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Executive Summary
Livestock animals meet a variety of human needs. They are
important sources of transport, draft power, fiber, hides, fertil-
izer, fuel, and nutritional protein in the form of meat, milk,
eggs, and processed products, such as cheese. More than half of all
protein consumed by humans comes from livestock and fish, which
are a more complete source of essential amino acids than are plants.
As nations struggle to improve nutrition and to feed their growing
populations, demands for the food, fiber, and other products derived
from livestock will increase.
As with crop plants, the purpose of livestock genetic resource
management is to maintain a reservoir of potentially useful genetic
variation culled from the multitude of livestock breeds and varieties
within species. Even though there is little danger that the major
domestic animal species, such as Bos Taurus (cattle) or Callus domesticus
(chickens), will become extinct, genes from preserved livestock germplasm
can be used for developing new types and breeds, adapting existing
types and breeds to new conditions, or meeting changing consumer
preferences or production requirements.
The application of the science of genetics in this century to breed-
ing and improvement has substantially increased agricultural pro-
duction, but it could have deleterious effects in the future. Basic to
developing new and more productive animals with better nutritional
qualities has been the availability of diverse breeding populations
that possess genes useful for livestock improvement. As new breeds
develop and spread, however, they may displace indigenous breed
1
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2 / Livestock
ing populations. Furthermore, as the efficiency of selection within
commercial breeds increases, the capacity within a breed for genetic
change could become limited. Preserving society's capacity to im-
prove and develop modern livestock requires that actions are taken
to prevent the loss of potentially valuable genetic resources. Because
future needs cannot be reliably predicted, a broad array of genetic
diversity must be conserved.
T\X!O VIEWS ON LIVESTOCK CONSERVATION
-
Although a consensus within the livestock community exists on
the need to develop national and international efforts to preserve and
manage livestock genetic resources, the approaches to conservation
differ widely. They hinge on differences in opinion about the impor-
tance of traditional livestock breeds, including indigenous breeds, for
long-term genetic improvement programs. In general terms, these
approaches can be divided into two broad categories: utilization and
preservation.
The utilizationist's primary concern is the immediate usefulness
of available genetic resources to improve livestock populations. De-
scendants of animals with documentable, unique biological charac-
teristics are to be maintained for future use. The loss of breeds as
distinct identities is not generally a concern, as long as the genes that
make these breeds potentially useful are retained in commercial stocks.
The preservationist's primary objective is long-term conservation
of genetic resources for future use. This view emphasizes the value
of preserving the widest possible spectrum of genetic diversity to be
prepared for unpredictable changes or future needs. The greatest
possible number of breeds are to be preserved as purebreds.
Differences between the preservationist and utilizationist views
largely pertain to perspective and emphasis, but they strongly influ-
ence the practices that are favored for managing genetic resources.
The committee bases its conclusions and recommendations on the
common goal held by proponents of both views the goal of sus-
tained improvement of livestock for use by an expanding global popu-
lation. Setting national or global priorities for sustained livestock
improvement will depend on a variety of factors, including available
funding and technical expertise, national and international needs, and
genetic similarity among available breeds and populations. How-
ever, the committee believes that at a minimum, conservation should
focus on breeds that are (1) of potential economic value, or (2) are
both endangered and represent types with unique biological charac-
teristics.
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Executive Summary / 3
What scientists have come to understand thus far about livestock
is impressive. This basic knowledge has been swiftly carried forward
by application. With such rapid advances in science and application,
it is imperative that policymakers and researchers seize the opportu-
nity now to put into place priorities for the improved preservation
and management of livestock genetic resources.
GENETIC DIVERSITY OF LIVESTOCK
Genetic diversity within a livestock species is reflected in the
range of types and breeds that exist and in the variation present
within each. Examples of types include milk or beef cattle, milk,
meat, or wool sheep, and layer hens or broiler chickens. In dairy
cattle, examples of breeds include Holstein-Friesian, Jersey, and the
Swedish Red-and-White.
For growth and maternal traits in cattle, Cundiff et al. (1986) has
shown that differences among breeds substantially exceed those within
breeds. This conclusion can probably be extended to other traits and
species, and it suggests that genetic variation among breeds is a ma-
jor component of the readily accessible livestock diversity. Thus losses
of unique types and breeds compromise access to their unique genes
and gene combinations.
