be
cross over types, i.e., 5% “Cd” and 5% “cD”.
The two genes which have highest percentage of crossing over should
be placed on each end …The interference is inversely proportional to
the crossing over percentage.
Physical or cytological mapping…using molecular techs..
1st gene mapping ….sturtevant…..
Coincidence …it is the ratio between actual cross overs and expected
cross overs…if actual cross over zero…coincidence zero…interference
complete..
Coincidence + Interference = 1.0 …interfence and coincidence is
inversely propotional….
Mutations are sudden heritable changes in a gene or chromosome,
involving qualitative or quantitative alterations in the genetic material
itself.
Term introduced by Hugo de Vries…
The rate of mutation is increased either by using physical or chemical
agents and this process is called as Mutagenesis . . An agent that has the
ability to produce mutation is called the Mutagen . . The mutability of
some genes is influenced by other genes called Mutator genes ..for

fruitfly mutation rate is 1 in 1 lakh…In bacteria it is 1 in 1 lakh to 1 in 1
million..
DNA ;;adenine.;;guanine;;;cytocine;;;;thymine.;;.AT…CG
Forward mutation,,,mutation from wild to mutant…..its reversal is
called backward mutation or back mutation or reverse mutation or
reversion..
Two types of reversion,,,True reversion where there is reversion to
original genetic change,,
Suppression ….2 types…
mutation in a gene is suppressed by another mutation in the same gene.
In intergenic suppression a mutation in a gene is suppressed by another
mutation in the in different gene of the same chromosome or even in
another chromosomes gene.
Genes which suppress the activity of other mutated genes are called
suppressor genes
Another Classification …somatic and Germinal mutation…they have to
be dominant to cause a shift..
A and g are purines…normally keto forms of Thiamine and guanine and
amino forms of Adinine and cytosine occur and bond in this
fascion,,,,A;;T and C;;;G…but tautomerism can occur…The ability of a
molecule to exist in more than one chemical form is called tautomerism
…
The more stable keto forms of thymine and guanine and amino forms of
adenine and cytosine may infrequently undergo tautomeric shifts to less
stable enol and imino forms respectively. Hence different pairs like A
and C happens ….G and T pairing occurs..
Amino acid replacement types……Missense mutation….frameshift
mutation…nonsense mutation and silent mutation..
Mutations occurring at the first or second nucleotide position of a codon
is called Mis sense mutation
Any mutation that changes a codon into a codon that codes for a STOP
signal (termination codon) is called a Nonsense mutation
…UAA..UAG…UGA…
Any gene mutation which does not result in phenotypic expression is
called a Silent Mutation …eg…Mutation may occur in the third location

of the codon, the resulting new codon may still code for the same amino
acid. Or in some cases mutations occur at places where it is no longer
functional…
Frameshift Mutation is a type of mutation caused by insertion or
deletion of a number of nucleotides in a DNA sequence that is not
divisible by 3
Mutagenesis is a process by which the genetic information of an
organism is changed in a stable manner, either in nature or
experimentally by the use of chemicals or radiation.
Mutation can be induced and spontaneous…under spontaneous it occur
naturally in cells….in induced case it is induced by mutagens…that can
be physical or chemicals…
This can be natural or man made…
Physical agents eg..radiation which are of higher energy and wavelength
less than 100 nm..they are of 2 types..
Ionizing radiations (X-rays, protons, neutrons, and alpha, beta and
gamma rays, 32P, 35S or Cobalt-90 ) and
Non-ionizing radiations (UV light). …low energy…penetrate only surface
layer..and no ionisation induced..they act by excitation…The maximum
absorption of UV by DNA is at wavelength of 260 nm. UV absorption by
pyrimidines results in pyrimidine hydrates ( example : Cytosine hydrate
) and pyrimidine dimers ( example: thymine dimer )
CHEMICAL MUTAGENS….
The first chemical mutagen discovered was mustard gas (sulfur
mustard). some
mutagenic only to replicating DNA such as acridine dyes ( which bind to
DNA and increase the probability of mistakes during DNA replication )
and base analogs ( which are incorporated into DNA instead of normal
bases ).the other type is
mutagenic to both replicating and non-replicating DNA, such as
alkylating agents ( that transfer alkyl groups such as CH3-, CH3CH2- etc
to DNA such as
nitrogen and sulfur mustards, methyl and ethyl methane sulfonate
(MMS and EMS ), nitrosoguanidine (NTG) ) and deaminating agents (
nitrous acid ).
Base analogues…
The pyrimidine 5-bromo uracil is a thymine analog. 5BU…it cause AT to
GC transition and GC to AT transition…

The base 2-aminopurine is a purine analog ..adenine analogue…2AP
Acridine Dyes… proflavin, acridine orange and a series of compounds
called ICR170, ICR191 etc are powerful mutagens that induce frameshift
mutations…they produce kinks in Dna Double helix…
Deamenating Agents…nitous acid…
by the oxidative deamination of adenine, guanine and cytosine which
contain amino groups. Adenine is deaminated to hypoxanthine, which
base pairs with cytosine rather than thymine. Deamination of guanine
produces xanthine which pairs with cytosine just like guanine. So it is
not directly mutagenic. …It cause both At to GC and GC to AT
Deamination of cytosine results in uracil which pairs with adenine…. The
enzyme uracil-DNA glycosylase removes uracil from DNA creating an AP
site (apyrimidinic / apurinic site). Such AP sites undergo excision repair
…
MISCELLANEUS…Hydroxylating agents like hydroxyl Amine (NH2OH)
It hydroxylates amino group of cytosine to from hydroxylamine cytosine
which can base pair with adenine causing GC to AT transition. It only
cause GC to AT….
CIB technique is used in drosophila to find mutagenicity…..Attached X
chromosome method is also used in detecting sex-linked visible
mutation.
DNA repair Mechanism….by
Photo reactivation(they excise thiamine,cytosine, thiamine – cytosine
diamers….it occurs in light) , Excision repair or dark repair….thymine
dimers are removed from the DNA molecule and a new segment of DNA
is synthesized. , Post replication recombination repair…
Excision repair…happens in dark and in blue light…
First, an endonuclease recognizes the thymine dimer and cleaves the
phosphodiester bond near the site of damage. Then an exonuclease,
probably the 5’ 3 exonuclease activity of DNA polymerase-I removes a
segment of the strand adjacent to the endonuclease cut, including the
dimer. DNA polymerase-I then fills the gap using the complementary
strand as the template. DNA ligase then catalyses the formation of
phosphodiester linkage between adjacent nucleotides.

Start codon AUG
POINT MUTATION or Gene Mutation…
gene or point mutation is defined as any permanent change in a DNA
sequence that makes up a gene …this occurs by base pair or nucleotide
pair substitutions..
Transition replacement of a purine in one strand of DNA with the other
purine
Transversion… Purine replaced by a pyrimidine, or pyrimidine replaced
by a purine.
8 different transversions and 4 transitions are possible….
Frame Shift Mutations…
Structural
Chromosomal
abberations
Numerical.(change in no of chromosome is called
ploidy) Euploidy ( changes in whole chromosome sets ) Aneuploidy ( changes in
parts of chromosome sets )
Monoploidy or haploidy
Euploidy diploidy
Polyploidy..more than two sets are seen..tri,penta ,
hexa etc Autopolyploidy...colchicine
can induce
Allopoly ploidy
in monoploidy or haploidy….individuals with normal one set of chromosomes are
called haploids..diploids with one set are monoploids,,,eg….ant …wasp ..male bee
Autopolyploidy….occurs when an individual has more than two sets of
chromosomes..both from same parental species…. Union of two diploid (
unreduced ) gametes - Tetraploid …Somatic doubling ( tetraploid )

