Cryoconservation of animal genetic resources is a strategy wherein samples of animal genetic materials are preserved cryogenically."Cryoconservation of Animal Genetic Resources", Rep. Rome: Food and Agriculture Organization of the United Nations, 2012. FAO Animal Production and Health Guidelines No. 12. Print.
Animal genetic resources, as defined by the Food and Agriculture Organization of the United Nations, are "those animal species that are used, or may be used, for the production of food and agriculture, and the populations within each of them. These populations within each species can be classified as wild and feral populations, landraces and primary populations, standardised breeds, selected lines, varieties, strains and any conserved genetic material; all of which are currently categorized as Breeds."FAO. "Annex 2: Working Definitions for Use in Developing Country Reports and Providing Supporting Data." Animal Genetics Resources Information: Special Issue State of the World 30 (2001): 35–40. Web. May 19, 2016. <http://www.fao.org/3/a-y1100m/y1100m03.htm >. Genetic materials that are typically cryogenically preserved include sperm (such as in a sperm bank), oocytes, embryos and somatic cells.Mazur, P., S.p Leibo, and G. E. Seidel. "Cryopreservation of the Germplasm of Animals Used in Biological and Medical Research: Importance, Impact, Status, and Future Directions." Biology of Reproduction 78.1 (2007): 2–12. Web.Solti, L., E.g. Crichton, N.m. Loskutoff, and S. Cseh. "Economical and Ecological Importance of Indigenous Livestock and the Application of Assisted Reproduction to Their Preservation." Theriogenology 53.1 (2000): 149–62. Web. Cryogenic facilities are called gene banks and can vary greatly in size usually according to the economic resources available. They must be able to facilitate germplasm collection, processing, and long term storage, all in a hygienic and organized manner. Gene banks must maintain a precise database and make information and genetic resources accessible to properly facilitate cryoconservation. Cryoconservation is an ex situ conservation strategy that often coexists alongside in situ conservation to protect and preserve livestock genetics.Hiemstra, Sipke Joost, Tette Van Der Lende, and Henri Woelders. "The Potential of Cryopreservation and Reproductive Technologies for Animal Genetic Resources Conservation Strategies." Cryobiology 63.3 (2011): 316–17. Web.
Cryoconservation of livestock genetic resources is primarily done in order to preserve the genetics of populations of interest, such as indigenous breeds, also known as local or minor breeds. Material may be stored because individuals shared specific genes and phenotypes that may be of value or have potential value for researchers or breeders. Therefore, one of the main goals remains preserving the gene pool of local breeds that may be threatened.Verrier, E., Danchin-Burge, C., Moureaux, S., Ollivier, L., Tixier-Boichard, M., Boichard, D., ... & Clement, F. 2003. What should be preserved: genetic goals and collection protocols for the French National Cryobank. InProceedings of the Workshop on Cryopreservation of Animal Genetic Resources in Europe: February 23, 2003; Paris (pp. 79–89). Indigenous livestock genetics are commonly threatened by factors such as globalization, modernization, changes in production systems, inappropriate introduction of major breeds, genetic drift, inbreeding, crossbreeding, climate change, natural disasters, disease, cultural changes, and urbanization.Global Plan of Action for Animal Genetic Resources and the Interlaken Declaration. Rep. Rome: Food and Agriculture Organization of the United Nations, 2007. FAO. Web. Mendelsohn, Robert. "The Challenge of Conserving Indigenous Domesticated Animals." Ecological Economics 45.3 (2003): 501–10. Web. Indigenous livestock are critical to sustainable agricultural development and food security, due to their: adaptation to environment and endemic diseases, indispensable part in local production systems, cultural significance, and importance to local rural economies. The genetic resources of minor breeds have value to the local farmers, consumers of the products, private companies and investors interested in crossbreeding, breed associations, governments, those conducting research and development, and non-governmental organizations.Hiemstra, S. J. "Cryopreservation Strategies for Farm Animal Genetic Resources in Europe." Published in Rare Breeds International 8th Global Conference on the Conservation of Animal Genetic Resources, Terkidag, Turkey. October 2011. 29–34. Web. May 19, 2016. http://rbiglobalconf2011.nku.edu.tr/ Therefore, efforts have been made by national governments and non-governmental organizations, such as The Livestock Conservancy, to encourage conservation of livestock genetics through cryoconservation, as well as through other ex situ and in situ strategies."Conservation Successes." The Livestock Conservancy. The Livestock Conservancy, n.d. Web. May 15, 2016. Cryogenic specimens of livestock genetic resources can be preserved and used for extended periods of time.Mazur, Peter. "Stopping Biological Time." Annals of the New York Academy of Sciences 541.1 (1988): 514–531. Web. This advantage makes cryoconservation beneficial particularly for threatened breeds who have low breed populations. Cryogenically preserved specimens can be used to revive breeds that are endangered or extinct, for breed improvement, crossbreeding, research and development. However, cryoconservation can be an expensive strategy and requires long term hygienic and economic commitment for germplasms to remain viable. Cryoconservation can also face unique challenges based on the species, as some species have a reduced survival rate of frozen germplasm.Menzies, Paula I."Artificial Insemination in Sheep." Management of Reproduction: Sheep: Merck Veterinary Manual. Merck Animal Health, June 2015. Web. May 13, 2016. http://www.merckvetmanual.com/mvm/management_and_nutrition/management_of_reproduction_sheep/artificial_insemination_in_sheep.html Mcevoy, T., G. D. Coull, P. J. Broadbent, J. S.M. Hutchinson, and B. K. Speake. "Fatty Acid Composition of Lipids in Immature Cattle, Pig and Sheep Oocytes with Intact Zona Pellucida." Journal of the Society for Reproduction and Fertility 118.1 (2000): 163–70. Web.
