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===Sustainable Use of AnGR===
===Sustainable Use of AnGR===


There are many forms of livestock-keeping, that all have their own pros and cons in terms of maintaining genetic diversity.

:::'''Industrial livestock production'''
:::Industrial livestock production or intensive animal farming is a modern form of farming that uses higher stocking densities than is usually the case with other forms of animal agriculture.

:::'''Small scale livestock production'''
:::Small-scale livestock production entails less intensive production cycles, access to outdoors or pasture, minimal use of antibiotics, and a connection to local niche markets. This type of livestock production can be maintained in urban and rural settings. There are advantages and disadvantages to each. While it is more difficult to find land for livestock in urban settings, incorporating livestock to small-scale farms can greatly increase the local food supply, reduce garden waste, and provide manure. <ref name="smallscale f">Margo Hale, Linda Coff ey, Terrell Spencer, and Andy Pressman, NCAT Agriculture Specialists Published Sept. 2011 © NCAT ''[http://arcd.org/wp-content/uploads/2015/09/smallscalelivestock.pdf Small-Scale Livestock Production]''.</ref> Urban environments can also provide excellent foraging for [[Bee|bees]], with less exposure to the [[Pest|pests]], [[Disease|diseases]], and even [[Pesticide|pesticides]] that can be devastating to a colony.<ref name="smallscale f"/> Conversely, rural small-scale livestock production is traditionally more common, and allows for larger-scale operations. However, access to veterinary and other health-related services in poor urban areas may limit their access to formal markets. Close rural-urban linkages are important to overcome constraints of feed scarcity and to better utilize the advantages of each system.<ref name= "First report"/>

:::'''Pastoralism'''
:::Pastoralism plays an important role in livestock management and food security, since pastoralists can produce food where no crops can grow. Pastoralists move their livestock herds based on the season, which is also, known as [[Transhumance|transhumance]]. [[Nomadic pastoralism|Nomadic pastoralists]] follow an irregular pattern of movement. Current issues that pastoralists face include conflict over land rights, access to water, limited food resources, integration into global markets, and animal diseases. Climate change has been believed to have a negative impact on pastoralists, but evidence suggests that the root causes of land disputes are historical and political, rather than climate-related.<ref>Tor A. Benjaminsen. Sept. 2016. International Institute for Environment and Development. "Does climate change cause conflicts in the Sahel?" http://www.iied.org/does-climate-change-cause-conflicts-sahel </ref> Land rights are an issue for pastoralists, as many governments and organizations, including conservation efforts may restrict their access to valuable resources and land.


===Conservation===
===Conservation===

Revision as of 16:04, 4 November 2016

Animal genetic resources for food and agriculture are a subset of genetic resources (defined by the Convention on Biological Diversity as “genetic material of actual or potential value”[1]) and a specific element of agricultural biodiversity. The term animal genetic resources is often used to refer specifically to the genetic resources of avian and mammalian species used in or potentially used for food and agriculture purposes.[2] [3] The term “animal genetic resources for food and agriculture” is often shortened to “farm animal genetic resources” or simply “animal genetic resources” and sometimes referred to as “livestock biodiversity” or simply “livestock diversity”.

Animal genetic resources can be embodied in live populations or in conserved genetic materials such as cryoconserved semen or embryos. The diversity of animal genetic resources includes diversity at species and breed and within-breed level.[3] There are currently known to be some 8,800 different breeds within 38 species of birds and mammals that are currently used for food and agriculture.[3] The main animal species used for food and agriculture production are cattle, sheep, goats, chickens and pigs. In the livestock world, these species are often referred to as “the big five”. Some less-utilized species include the dromedary, donkey, bactrian camel, buffalo, guinea pig, horse, rabbit, yak, goose, duck, ostrich, partridge, pheasant, pigeon, and turkey.