For example, in sheep raised for meat, intensification of produc-
tion in the early 1970s led to a desire to increase lambing rates in
commercial stock. Selection within existing North American breeds
could increase the lambing rate by perhaps .02 lambs per ewe annu-
ally. Thus achievement of 0.50 in lambs per year (from 1.50 to 2.00
lambs/ewe/year) would have taken 25 years. Yet through utilization
of the prolific Finnish Landrace, a breed that was, at the time, little
more than a novel indigenous type of Northern Europe with a mean
lambing rate in excess of 2.5, a single generation of crossing to cur-
rent commercial breeds led to a ewe with a lambing rate of about 2.0.
This example illustrates the point that within-breed selection can lead
to great genetic change, but only over a long period of intense selec-
tion. The presence of a breed with the desired characteristics already
in place and with the controlling genes already at high frequency
greatly enhances the efficiency of the improvement process.
At times, however, within-breed selection will be required to go
beyond the limits of existing breeds. The genetic variation within
commercial stocks is the ultimate raw material that allows continued
improvements or, if necessary, redirection of selection to achieve new
results. The recombination and concentration of favorable genes within
major commercial stocks under intensive selection have allowed de
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4 / Livestock
velopment of animals with productive capacities that greatly exceed
those of their ancestors. Likewise, the store of genetic diversity within
commercial breeds has permitted relatively prompt responses to changes
in societal demands. The change from the relatively fat pigs of the
1950s to the extremely lean pigs of today was achieved largely through
within-breed selection.
Historically, the preservation of genetic diversity within commer-
cial breeds has not been an issue. Accurate identification of superior
individuals and their intensive propagation have justifiably received
much greater emphasis in order to increase production (more milk
from a cow, for example). It can be argued that if genetic diversity
were declining, the selection of stocks for commercially desired traits
would be less productive for developing improved breeds. However,
a decreasing rate of response to selection cannot be documented. Yet
technological advances in animal breeding and reproductive control
have the potential to change this situation. Embryo transfer and
cloning, molecular aids to selection, and greater control of reproduc-
tive processes can produce rapid and considerable increases in both
the accuracy of selection and in the ability to propagate selected indi-
viduals. Through the use of follicle maturation techniques, in vitro
fertilization, and embryo cloning, a pair of parents could produce
hundreds, or even thousands, of progeny. Given this prospect, con-
sideration of the maintenance of genetic diversity must become part
of livestock improvement programs.
Origins of Traditional Breeds
Hoofed animals, specifically cattle, goats, pigs, and sheep, first
began to be domesticated about 11,000 years ago. They quickly be-
came essential to the establishment and spread of agriculture. A
wide array of subpopulations evolved through adaptation to differ-
ent environments, as humans migrated, over several thousand years
and through breeding efforts during the past 200 years. These sub-
populations are generally recognized as breeds, that is, groups of
individuals that are similar in their appearance and characteristics.
Their genetic diversity has been shaped by the need to adapt to tem-
perature extremes, humidity, variations in quality and availability of
feed supplies, diseases and parasites, and other factors that are re-
gionally and globally divergent. They represent easily recognizable
genetic resources that can serve as a convenient and reliable source
of genes associated with particular physiological or morphological
characteristics.
For example, Criollo cattle in South America are descended from
Iberian stock brought to the Americas during the 1500s. Over the
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Executive Summary / 5
past 500 years they have developed traits, through natural selection,
that enable them to live on poor nutritional levels and to withstand
climatic extremes. Genetic diversity has allowed for their survival,
and they are now a source of genes that may contribute to adapting
other breeds for production in comparable environments around the
world.
One of the challenges in conserving genetic resources is to pre-
vent excessive losses of unique, adapted breeds. They need to be
maintained, and their potential contribution to future commercial stocks
should be carefully assessed.
Displacement of Traditional Breeds
The traditional indigenous breeds, particularly in developing coun-
tries, are generally considered to be at greatest risk of genetic loss. In
the tropics, temperate breeds usually cannot be introduced as pure-
bred animals without also introducing high levels of feeding, special
management, investments, and risks. Small farmers often cannot af-
ford the cost of the high-maintenance breeds that are being intro-
duced. However, these breeds are commonly crossbred with local
animals to combine adaptation and disease resistance with higher
production. Although the traditional indigenous breeds are needed
initially to produce crossbreeds, and perhaps over the longer term to
create a stable self-perpetuating subpopulation, their critical role in
maintaining self-perpetuating breeding programs is often not recog-
nized. Farmers may be reluctant to keep the indigenous breeds if
they are less profitable than crossbreeds. As a result, indigenous
breeds lose their genetic identity or disappear.
Although the extent and usefulness of genetic variation among
most traditional breeds have not yet been fully characterized, the
differentiation clearly reflects a wealth of genetic diversity within the
species diversity that permits further selection and improvement.
