Cattle Breeding by 9PH1V8

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									                                  Cattle Breeding
                                     Booklet No. 200
                             Animal Husbandry-Cattle: CAS - 5
Contents
Preface
I. Introduction
II. Factors Affecting Breeding Efficiency
III. Management Practices to Improve Breeding Efficiency
IV. Selection and Culling
V. Choosing Traits for Selection
VI. Systems of Breeding
VII. Improvement of Dairy Cattle in India.

Preface

        Cattle rearing is an important subsidiary to agriculture in India. It has been playing a
significant role in India's rural economy. Despite its vast cattle population, India's place
regarding cattle productivity is at the rock-bottom vis-a-vis other countries, especially western
ones. One of the major reasons for this is the lack of good breeding stock as well as
technologies in our villages. This booklet describes different aspects of scientific breeding of
cattle and buffaloes.

K.T. Chandy, Director, Agricultural & Environmental Education.

I. Introduction

        Reproduction is an important consideration in the economics of cattle production. In the
absence of regular breeding and calving at the appropriate time cattle rearing will not be
profitable. A healthy calf each year is the usual goal. This is possible only by increasing the
reproductive efficiency of the animals.

        Successful reproduction encompasses the ability to mate, the capacity to conceive and
to nourish the embryo and deliver the viable young ones at the end of a normal gestation period.
In fact, interruption in this chain of events leads to failure of the cow either to conceive or the
embryo to die or to have a premature delivery of the foetus.

        The reproductive efficiency is a complex phenomenon controlled by both genetic and
non-genetic factors, the non- genetic factors being climate, nutrition, and level of management.
The reproductive efficiency varies not only between species and breeds but also among the
animals within the Same breed. Even the best feeding and management can not coax
performance beyond the genetic limit of an inferior animal. Improving the genetic merits of
livestock populations is important at all levels of management. A sound breeding programme is
a necessary part of the total animal production system. It is absolutely imperative to improve the
productive capacity and physical appearance of the animal population.

II. Factors Affecting Breeding Efficiency
The factors which influence the breeding efficiency of cattle are as follows:

1. Number of ova
        The first limitation on the breeding efficiency of fertility of an animal is the number of
functional ova released during each cycle of ovulation. Ovulation is the process of shedding of
ovum from the Graffian follicle. In the case of cow, usually a single ovum is capable of
undergoing fertilization only for a period of 5-10 hours. Therefore, the time of mating in relation
to ovulation is important for effective fertilization.

2. Percentage of fertilization
         The second limitation is fertilization of ova. Failure to be fertilized may result from
several causes. The spermatozoa may be few or low in vitality. The service may be either too
early or too late. so that the sperms and eggs do not meet at the right moment, to result in
fertilization.

3. Embryonic death
         From the time of fertilization till birth, embryonic mortality may occur due to a variety of
reasons. Hormone deficiency or imbalance may cause failure of implantation of fertilized ova
which die subsequently. Death may occur as a result of lethal genes for which the embryos are
homozygous. Other causes may be accidents in development, over-crowding in the uterus,
insufficient nutrition or infections in tile uterus.

4. Age of first pregnancy
       Breeding efficiency may be lowered seriously by increasing the age of first breeding.
Females bred at a lower age are likely to appear stunted during the first lactation, but their
mature size is affected little by their having been bred early.

5. Frequency of pregnancy
        The breeding efficiency can be greatly enhanced by lowering the interval between
successive pregnancies. The wise general policy is to breed for the first time at an early age
and to rebreed at almost the earliest opportunity after each pregnancy. In this way the lifetime
efficiency is increased. Cows can be rebred in 9-12 weeks after parturition.

6. Longevity
       The length of life of the parent is an important part of breeding efficiency, because the
return over feed cost is greater in increased length of life. Also, it affects the possibility of
improving the breed. The longer the life of the parents, the smaller the percentage of cows
needed for replacement every year.

III. Management Practices to Improve Breeding Efficiency

        Some of the management suggestions which will tend to improve breeding efficiency of
cattle are listed below.

