Domestic Animal Diversity

Industrial livestock production and also increasingly livestock production in mixed crop-livestock systems use a very limited range of animal breeds. This has already led to the extinction of some local livestock breeds and to the genetic erosion of others. Specific genetically determined capacities in local breeds to cope with the climatic, nutritional and disease challenge may already have been lost.

Livestock Diversity Contribution from Diversity Loss of Agricultural Diversity: Pressure State Response Conservation of Livestock Diversity References and Further Reading

Domestic Animal Diversity covers the spectrum of genetic differences within each breed, and across all breeds within each domestic animal species, together with the species differences. This variety is available for the sustainable intensification of food and agriculture production.

Despite agricultural advances, an estimated 826 million people, or about 13% of the world’s population, still go hungry. The development of high-performing livestock and poultry breeds has greatly contributed to the increase of food production, especially in temperate climates. These advances in technology are increasingly being adopted in tropical regions, but their indiscriminate export into tropical countries has at times ended in failure. The animals cannot stand the heat, they need optimal inputs and more easily develop diseases. To overcome these weaknesses, the ongoing approach is the widespread promotion of crossbreeding high-yielding breeds with hardy and well adapted local animals. The price of this and other developments is high: local breeds are disappearing at a rate of two breeds a week. This has far-reaching consequences, not only for our generation but also for the generations to come (Geerlings et al. 2002).

Genetic resources are among the most valuable assets that a country holds. Human societies have, for at least 12 000 years, recognized the importance of these assets and have been engaged in the domestication of wild plants and animals to meet a variety of needs. Domestic animals make a major contribution to human requirements for food in the form of meat, milk, milk products, eggs, fibre, fertilizer for crops as well as draught power. The number of domestic animal species contributing to agriculture is low, with less than 30 species being used extensively, and with less than 14 species accounting for over 90 percent of global livestock production. However, whilst the number of species being used in the livestock sector is low, the genetic diversity of these species has been used extremely effectively. Farmers and breeders have successfully selected animals for a variety of traits and production environments, resulting in the development of over 6000 breeds of livestock (CBD 2001). From just nine of the 14 most important species (cattle, horse, ass, pig, sheep, buffalo, goat, chicken and duck) as many as 4000 breeds have been developed and used worldwide. The FAO's Domestic Animal Diversity Information System (DAS-IS) had, in March 2005, records of over 6900 breeds in 35 species from 180 countries, including information on origin, population, risk status, performance and morphology. Of these, over 700 are already extinct (see Table 1) and it is estimated that 30 percent of the world's breeds are at risk of extinction. 

These breeds commonly possess valuable traits such as adaptation to harsh conditions, including tolerance of parasitic and infectious diseases, drought and poor quality feed. They are being replaced in both developed and developing countries by a few high production breeds which, to be successful, require high inputs, skilled management and comparatively benign environments

Within the agricultural context, animal biodiversity is the genetic variability (or diversity) between breeds and within breeds of the same species. Within agricultural systems biological diversity is often referred to as "Agrobiodiversity".

There is still a large diversity in the genotypes of livestock species. This results from natural selection, reproduction in isolation, and from breeding for specific purposes. However, agrobiodiversity is declining due to an increase in communication, changed demand for livestock products and services, and innovations in the livestock sector resulting in more uniform conditions for livestock.

Gradual Change

This results from changes in the environment and therefore of genotype – environment interactions and natural selection. Investments are made to protect livestock from harsh conditions, feeding is improved and diseases are controlled with curative and preventative measures. Locally this results in a gradual change in genetic composition. Globally, the result is a reduction in agrobiodiversity. This process takes place in all livestock production systems.

Global Decline

Global decline in genetic diversity is also the result of the use of increased numbers of livestock from a small number of selected breeds. Changes in the productive environment create opportunities for use of exotic breeds where many years of selection has concentrated on production characteristics. Through replacement and cross-breeding the local variation in genetic composition initially increases but decreases as the characteristic of the local breeds are lost over time. The number of highly productive breeds is relatively small. Technical innovations in transport, communication and reproduction (hatcheries, AI, embryo transfer) facilitate the use of these few breeds on a world-wide basis and their representation in the livestock population is increasing.

The import of exotic breeds can result in activities within the livestock sector that are uneconomic and / or have a negative impact on the environment. In many cases these activities are subsidized or otherwise provided for by development programs. Measurements to support livestock production include for example:

• tsetse control to create an environment for Trypanosomiasis sensitive cattle breeds;
• tick and tick borne disease control to reduce losses and enhance productivity of exotic breeds and cross breeds.