In particular, these populations hold genetic combinations that may
prove valuable in meeting future environmental, production, or mar-
keting conditions.
In many temperate regions, a number of local breeds have al-
ready been replaced by high-performance and more economically vi-
able breeds. For example, in Great Britain, the English Longhorn was
the dominant cattle breed during the nineteenth century. It was prized
for its size and fat, because draft work and tallow for candles were
the important products of the time.
Beginning only about 200 years ago, when the horse became the
preferred draft animal, the enclosure of common land made controlled
breeding possible (Mason, 1984~. Cattle feeding practices also im
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6 / Livestock
proved (Mason, 1984~. By the turn of the century, selection for milk
and beef production became paramount and the Longhorn's position
gave way to the Shorthorn, a dual-purpose, milk and beef breed. By
the mid-twentieth century, the Holstein-Friesian, a specialized dairy
breed, was on the rise in the United Kingdom, and large continental
breeds, such as the Charolais, were being used as sire lines for beef
production. The flexibility to change genotype relatively quickly to
meet changing market requirements results from the genetic varia-
tion between breeds. This same flexibility will likely be required
under future, unforeseen production conditions.
The Impact of Technology
Recent biotechnological advances can further alter genetic struc-
ture and limit the diversity of livestock species. Cryopreservation of
semen and embryos (storage typically in liquid nitrogen at a tempera-
ture of -196°C) is now feasible for many livestock species. Germplasm
can be stored indefinitely and shipped worldwide. Health concerns,
traditionally a barrier to international transport of livestock, may soon
be resolved by special handling techniques for embryos that provide
better control against the spread of pathogenic organisms. The inter-
national transport of germplasm can be expected to increase. Con-
currently, technology advances for storing and transporting semen
and embryos have allowed the trend toward widespread use of germ-
plasm from a small number of individuals, which could cause overall
genetic diversity to decline.
Regardless of geographic location, when production and market-
ing systems become more uniform or when the influx of foreign
germplasm of one breed is allowed to dominate the population, the
danger of narrowing the genetic base of livestock species exists. The
application of new technology for germplasm propagation and dis-
semination may contribute to the erosion of diversity. Unique germplasm
is threatened by replacement of breeds with more productive or popular
stocks, dilution of breeds through crossbreeding programs, and de-
creased diversity within highly selected breeds or lines that have a
small number of breeding individuals. The committee believes that
it is now time, scientifically and socially, to address these concerns in
the design of programs for livestock improvement.
LIVESTOCK PRODUCTION SYSTEMS
Production and management systems for domestic livestock can
be broadly classified as either intensive or extensive. Intensive sys
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Executive Summary / 7
A_
A_
_ _
_
A young female commune worker in the People's Republic of China collects
eggs from chickens kept in cages, a common intensive production approach
used for poultry. Credit: Dean Conger, O1992 National Geographic Society.
tems were developed in the latter half of the twentieth century and
involve high levels of inputs, such as supplemental feed and disease
prevention efforts, and require more capital investment, such as housing
construction and equipment. Chickens, for example, are now com-
monly raised in confined, environmentally controlled housing with
sophisticated disease control programs. This type of system is more
frequently found in developed countries, which have the capital to
invest, plentiful grain supplies for animal feed, and supportive tech-
nologies such as veterinary care and modern production facilities.
The stocks of chickens, dairy cattle, pigs, and turkeys that now
predominate in developed countries have been selected for high pro-
duction under intensive management and optimal environmental con-
ditions. The genetic base of these specialized stocks may become
more narrow because of intensification of selection and smaller effec-
tive population sizes (the number of reproducing individuals in a
population). Examples of specialized stocks are Leghorn chickens,
which are superior for egg production, and the familiar black and
white Holstein-Friesian cattle, which dominate other dairy cattle breeds
because of higher milk production.
The term extensive describes the more traditional systems used to
raise livestock. Fewer purchased inputs, such as high-quality feed or
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8 / Livestock
pharmaceuticals, are provided. For ruminants, this approach involves
maintaining animals, such as cattle, goats, and sheep, under range
conditions. Backyard poultry and swine production is another ex-
ample of extensive systems. Nutritional supplementation and veteri-
nary care are minimal or nonexistent.