…Union of a haploid and a diploid gamete ( triploid ) ….A cross between
a tetraploid and a diploid parent ( triploid )
….Fertilization of an egg by two sperms ( triploid ) ,,,Autoploids with
even set of chromosomes can produce gametes,,,,but odd ones
cannot…eg..3n,5n….More seen in plants… Potato is a natural auto
tetrapolyploid ( 4n ). Autotriploids,,,,seedless watermelon grapes etc,,,
Allopolyploidy..when the individual has more than two copirs but from
different species…Does not occur naturally…
Aneuploidy….due to non disjunction of chromosomes…which means
failure in separation of chromasomes during anaphase resulting in
gametes with n+1 or n-1 chromosome number. This lates fertilises with n
to form 2n plus or minus 1
…monosomy occurs when one chromosome is lost from a pair…eg…2n-1
eg ..partial monosomy is found in cri-du-chat syndrome, which result
from loss of part of the short arm of chromosome 5. Mentally retarder
….cry as that of cat..
ving only
a single X chromosome (XO). Retarded…sterile…webbed feat…
Trisomy….2n +1 …there is trisomy of autosomes and sex chromosomes…
Trisomy of Autosomes..
Down syndrome (47, +21) or Trisomy 21 or 47,XX,+21 or 47,XY,+21
Trisomy 13 (Patau's syndrome) (47, +13) Extra fingers
…microphthalmia…cleft
Trisomy 18 (Edward's syndrome) (47, +18) ,,polydactyly,,,rocker bottom
feet..
Down syndrome…
also called Mongoloid idiots because their facial features resemble those
of Mongoloid race. In rare cases Down syndrome is also caused by a
Robertsonian translocation, which occurs when the long arm of
chromosome 21 breaks off and attaches to another chromosome at the
centromere …he or she become carrier of down syndrome..
Trisomy 18 (Edwards syndrome) is the most common autosomal
abnormality among live births after Down syndrome (trisomy 21).
Trisomy of sex chromosomes…..one chromosome x or y is added..
Triple X syndrome or trisomy X.. typically have tall stature by
adolescence ….

phenotypically normal and fertile females
Jacob's syndrome or XYY Karyotype,47,XYY syndrome ,YY
syndrome…same as xxx females….taller than usual…
Klinefelters syndrome. XXY ….47,XXY….
Gynacomastia and infertility follows….
Miscellaneous…Nullisomy…Fail to survive…2n-2
Structural changes in chromosomes
Happens in a chromosome or both the chromosome…
Intrachromosomal Aberrations
o Interchromosomal Aberrations
location
DELETION…found by bridges..results in loss of genes from
chromosome…
Terminal Deletion and Intercalary / Interstitial Deletion
Eg..Cri-du-chat syndrome, which result from loss of part of the short
arm of chromosome 5
a deletion of a portion of long arm of chromosome 21 leads to chronic
myeloid leukemia in human beings
Chromosomes with a deletion cannot be reverted back….if centromere is
invoved in deletion organism die..
When a chromosome loses is genes and later combine with another
chromosome and shows dominance, then it is actually pseudo
dominance…
Duplication..
In a diploid organism, the presence of an additional chromosome
segment per nucleus is known as duplication ,,,less problematic when
compared to deletion..

An altered phenotypic effect produced by change in position of a gene or
a group of genes is called position effect.
Inversion …An Inversion is a reversal in the order of a segment of a
chromosome within the chromosome, or a gene. Inversion suppress
crossing over..
Paracentric…if centromere not involved
Pericentric…centromere involved..
INTERCHROMASOMAL Aberations…
Translocation... Segment from one of two homologous chromosomes
breaks and binds to the other non-homologous chromosomes.
Non reciprocal..a part of one non homologous chromosome
transfer to
other …
Reciprocal… two non homologous chromosomes exchange
segments.
Non Reciprocal……Simple and shift type,,,,,
Simple…rare as the ends of cromosomes called as the telomeres are non
sticky in nature…this occurs by creation of a break at one end of the
chromosome and that part will join with another non homologous
chromosome..
Shift or intercalary chromosome translocation….this involves 3 breaks…
An interstitial segment of a chromosome is detached from it with the
help of two breaks and is inserted within the break produced in another
non-homologous chromosome.
In both cases the chromosome that loses the segment is called deficient
chromosome…
Reciprocal Translocation……two types …Homozygous or Heterozygous
type..
Homozygous…. In which both the homologous chromosomes exchange
parts with the two homologues of another pair of chromosomes…
Heterozygous… Are those involving only one member of each of the two
homologous pairs.

Cytogenetics includes the study of normal and abnormal chromosomes,
and investigation of the causes of chromosomal abnormalities.
Staining methods …solid staining, G-banding
G banding examples… Quinacrine banding (Q-banding), Giemsa
banding (G-banding), Reverse banding (R-banding), C-banding and
Nucleolar Organizing Region stains (NOR stains).
Some denotations in karyotyping….
r…ring…dup….duplication…t
..translocation…del…deletion…inv..inversion…
Type of molecular evaluation of chromosome by FLUORESCENCE IN
SITU AND COMPARATIVE GENOMIC HYBRIDIZATION
Spectral karyotyping (SKY) is a laboratory technique that allows to
visualize all pairs of chromosomes in an organism at one time, with each
pair of chromosomes painted in a different fluorescent colour.
Extrachromosomal inheritance…by Correns
Some self replicating genes (DNA) are present in the cytoplasm
(mitochondrial DNA and chloroplast DNA) . These are called
plasmagenes or cytogenes or plasmids or plasmons etc. The inheritance
of characters by plasmagenes is called Non-mendelian or Extra-
chromosomal or Cytoplasmic or Extra-nuclear inheritance. They
doesn’t obey mendelian rule….the transfer mainly occurs through
ovum…….
Eg… Plastid inheritance in Mirabilis .. Shell-coiling in snail, Limnea
Peregra …. Kappa particles in Paramecium Auralia…(they have kappa
particle in cytoplasm which transfers killer genes upon conjugation to
new daughters…the one which don’t receive them are non killers and are
sensitive to killers) …Cytoplasmic male sterility in maize …Sigma virus
in Drosophila melanogaster .. Milk factor in mice ..
The determination of the phenotype of offspring by the genotype of
female parent is called maternal inheritance or uniparental inheritance
or maternal effect. ..Example: Pattern of shell coiling in snail.

Gene Concept
Bateson had coined the term genetics
chromosome theory of heredity. By Thomas Hunt Morgan..
Avery, Macleod and McCarty ….DNA
James D.Watson and Francis H. C. Crick ,,,,Double Helix Str of Dna
"one gene-one enzyme" hypothesis was proposed by George Beadle and
Edward Tatum.
DNA is a ncleic acid and nucleotides are the building blocks.. The
structural unit consists of Pentose sugar (2’ deoxy ribose) phosphoric
acid and four nitrogenous bases: Purines- a double ring structure
Adenine (A) Guanine (G) Pyrimidines- a single ring Thymine (T)
Cytosine (C)
Base + sugar:::Nucleoside…phosphate grp is added to sugar to form
nucleotide..or nucleoside phosphate….nucleotides are named as dCMP.
dTMP..dGMP.. dAMP
The double helix measures 20Aº (2.0 nm) in diameter.
Chargaff’s rule …amount of thiamine and adine equal…nucleotides are
bonded by phosphodiester bond..
In each polynucleotide chain there are a 5’ phosphonyl group (5’-p) at
one end and 3’-hydroxyl group (3’-OH) at the other ..
Each chain makes one complete turn every 34 A0. The bases are spaced
at 3.4 A0 such that there are ten base pairs per helical turn. …AT double
bond…GC trible bond…
The major groove occurs where the backbones are far apart, the minor
groove occurs where they are close together
Coding sequence…exons….non coding…introns,,,,,they are removed by
splicing during protein synthesis….
Central Dogma DNA >RNA>Protein…this is unidirectional…..and
irreversible..
Mechanism by which gene express phenotype is gene expression…
Dna to mRNA by Transcription…mRNA is translated to protein in
ribosomes with help of tRNA…
Tri Hybrid Cross …. 27:9:9:9:3:3:3:1
Multiple allelism-more than two alternative form of a gene located on
the same locus of the homologous chromosome are known as multiple
alleles. Multiple alleles are found in the population, not in the single