More recently alternative approaches have been promoted, but usually at a small scale, e.g.:

• re-introduction of trypano-tolerant breeds and selection on trypano-tolerance in Western and Central Africa;
• cross-breeding and selection for tick and tick borne disease tolerance in Australia and Eastern Africa.

The focus in the earlier approaches is on changing the environment to create opportunities for exotic breeds to be productive. In the more recent approach the focus is on accepting certain constraints of the environment and using breeds that can cope with these constraints. A parallel can been seen in the crop sector: chemical pest control versus selection on disease resistance.

Maintenance of the genetic diversity of livestock is therefore important.

The demand for milk, meat and eggs is developing faster than that for other livestock products and services as such as hair, wool, animal traction and transport (where demand is usually decreasing). In the competition for scarce resources, species and breeds renowned for these more traditional products and services (camels, donkeys, horses, buffalo, elephants, llama's, yak, wool sheep, etc) are at the loosing end, also in the resource driven farming systems. Gradually nomads and farmers replace traditional species and breeds by species and breeds that have a greater productivity and therefore higher economic value in the short term. As a result, population sizes of these traditional breeds is decreasing, their management gets poorer and performances decline. Some of these breeds have been included in breeding programs aiming at safeguarding them for the purpose of genetic diversity. However, these programs are costly and can only survive when external parties show an interest in keeping them.

The impact of the environment on the genetic composition of breeds and the use of certain species is highest in the extensive grazing and the mixed farming grazing systems. Because of the large diversity in ecological settings there is a large diversity in genetic composition amongst the breeds in these systems. Many of these systems make use of environments that are marginal for other uses but rely for certain periods of the year on environments that have a higher potential (i.e. flood plains and mountain valleys). Increased competition for the use of these areas is a thread for these extensive livestock systems and so for the global genetic diversity of livestock species.

Advantages of Agrobiodiversity

The present high-input high-output industrial agricultural systems are characterized by the use of high levels of fertilizers and good quality feed concentrates. Within these systems veterinary treatment with drugs for preventive and clinical use is sometimes practiced at a high level. Environmental problems and resistance against drugs can create conditions for animal production in which higher levels of feed conversion efficiency and disease resistance are required. The conservation of biodiversity is required as sources of genes, which are necessary as an insurance against changes in production circumstances, or the threat of a new disease. Animal production geneticists world-wide are searching for genes which influence the production, quality of products, and the health or reproduction traits of animals. In this search, crosses between breeds with extreme characteristics play an important role. This type of crossbreeding requires a high level of biodiversity within the species. The existence of many local breeds contribute to such a biodiversity.

Results of experience and research show that greater levels of agrobiodiversity can:

• Contribute to improved disease resistance;
• Diversify products and income opportunities, and reduce risks to individuals and nations;
• Increase productivity, food security, and economic returns;
• Reduce dependency on external inputs;
• Improve human nutrition
• Help maximize effective use of resources and the environment
• Conserve ecosystem structure, reduce the pressure of agriculture on the environment, and help maximize effective use of resources and the environment;
• Make farming systems more stable, robust, and sustainable, and contribute to sustainable intensification.

"FAO estimates that somewhere in the world at least one breed of traditional livestock dies out every week. Many traditional breeds have disappeared as farmers focus on new breeds of cattle, pigs, sheep, and chickens. Of the 3,831 breeds of cattle, water buffalo, goats, pigs, sheep, horses, and donkeys believed to have existed in this century, 16 percent have become extinct, and a further 15 percent are rare. Some 474 of extant livestock breeds can be regarded as rare. A further 617 have become extinct since 1892. Over 80 breeds of cattle are found in Africa, and some are being replaced by exotic breeds. These losses weaken the potential of breeding programs that could improve hardiness of livestock."

A number of factors are considered as being mainly responsible for the declining genetic diversity of livestock:

• Destruction of the native habitats of some livestock breeds.
• The development of genetically uniform livestock breeds.
• Farmer and/or consumer preferences for certain varieties and breeds (and changes in these consumer preferences over time).
• Market forces from competing commercial groups (e.g. supermarkets) where low prices are viewed as being more important than quality and taste.

Of these, commercial interests are considered as creating the most important pressures on livestock diversity. Factors in determining the direction and nature of change include:

• Growth performance (productivity). This is by far the most important factor.
• Pest and disease resistance. This is less important to large scale commercial producers where the widespread use of antibiotics, pesticides and other chemicals compensates for loss of disease resistance. In general, the loss of diversity reduces the resistance to disease.
• Ease of handling,
• Adaptation to current levels of technology,
• and to a relatively minor extent, consumer choice.
  