In extensive systems, animals are generally less protected from a
variety of environmental and nutritional stresses, and they can be-
come adapted to local conditions over long periods of time (several
generations). The N'Dama cattle of West Africa, for example, are
genetically tolerant of the effects of trypanosome infection and, thus,
can survive in an area that is inhospitable to susceptible breeds. In
Africa, about 30 percent of the 147 million cattle in countries inhab-
ited by the tsetse fly, which transmits trypanosomiasis, are exposed
to the disease. The disease can cause poor growth, weight loss, low
milk yield, reduced capacity for work, infertility, abortion, and early
death. Annual losses in the value of meat production alone are esti-
mated at $5 billion. Additional costs come from losses in milk yields,
tractive power, waste products that provide natural fuel and fertil-
izer, and secondary products, such as hides (International Laboratory
for Research on Animal Diseases, 1991~.
Animals in extensive production systems, like this flock of sheep in Tunisia,
usually forage and water on open pasture. Credit: Food and Agriculture
Organization of the United Nations.
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Executive Summary / 9
WHY CONSERVE THE GENETIC DIVERSITY OF LIVESTOCK?
Extinction is not a concern for the major domestic species, which
benefit from society's protective custody. Large total population sizes
are maintained to ensure adequate product supplies, and the species'
basic needs are usually met. Total population sizes are generally in
the hundreds of millions, even though the effective population size
may be much smaller.
The compelling need for conserving domestic species is to pre-
vent the loss of the many differentiated populations that, because of
geographic or reproductive isolation, have evolved distinct charac-
teristics and now occupy different environmental niches. A further
need exists to guard against depleting diversity due to current breed-
ing technologies, worldwide movement of germplasm, the prolifera-
tion of highly selected industrialized breeds, and commercial stocks
founded on a relatively small number of breeding individuals. The
range of genetic diversity in livestock species must be saved as a
foundation for future improvements and adjustments to changing
production conditions.
Because the ultimate effects of diminished genetic diversity are
hard to estimate, given the unpredictability of future needs, the con-
servation of livestock genetic diversity can best be considered as a
form of insurance. Preserved stocks will possess potential economic,
scientific, and sociocultural benefits.
Economic Benefits
Genetic variation provides the foundation to continue improve-
ments in production efficiency and to accommodate, relatively rap-
idly, unpredicted changes in the methods for producing animals and
marketing their products, or in the demand for animal products. An
example of the need to respond to changing demands is seen in the
pork industry where several decades ago animals that possessed large
amounts of fat for lard were desired. With the advent of consumer
concerns about animal fats, and the ready availability of vegetable
shortenings, the demand for lard declined. Consequently, breeders
produced the leaner, meat-producing animals prevalent today.
Scientific Benefits
Studies of genetic variation and gene variants provide insight
into physiological and biochemical functions, gene structure and con-
trol, and evolutionary processes in animals. Miniature pigs (a geno-
type commonly used in studies of growth, obesity, and diabetes) il
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10 / Livestock
lustrate the use of a domestic stock to further scientific investiga-
tions. Such studies are beneficial to both animal and human health.
Sociocultural Benefits
Genetic diversity may be of social or cultural value. Some animals
are used for recreation, and animal breed exhibits and fairs are attrac-
tions for many people. Genuine cultural benefits can be realized through
the use of animals to visually chart important historical developments-
certain breeds are living evidence of a nation's agricultural heritage. In
Hungary and France, for example, traditional indigenous breeds are
maintained in national park settings and serve as tourist attractions.
Traditional livestock breeds are essential components of living his-
torical farms in Europe and North America. In addition, specific
livestock breeds characterize the way of life and provide specific products
for many villages and regions around the world.
TECHNOLOGIES FOR CONSERVING AND USING GERMPLASM
Recent technological developments may, in some instances, have
a negative impact on genetic diversity by reducing the number of
parents required to propagate a population. However, they also open
important avenues for expanding the scope and assessing the poten-
tial value of conservation efforts. Improved reproductive technolo-
gies enhance the feasibility of preserving germplasm through better
reproduction rates and disease control. Molecular technologies pro-
~ride more understanding and control at the level of the gene, and
should vastly improve opportunities to use preserved stocks.
Molecular Technologies
New molecular genetic technologies will improve the use of pre-
served stocks and aid in assessing genetic distance and variation.
For example, individual animals could be selected for breeding and
preservation based on specific knowledge of their genotypes. Mo-
lecular studies may provide greatly enhanced understanding of the
genetic basis of important livestock production traits. These tech-
nologies also promise the capacity to move routinely important genes
between unrelated animal species.