individual. ABO blood group in human(3 alleles); Coat colour in
Rabbit(4 alleles); Eye colour in Drosophila(15 alleles)
Pleiotropic gene: a gene with multiple phenotypic effects or a single
gene that controls more than one trait
muscling gene in cattle
POPULATION GENETICS….by JL Lush..
Members in population breed together..
Gene pool is defined as the sum total of genes present in a Mendelian
population
Gene flow is the transfer of gene from one to other..
Allele frequency is also called gene frequency…(p+q=1),,,,
During selection allele frequency shift to one direction…
Random mating is also called Panmixia..
HARDY- WEINBERG LAW
by Wilhelm Weinberg Godfrey Harold Hardy.
Both gene and genotype frequencies in a population remain constant
generation after generation when the population is large; mating is at
random and in the absence of selection and natural selection,genetic
drift,gene flow, mutation and migration. When this remain constant
the population is said to be in Weinberg equilibrium orgenetic
equilibrium….It is a non evolutionary model..
p2 + 2pq + q2 = 1 …p is frequency of dominant gene,,,2PQ is frequency
of heterozygote or carriers…Q square is the frequency of recessive
homozygote…
For a single locus with two alleles: the maximum frequency of
heterozygote will be 0.5. Then p=q=0.5
In case of multiple alleles without dominance the law can be applied..
Possible no. of genotypes in multiple allelism = N (N+1)/2;
where N is the no. of alleles
For a three allele system, the equilibrium genotype frequencies can be
expressed algebraically as p + q + r = 1
(p + q + r) 2 = p2 + q2 + r2 + 2pq + 2pr + 2qr = 1
In case of sex linked genes…
P dash f is the frequency of the allele in new males…..

The difference in gene frequency between the sexes will be halved as
compared to the previous generation ,,,,sex linked genes does not follow
the equilibrium….
also when two loci are considered together the genotype frequencies will
reach equilibrium after several generations of random mating. As no of
loci increases the time to reach the frequency also increases.. Under
random mating, loci that are linked approach equilibrium more slowly
than do loci segregating independently.
Non random mating are of 2 types assortative and
disassortative…assortative is the mating of individuals with same
phenotypes,,,,
There are 2 process affecting the genetic equilibrium…they are
systematic process and dispersive process…..systematic process affect in
all population and its direction and amount can be
calculated…eg…mutation, migration, selection,,,,,In case of dispersive
process its direction cant be predicted and it affects small
population,,,,eg Genetic drift
Migration,,,,
The gene frequency in new population will depend on the original gene
frequency of the population and the difference in gene frequency
between the immigrants and native (qm – q0) and the proportion of
immigrants …. Δ q = m (qm – q0) …delta q is q1 - qo
where n2 is the new immigrant….
The contribution of offspring to the next generation is called fitness of
the individual or adaptive value or selective value.
Founder effects – occurs when a population is initially established by
small number of breeding individuals … Bottleneck effect – occurs when
a population is dramatically reduced in size ..these two happens in small
populations…
Two genes are said to be alike by descend when they have a common
ancesotor without mutation,,,,,Autozogous,,,,,,

Two genes are alike by state or allozygous when they have similar
nucleotids….
Inbreeding coefficient is probability that the two genes at any locus in an
individual are identical by descent. Denoted by F.. Panmictic index is the
probability that genes at any single locus are independent by descent P
= (1 – F)
Increment in inbreeding ….. ΔF = 1/2N
Variace of vhange of Gene frequency
The effective population size is based on the number of genes in the
population that can be passed on to the next generation. The symbol is
Ne (N-effective)
Rate of inbreeding is inversely proportional to the effective population
size.
Continuously varying characters are called quantitative characters or
metric characters (Example: economically important traits such as
height, weight, milk yield, wool yield, egg production etc.) and variation
in them is called quantitative variation or continuous variations.
Quantitative traits are controlled by multiple genes, each segregating
according to Mendel's laws. . The inheritance of quantitative traits or
poly genes is called Quantitative inheritance, Multiple factor inheritance,

Multiple gene inheritance or Polygenic inheritance.
The phenotypic value of a given quantitative trait is the yield of the
individual with respect to the trait. Denoted by P….
The phenotypic value (P) of an individual is determined by the combined
effect of the genotypic value (G) and the environmental deviation (E) ….
For a single locus, the mean environmental deviation in the whole
population is taken to be zero. So the mean phenotypic value is equal to
the mean genotypic value.
G = A + D + I G - Genotypic value A - Additive value D - Dominance
deviation and
I - Interaction or epistatic value ,,,,,( add I if more than 1 loci is involved)
Breeding value = the value of genes to progeny .. Genetic value = the
value of genes to self …..If an individual is mated to a number of
individuals at random, from the population then its breeding value is
twice the mean deviation of the progeny from the population mean

(since the individual only contributes half of the alleles to its offspring)
…
With random mating, the mean breeding value is zero.
When a single locus only is under consideration, the difference between
the genotypic value (G) and the breeding value (A) of particular genotype
is known as dominance deviation.
The differences in phenotypic values of quantitative traits among
individuals of a population are referred to as variation. Expressed in
variance…
Dominance deviation and interaction deviation are non
additive…phenotypic variance is always positive…where as phenotypic
value can be negative..
intangible variation are non genetic variation …whose cause is
unknown…
Genetic Varience by Ronald Fischer
Genetic environment Co relation….
When G x E correlation is present, the phenotypic variance is increased
by twice the covariance of genotypic values and environmental
deviations and equation becomes VP = VG + VE + 2 covGE
If Genetic environment interaction is present
Vp = VG + VE + VGE.
P = G + E + IGE
Additive genetic effect..occurs when alleles of a single gene combine so
that the combined effects equals the sum of individual effect…non
additive involve dominanace or epistasis..

Heritability in narrow sense is used to refer per cent or proportion of the
phenotypic variation between individuals for a particular trait that is due
to differences in the additive genetic effects of the trait. h2= VA/VP
..
It represents the percentage of genetic progress made in the next
generation when superior individuals are selected as parents
The ratio VG/VP is called the heritability in the broad sense or the
degree of genetic determination .. Heritability in the broad sense is a
measure of the strength of the relationship between phenotypic values
and genotypic values.
Heritability is a population measure, not a value to be associated with an
individual animal. It varies from population to population and from
environment to environment. Heritability ranges from 0 to 1.
Heritability….egg size…feed coversion…fat and protein percent in
cattle== .5
Milk yield.. .25 Hatchability and egg production .1
On the whole, the characters with the lowest heritability are those most
closely connected with reproductive fitness …
0.3 or more - high … 0.3 - 0.1 - intermediate / medium …..below 0.1 -
low
The value of an individual judged by the mean value of its progeny is called breeding
value of the individual …
on average parent transfers half its breeding value to its offspring. …
it is called progeny difference or transmitting ability.
PD = ½ BV
VP = VA+VD+VI +VE. These components are called causal components of variance.
The degree of resemblance between offspring and parent is measured by regression
coefficient and that between full or half sib is measured by correlation
Parent and Offspring ……
Or offspring and mid parent…. ½ VA
Half sib ¼ VA
Full sib ½VA+ ¼ VD + VEc
The coefficient of relationship between half sib is 0.25.