  • Cattle
    Cattle
  • Chicken
    Chicken
  • Goat
    Goat
  • Sheep
    Sheep
  • Pig
    Pig

History of Animal Genetic Resources

The history of animal genetic resources began about 12,000 to 14,000 years ago, during the domestication of major crop and livestock species in the early neolithic time period. This ability to control food production led to major demographic, technological, political and military changes. Following this initial domestication, thousands of years of natural and human selection, genetic drift, inbreeding, and crossbreeding have contributed to diversify animal genetic resources and have allowed livestock keeping to be practiced in a variety of environments and production system.[4] Few species have successfully been domesticated; out of the world’s 148 non-carnivorous species weighing more than 45 kg, only 15 have been domesticated.[5] The proportion of domesticated birds used for food and agriculture is even lower- 10 out of 10,000. The reason these numbers are so low is because it is rare to find species with all of the behavioral and physiological traits necessary for domestication. These traits include lack of aggression towards humans, a strong gregarious instinct, a “follow the leader” dominance hierarchy, a tendency not to panic when disturbed, a diet that can be easily supplied by humans (herbivores), a rapid growth rate, relatively short intervals between births, and large litter size.

The dispersion and migration of domesticated species has had an equally important impact on livestock diversity as their initial domestication. The origins and distribution of livestock diversity are central to its current utilization and long-term conservation.[6] The process of migration likely varied between regions, but certainly involved the movement of human populations and cultural exchanges between populations. In order to look back and determine where livestock domestication occurred, osteometric information from archaeological sites, and ancient livestock DNA studies are useful tools.

Additional factors such as mutations, genetic drift and natural and artificial selection have also played a role in shaping the diversity of livestock populations. As human and and animal populations migrated away from the sites of domestication, sub-populations of livestock were formed through geographic and genetic isolation, setting the foundation for the formation of breeds. Diversity increased among these sub-populations while uniformity increased within them. Intrabreeding within sub-populations and the increased fecundity of particular individuals that thrived in the local environment led to more or less distinct groups of animals that were naturally selected to be adapted to the prevailing environmental conditions. Human intervention through artificial selection of animals with desirable characteristics increased the differentiation among and uniformity within breeds. Examples of traits that have been deliberately selected for by humans include growth rate, milk or egg production, coat color, meat quality, and age of maturity, among many others. The process of artificial selection has been the reason for gains in output from commercial breeds, whereas the adaptation of indigenous livestock to diverse and challenging environments.[7] Selection, be it natural or artificial, generally results in reduced genetic variation.

Over the past 250 years the greatest changes in livestock diversity and creation of formal breeds have occurred mainly due to changes that began in England in the late 18th century. These changes have included development of systematic pedigree and performance recording and applying specific breeding objectives. This led to the fixation of breed-specific traits and an increase in productivity. Some breeds were intrabred as distinct, isolated populations, while many breeds continued to interact with each other as a result of intentional cross-breeding or unintended introgression. Before the end of the 19th century, several breeds had been absorbed by other populations.[8] In the 19th century, railways and steamships increased the long-distance transportation of livestock. After the Second World War, artificial insemination became common in cattle and pig breeding. As a result of these developments, a limited number of trans-boundary commercial breeds, such as the Holstein cow and Large White pig, have become very widespread and increasingly dominate livestock production globally. [5]

Benefits and Uses of Livestock Diversity

The wide number of livestock breeds and the genetic diversity within them mean that animal genetic resources have a substantial value to society. The different breeds provide a wide range of products and services for the benefit of humankind. The diversity of animal genetic resources allows livestock to be raised successfully in a diverse range of different environments and underpins the supply of a range of different products and services: from meat, milk and eggs to fuel, manure and draught power.[3] Diversity also allows the flexibility to change breeding goals if needed and emphasize alternative traits in response to changes in markets or other conditions. Different breeds produce specific wool, hairs and leather for clothing, carpets and furniture and are often the basis for traditional garments. Local breeds that were developed by a given community often have a huge cultural significance for that community. Livestock are often a source of wealth and are critical for its maintenance. They appear frequently in art and often play key roles in traditional customs, such as religious ceremonies, sporting events and weddings. Breeds that have been developed primarily through natural selection have effectively evolved with their environments and usually provide ecosystem services, such as landscape management, vegetation control, and promotion of biodiversity, that are critical for maintaining those landscapes. For example, the Engadine sheep, which were near extinction in the 1980s, today help to preserve centuries-old grassland in the Alps by eating invasive shrubs.[9] Within breeds, greater genetic diversity allows for continued selection for improving a given trait, such as disease resistance.