Characterization of Genomes
Methods to characterize the genomes of individual animals and
the gene pools of breeds are becoming a reality. A variety of tech
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Executive Summary / 11
niques is available to quantify genetic variation at the levels of the
gene product and of the gene itself. Numerous studies have exam-
ined variation in the protein products of the genes, but as molecular
technologies become more sophisticated, the focus is shifting to the
genes and the DNA (deoxyribonucleic acid) to quantify differences
among individuals, breeds, and species. Genetic distances, indexes
of the relative genetic differences between two or more breeds, can
be estimated. This information can be used to aid decisions regard-
ing preservation that are based on the genetic uniqueness of a germ-
plasm source.
Gene Transfer and Mapping Technologies
The expansion of research on the effects of specific genes, and on
their transfer between individuals of the same or different species,
has major implications for the potential value of preserved germplasm.
It should be possible to screen preserved stocks and, if desired, to
extract and use a beneficial gene or genes that may be located in an
otherwise undesirable background. For example, the International
Livestock Center for Africa, in Ethiopia, and the International Labo-
ratory for Research on Animal Diseases, in Kenya, are cooperatively
conducting research to identify the genetic basis of tolerance to try-
panosome infection. This knowledge (and perhaps the genes them-
selves) may expand the tolerance to trypanosomiasis of livestock across
breeds and even species.
Efforts to map livestock genomes are progressing. Advances in
sequencing and mapping techniques that emerge during this effort
will enhance, and be enhanced by, identification and use of human
genes.
Genomic Libraries
Today's technology permits the formation of genomic libraries
theoretically containing the full set of genes from any given indi-
vidual. However, a tremendous amount of research must still be
done to identify genes of importance. Regeneration of living animals
from DNA stores in genomic libraries is not yet possible, and ge-
nomic libraries should only be considered as an adjunct means of
germplasm storage at this time. Their potential value as a preserva-
tion tool, however, can be likened to a form of insurance. It is antici-
pated that methods will improve for isolating and manipulating spe-
cific DNA segments.
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12 / Livestock
Animal Reproduction Technologies
Animal reproduction technologies include multiple ovulation, in
vitro fertilization, embryo transfer, embryo splitting, cloning, sexing,
and cryopreservation. The cryopreservation of gametes and embryos
is a well-established technology in livestock production, although suc-
cessful application to a wider array of livestock species and to oo-
cytes and embryos requires more research and development. Nota-
bly, methods to cryopreserve pig embryos have been unreliable. Although
widespread use of these technologies can narrow the breeding popu-
lation and thereby have negative impacts on genetic diversity, these
technologies can also, if properly used, become tools for support of
genetic resource management.
An important development in embryo research has been the use
of hormones that induce multiple ovulations in a donor female and
lead to a greater number of embryos. This capacity is especially
important in species that normally produce only one offspring per
pregnancy. Further, embryos can be cloned to produce genetically
identical animals, providing much greater flexibility in distribution
and research efforts.
One of the main limitations to the movement and use of genetic
resources has been concern about the health status of the germplasm.
If, in the course of importing livestock, exotic diseases are inadver-
tently introduced into a region, the effects on indigenous stocks could
be devastating. Most nations have not been willing to take the risks
involved in importing livestock. However, methods for the screen-
ing, diagnosis, and control of diseases are improving, and new em-
bryo-washing techniques offer promise for eliminating disease agents.
The international movement of animal breeding stock as frozen se-
men and embryos is thus becoming more feasible.
METHODS OF PRESERVING ANIMAL GERMPLASM
Three basic approaches can be identified for preserving genetic
diversity: maintaining living herds or flocks, cryopreserving gametes
or embryos, and establishing genomic libraries. The vast majority of
livestock genetic resources will continue to be maintained in living
herds and flocks, many of which are privately owned. If the size of
the breeding population is sufficiently large and the population is
not decreasing in number, directed conservation efforts will not be
required. Periodic inventories of animal populations can provide
early warnings of any changing patterns in production or use that
may alter the diversity within breeds. A major advantage of preserv
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Executive Summary /13
ing live herds and flocks is the opportunity for selection, thereby
allowing the breed to adapt to shifting environmental conditions.
Frozen storage of gametes and embryos offers a cost-effective method
to preserve the genetic material of a breed for an indefinite period of
time. Collection and freezing of semen is relatively simple and, if
samples are collected from a sufficient number of males, allows the
preservation of essentially all the genetic variation in a stock. The
costs of collection are not excessive, although in remote areas where
accessibility to equipment and facilities may be problematic, they can
be higher. The cost of maintaining the samples in frozen storage is
low. Methods for collecting, handling, and freezing embryos, although
more complex than those for semen, also offer efficient means of
preservation. Embryo storage has not been used for conservation, in
part because of the cost of sampling, but research on collecting and
handling oocytes and embryos is advancing rapidly. Cryopreservation
can complement efforts to preserve live populations, and it should be
used as a safeguard when population numbers are dangerously low
or when certain breeds or lines are likely to be replaced with other
populations.