The cov between half sib is due to ¼ VA+ 1/16 VAA.
The cov between parent and offspring is 1/2VA+ 1/4 VAA.
The coefficient of relationship between full sibs is 0.50.
Repeatability is defined as the correlation between measurements on the same
animal for traits, which are measured more than once.
Example….Lactation milk yield, Fleece weight in sheep, and Litter size in swine
Repeatability is Used to estimate the future performance of animals or Most
probable Producing Ability (MPPA).
Repeatability…
Egg weight 0.90
Egg shape 0.95
Shell thickness 0.65
Milk yield 0.50
Fat % 0.60
Grease fleece
weight
0.40
o 0.0 - 0.3 : Low .. 0.3 - 0.6 : Medium .. 0.6 and above : High
Correlations are used to describe the relationship between two traits in a
population
The values for a correlation coefficient range from –1 to +1.
Pleiotropy is the property of a gene whereby it affects two or more
characters, so that if the gene is segregating it cause simultaneous
variation in the character it affects.
Co Related response is how the improvement of one character will cause
simultaneous changes in other character.
PHENOTYPIC (rP), GENETIC (rA) AND ENVIRONMENTAL CORRELATION (rE)
BETWEEN IMPORTANT ECONOMIC TRAITS
Low - 0.2 to - 0.4 0.2 to 0.4
Medium - 0.4 to - 0.6 0.4 to 0.6
High - 0.6 and above 0.6 and above

National Bureau of Animal Genetic Resources (NBAGR), Karnal,
Haryana.
Central Institute for Research on Buffaloes, Hissar, Haryana
National Equine Research Centre, Hissar, Haryana.
Central Sheep and Wool Research Institute (CSWRI), Avikanagar,
Rajasthan.
National Camel Research Centre, Bikaner, Rajasthan.
Central Institute for Research on Goats, Mukdoom, UP
Indian Grass land and Forage Research Institute, Jansi, UP
Central Avian Research Institute (CARI), Izatnagar, Uttranchel.
National Research Centre on Yak, Dirang, Arunachal Pradesh
Horse was probably the last to be domesticated.
Bos longifrons (African Cattle).
Sus scrofa (European), Sus vittatus (wild boar)
the origin of horses were from Przhevalski’s Horse (Steppe Horse) ,Celtic
Pony and Libyan Horse
Father of Animal Breeding. …Robert bakewell
AI ……..Spallanzani ,,,used dogs…
Ivonoff…AI in cattle
Martin Cline created a transgenic mouse
Ian Wilmut cloned a sheep called “Dolly” from somatic cell of an adult
ewe
cloned calf from a Friesian cow “Jafferson”
2010 Cloned a buffalo calf named ‘Shresth’ at National Dairy Research
Institute, Karnal, India.
caffer (African buffalo), bubalis (Indian reverine buffalo or water
buffalo), grunniens (yak), bonasians (European bison), gaurns (gaur),
frontalis (gayal), sondaians (banteng)
Bos primigenins – Strong horns, narrow fore head. Example-Angus,
Ayrshire, Short-horn, Holstein Friesian, Red Poll. … Bos longifrons –
Broad and dished fore head. Example - Jersey, Guernsey, Brown Swiss….
Bos brachycephalus – Short and broad head. Example - Canadian,
Hereford, Kerry.
SUB ORDER ..
Horse…perissodactyla…. Camel, Pig,,,,,Artiodactyla….
cristatus (Indian wild pigs)
E.zebra (the zebra)
salvanius (Himalayan pigs)

poultry class Aves..Order…Galliformes …anseriformes in
duck…Family..Phasianidae…
dick is anatydae….Breed>>>>variety>>>>lines or strains…
asses are of purely African origin
Rabbit…order…Lagomorpha ………Family….Leporinae
Camel Family is bovidae
Hare…Lepus Negricolli.. camel….Dromedaries bactrianus
Yak ,Mithun Family….Pecora….true ruminants..
Bos frontalis …Mithun
Yak (Bos grunniens)
The average daily gain in buffalo calves is 478 gram
Canary colouration of wool During Autumn season….fetches low
amount….this is due to staining with alkaline sweat….
selection is called the keystone of the arch in animal improvement
phenotype, unlike the genotype, changes with time
Heritability of a trait may be defined as that portion of the phenotypic
variation that is due to additive gene action
The offspring of outstanding parents often have a tendency to regress
towards the average of the breed from which they were selected. …..
Galton’s law of filial regression towards mean…
heterozygous individuals that are superior could be used for market but
not for breeding
artificial selection is divided into different methods, they are Tandem
method, independent culling level and selection index or index selection
selection based on its own performance is called mass selection or
individual selection.
comparison of performance based on its own individual performance is
called performance test …selection based on phenotype.. most of the
progress in livestock improvement can be credited to individual
selection.
comparing the individual’s own phenotype with that of the average of all
the individuals within a group from which it is selected and is called trait
ratio.

In a random mating population, half-sibs have a relationship coefficient
of 0.25 and full-sibs have a relationship coefficient of 0.5.
If the records of the individual are included in the family average and
used as a criterion for selection, it is known as family selection. If the
individuals’ records are not included in arriving at the average, then it is
known as sib selection.
Collateral relatives are those not directly related to an individual as
ancestors or progeny
If environmental correlation among the phenotypes of the sibs are zero,
then t = Rh2
T is degree of correlation…
The accuracy of selection never exceeds 0.5
The selection based on pedigree is only useful than of individual
selection only when heritability is moderate or low.
When the pedigree data provides information on the phenotypic and
genotypic merit of the ancestors then it is called performance
pedigrees
Progeny testing attempts to evaluate the genotype of an individual on the
basis of its progeny’s performance.Mainly used for males…
Tandem method of selection….Breeder selects and improves only one
trait at a time until it reaches an acceptable level, and then he shift to
another and so on for a third
ELECTION INDEX OR INDEX SELECTION OR TOTAL SCORE
METHOD……
It is the most effective method of selection. Selection index is a single
numerical value within the total scores given for each trait considered in
the selection.
The response to selection is the difference of mean phenotypic value
between the offspring of the selected parents and the whole of the
parental generation before selection …R or G = h2 S ………..s is
selection differential…
The average superiority of the selected parents is called as selection
differential..
It is defined as the difference between the mean phenotypic value of the
individuals selected as parents and the mean phenotypic value of all the
individuals in the parental generation before selection. ..The factors

affecting the response to selection are heritability, selection differential
and generation interval. Maximum gain will result when the selection
differential (S) and the heritability (h2) are high and the Generation
Interval is low.
When the response to selection has stopped, the population is said to be
at “plateau” or “selection limit”.
Inbreeding is a system of mating where by the mates are more closely
related than the average members of the population.
Grading: is the practice of using registered sires of a given breed on
scrub or native females generation after generation.
Crossbreeding is the mating of pure bred animals from two different
breeds.
Out crossing is the mating of animals of the same breed but with no
traceable relationship for several generations back in the pedigree.
Mating system based on phenotypic resemblance or dissimilarity known
as assortative mating ,,,eg…external appearance…..so there is negative
and positive..
Top Crossing.. It refers to the use of highly inbred male with females of
base population or non-inbred population.
Cross breeding: It is the mating of two individuals from different breeds.
Line crossing : It usually refers to crossing of inbred lines within a
specific breed.
Inbreeding is also called as close breeding…Inbreeding is also known
as genetic assortative mating while out-breeding is also known as
genetic disassortative mating.