Greater livestock diversity allows humans to be better prepared to meet future challenges, such as climate change. Having access to a range of diverse livestock traits may allow for greater ability to cope with harsh climates and emerging diseases. Animals with unique adaptive abilities, such as resistance or tolerance to diseases and pests, or ability to thrive on poor feed and cope with dry or hot climates can help humans be more resilient to changes in climate.

Threats to Livestock Diversity

Despite the importance of animal genetic resources and their diversity, their diversity has been continually decreasing over time. For example, the Pantaneiro cattle of Brazil are at risk of extinction. One of the greatest threats to livestock diversity is pressure from large-scale commercial production systems to maintain only high-output breeds.[2] Recent molecular studies have revealed that the diversity of today’s indigenous livestock populations greatly exceeds that found in their commercial counterparts.[5] Some other major threats to livestock diversity include climate change, inappropriate development of policies and management strategies, disease outbreaks, armed conflict and various types of natural disasters and emergencies.

Climate change and its impact on livestock is being studied. Changes in climate will have an impact on livestock and food production in many ways.[10][11] In Africa, different regions are predicted to experience different changes in weather patterns. For example, parts of Madagascar and Mozambique are predicted to have a drier than average rainy season, while just north in parts of central Africa, a wetter December–January is expected.[12]

Some major disease threats that livestock currently face include, rinderpest, foot and mouth disease, and Peste des petits ruminants (PPR), also known as sheep and goat plague.

Current State of the World's Animal Genetic Resources

The Food and Agriculture Organization of the United Nations (FAO) has taken initiative and published two global assessments of livestock biodiversity: The State of the World’s Animal Genetic Resources for Food and Agriculture (2007) and The Second Report on the State of the World’s Animal Genetic Resources for Food and Agriculture (2015).[3]

Although there currently exists many diverse species and breeds of animals used for food and agriculture production, there is more work to be done on classifying their risk of extinction; 17% of the world’s farm animal breeds are at risk of extinction and 58% are of unknown risk status, meaning the problem may thus be underestimated.[3] The world’s pool of animal genetic resources is also currently shrinking, with rapid and uncontrolled loss of breeds and conjointly their often uncharacterized genes. Nearly 100 livestock breeds have gone extinct between 2000 and 2014.[5] With the loss of these breeds comes the loss of their unique adaptive traits, which are often under the control of many different genes and complex interactions between the genotype and the environment.[3] In order to protect these unique traits, and the diversity they allow, collaborative global efforts towards the characterization and management of these genetic resources must be made. Unlike plants, which can be easily conserved in seed banks, a large portion of livestock genetic diversity relies on live populations and their interactions with the environment.

Progress is being made in the characterization and management of animal genetic resources for food and agriculture. Recent advances in molecular genetics have provided data on the history and current status of AnGR. Genetic markers and molecular studies are being used to characterize livestock diversity and to reconstruct the events that have shaped the present diversity patterns, including ancestry, prehistoric and historical migrations, admixture, and genetic isolation.[7] Exploration of the past is essential to understanding trends and to better characterize the current state of animal genetic resources. In 2009, six years after the completion of the human genome project, cattle became one of the first livestock species to have a fully mapped genome.[13]

Some general conclusions from recent molecular studies show that individual breeds only differ by typically 40% in total genetic molecular composition; species differ by about 80% of their genetic material. Additionally, breeds with well-defined and appreciated traits tend to be inbred and have low genetic diversity, while non-descript local populations tend to have high molecular genetic diversity.[14]