As noted earlier, genomic libraries are of little use for breed pres-
ervation. As technologies develop, however, they may provide an
important mechanism not only for conserving diversity, but also for
accessing particular genes. Their value will be enhanced with con-
tinuing advances in molecular genetics research.
Criteria and priorities must be established to identify which ge-
netic resources merit conservation. Considerable attention has been
given to determining the basis for classifying a breed as endangered,
and guidelines for various species are available to aid in evaluating
preservation needs (Maijala et al., 1984~. However, the status of each
breed must be evaluated on a case-by-case basis. In general, an en-
dangered breed is defined as having a small and decreasing number
of breeding individuals. Unfortunately, in developing countries, fre-
quently little or no information is available on certain breeds, and
information cannot be quickly gathered. At times, extemporaneous
judgments must be made about which individuals constitute a breed-
ing population.
Once a decision is made to preserve a breed, a sampling strategy
must be developed. Factors such as geographic distribution and popu-
lation structure, if known, should be taken into consideration. A
stratified system of sampling (that is, identifying breeds and taking
samples of unrelated individuals and at random) will in most situa-
tions be appropriate.
The effective preservation and management of livestock genetic
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14 / Livestock
resources will require organization and accessibility of basic informa-
tion on animal breeds in a data base. Although some descriptive and
analytic information exists for many livestock breeds, it still may be
insufficient for making management decisions. Studies to inventory,
characterize, and compare livestock populations are badly needed,
particularly in developing countries. The cataloging of information
so it can be readily retrieved will be critical. Information accruing
from research on gene mapping, gene transfer, and related technolo-
gies must also be cataloged in an accessible format.
EFFORTS TO IMPLEMENT LIVESTOCK CONSERVATION
The issues surrounding the conservation of animal genetic re-
sources have been discussed and debated for more than 30 years.
Conclusions generally have been similar:
· Diversity in livestock breeds is increasingly at risk,
· Valid reasons exist to conserve diversity, and
· Organized preservation and management activities are highly
desirable.
Nevertheless, active programs to inventory and preserve genetic
diversity are the exception rather than the rule. This situation ap-
pears to be changing as more developed and several developing countries
implement preservation and management programs for animal ge-
netic resources.
The lead on discussions of genetic resource management has largely
been taken by the Food and Agriculture Organization (FAO) of the
United Nations, with support from the United Nations Environment
Program (UNEP). The FAO has contributed through its comprehen-
sive publications on characterization and management techniques of
animal genetic resources. It has also recognized the need for collat-
ing information contained in central data bases, and has supported
studies to determine how best to establish and organize such data
bases. In 1989, the Commission on Plant Genetic Resources of the FAO
voted to address conservation of animal genetic resources in addition to
plants, thereby demonstrating its recognition of the importance of
livestock genetic resources in global agricultural production.
In 1992, FAO announced the initiation of a program to conserve
and develop the livestock and poultry genetic resources of develop-
ing nations (Henson, 1992; Ruane, 1992~. Its five elements are a glo-
bal inventory, breed preservation, indigenous breed development and
conservation, gene technologies, and a legal and international frame-
work. The Global Data Bank for Domestic Livestock, based in Rome,
Hi,
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Executive Summary / 15
Italy, covers all areas of the world with the exception of Europe, but
including the Commonwealth of Independent States (the former So-
viet Union). This data base will document arid characterize the dif-
ferent populations of domestic livestock.
The loss of local minor breeds has been a concern in Europe for
many decades. The European Association for Animal Production (EAAP),
based in Italy, formed a group to coordinate activities relating to
livestock resources of Europe. National conservation programs have
been established both in Europe and In several developing countries.
The FAO and EAAP have promoted establishment of a regional data
base for Europe. The Animal Genetic Data Bank at the Hanover
School of Veterinary Medicine in Germany records census data on
populations of breeds arid genetic characterization data. The data
bank will be valuable to educational institutions, governments, com-
mercial interests, and others who are concerned with the conserva-
tion of animal genetic resources.
RECOMMENDATIONS
Livestock genetic diversity is an essential component of livestock
improvement programs, especially to meet the future needs of hu-
man society. There is a paucity of quantitative evidence to support
arguments for He need to conserve livestock genetic resources. However,
when examining the use made of landraces in plant improvement in
both developed and developing nations, the committee concluded
that it is prudent to preserve unique sources of germplasm in ani-
mals as well.