Close Inbreeding: Such as mating between sibs or between parents and
progeny in order to achieve inbred lines with relatively high degree of
homogenisity …Half sib mating is less risky and provides
homogenesity… …
Line breeding: It is a system of mating in which the relationships of an
individual or individuals are kept as close as possible to some ancestor.
In general line breeding is a milder form of inbreeding.
parents are more likely to be pre-potent than non-inbred parents.
Prepotency is the ability of the individual to stamp its characteristic on
its offspring to such an extent that they resemble their parents more
closely than in usual …
It is not transmissible from parent to offspring.
Strain and line are created through inbreeding..... strain is created first
…later line…
If inbreeding effects are large, the type of gene action is non – additive: if
inbreeding effects are small , then the type of action is additive.
MF = Mo - 2 F pqd …..inbreeding depression is – 2F pqd which
depends on dominance (d), inbreeding coefficient (F) and relative
frequencies of alleles (p & q).
Rxy =Σ [(1/2) n+n’ ]… n = No. of generations between X and the
common ancestor or the no. of times the halving process has undergone
between X and common ancestor
n’ = No. of generations between Y and the common ancestor or the no. of
times the halving process has undergone between Y and common
ancestor.
Relation btw cousin …12.5 %
Relation btw half first cousin 6.25….Half-first cousin: whose one grand-
parent is common
Relationship between double first cousins 25%.....Double first
cousin: whose four grandparents are common
The average percentage increase in homozygosity or decrease in
heterozygosity in an inbred animal in relation to an average animal of
the same breed or population is known as coefficient of inbreeding
symbolised by ‘F’.also called degree of inbreeding…Fx =
[(1/2)n1+n2+1] n1 = No. of generation from the sire of X back to the
same common ancestor
n2 = No. of generation from the dam of X back to the same common
ancestor

Full sib..25…half sib 12.5…The coefficient of inbreeding 25 means that
the animal “X” is 25 less heterozygous than the animals in the herd.
If common ancestor is inbred you have to use the formula…Fx =
[(1/2)n1+n2+1 (1+FA)]
First find Fa
Outcrossing…Out crossing usually applies only to mating within a pure
breed. If two lines or flocks within the same breed are separated for four
or five generations and the sire from one herd is used in another herd
that amounts to out crossing
Line crossing usually refers to crossing of inbred lines within a specific
breed. Line crossing takes advantage of both increased homozygosity
within a line and the difference between lines
.
Back Cross….It is the mating of a cross bred animal back to one of the
pure parent races, which were used to produce it.
Grading up is the continual use of sires of one pure breed starting with
foundation females which were of another breed or no particular breed
at all (Non-descript or Mongrel). Marked improvement in crosses if sires
from a particular breed (A) are repeatedly back crossed to another breed

/ non-descript animals (B). Five generations are sufficient to raise the
level of inheritance of breed A to 96.9% (0.969) in the fifth generation. 7
to 8 crosses are done…
Foundation stock 0
First generation 50
Second generation 75
Third generation 87.5
Fourth generation 93.75
Fifh generation 96.875
Sixth generation 98.4375
Seventh generation 99.23875
Eight…. 99.6
Pien-niu (Cattle ×Yak) Zebroid (Zebra × Horse) Mule (Mare × Jack)
Hinny (Stallion × Jennet) f) Cama (Camel × llama) Tigon: -Male tiger
× female lion Liger: - Male lion × female tiger
Geep is a chimera produced by combining the embryos of a goat
& a sheep. Chimera has four parents but a hybrid has only two parents
In India, the best method for improvement of buffalo breeds is
selective breeding.
Inbred line - developed from two generations of full-sib mating. A line
is called inbred line, if it has minimum inbreeding coefficient of
0.375 or 37.5%

In crossing - Crossing of two different inbred lines derived from the
same breed. In cross breeding - Crossing of the two different inbred
lines derived from different breeds.
Cross breeding is mating of two individuals from different breeds.
Types…. Single two way cross or Single cross …… Two different
breeds are crossed with each other to produce an F1……..
Three way crosses (A,B, C) The first generation crossbred females
are crossed with females of the third breed, then using the hybrid vigor
of dam.
Double cross or Four way cross
Back cross (AB)
o Usually the F1 females are back crossed to one of the parent breeds. In
this cross, the maternal heterosis is exploited
Criss crossing (Reciprocal back crossing)
o Breeds A and B are crossed to produce F1 generation, then F1(AB)
females are back crossed to B and F1 (AB) males back crossed to breed A
and so on.
Three way rotational cross
-
__________________________________________________
_______
HETEROSIS
Heterosis is a phenomenon in which the crosses of unrelated individuals often result
in progeny with increased vigour, much above their parents.

Heterosis (H) = [ (Mean of F1 offspring) - (Mean of parents) /Mean of Parents ] x
100
Heterosis is caused by heterozygosity of genes involving non-additive effects, which
mainly includes dominanace, over dominance and epistasis.
HF1 = dy2 and HF2 = 1/2 dy2
General combining ability (GCA) is the mean performance of F1 expressed as a
deviation from the mean of all crosses and it is due to additive genetic variance.
Specific combining ability (SCA) is the superiority of a particular cross over the
average GCA of the two lines and it is due to non-additive genetic variance. GCA and
SCA are expressed as variance and not as values. For measuring the general
combining ability, top crossing is followed.
Complementarity is due to additive gene action and it is not heterosis
Heterozygotes are less influenced by environmental factors than the homozygotes.
This phenomenon is termed as “buffering”, which means that the organisms’
development is highly regulated by genetics.
Those traits expressed early in life, such as survival and growth rate to weaning seem
to be affected most by heterosis. Feed-lot performance as measured by rate and
efficiency of gain after weaning is moderately affected. Heterosis has very little effect
on carcass traits. Traits, which show the greatest degree of heterosis are the same
ones which show the greatest adverse effects when inbreeding is practiced. Highly
heritable traits seem to be affected very little by heterosis; whereas, those which are
lowly heritable are affected to a greater degree.
..
Heterosis will be higher when breeds are crossed than lines within the
breeds are crossed…..
Heterosis is much employed to produce commercial stock where the
individual merit is promoted, but the breeding value is lowered.
Sire evaluation….
Different sire indexes……
Simple daughter average index…..
EQUIPARENT / INTERMEDIATE / DAIRY BULL INDEX / YAPP’S
INDEX ,,……… SI = 2D – M………..
MOUNT HOPE INDEX by Goodale…………
o S = D + (D - M) x 3/7 if D>M
o S = D - (M - D) x 7/3 if M>D

o S = D + (D - M) x 3/2 if D>M
o S = D + (M - D) x 2/3 if M>D
Heizers index based on milk production
Gifford index
Regression index or Rice index…..
Tomar index,….
Corrected daughter average index or krishnas index
Diary Search index or sundareshan index…
Herd mate comparison by Henderson and Carter
BEST LINEAR UNBIASED PREDICTION (BLUP) by
Henderson…..
Here records are adjusted for all known sources of environmental bias using
adjustment factors and the adjusted records are used for selection…..
Corrects the data automatically for all known non genetic sources
Estimates also the breeding value of individual having no records
BLUP is the best method for evaluating the breeding value of bulls and rank the sires
according to their genetic merit …
Most accurate method is progeny testing
Project Directorate on Cattle, Meerut
In progeny testing milk from the daughter is measured from 15 th day and
measured for 305 days
The Central Frozen Semen Production and Training Institute (CFSP&TI) located at
Hessarghatta (Bangaluru)
Breed of choice for imoroving draught animals….tarparkar
Buffallo….Murrah
National Project for Cattle and Buffalo breeding (NPCBB)…during 9th year plan….
OPEN NUCLEUS BREEDING SYSTEM The major disadvantage
of this system is the disease control that have a major
influence
It consists of three-tier multiplication systems, namely the nucleus tier
(selector and supplier ….10 to 15%), multiplier tier (multiplier and tester
population…30 to 40%) and the commercial tier 50%.