1. Keep accurate breeding records of dates of heat, service and parturition. Use records in
predicting the dates of heat and observe the females carefully for heat.
2. Breed cows near the end of heat period.
3. Have females with abnormal discharges examined and treated by veterinarian.
4. Call a veterinarian to examine females not settled after three services.
5. Get the females checked for pregnancy at the proper time after breeding.
6. Buy replacements only from healthy herds and test them before putting them in your herd.
7. Have the females give birth in isolation, preferably in a parturition room and clean up and
sterilize the area once parturition is over.
8. Follow a programme of disease prevention, test and vaccination for diseases affecting
reproduction and vaccinate the animals against such diseases.
9. Practice a general sanitation programme.
10. Supply adequate nutrition.
11. Employ the correct technique.
12. Provide suitable shelter management.
13. Detect silent or mild heat, by using a teaser bull.

IV. Selection and Culling
        Selection and culling are the two sides of the same coin. Selection is the process in
which certain individuals in a population are included for becoming the parents of the next
generation. Automatically some are excluded for the purpose which are culled. Natural selection
has been going on since ages where animals which were stronger, which had better
survivability and which were in more unison with the environment around them, found a better
chance to reproduce. Thus certain genes for certain characters got more chance to be selected
to form individuals in the subsequent generations. Since domestication of cattle, man has been
looking for superior phenotypes in traits useful to him and selecting such animals to form the
parental generation. This is man made artificial selection. Now man has progressed one step
further in making estimates of genotypes from the study of phenotypes and making use of that
information (in artificial) selection.

A. Selection methods
        There is only one way to select and that is to "keep the best and cull the poorest. The
various selection methods are techniques for identifying or estimating the genetic values of
individual candidates for selection. The procedure discussed here apply to selection for
quantitative trails.

1. Performance testing
        Performance test is a measure of the phenotypic value of the individual candidates for
selection. Since the phenotypic value is determined by both genetic and environmental
influences, the performance test is an estimate, not a measure of the genetic value. The
occurrence of this estimate depends upon the heritability of the trait i.e. on the degree to which
the genetic value is modified by the environmental influences.

Advantages
a. Among simple procedures, the performance test is the most accurate.
b. Environmental influences can be minimised by testing candidates for selection in the same
pen or in similar environmental conditions.
c. The measure is direct, not on a relative basis.
d. All candidates for selection can be tested in contrast to progeny testing where only a parent
can be tested.
e. Generation intervals are usually short.
f. Testing can usually be done on the farm under normal management conditions.

Disadvantages
a. Accuracy become low when heretability is low.
b. Phenotypes are not available for one sex or in sex limited traits such as milk yield.
c. Traits which are not expressed until maturity may become expensive or difficult to manage by
performance tests since most selection decisions must be made before maturity.
       Performance tests should be the backbone of most selection programmes. Although
much publicity has been given to other selection methods, it remains a fact that most of the
progress in livestock improvement to date has been due to selection on the individual's Own
phenotype i.e. performance test.

B. Pedegree selection
        A pedegree is a record of an individual's ancestors including its parents. This information
is valuable because each individual possesses a sample half of the genes from each parent. If
we can precisely know an individual's phenotype, little is gained by considering pedegree in
selection. Pedegree considerations are useful when we do not have sufficient accurate records
of production of the individual. Also, it is useful in the early selection when the traits in question
might not have expressed themselves. It is also useful for selection of males when the traits
selected for are expressed only by the female (sex-limited) such as milk production in dairy
cattle.

Advantages
a. It provides information when performance tests are not available for the candidates.
b. It provides information to supplement performance test information.
c. It allows selection to be completed at a young age. Pedegree records may be used to select
animals for performance or progeny testing in multi-stage selection scheme.
d. It allows selection of box sexes for sex-limited traits i.e. bulls can be selected on the milk
records of their female relatives.