Ensuring that livestock resources will be preserved and properly
used will require expansion and coordination of existing efforts and
implementation of new ones. Technologies that emerge from scien-
tific research will enhance the present capacities to preserve and use
animal genetic diversity. Ultimately, conservation of livestock ge-
netic resources will require cooperation at the national and global
levels. The following are the committee's major recommendations
for addressing the management and use of livestock genetic resources.
Additional recommendations and further detail are presented in the
main text.
Expanded Programs ant! Activities
Mechanisms must be put in place to ensure that genetic diversity of the
major livestock species is maintained to support improvements in produc-
tion efficiency and to Accommodate future changes in selection goals.
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16 / Livestock
The issues surrounding the need to conserve livestock resources
have been discussed for many years in a variety of forums. For
example, FAO forums have provided a wealth of guidelines for es-
tablishing programs, and the FAO and UNEP have worked together
to supply training and to organize regional meetings on animal ge-
netic resources. Additional activities have been ongoing in Africa,
Asia, Europe, and Latin America. All of these efforts recognize the
urgent need to integrate conservation and livestock improvement ef-
forts. If action is not taken soon, potentially valuable livestock ge-
netic resources could be lost.
Documentation of Breeds
Increased efforts are needed to inventory and characterize unique and
endangered populations and breeds, particularly in developing countries.
Decisions about needs and priorities in livestock conservation pro-
grams must be based on knowledge of the animal populations. For
populations found in developing regions, the need for documenta-
tion is particularly acute, because industrialization and the importa-
tion of improved breeds can threaten indigenous breeds. An essen-
tial component of this process is establishing national and international
data bases that maintain information in a readily accessible form.
The Animal Genetic Data Bank at the Hanover School of Veterinary
Medicine and FAO's world inventory of native livestock breeds and
strains constitute a good beginning, but much greater effort is needed
to collect information, particularly from developing countries.
Increased Cooperation
aged.
Private efforts to preserve animals in breeding herds should be encour
Private farm parks, such as those associated with the Rare Breeds
Survival Trust in England, have proved successful in preserving se-
lected rare or historic breeds. In some cases, governments have sub-
sidized or otherwise assisted farmers who elected to maintain ani-
mals of particular breeds. In Canada, for example, farmers in the
Province of Quebec are paid for rearing purebred Canadienne cattle.
Cooperation also could take the form of exchanging information about
the breeds preserved or of providing technical assistance on breeding
programs to control inbreeding or ensure breed purity.
Although the many herds and flocks held by private individuals
and groups may not originally have been assembled for conservation
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Executive Summary / 17
motives, these populations can supplement public activities. The ef-
forts of these groups enable a broader diversity of breeds and popu-
lations to be preserved than would otherwise be possible with na-
tional resources that are frequently limited. Responsible private efforts
to preserve livestock germplasm should be encouraged and offered
public support.
Research and Technology Development
Research on technologies that could benefit preservation and use of
animal genetic resources should be continued and expanded.
Research in new technologies, such as genome mapping and gene
transfer, is moving at a rapid pace. Future breakthroughs are likely
to have significant effects on the efficiency of animal production and
on the ability and need to preserve germplasm. Major research ef-
forts are under way on the human genome, and complementary work
is progressing on the genomes of cattle, pigs, and sheep. Preliminary
results suggest that much of the genomic information from one spe-
cies will be applicable to others. To maximize the efficiency of basic
and applied research, geneticists working in different areas and on
different species must take the initiative to cooperate and share infor-
mation. A number of research areas have potential to enhance the
preservation, management, and use of animal genetic resources.
Cryopreservation as a Supplement to Breeding Populations
The preservation and management of endangered and unique popula-
tions as breeding herds orflocks should be supplemented by cryopreservation
of their germplasm.
Cryopreservation of semen and embryos complements preserva-
tion of live populations and provides a safeguard when population
numbers are dangerously low or when breeds or lines are likely to be
replaced or lost. It offers the potential to store large numbers of
genotypes for indefinite periods of time. In general, the costs of
collecting and processing samples for cryopreservation are not exces-
sive for domestic animals, particularly in regard to semen.
At present, semen from the major livestock species can be
cryopreserved, but the process is only reliable enough to be routine
and commercial for species such as cattle and, increasingly, sheep.