In CNBS The direction of the gene flow in traditional system is always
one sided i.e from nucleus tier to multiplier and then to the commercial
tier. And never back to nucleus tier from commercial tier.
CGBS (COOPERATIVE GROUP BREEDING SYSTEM)
adopted a sire breeding nucleus to breed replacement sires for itself and
the associated field level herds. Cows or buffaloes replacements are
reared in both the nucleus and associated herds at field level.
small ruminant population can be improved through Open Nucleus Breeding Scheme
(ONBS).
Sheep parameters to be considered… Tupping
“At no point, crossbreeding of goat should be resorted”
RECURRENT SELECTION: Given by Hull (1945):
tester.
rge number of individuals are crossed with this line and their progeny are
evaluated.
their progeny are tested in the crosses on the inbred tester.
and over.
RECIPROCAL RECURRENT SELECTION: Given by Comstock et al
Present breeding policy og goat… Up grading of non descript with improver breeds of
the area is rcommended
egg number, size and weight which are moderately heritable
H.F. will be used through out the state in crossbreeding programme.

Khaki Campbell is best egg producing breed in ducks
Ex-situ conservation is comparatively more convenient, economical and easy with
the application of modern reproductive technologies.
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Statistic means Political state…
Biostatistics is also called Biometry meaning "biological measurement
A set or collection of objects pertaining to a phenomenon of statistical
enquiry is referred to as universe or population or census
When a few units are selected from a population, it is called as a sample
The quantitative or numerical characteristic of the data is called as a
variable
Constant is a numerical value, which is same for all the units in the
population
Attribute refers to the qualitative character of the items chosen
A statistical measure pertaining to a population is called as a parameter
and pertaining to a sample is called Statistic…
If a variable takes an intermediate value between any specified interval,
it is called as a continuous variable and if it only takes integral values
then it is called discrete or discontinuous variable…

When the investigator himself collects data its called primary
data,,,others through available sources like journals newspaper etc are
secondary data,,,,
Direct personal observation
Indirect personal Observation….through third
persons called witness
Data collection through agents, local reporters etc:
Appoints agents
Data collection through questionnaires: ********
Original Data is called Raw data…when grouped into classes its grouped
data…
Types of classification….Numerical in case of quantitative…..Descriptive
in case of Attributes….Qualitattive eg breed…………….Spatia or
Geographical class…..Temporal or chronological class….
Class frequency or frequency is the number of observations in that class.
When the Class Intervals are continuous, it is called True or Inclusive
Class Interval.
When there is a small gap between the upper boundary of any class and
lower boundary of sucessive class, then the Class Interval is called
Apparent or Exclusive Class Interval. 1 – 10,,,,,10-20
Class Mark is the midpoint of the class.
Statistical Tables are special tables used by statisticians in interpreting
the results of statistical analysis. The commonly used tables are ‘t’ tables,
z table, F table etc
Yules Rule and Sturge rule is to calculate no of classes..
Histogram is vertical bar diagram without gap between the bars.
Ogive is cumulative frequency curve .. The x co-ordinate of the point of
intersection of less than and greater than cumulative frequency curve is
the median.
Frequency curve is smooth and frequency polygon have straight lines…

Lorenz curve is a modification of the Ogive when the variables and the
cumulative frequencies are expressed as percentages.
Two dimensional (or) Area Diagram eg.. Pie diagram ,Square diagram
and rectangle diagrams
Three dimensional (or)Volume diagrams
One dimensional….Line Diagram, bar diagram, Component Bar Diagram
or Sub divided Bar Diagram, Superimposed or Multiple bar diagram ,
Percentage bar diagram
Bar Diagram … It is the simplest of all statistical diagrams
Two type of averages…
mathematical averages or algebraic averages (arithmetic geometric and
harmonic mean) and positional averages or averages of position (mode
and median)
(weighted AM)
The geometric mean is the nth root of product of ‘n’ items of a series ….
GM will be zero if one or more of the values are zero
geometric mean is the antilogarithm of the arithmetic mean of the
logarithmic values ..
Logarithm of geometric mean is the arithmetic mean of logarithmic
values.
Harmonic mean is the total number of items of a variable divided by the
sum of the reciprocals of the items.
Harmonic mean is the reciprocal of arithmetic mean of the reciprocal
values.

Mode is the size of the most frequent item in a large set of data. Thus
mode is the value of that variable which occurs most frequently or
repeats itself the greatest number of times.
For assymetrical case…… Mode = 3 median – 2 mean
A distribution can have more than one mode. If it has got one mode, it is
called unimodal distribution; if it has got more than three modes, it is
called multi-modal or poly-modal distribution. ….
The sum of the deviations of the items from the mean is equal to zero.
AM > GM > HM
For a symmetrical distribution, AM = median = mode
For a positively skewed distribution, AM > median > mode (short tail on
the left)
For a negatively skewed distribution AM < median < mode
When dispersion is not significant then the average appears to be a true
representative figure of the series ….The measurement of the scattering
of item in a distribution about the average is called a measure of
variation or dispersion. Differrent measures of dispersion Range …
Quartile Deviation .. Mean Deviation(M.D) …Standard Deviation (S.D)
Range= upper limit – Lower Limit….
dispersion for range or the ratio of range (R.R) …R.R = (H-L) / (H+L)
Quartile Deviation is based on quartiles which are points which divide
the data into four equal parts. …It is also known as semi-inter quartile
range ….
The difference, Q3 – Q1 is called inter quartile range and Quartile
Deviation is given by (Q3 – Q1) / 2
Relative measure of QD is known as the quartile co-efficient of
dispersion (QC).
Mean deviation or average deviation in a series is the AM of the
deviations of the various items from an average (mean, median or mode)
of the series taking all deviations as positive.

The relative measure of Mean Deviation is known as mean coefficient of
dispersion or coefficient of mean deviation and is obtained by dividing
the MD by the average from which it is computed
Standard Deviation is the most perfect and widely used measure of
dispersion ….
It is the root mean square of the deviations measured from the mean.
Relative measure of standard deviation is known as coefficient of
variation (CV or COV) and is defined as SD / Mean.
Higher CV indicates greater variability and less CV implies better
consistency of data.
Sheppard correction is to correct standard deviation…
Square of standard deviation is called as variance. It is the mean square
deviation.
The difference between the sample mean and population mean is due to
sampling and it is called sampling error or standard error.
Probable Error(PE) …. PE = 2/3 SD
QD = (2/3) SD = PE
MD = (4/5) SD
Std. deviation = 5/4(M.D.)
Skewness indicate the form or type of the distribution.
if the right tail is longer than the left, the distribution is positively
skewed; if the left tail is longer than the right, the distribution is
negatively skewed.
Pearsonian measure of skewness
It is given by, mean – mode or 3 (mean - median)

the coefficient of skewness is equal to skewness devide by SD
Bowley's measure of skewness
is given by Q3 + Q1 – 2M ….coefficient of skewness is…
Based on Moments …skewness is…
Kurtosis is the measure of Peakedness….It indicates the degree of
flatness or peakedness in the region or area relating to the mode of
frequency curve ….
The normal curve is known as mesokurtic.
A curve more peaked than normal curve is leptokurtic and the curve
which is flatter than the normal curve is platykurtic
Kurtosis is equal to β2 - 3
β2=3 for a normal curve
β2<3 for platykurtic curve
β2>3 for leptokurtic curve
Probability is a ratio taking values from 0 to1. It can never be negative. If
an event is an impossible event, then the probability is 0. If an event is
certain to occur, then its probability is 1.
Mutually exclusive events… If the occurrence of an event completely
avoids the occurrence of another event, then the events are said to be
mutually exclusive.
Sample space…Represent the set of all possible outcomes of a
phenomenon
If one tries to base the probability of an event on past experience of
certain outcomes based upon a long series of experiments (that is, on the
basis of statistical data), then the probability is known as statistical or
empirical probability.
THEORY OF TOTAL PROBABILITY OR ADDITION THEOREM…The probability of
occurrence of one or other of a set of mutually exclusive events is the sum of the
probabilities of occurrence of the separate events of the set …P(A or B) = P(A) + P(B)
MULTIPLICATION OR COMPOUND PROBABILITY THEOREM …The probability
of simultaneous occurrence of a set of independent events is the product of the
separate probabilities of those independent events.