Management of Animal Genetic Resources

Characterization of AnGR

Characterization of AnGR is a prerequisite for its management. Advances in molecular genetics have provided us with tools to better understand livestock origin and diversity. There are many technologies capable of determining genetic profiles, including whole genome sequencing, shotgun sequencing, RNA sequencing and DNA microarray analysis. These techniques allow us to map genomes and then analyze their implications through bioinformatics and statistical analysis. Molecular genetic studies, especially genome-wide association studies and whole-genome sequencing allow adaptive traits to be linked to genomic regions, genes, or even mutations. For example, horn size, meat quality, gait, and prenatal growth in cattle all have single genes found to be responsible for these phenotypic traits.[15]

Specific regions of DNA, such as quantitative trait loci (QTL), are commonly used to recognize specific genetic traits. However, DNA polymorphisms that are not linked to specific traits are now more commonly used as markers for genetic diversity studies; Different levels of genetic diversity information can be obtained from different kinds of genetic markers. For example, autosomal polymorphisms are used for population diversity estimates, estimation of genetic relationships and population genetic admixture, whereas mitochondrial DNA polymorphisms are used to detect geographic regions of domestication[16], reconstructing migration routes[17] and the number of female founders[18]. This is possible because changes in mitochondrial DNA sequences only occur through the breeding of a wild female.

Some general conclusions from recent molecular studies show that individual breeds only differ by typically 40% in total genetic molecular composition, whereas the variation of genetic material between species is about 80%. Additionally, breeds with well-defined and appreciated traits tend to be inbred and have low genetic diversity, while non-descript local populations tend to have high molecular genetic diversity.[19]

Sustainable Use of AnGR

There are many forms of livestock-keeping, that all have their own pros and cons in terms of maintaining genetic diversity.

Industrial livestock production
Industrial livestock production or intensive animal farming is a modern form of farming that uses higher stocking densities than is usually the case with other forms of animal agriculture.
Small scale livestock production
Small-scale livestock production entails less intensive production cycles, access to outdoors or pasture, minimal use of antibiotics, and a connection to local niche markets. This type of livestock production can be maintained in urban and rural settings. There are advantages and disadvantages to each. While it is more difficult to find land for livestock in urban settings, incorporating livestock to small-scale farms can greatly increase the local food supply, reduce garden waste, and provide manure. [20] Urban environments can also provide excellent foraging for bees, with less exposure to the pests, diseases, and even pesticides that can be devastating to a colony.[20] Conversely, rural small-scale livestock production is traditionally more common, and allows for larger-scale operations. However, access to veterinary and other health-related services in poor urban areas may limit their access to formal markets. Close rural-urban linkages are important to overcome constraints of feed scarcity and to better utilize the advantages of each system.[21]
Pastoralism
Pastoralism plays an important role in livestock management and food security, since pastoralists can produce food where no crops can grow. Pastoralists move their livestock herds based on the season, which is also, known as transhumance. Nomadic pastoralists follow an irregular pattern of movement. Current issues that pastoralists face include conflict over land rights, access to water, limited food resources, integration into global markets, and animal diseases. Climate change has been believed to have a negative impact on pastoralists, but evidence suggests that the root causes of land disputes are historical and political, rather than climate-related.[22] Land rights are an issue for pastoralists, as many governments and organizations, including conservation efforts may restrict their access to valuable resources and land.

Conservation

Breeding management programs, including ex situ conservation with live animal populations, and in situ conservation involving the freezing of genetic materials are commonly used in AnGR conservation. In order to establish and strengthen these programs, more research on methods and technologies must be undertaken.

Each of the “big five” species are reported to be managed by a breeding program in the majority of country reports. The figures are higher for cattle (90%) than for other species (80%). The remaining species used for food and agriculture (besides horses (74%), buffaloes (58%) and Bactrian camels (80%)) have less than 50% of all countries reporting the presence of breeding programs.[3]