For pigs, goats, horses, and poultry, cryopreservation methods, al-
though available, need further refinement. The effectiveness of
cryopreservation for preserving species and breeds of minor live
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18 / Livestock
stock is less well established. With semen storage, it is not possible
to derive purebreeding stock from stored germplasm unless suitable
female recipients are available. However, the most common future
use of cryopreserved germplasm is expected to involve crosses with
commercial populations to introduce new genetic traits and develop
new breeds. Frozen semen is ideal for such use.
Mouse embryos were reported to be successfully cryopreserved,
thawed, and implanted in 1972. Since then, the procedures have
become routine in several mammalian species, including cattle, sheep,
rabbits, and mice. Notably, efforts to cryopreserve pig embryos have
been unsuccessful. Cryopreservation of male and female embryos
preserves the entire genome of a breed and is particularly appropri-
ate when regeneration of purebred animals is desired.
National Initiatives
National programs for preserving, managing, and using livestock ge-
netic resources must be established in developed and developing countries
and suited to different needs.
Before global efforts can be effective, conservation of animal ge-
netic resources must be a national initiative. Given the substantial
differences in needs and appropriate approaches in individual coun-
tries, the organization of national conservation programs will vary
widely. It is important that private and public interests within each
country cooperate in developing a strategy to ensure an effective,
coordinated national program. The support of a strong network of
national programs is essential to the success of international conser-
vation efforts.
Mechanisms for providing bilateral and multilateral support to enable
developing nations to preserve, manage, and use their livestock genetic re-
sources must be developed.
Multilateral and bilateral aid programs will be required in many
cases to help establish national preservation and utilization efforts in
developing countries. Technical expertise from the developed coun-
tries should also be readily available. Conservation of genetic diver-
sity is a global concern, and given the greater threat to uncharacterized,
unimproved livestock populations in developing countries, support
from conservation programs by developed nations is essential. Ulti-
mately, livestock production and improvement programs of both de-
veloped and developing countries will benefit from international support
and assistance and from enhanced international movement of germplasm
resources.
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Executive Summary / 19
A Global Organization
A global mechanism should be established to provide leadership and
support to nations to ensure the adequate conservation of livestock genetic
resources.
International leadership is needed to coordinate and facilitate na-
tional and regional efforts, and to foster cooperation among national
efforts. An organization with leadership responsibilities could as-
semble experienced specialists to develop priorities and guidelines
for global cooperation. This organization must have the confidence
of financial donors in its ability to succeed, scientific capability, ad-
ministrative expertise, and a consultative mechanism.
The committee examined three potential options for achieving
the necessary global leadership and coordination:
· Establishing an institute within the Consultative Group on In-
ternational Agricultural Research (CGIAR);
· Expanding the efforts of the FAO; and
· Expanding support to an existing institution, such as the World
Conservation Union (IUCN), formerly the International Union for
Conservation of Nature and Natural Resources.
Organizing a new program within the CGIAR or expanding the
existing International Board for Plant Genetic Resources (IBPGR) would
require new financial resources and considerable study. The FAO's
work in this area spans more than 4 decades, and it has an experi-
enced administration in place that could manage a conservation pro-
gram. However, it has certain limitations. For example, although
FAO has a clear mandate to fully develop many of the actions recom-
mended by its advisory panels, its funding is inadequate.
Most conservation-related organizations are not structured to deal
with agricultural germplasm preservation. Some reorientation of pro-
grams, funding, philosophy, and purpose may be required. An orga-
nization that might undertake responsibility for animal genetic re-
sources is IUCN, which has been involved in conservation activities
for more than 40 years. It has experience in developing data bases
for supporting conservation activities with wildlife, monitoring natu-
ral areas, and fostering international cooperation for conservation (Office
of Technology Assessment, 1987~. Expansion of its mandate would
be needed to include livestock genetic resources, and philosophical
conflicts between the needs of agriculture and the organization's en-
vironmental priorities are likely.
Given the need to establish global leadership in guiding, coordi-
nating, promoting, and instituting animal genetic resource conserva
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20 / Livestock
lion efforts, the committee considers the FAO to be an appropriate
institution for these efforts. However, FAO should call on the exper-
tise of other national and international institutions to achieve its goals.
In conclusion, a broad base of genetic diversity in domestic ani-
mal species must be maintained to provide flexibility to improve livestock
for today's production conditions and to meet unforeseen future pro-
cluction requirements. Technological advances in identifying and propa-
gating superior types may allow for substantial losses in genetic di-
versity. These situations suggest that designers of livestock improvement
programs must begin conscientiously to consider their potential im-
pact on genetic diversity.
Representative terms from entire chapter:
genetic diversity