If p is the probability of the event, the probability that it will occur in exactly x out of
n cases is *nCx . q*n-x . p*x.
Binomial probability was discovered by James Bernoulli and hence it is also called
Bernoullian distribution. It's mean is np and variance is npq, where q=1-p, SD = root
of npq) ; Variance is always less than mean ….. p represents probability of success…It
is symmetrical, when p=q=½….When n is large and p is small such that np is
constant, the binomial distribution tends to a Poisson distribution . It is also called as
the law of improbable events………Mean is approximately equal to
variance………..Binomial and Poisson distributions are the more useful theoretical
distributions for discrete variables…it ranges from zero to infinity.. When n is large
and p=q=½, the binomial tends to become a normal distribution…The normal
distribution is the most useful theoretical distribution for continuous variable….
Also called Gaussian distribution or laplacian distribution or probability cuve….–∞ to
+∞…It is a symmetrical distribution, mean=median=mode…MD = 4/5 σ….skewness
zero…Kurtosis is 3. It is mesokurtic. If mean =0; SD=1 then the normal distribution
is a standard normal distribution…
Correlation is the strength of relationship or the intensity of association between two
variables. If two variables vary in such a way that as one increases (or decreases), the
other also increases (or decreases), then the correlation is said to be positive or
direct. (eg.) feed intake and growth rate of animals. If two variables vary in such a
way that as one increases, the other decreases and vice versa, then the correlation is
said to be indirect or negative (eg.) litter size and birth weight of piglets.If there is no
relationship between the two variables, they are said to be independent or
uncorrelated.
A measure of correlation free from units of measurements is called coefficient of
correlation. It is denoted by ’r’, r takes values from –1 to +1. When r = +1, the
correlation is perfect and positive, r = -1, the correlation is perfect and negative, r =
0, there is no correlation..
In multiple correlation, we study the correlation of one dependant
variable over all the other independent variables, (eg.) milk yield vs. first
lactation period, food supplied, age etc…… In partial correlation we study
the relationship between two variables, assuming that the other variables
are constant. (eg) correlation between the weight of broiler and feed
intake assuming the other factors like area provided, labour used,
medicinal cost etc. as constant.
The graphical depiction of a linear correlation presents a straight line
and its functional relationship is represented by the relation, y = a + bx,
where ‘a’ and ‘b’ are constants…A perfect linear correlation may be
positive or negative. Thus, its numerical coefficient will be either +1 or –
1. These are the limits of correlation….. Thus, coefficient of correlation
cannot be greater than +1 or less than –1. If the correlation is imperfect,

its graphic exposition will be non-linear.it will not form straight line and
value lies between -1 and +1….
There are different ways of studying correlation…scatter diagram or
scattergram or scatterplot or dot diagram is a chart prepared to
represent graphically the relationship between two variables.Corelation
graph is also similar…but both of then does not offer numerical
value…Among mathmetical method most commonly used is Pearsonian
coefficient of correlation…
Rank correlation is another method also called as Spearman’s rank
correlation coefficient as it was due to the statistician Spearman.
Square of correlation coefficient (r2) is defined as coefficient of
determination….
Coefficient of non-determination (1 – r2) /////This is also called as
unexplained variations…..
Regression is the amount of dependence of one variable on the other.
This gives the rate of change of one variable with respect to
another.introduced by Francis Galton….The simple linear regression is
of the form y = a + bx, where ‘b’ represents the slope of the line (also
called as regression coefficient ) and 'a' the intercept of the line.
Regression coefficient gives the rate of change in the value of dependent
variable ( y ) for a unit change in the independent variable ( x ).
Product of the regression coefficients is the square of correlation
coefficient.
Standard error or sampling error is standard deviation of the sample
means.ie.. SD/root n
Point estimate: is a single value which is used to estimate the population
parameter
Interval estimate: is an interval in which population parameter lies
between. It is also called fiducial limit or confidence interval.
Parameter is the statistical measure pertaining to the population, while
statistic is the statistical measure pertaining to the sample. The
reciprocal of standard error is taken as a measure of reliability or
precision of sample.. As n increases, SE decreases and hence precision
increases.
Livestock census….the first Census was organized during 1919-
1920…latest is 20th census…

Random sampling or probability sampling
lottery…random number table
o Stratified sampling
o Systematic random sampling
o Cluster sampling
o Multistage sampling.
Non random sampling or non probability sampling include
Stratified random sampling…..In this method, the population of size ‘N’
is subdivided into a definite number of non overlapping and distinct sub
population of sizes N1, N2, …, Nk .This procedure of dividing the
population into distinct sub populations is called stratification and each
sub population is called as a stratum. Between strata, there should be
greater diversity or variability.,,,within strata they are more
homogenous…so it is used in cases where the units are more variable….
Systematic random sampling….This consists of selecting only the 1st unit
at random, the rest being selected according to some predetermined
pattern involving regular spacing of units.
Cluster sampling…total population is divided depending on the problem
under study, into some recognisable subdivisions named as clusters and
simple random sample of these clusters is drawn.
In Multistage sampling, sub samples are created with in clusters…hence
clusters form first stage sampling unit…..the sub samples later created
forms second and third stage sampling units…
Purposive or deliberate or subjective or judgment sampling… It is the
one in which the investigator takes the samples exclusively at his
discretion.
Convenient sampling….. If the investigator chooses the samples at his
convenience, it is called convenient sampling.
Quota sampling…It is a type of judgment sampling wherein quotas are
setup according to some specified characteristics such as ‘this much in
this group’, ‘this much in other group’ and so on.

Test of significance is a statistical procedure followed to test the
significance of the difference between statistics and the parameter or
between any two statistics.
Hypothesis…. Any statement made about the population
Null hypothesis…. It is the hypothesis under test or initial hypothesis
proposed . It may or may not be true. It is usually denoted by Ho. Null
hypothesis is never proved.
Usually we will have two levels of significance. 5% and1% level of
significance…………… 5% level of significance means that, if this
experment is repeated under identical conditions 100 times,then the
chance for this conclusion to go wrong is five out of 100 ………. 1% level of
significance means that, if this experment is repeated under identical
conditions 100 times,then the chance for this conclusion to go wrong is
one out of 100 .
Statement contrary to null hypothesis is alternate hypothesis and is
denoted by H1.
Degrees of freedom(d.f)… The number of observations which are free to
move or free to vary.
Null hypothesis may be true but we reject it by our test which is Type I
error.
Null hypothesis may be false but we accept it which is Type II error.
Level of significance is the probability of type 1 error
In parametric tests the tests will be attached to distribution,,,,, Normal
deviate test or large sample test or Z test,,,,,,,,,,,,Students t test or small
sample test………………Chi-square test………… Variance – ratio test or F-
test
Z test is carried out, when sample size is > 30.
| Z | < 1.96, we say that Z is not significant and Ho is accepted.
We denote this by Z = ( )NS.
| Z | > 1.96, Z is significant and Ho is rejected. We denote this
by Z = ( )*.
| Z | > 2.58,Z is highly significant and Ho is rejected. We
denote this as Z = ( )**.
T TEST…. DF is N-1
If | t | < table value of t for (n-1) d.f. at 5% level t is non-significant and
HO is accepted. We denote this as t = ( ) N.S.