Policy for Animal Genetic Resources

The management of issues regarding AnGR is addressed by the Commission on Genetic Resources for Food and Agriculture (CGRFA), which is a body of FAO. In May, 1997, The CGRFA put together an Intergovernmental Technical Working Group on Animal Genetic Resources for Food and Agriculture (ITWG-AnGR).[23] The ITWG-AnGR’s objectives are to review the situation and issues related to agrobiodiversity of animal genetic resources for food and agriculture and advise and make recommendations to the Commission on these matters, and consider progress made.[24] This group worked with many partners and countries to produce the First Report on the State of Animal Genetic Resources, which served as the basis for creating the Global Plan of Action for Animal Genetic Resources (GPA). In 2007, the GPA was adopted by 109 countries as the first agreed international framework for the management of livestock biodiversity.[2] The implementation of the GPA is overseen, monitored and evaluated by the CGRFA. The funding for this program was acquired by voluntary donors under the guidelines of the Funding Strategy for the Implementation of the Global Plan of Action for Animal Genetic Resources.[25]

The regulation and enforcement of policies regarding access and benefit sharing of AnGR are currently regulated by the Nagoya Protocol on Access and Benefit sharing, which is an agreement to the 1992 Convention on Biological Diversity. The Nagoya Protocol entered into force on 12 October, 2014 and aims to provide a legal framework for the fair and equitable distribution of benefits arising from the utilization of genetic resources.[26] The lack of adequate policies on AnGR management can lead to marginalization of relevant stakeholders, such as pastoralists, who are valuable players in maintaining livestock diversity.

Patenting of AnGR increased in the late 1990s, focusing on expressed sequence tags (ESTs) and single nucleotide polymorphisms (SNPs). SNPs are important in marker-assisted breeding for the identification of traits such as meat or milk quality. At the same time, patenting activity involving transgenic livestock also increased. However, work on patents and characterization of AnGR declined sharply from 2001, caused by a combination of factors including an increasingly restrictive approach to the patentability of DNA sequences by patent offices and a lack of markets for food products from transgenic animals.[27] Trends in activity arising from genome sequencing projects merit careful attention with regard to their implications (positive or negative) for AnGR management.

Increasingly complex issues are emerging that require balancing the interests of many stakeholders. In a time of rapid and unregulated change, livestock and their products should be used sustainably, developed and ultimately conserved. National planning should integrate “consumer affairs, human health matters, and the management of new biotechnologies, as well as physical and spatial planning of animal production in the context of urban expansion and protected areas.”[2]