Causes of Loss of Genetic Diversity in Domestic Animals

Source: Adapted from Intermediate Technology (1996)

These trends are supported by:

Ironically, the loss of indigenous breeds that are able to exploit vegetation in the more extreme environments may also seriously affect the capacity of some societies to live in significant areas of the world in a sustainable manner.

State

Declining livestock diversity has serious consequences for current livestock production and future capacity to meet unforeseen challenges and opportunities. Livestock diversity is being lost partly because of commercial production.

For instance, commercial production of egg chickens, meat chickens, and turkeys is dominated by fewer than 10 multinational breeding companies. Breed-level diversity within egg and meat-producing types is low because common breed origins and intense selection for similar production goals have promoted genetic uniformity. Similarly, records in the Domestic Animal Diversity database (DAD-IS) indicates that China possessed 128 pig breeds, of which 10 are now extinct and a further 10 are either critical or endangered as they are replaced with western breeds.

Traditional pastoralists have often tended to foster biodiversity, in both plants and animals. Many pastoral societies have developed elaborate systems that result in the preservation of genetic resources. Pastoralists have deliberately developed livestock to meet different needs and conditions. For example, a least 12 breeds of camel are known from southern Sudan alone. However, wealthier sectors of society are now accumulating large livestock holdings through purchase of animals from different areas and tribal groups - with the resulting cross-breeding making camels of one generic type.

It is clear that livestock breeds are not biological taxa but rather represent the outcome of social processes. They are therefore unlikely to survive outside the social contexts and production systems that formed them. However, these losses weaken the potential of breeding programs that could improve hardiness of livestock.

Commercial breeds of livestock possess greater genetic variability than most crop varieties do. This diversity allows intensification of selection within breeds to be a fruitful approach for improving livestock productivity. However, if continued emphasis on breed replacement and increasing selection intensity (e.g. for greater productivity) take place at the expense of maintenance of genetic diversity, including the advantages of disease resistance and environmental adaptation, there may be significant long-term costs. As an example, Holstein cattle have become the pre-eminent dairy breed world-wide and have enjoyed sustained improvements in milk production potential, but only at the cost of declining genetic diversity within the breed.

Despite significant advances in the preservation of genetic diversity of crop varieties, for example through ex-situ preservation of germplasm and seed banks, little attention has been paid to conserving the genetic diversity of livestock species. The current dependence on in situ conservation by hobbyists is inadequate. Moreover, this form of breed preservation is currently largely limited to Europe and America. The significant livestock diversity in Africa, Asia and South America is largely unprotected.

State is therefore characterized by:

• Change in the number of individual livestock breeds that are routinely used by grazing, mixed and industrial livestock production systems;
• Increased uniformity of livestock products
• Increased genetic uniformity within individual livestock breeds
• Increasing sedentarization of livestock production
• Declining economic viability of traditional livestock production systems

 

Impact

High Performance Breeds May Not be High Performers

For decades, local or indigenous livestock breeds were regarded as inferior to the high-performance breeds developed in the North. Cross-breeding with exotic animals has led to the dilution of indigenous breeds, and this is one of several factors responsible for a very severe narrowing of the genetic base of our domesticated animals. But now more and more reports are indicating that the performance of indigenous breeds is equal to or even better than that of improved or cross-bred animals. In India, for instance, the enormous rise in the country's milk output is due to indigenous buffaloes, rather than cross-bred cattle. In Ethiopia, a detailed study comparing the outputs of improved goats (Anglo-Nubian x Somali) with those of local breeds revealed that improved goats, while they grew faster, were much more susceptible to weight loss during the dry season, thus offsetting the previous gains. Although they gave more milk per animal, this was not the case when the yield was calculated in relationship to body weight (see Köhler-Rollefson 2001).

Disease Resistance of indigenous breeds

One of the important traits of indigenous breeds concerns their ability to cope with local diseases. For instance, the Red Masai sheep has proven to be genetically resistant, or less prone, to infestation with intestinal worms (see in Geerlings et al. 2002). The Uda sheep of Northern Nigeria is much less susceptible to foot rot, while the Kuri cattle kept along the shores of Lake Tchad are very resistant to insect bites. N'dama and some other breeds of indigenous African cattle are resistant to infection with trypanosomes. Such disease resistance is compromised when animals are selected only for high productivity. For example, the Orma Boran cattle kept by the Orma people in the Tana River District of Kenya are much more resistant to trypanosomes than their relative, the Improved Kenya Boran, which has been selected for meat gains over several generations. Thus in areas where tsetse pressure is high, the Orma Boran gains weight faster than the Improved Kenyan Boran. Similarly, local "backyard" chickens are likely to be more resistant to diseases and to certain parasites than are the "improved" breeds.