Disadvantages
a. Accuracy, relative to alternative selection procedures is usually low.
b. Too much emphasis on relatives, especially remote relatives, greatly reduces genetic
progress.
c. Progeny of favoured parents are often environmentally favoured.
d. Relatives often make records under quite different environments, thus introducing non
random bases into the selection system.

C. Progeny testing
         In this method we evaluate the breeding value by a study of the expression of the trait in
its off springs. Individuality tells us what an animal seems to be, his pedegree tells us what he
ought to be, but the performance of his progeny tells us what he is. Progency testing is, of
course, a two-stage selection system because some preliminary selection determines which
animals first produce progeny followed by further culling of these which produce poor progeny.

Advantages
a. High accuracy when many progeny are obtained.

Disadvantages :
a. Long generation interval.
b. Requires high reproductive rate.
c. Low selection intensity.

D. Show ring selection
       Selection on the basis of show ring performance has had considerable value in the past.
Essentially this selection has been directed towards bringing the conformation of the animal to
some ideal conformation. This improvement has been based on two goals: (i) improvement
conformation, and (ii) correlated response.
       Improvement of conformation has economic value because a part of the sale price is
determined by the conformation of the individual. The ideal type was chosen so that, in the
opinion of the judges, the animal possessing this conformation was most likely to be a profitable
producer. In other words, the judges were attempting to stress traits of conformation which are
corrected with productive ability.

        With the advent of record keeping it was found that direct selection for performance traits
resulted in much faster progress than selection through correlated conformation traits. Also,
when subjected to intensive study, many of the correlations between performance and show
ring were found to be of non-genetic origin. If the correlations are of genetic origin, direct
selection for performance should improve conformation as well as the reverse situation. The
show ring has been a good forum for discussion of what constitutes ideal type and good
management and has produced dramatic changes in the conformation of some species. This
has resulted primarily from education of the breeders, however, for most animals which are
presented in the ring are good and selection differential among these animals is usually so small
as to produce little change.

Advantages :
1. It enables breeders to exchange ideas and experience.
2. It allows comparisons among superior animals both within and between breeds.
3. It allows new breeders to make contact with established breeders.

Disadvantages:
1. Emphasis is usually placed on traits of little economic importance.
2. Clever fitting and showmanship can mask defects of various kinds.
3. Differences between exhibited animals are usually small.
4. Conformation and production traits usually have low genetic correlations.

V. Choosing Traits for selection
       Many factors enter into the choice of traits to be selected for. The following ones are the
most important.
1. The goal of the selection programme
2. The habitability of the traits
3. The economic value of improvement in each trait.
4. The range in variation of each trait.
5. Correlation among the traits.
6. The cost of the selection programme.

1. Selection goals
        Often the goal of the selection programme makes the choice of traits quite obvious. The
breeder of the race horses must select for speed if he is to be successful and his choice of traits
are limited to alternative ways to measure speed. Similarly, the breeder of dairy cattle generally
sets out to breed cows with superior milk production cl1aracteristics. Thus, his choice of traits is
specified by his selection goals.

2. Heritability
        Heritability is defined to be the fraction of the superiority of parents which is, on the
average, transmitted to their off-springs. To explain habitability in simpler words: Heritability tells
us how much of the observable differences in the animal is caused by genes and how much by
environment.
Heritability for the same characteristics may vary from one population to another and also may
vary from one characteristic to another even ink the same population. The ability to recognise
the breeding values or transmitting abilities of animals is closely associated with heritability. If
the heritability is high for a trait, we can proceed straight way to adopt a system of mass
selection of superior animals, with little attention to pedegree information, collateral relatives,
progeny test or inbreeding and genetic improvement in that trait is low, genetic progress may be
disappointing with mass selection and greater attention should be paid to pedegree records,
family information and use of progeny tests.

D. Variability of the trait
         Selection operates on the variability in expression of the trait uniform for a trait. there will
be little selection response because any selected groups of parents will not be much better than
those not selected. Some traits are much more valuable than others. thus the innate variation of
the traits should be carefully considered in choosing traits for selection.