Description Cryoconservation is the process of freezing cells and tissues using liquid nitrogen to achieve extreme low temperatures with the intent of using the preserved sample to prevent the loss of genetic diversity.Yawn, David H. "Cryopreservation." Encyclopædia Britannica Online. Encyclopædia Britannica, n.d. Web. May 19, 2016. http://www.britannica.com/technology/cryopreservation Semen, embryos, oocytes, somatic cells, nuclear DNA, and other types of biomaterial such as blood and serum can be stored using cryopreservation, in order to preserve genetic materials. The primary benefit of cryoconservation is the ability to save germplasms for extended periods of time, therefore maintaining the genetic diversity of a species or breed. There are two common techniques of cryopreservation: slow freezing and vitrification. Slow freezing helps eliminate the risk of intracellular ice crystals.Loutradi, E. M., E. M. Kolibianakis, C. A. Venetis, E. G. Papanikolau, G. Pados, I. Bontis, and B.C. Tarlatizs. "Cryopreservation of Human Embryos by Vitrification or Slow Freezing: A Systematic Review and Meta-analysis." Techniques and Instrumentation 90.1 (2008): 186–93. National Center for Biotechnology Information. Web. If ice crystals form in the cells, there can be damage or destruction of genetic material. Vitrification is the process of freezing without the formation of ice crystals.Lovgren, Stefan. "Corpses Frozen for Future Rebirth by Arizona Company." National Geographic. National Geographic Society, March 15, 2005. Web. 13 May 16.
Value Cryoconservation is an indispensable tool in the storage of genetic material of animal origin and will continue to be useful for the conservation of livestock into the future. Cryoconservation serves as a way to preserve germplasms, which is particularly beneficial for threatened breeds. Indigenous livestock may be conserved for a variety of reasons, including the preservation of local genetics, their importance in local traditions and their value to the culture identity and heritage of the area.Oldenbroek, Kor, ed. Utilisation and Conservation of Farm Animal Genetic Resources. Wegeningen Academic Publisher, 2007. Web. The loss of regional livestock diversity could increase instability, decreases future possibilities and challenge production systems. Moreover, the maintenance of indigenous breeds can aid in the preservation of traditional lifestyles and livelihoods, even providing income through cultural tourism.Rahman, Gerold."Contribution of Rural Tourism to the Market for Livestock Products in LFAs in Germany." The James Hutton Institute. Livestock Systems in Integrated Rural Development, n.d. Web. May 16, 2016. Indigenous breeds can contribute to local economies and production systems by utilising land that is unsuitable for crop production to produce food products, as well as providing hides, manure and draft power. Therefore, the conservation and progression of these breeds are of the utmost importance for food security and sustainability.
Another beneficial factor in cryoconservation of indigenous livestock is in terms of food security and economic development.Barnes, K., T. Collins, S. Dion, H. Reynolds, S. Riess, A. Stanzyk, A. Wolfe, S. Lonergan, P. Boettcher, U. R. Charrondiere, and B. Stadimayr. "Importance of Cattle Biodiversity and Its Influence on the Nutrient Composition of Beef." Animal Frontiers Oct. 2012: 54–60. American Society of Animal Science. Web. Indigenous livestock often have beneficial traits related to adaptation to local climate and diseases that can be incorporated into major breeds through cryoconservation practices.Bett, Rawlynce, Mwai Okeyo, Birgitta Malmfors, Kjell Johansson, Morris Agaba, Donald Kugonza, A.K.F.H. Bhuiyan, Anibal Filho, Arthur Mariante, Fidalis Mujibi, and Jan Philipsson. "Cattle Breeds: Extinction or Quasi-Extant?" Resources 2.3 (2013): 335–57. Web. Cryoconservation is a favorable strategy because it allows germplasms to be stored for extended periods of time in a small confined area. An additional benefit of cryoconservation is the ability to preserve the biological material of both maternal and paternal cells and maintain viability over extended periods of time. Cryoconservation has been successfully used as a conservation strategy for species and breeds that have since been endangered. One drawback is that cryoconservation can only be done if preparation has taken place in advance. With proper preparation of collecting and maintaining genetic material, this method is very beneficial for the conservation of rare and endangered livestock. Cryoconservation can serve as a contingency plan when a breed population needs to be restored or when a breed has become extinct, as well as for breed improvement. This process benefits companies and researchers by making genetic materials available.
+ Conservation Goals Flexibility of country's AGR to meet changes Insurance against changes in production conditions Safeguarding against diseases, disasters, etc. Opportunities for genomic research Genetic Factors Allowing continued breed evolution/genetic adaption Increasing knowledge of phenotypic characteristics of breed Minimizing exposed to genetic drafts Sustainable utilization of total areas Opportunities for development in rural areas Maintenance of agro-ecosystem diversity Conservation of rural culture diversity