Response

It is important that the genetic diversity of rare and endangered livestock breeds and their wild relatives and ancestral lines be preserved as insurance against future needs.

Formal government-sponsored international programs for in-situ and ex-situ preservation of livestock genetic diversity need to be established. This is gradually becoming established through the efforts of the FAO Domestic Animal Diversity programme. However, there needs to be a far greater awareness of the problem. In addition, the native habitats of the wild relatives of livestock species must be preserved. Investments in preserving this natural capital could yield net payoffs in both agricultural productivity and profitability. Such investments should be considered in any economic cost-benefit analyses of alternative production regimes.

A move towards sustainable agriculture requires changes in production methods, concepts, and policies, as well as the participation of local people. Scientific advancements in genetics and "improved" varieties can have important roles. However, these need to be reoriented towards conserving and using diversity in farming systems - rather than replacing diversity with uniformity. The following principles are important:

• It is possible, with appropriate agricultural practices, for significant genetic diversity to be maintained within agricultural production systems, both within individual farms and among farms across a region.
• Participation and empowerment of farmers and indigenous peoples, and protection of their rights, are important means of conserving agrobiodiversity in research and development.
• Creating a supportive policy environment, including the elimination of incentives for uniform varieties, and implementing policies for local rights to genetic resources are important for agricultural biodiversity enhancement and food security.
• Application of agroecological principles helps conserve and enhance diversity on farms and can increase sustainable productivity.
• Adaptation of methods to local agroecological and socio-economic conditions, building upon existing successful methods and local knowledge, is essential to link biodiversity and agriculture and to meet livelihood needs.
• Conservation of plant and animal genetic resources, including in-situ methods, protects biodiversity to enhance current livelihood security as well as future needs.
• Reforming genetic research and breeding programs for enhancement of agricultural diversity is essential and can also have production benefits.

Response must therefore be characterized by:

• Development and transfer of technologies relevant to the sustainable use of biological diversity, including agricultural diversity;
• Development of policies and programmes targeted at the maintenance of local breeds of livestock;
• Creation of an enabling environment for economically viable production systems utilizing local breeds. Provision of incentives for the maintenance of local breeds;
• Monitoring numbers and population sizes of local breeds;
• Research targeted towards the identification and utilization of important characteristics inherent in local breeds of livestock;
• A reassessment of the value of products and services from local breeds in comparison with alternatives by fully taking into account the environmental costs and the real costs of veterinary services, disease control and other services.
  

Conservation of Livestock Diversity

Conservation of animal genetic resources is essential to enable farmers to adapt to changing environmental conditions and consumer demands. Variation in environmental conditions such as disease outbreaks, drought, floods and climatic anomalies, as well as changes in consumer preferences, is inevitable. It is therefore in the best interest of societies to ensure that farmers and breeders have access to the widest possible range of animal genetic resources so that they can effectively respond to change. It is impossible to predict the nature of the change, but change is certain, and the livestock sector must not be left without its animal genetic diversity insurance policy.

Conservation of animal genetic resources is also essential to fully realize the investment that has been made over many human generations in developing these resources. Also, ensuring the conservation of wild species will provide opportunities to further develop and expand the livestock sector. Identification of wild species with potential to contribute to agriculture, and integration of agricultural biodiversity conservation strategies and plans with general biodiversity conservation initiatives is essential.

Conservation of animal genetic diversity is a global issue, as all countries benefit from the use and development of domestic animals and their many products. Conservation of animal genetic diversity over the long-term, will enable countries and their farmers to better respond to changing environmental conditions and consumer preferences, to pursue new economic opportunities and to reduce their vulnerability to food shortages.

Conservation and sustainable use of animal genetic resources are essential to support and inform the biotechnology industry and other industries that are dependent on genetic resources. Technological developments are increasingly improving our capacity to use and develop genetic resources, and thus, it is imperative that the current rapid erosion of animal genetic resources is addressed.

Geerlings, E., Mathias, E. and Köhler-Rollefson, I. (2002). Securing tomorrow's food. Promoting the sustainable use of farm animal genetic resources. Information for action. League for Pastoral Peoples, Ober-Ramstadt, Germany.

Köhler-Rollefson, I. (2001). Intellectual property rights regime necessary for traditional livestock raisers. Indigenous Knowledge and Development Monitor, March 2001.

Sperling, L. and Loevinsohn , M. (eds). (1997). Using Diversity: Enhancing and Maintaining Genetic Resources On-farm. IDRC 1997. ISBN 0-88936-833-3. Available online at: http://www.idrc.ca/en/ev-9290-201-1-DO_TOPIC.html.