      Variation can be increased by improving exotic types and sometimes this can result in
new combination of genes which are superior to either parent type.

E. Correlated traits
       Sometimes traits tend to be inherited together. These correlations may arise in several
ways.

1. The traits may be of different measures of some underlying trait. For example. weight and
height are both measures of body size. thus taller animals are usually heavier and these two
traits are said to be correlated.
2. If the same genes produce response in several traits. those traits will be correlated. This
condition is referred to as pleiotrophy.

        Correlated responses are common. Selection for increased milk yield produces a
correlated decrease in the per cent of fat in the milk of dairy cows. Thus. both direct and
correlated responses result from selection and some correlated responses are positive while
others negative.

        Correlated response may be advantageously used in selection programme. For example
feed efficiency is expensive to measure because it requires both weight gain and feed intake on
each individual, whereas weight gain requires neither feed weight nor individual feeding.

        In summary. definite goals are essential for a successful selection programme. The
success in achieving these goals depends on the existence of genetic differences. the degree to
which phenotype differences are heritable and the correlated responses in other traits. In
comparing the selection programme, the breeder must evaluate the value of the expected
response and the cost of the programme relative to the costs and responses of alternative
selection programmes.

VI. Systems of Breeding

        The ultimate aim of the breeder is to evolve outstanding and improved type of animals
which can render better service to man. Selection and system of breeding constitute the only
tools available to the breeder for improvement of animals. Since new genes can not be created
though they can be recombined into more desirable groupings.
Systems of breeding has been broadly divided as under
1. In breeding -breeding of the related animals.
2. Out breeding -breeding of the unrelated animals.

A. lnbreeding
         Inbreeding is a mating system in which individuals mated are more closely related than
the average of the population from which they come. It means the mating of males and females
which are related. Animals deemed to be related only when they have one or more ancestors in
common on the first 4-6 generations of their pedegree. The intensity of inbreeding depends
upon the degree of relationship. Close inbreeding denotes mating of closely related individuals
like dam to son (mother x son) or sire to daughter (father x daughter) or full brothers to full
sisters.

        In breeding makes more pairs of genes in the population homozygous. Wherever there
is inbreeding. there will be one or more common ancestors from which, part of the gene
samples (gametes) have arisen.

Inbreeding can again be divided into following groups:




1. Close breeding
       This means the mating of full sister to full brother or sire to his daughter or dam to her
son. These types of matings should be only when both parents are outstanding individuals, and
then only at the increased risk of bringing undesirable recessive genes into homozygous form in
the progeny.

Advantages
1. Undesirable recessive genes may be discovered and eliminated by further testing in this line.
2. The progeny are more uniform than out-bred progeny.

Disadvantage...
1. The undesirable characteristics are intensified in the progeny if unfavourable gene
segregation occurs.
2. It has been observed that the progeny become more susceptible to diseases.
3. Breeding problems and reproductive failure generally increase..
4. It is difficult to find out the stage of breeding at which it should be discontinued in order to
avoid the bad effects of the system.

2. Line breeding
        This means the mating of animals of wider degrees of relationship than those selected
for close breeding. It promotes uniformity in the character. Homozygosity is not reached so
quickly as in close breeding. Neither desirable nor harmful characters are developed so quickly.
It is a slowed method for the fixation of hereditary outstanding bull or cow and the progeny is
mentioned as being line-bred to certain ancestors.

Advantages
1. Increased uniformity.
2. The dangers involved in close breeding can be reduced.

Disadvantages
1. The chief danger in live breeding is that the breeder will select the animal for pedegree giving
no consideration to real individual merit. This may in some cases result in a few generations
which receive no benefits from selection.

3. Consequences of in-breeding
       The effects of both close breeding and line breeding are similar. The only difference is in
the degree of their intensity. They are more intense in close breeding and less so in line
breeding. These may be described as follows.