References

  1. ^ "Text of the Convention". Retrieved 20 September 2016.
  2. ^ a b c d FAO. 2007. The Global Plan of Action for Animal Genetic Resources and the Interlaken Declaration. Rome.
  3. ^ a b c d e f g h FAO. 2015. The Second Report on the State of the World’s Animal Genetic Resources for Food and Agriculture. Rome
  4. ^ FAO. 2007. The State of the World’s Animal Genetic Resources for Food and Agriculture, Section A. edited by B. Rischkowsky & D. Pilling. Rome.
  5. ^ a b c d FAO. 2007. The State of the World’s Animal Genetic Resources for Food and Agriculture, edited by B. Rischkowsky & D. Pilling. Rome.
  6. ^ Freeman, A.R., Bradley, D.G., Nagda, S., Gibson, J.P. & Hanotte, O. 2006. Combination of multiple microsatellite datasets to investigate genetic diversity and admixture of domestic cattle. Animal Genetics, 37(1): 1–9.
  7. ^ a b FAO. 2007. The State of the World’s Animal Genetic Resources for Food and Agriculture, pg 18. edited by B. Rischkowsky & D. Pilling. Rome
  8. ^ Felius, M., Theunissen, B. & Lenstra, J.A. 2015. On the conservation of cattle – the role of breeds. Journal of Agricultural Science, 153: 152–162.
  9. ^ FAO. 2015. The Second Report on the State of the World’s Animal Genetic Resources for Food and Agriculture. pg 76. Rome.
  10. ^ P.K. Thornton, J. van de Steeg, A. Notenbaert, M. Herrero, The impacts of climate change on livestock and livestock systems in developing countries: A review of what we know and what we need to know, Agricultural Systems, Volume 101, Issue 3, July 2009, Pages 113-127, ISSN 0308-521X
  11. ^ A. Nardone, B. Ronchi, N. Lacetera, M.S. Ranieri, U. Bernabucci, Effects of climate changes on animal production and sustainability of livestock systems, Livestock Science, Volume 130, Issues 1–3, May 2010, Pages 57-69, ISSN 1871-1413,
  12. ^ Monitoring for Environment and Security in Africa. accessed October, 2016. http://www.fao.org/docrep/010/a1250e/a1250e00.htm
  13. ^ Brown, David (23 April 2009). "Scientists Unravel Genome of the Cow". The Washington Post.
  14. ^ Groeneveld, L.F., Lenstra, J.A., Eding, H., Toro, M.A., Scherf, B., Pilling, D., Negrini, R., Finlay, E.K., 19 Origin and history of livestock diversity A THE second report on the state OF THE WORLD'S ANIMAL GENETIC RESOURCES FOr FOOD AND AGRICULTURE Jianlin, H., Groeneveld, E., Weigend, S. & the GOBALDIV Consortium. 2010. Genetic diversity in farm animals: A review. Animal Genetics, 41: 6–31.
  15. ^ FAO. 2015. The Second Report on the State of the World’s Animal Genetic Resources for Food and Agriculture. Rome. Table 1A2
  16. ^ Naderi, S., Rezaei, H.R., Pompanon, F., Blum, M.G., Negrini, R., Naghash, H.R., Balkiz, O., Mashkour, M., Gaggiotti, O.E., Ajmone-Marsan, P., Vigne, J.D. & Taberlet P. 2008. The goat domestication process inferred from large-scale mitochondrial DNA analysis of wild and domestic individuals. Proceedings of the National Academy of Sciences of the United States of America, 105: 17659-17664.
  17. ^ Groeneveld, L.F., Lenstra, J.A., Eding, H., Toro, M.A., Scherf, B., Pilling, D., Negrini, R., Finlay, E.K., 19 Origin and history of livestock diversity A THE second report on the state OF THE WORLD'S ANIMAL GENETIC RESOURCES FOr FOOD AND AGRICULTURE Jianlin, H., Groeneveld, E., Weigend, S. & the GOBALDIV Consortium. 2010. Genetic diversity in farm animals: A review. Animal Genetics, 41: 6–31.
  18. ^ Bollongino, R., Burger, J., Powell, A., Mashkour, M., Vigne, J.D. & Thomas, M.G. 2012. Modern taurine cattle descended from small number of Near-Eastern founders. Molecular Biology and Evolution, 29: 2101–2104.
  19. ^ Groeneveld, L.F., Lenstra, J.A., Eding, H., Toro, M.A., Scherf, B., Pilling, D., Negrini, R., Finlay, E.K., 19 Origin and history of livestock diversity A THE second report on the state OF THE WORLD'S ANIMAL GENETIC RESOURCES FOr FOOD AND AGRICULTURE Jianlin, H., Groeneveld, E., Weigend, S. & the GOBALDIV Consortium. 2010. Genetic diversity in farm animals: A review. Animal Genetics, 41: 6–31.
  20. ^ a b Margo Hale, Linda Coff ey, Terrell Spencer, and Andy Pressman, NCAT Agriculture Specialists Published Sept. 2011 © NCAT Small-Scale Livestock Production.
  21. ^ Cite error: The named reference First report was invoked but never defined (see the help page).
  22. ^ Tor A. Benjaminsen. Sept. 2016. International Institute for Environment and Development. "Does climate change cause conflicts in the Sahel?" http://www.iied.org/does-climate-change-cause-conflicts-sahel
  23. ^ FAO Animal Production and Health website. accessed Nov 2016 http://www.fao.org/ag/againfo/programmes/en/genetics/angrvent.html
  24. ^ FAO, 2016. Statutes of the Intergovernmental Technical Working Group on Animal Genetic Resources for Food and Agriculture Rome.
  25. ^ FAO, 2010.Funding Strategy for the Global Plan of Action Rome.
  26. ^ Nagoya Protocol from the Convention on Biological Diversity https://www.cbd.int/abs/ accessed Oct. 2016
  27. ^ Eirini Kitsara, WIPO, 2014. pg 338 of The Second Report on the State of the World's Animal Genetic Resources. Rome.
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