If | t | > table value of t’ for (n-1) d.f. at 5% level ‘t’ is significant. Ho is
rejected, we denote this as t = ( )*.
If | t | > table value of‘t’ for (n-1) d.f. at 1 % level t is highly significant.
Ho is rejected. We denote this as t = ( ) **
When the sample are independent to each other the test done is called
unpaired T test…
The range of t distribution is negative to positive infinity
CHI SQUARE TEST…
This test is used in the case when observed frequencies are to be tested
for their fit with expected or theoretical frequencies or to test whether
two factors of classification of a set of individuals presented in the form
of two- way table are independent or not. This test is also used to test the
observed number of progenies in a genetic experiment to fit in
Mendalian laws of heredity.used to find goodness of fit…
If the calculated χ2 is less than table χ2 for the respective degrees of
freedom at 5% level. χ2 is not significant which is denoted by χ2 = (
)N.S.i.e., Ho is accepted. The fit is good.
If calculated χ2 is > table χ2 for the respective d.f. at 5% level χ2 is
significant and denoted by χ2 = ( )*. Ho is rejected. The fit is not good or
theoretical frequencies are not according to theory.
If calculated χ2 is > table χ2 for the respective df at 1% level χ2 is highly
significant and denoted by χ2 = ( )**. Ho is rejected. The fit is not good
or theoretical frequencies are not according to theory.
………………Here df is no of classes - 1
The degrees of freedom for r x c contingency table is (r-1) (c-1)….R is no
of rows and C is no of colums……
F test or varience ratio test…..
If cal | F | < tab F for d.f. = (n1-1), (n2-1) at 5% level, F is not significant
,denoted by F=( ) N.S. Ho is accepted.
If cal | F | > tab F for d.f. = (n1-1), (n2-1) at 5% level, F is
significant,denoted by F = ( ) *. Ho is rejected
If cal | F | > tab F for d.f. = (n1-1), (n2-1) at 1% level, F is highly
significant,denoted by F = ( ) **. Ho is rejected.

Experimental error describes the failure of two identically treated
experimental units to yield identical results.
BASIC PRINCIPLES OF EXPERIMENTAL DESIGNS
Randomization………..
Replication……..
Local Control…It refers to the skillful logical way of grouping the
experimental units in such a manner that there is more uniformity
within the same group and there is greater variability between different
groups.…
In completely randomised design (CRD), there is no local control
applied, while in randomised block design (RBD) local control is applied
in one direction with
one criterion and in Latin square design (LSD) in two directions with two
criteria.
When no treatment is applied over a group of experimental units we
consider these units to constitute a control group.
Auxillary variable are characters that are not being altered by the
treatments applied but may have influence on the characters under
study.
COMPLETELY RANDOMIZED DESIGN (CRD)
Simplest among all…This is the design in which the treatments are assigned
completely at random to the experimental units or vice versa. i.e. it imposes no
restrictions on the allocation of treatments to the experimental units. CRD is
preferred when all the experimental units considered for the experiment are known
to be homogeneous.
Degree of freedom for treatments is t-1 and for total CRD is N-1
If calculated F< table value of F for (t-1), (N-1)d.f. at 5% level, F is not significant. H0
is accepted. All the treatments are alike.
If calculated F> tab F for (t-1), (N-1)d.f. at 5% level F is significant.F=( )*. Ho is
rejected.
if calculated F> tab F for (t-1), (N-1) d.f at 1% level F is highly significant. F=( )**. Ho
is rejected ….
If F is significant or highly significant, critical difference between treatment means is
to be worked out.

RANDAMIZED BLOCK DESIGN (RBD) …Experimenter
arranges this into homogenous blocks….
RBD is an equi-replicated design.
RBD is a better design than CRD, as this will have greater precision of
the estimates and greater efficiency of the designs.
If calculated F< table value of F for (t-1),(b-1)(t-1) d.f. at 5% level, F is not
significant. H0 is accepted. All the treatments are alike.
-1),(b-1)(t-1) d.f. at 5% level F is
significant.F=( )*. Ho is rejected.
-1),(b-1)(t-1) d.f at 1% level F is highly
significant.F=( )**. Ho is rejected.
Biological assay or bioassay is a form of experiment for the estimation of
the potency of a substance or comparing the efficacy of two or more
substances by means of the reaction that follows their application to
living matter. preparations of known strength is called the standard
preparation and the other is of unknown strength and is called test
preparation. Then the ratio R=Zs/Zt is called the relative potency of the
test preparation. when R is less than 1 the potency of the test preparation
is smaller than that of the standard preparation. If R = 1,the two
preparations are equi-potent.
An assay with two preparations containing the same effective ingredient,
which is responsible for the response, is called analytical dillusion assay.
An assay with two preparations which have a common effect but do not
contain the same effective ingredient, is called a comparative dillusion
assay.
There are three main types of bio-assays. They are
o Direct assays
o Indirect assays based upon quantitative responses and
o Indirect assays based upon quantal responses
In direct assays the tolerance doses, the doses below which no response
occurs for the standard and test preparations, are measured directly as
soon as the response has occurred.
Indirect assays basd upon quantitative responses…The responses may be
a change in weight, a change in analytical value etc.. The relationship
between the dose and response drawn as a frequency curve is known as
the dose response curve.
Under indirect assays based on quantitative responses there are two
types assays. They are,

o Parallel line assays, The parallel line assays are those in which the
relationship between the quantitative response and log dose is linear.
The lines for the standard and test preparations shall be parallel. A
parallel line assay in which the standard and test preparations have an
equal number of doses and an equal number of subjects for each dose is
called a symmetrical parallel line assay. Otherwise, it is called an
asymmetrical parallel line assay…When we have k doses we then have 2k
point symmetrical parallel line assay…The most popular design is the 4-
point assay.
o Slope – ratio assays………….here the relative potency is estimated from
the ratio of the slopes (regression coefficients) of the fitted lines. we shall
consider here only assays with (2k + 1) doses. We may have 3 – point, 5
– point, 7 – point, etc., assays. The 3-point assays is the most efficient
design.
The assays in which the responses are qualitative are known as quantal
response assays….also known as all – or – none responses…………….Here
the strength of a preparation is charactersied by the median tolerance or
the dose that induces 50% responses.
If the response is mortality it is called median lethal dose and is denoted
by LD50.
If the response is not mortality, it may be called median effective dose
(ED50), median knock down dose (KD50), median antifeeding dose
(AD50) ….
The most commonly used measurement is LD50.
The ratio LD50 / ED50 is called therapeutic index.
LD 50 is estimated by Dragstedt – Behren’s method , spearman karber
method etc
……………………………………………………………………………………
Anova by Ronald fischer…to analyse difference among means…..
Punched cards, Punched paper tapes (used in olden days), magnetic
tapes, magnetic diskettes, magnetic drums, keyboards, compact disc,
etc., are some of the input devices.
Central processing unit consist of control unit, alu and register
unit…registers are used to store instruction and data for further use.
The main memory is of the type of Random Access Memory (RAM) and
the auxiliary memory is of magnetic memory. RAM can retain the
information as long as there is electric power.

ICAR ANIMAL SCIENCE SHORT NOTES.pdf

ICAR ANIMAL SCIENCE SHORT NOTES.pdf

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