1. It increases homozygosity (like alleles) and decreases heterozygosity (dissimilar genes) and
hence favours the development of genetic uniformity amongst the animals.
2. It is the best method of getting true strains from unknown stocks as it sorts out the characters
in the homozygous condition and thus help in the selection of undesirable individuals and culling
of the undesirable individuals. Strains which breed true are not obtained in animals. however,
and in plants are obtained only when close inbreeding is accompanied by intense selection.
3. The outward effects of in-breeding may include the following

a. Effect on growth rate
       With the exception of a few laboratory animals, some moderate decrease in growth rate
and mature weight has been noted. The studies on rats on the other hand have shown that they
withstand inbreeding (up to 100 generations over 40 years) without any apparent bad effect on
growth rate. The reproductive rate of rats is very high, however, relative to farm stock.

b. Effect on reproductive performance
       In almost all the cases a reduction in the reproductive efficiency has been noted. It may
delay testicular development and puberty, reduce gametogenesis or increase the embryonic
death rate.

c. Effect on vigour
       It has been noted that the death rates among the in-bred groups of animals are higher
than those in out-bred ones. They are also adversely affected by environmental conditions.
They have higher percentage of Runs (animals which are undesirable due to various reasons).

d. Effect on production
       Production traits usually show moderate decrease with increased inbreeding.
e. Appearance of abnormalities
       Hereditary abnormalities or lethal factors are likely to appear more often in the inbred
animals than in the out bred ones.

        Of the two components of inbreeding i.e. close breeding and live breeding, it is safer to
go for the later one. A few recommendations have also been made With regard to them.
It is recommended for seed stock breeds in the fo11owing situations.

I. Better than average herds.
2. If the owner is well informed regarding both its possibilities and pitfalls.
3. Herds with two or more sires to keep the inbreeding level under control and not allowing it to
rise to dangerous levels.
4. For some experimental purposes. It is further recommended ,that the herds of the following
types should never be subjected to inbreeding.
1. The grade or commercial herds.
2. Poor herds below average.
3. Herds with one sire and where the owner has got no knowledge about genetics.

         Inbreeding is useful if we want to evolve a more uniform line in any animal species. A
line is often desirable for scientific purpose when animals or plants for a number of lines can be
mated to get a breed with many desirable qualities. However, that is the job of a scientist or
precisely a geneticist. A fine line of animals may not be commercially profitable at all. A farmer
is, therefore, advised not to conduct this experiment inbreeding unless he knows genetics.

B. Out breeding
        Out breeding is the breeding of unrelated animals and this involves the following types of
breeding.
1. Out crossing
2. Cross-breeding
3. Hybridization
4. Grading up

       The genetic effects of out-breeding are opposite to those of inbreeding. Whereas
inbreeding increases homozygosity, out breeding tends to make more pairs of genes
heterozygous.

Therefore, out-bred animals are less likely to breed true than are in-bred animals.

1. Out-crossing
        Mating of unselected animals within the same pure breed is termed out- crossing. The
animals mated have no common ancestors on either side of their pedegree up to 4 -6
generations and the off-spring of such a mating is known as the outcross. Traits which are
largely additively genetic and which have a high heritability, respond quickly to out crossing.

       In a period of many years, the various breeds in many western countries registered
progress mainly though a system of out-crossing in which the best available, but unrelated sires
were continuously selected for use on the females in a herd or flock.

1. Advantages
1. This methods is highly effective for characters that are largely under the control of genes with
additive effects i.e. milk production, growth rate in beef cattle, etc.
2. It is an effective system for genetic improvement if carefully combined with selection.
3. It is the best method for most herds.

2. Cross breeding
       It is the mating of the animals of different breeds. It is generally used where the crossed
progeny is directly marketed and are not needed for breeding and further multiplications. It has
become quite common in pigs and in the production of hybrid chickens. With the beef cattle also
it is practiced to a certain extent. Cross-breeding for milk product has been tried with varying
degree of success. It is generally used for production of new breeds. The method of cross-
breeding are described below.

a. Criss -crossing
       When two breeds are crossed alternatively the method is known as criss-crossing. This
method is proposed for utilising heterosis in both dams and progeny.

        Breed A females are crossed with breed B sires. The cross - bred females are mated
back to sires of breed A and so on. In this, system the cross -breeds soon come to have about
two -third of their inheritance from the breed of their immediate sire with one - third from the
breed being used.




b. Triple crossing
        In this system three breeds are crossed in a rotational manner. It is also known as
rotational crossing.

        Three breeds are used in this system. The females of crosses are used on a sire of pure
breeds in rotation. The cross-breeds will soon come to have 4/7 of inheritance of the breed of
the immediate sire, 2/7 from the breed of maternal grand -sire and 1/7 of the hereditary material
of the other pure breed.




c. Back crossing
       Back -crossing is mating of a crossbred animal back to one of the pure parent races
which were used to produce it. It is commonly used in genetic studies, but not widely used by
breeders. When one of the parent possesses all or most of the received traits, the back cross
permits a surer analysis of the genetic situation than F2 does.

        A heterozygous individual of the FI when crossed with a number of homozygous
recessive parent race, the off-spring group themselves into a phenotypic ratio of I: I; if, on the
other hand, the individual of the parent race were to be homozygous dominant all the off springs
will be alike.
All being tall, there is no ratio of tall to dwarf

Advantages of cross-breeding
1. It is valuable as a means of desirable characters into a breed in which they have not existed
formerly.
2. It serves a good purpose in evolving a new breed owing to the fact that it disturbs the balance
and brings about recombination in the germplasm to cause variations. Selection can then fix the
favourable variations in the population.
3. It is an extremely handy tool to study the behaviour of characteristics in hereditary
transmission.
4. The cross-bred animals usually exhibit an accelerated growth and vigour or heterosis, which
means the blending of desirable dominant genes from two breeds in the first generation. Such
animals are more thrifty than either of the parents. They grow rapidly, produce more milk, etc
than would be expected from their pedegree. The productive traits usually show the greatest
improvement from cross -breeding.

Disadvantages
1. The breeding merit of cross-bred animals may be slightly reduced because of the
heterozygous nature of their genetic composition, and the fact that all animals transmit only a
sample half of their own genetic materials to their off springs. This may otherwise be explained
that crossing has a tendency to break up established characters and destroy combinations of
characters which have long existed in the strains and behaved in a manner like unit characters
in transmission.

2. Cross-breeding requires maintenance of two or more pure breeds in order to produce the
cross-bred which undoubtedly involved a considerable investment as rapid progress need not
be expected in any line of breeding unless sufficient numbers can be kept to allow for rigid
selection.

3. Species hybridization
       Crossing of individuals from two species is called hybridization. This is the widest
possible out breeding system. It is possible only between related species which might have
descended from common parent stock somewhere back in the evolutionary process. In the
course of time, evolutionary forces might have set them off into distinct species. A well known
example for species hybridization is the mule which is a cross between the jack ass and the
mare. The mule is valued for its ability to work hard under the most adverse conditions. The
mules are generally sterile.

         Similarly, European cattle and American bison when crossed produce sterile males and
fertile females. By back-crossing the females to bison and cattle attempts are being made to
form a new breed of cattle-the cattalo.
        Species crosses are possible only when two species are related closely enough. These
crosses usually result in much heterosis (a phenomenon in which the crosses of unrelated
individuals often result in progeny with increased vigour (much above their parents). However,
the progeny of species crosses have very low or nil fertility.

4. Grading up
         Grading up is the practice of breeding sires of a given breed to non-descript females and
their off-spring for generation after generation. Thus, grading up is a successive use of purebred
bulls of a certain breed of a non-purebred herds. The continued use of good purebred sires for
only a few generations are all that are required to bring the herd to the point at which it has all
the appearance, actions and practical value of pure breeds. The following presentation (table 1.)
shows the rapidity with which purebred sires will Change the genetic composition of the non-
descript one.
                             Table 1. Change in the genetic composition

        Number of                                         Off-springs
        generations
        1st Generation           Percent replaced              Percent non-descript
        2nd    “                             50                             50
         rd
        3      “                             75                             25
        4th    “                            87.5                           12.5
        5th    “                           93.75                           6.25
         th
        6      “                           96.87                           3.13
        7th    “                           98.44                           1.56
        8th    “                           99.22                           0.78

      From the above explanation, we can see that the off springs come closer to a 100%
improved breed, as we go on breeding.

       Grading is a process by which a few purebred sires can rather quickly transform a non
descriptive population into a group of pure breeds. The grading process does not create
anything new but it may transfer the good qualities of an improved breed.

        For a grading up programme, it is advisable to use a breed that I has thrived well under
local condition. Otherwise graded animals may not adapt themselves to the local environment.

Advantages
1. Pure breeds can be obtained just after a few generation (after 7th to 8th generations).
2. The start can be made with a little money in comparison to the purchase of an entire herd of
purebreds.
3. It helps to prove the potentialities of the sire and adds to its market value.
4. It is a good start for new breeders who can slowly change over to pure breed systems.

Limitations of grading
1. Pure breeds are not always better than grade or country animals
for the use to be made of them.
2. Pure breed stocks which give good results in one set of environmental conditions do not
always give favourable results in some different environmental set up. The pure breed dairy
cattle from temperate zones often degenerate when used in tropical areas. Moreover, their off
springs fail to show vigour and constitution for high reproduction. To make grading successful
the pure breed must have the ability to perfonn under the environmental set up where their
offspring is going to perform.

VII. Improvement of Dairy Cattle in India
        The dairy fanning business in many tropical and subtropical countries are characterized
by large number of cattle and low yield of milk. For example, India possesses over 230 million
heads of cattle and buffaloes, which comes to more than one-fifth of the total world population of
cattle and buffaloes. The average annual production of an Indian cow is only 173 kg as against
an average yield per milking cow of 3,710 kg in Denmark, 3,250 kg in Switzerland and 3280 kg
in the U.S.A.

        Twenty six breeds of cattle and seven breeds of buffaloes have been recognised at
present in India. However, only a small proportion of the cattle and buffaloes belong to these
purebred breeds. The vast majority (more than 75%) are intermixed and do not belong to any
specific breed. They are classed as nondescript.

         Cattle remain the draught animals in many of these regions. As a result selection over
the past many centuries has been to meet the requirements of draught and agriculture.
Selection pressure was applied for better capacity and fitness. This has resulted in producing
excellent draught animals. Unfortunately, milk production and draught capacity are traits which
are genetically negatively correlated. When milk yield capacity goes up, draught capacity goes
down and vice versa. As a result attempts to develop and improve some of the dual purpose
breeds which are useful for both milk and work, could not progress very far. We could have only
a compromise in dual purpose breeds with medium milk production and medium work capacity.
If further genetic improvement of either of the two traits is attempted, a set back with respect to
the other should be expected.

       In India, at present 94.3% of the milch cows yield less than one kg. milk per day. Only
0.5% yield more than 2 kg per day. Buffaloes are better milk producers. About 18 -20% of the
milch buffaloes yield more than 2 kg per day and only 19% yield less than one kg per day. The
reasons for such a low level of production are listed below.

I. Acute shortage of feed and fodders.
2. Excess cattle numbers.
3. Poor genetic potential for milk production.
4. The smallness of land holdings and consequently small dairy units make them economically
unviable. It also acts against introduction of advanced techniques.
5. Adverse climatic conditions of the tropics.
6. Poor grazing and environmental factors.
7. Inadequate marketing facilities for the products.

        The diversity of the breeding stock and the variation available in economic traits of cattle
and buffaloes in the country offer greater challenge and scope for their improvement for the
animal breeder. At the same time, the task of improving the genetic make up of a large number
of extremely diverse, non-descript low producers is a colossal one. Anyone system of breeding
can not be applied uniformly to all the animals in all the areas.

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