Number 65 Issue Paper September 2019 Protecting Food Animal Gene Pools for Future Generations A paper in the series on The Need for Agricultural Innovation to Sustainably Feed the World by 2050 Using different preservation techniques, breeds such as the Mulefoot hog, Buckeye chicken, San Clementine goat, Gulf Coast sheep, and Narragansett turkey can be preserved to ensure genetic diversity in livestock and poultry around the world. (Photo collage by Megan Wickham. Photos courtesy of the USDA, Wikimedia Commons, and Curtis Youngs.) ing. The number of breeds has declined urgent need to develop and maintain ABSTRACT as farming practices have focused on a an intensive program of sampling and The world’s population is expected to small number of high-producing breeds evaluation of the existing gene pools. reach more than 9 billion by 2050, creat- to meet low-cost market demands. In Genetic diversity can be preserved ing a grand societal challenge: ramping fact, up to 25% of global livestock through living populations or cryopre- up agricultural productivity to feed the breeds are either at risk of being lost, or served for future use. Living populations globe. Livestock and poultry products have already been lost. In the face of the can adapt to changes in the natural or are keys to the world supply of protein, mounting depletion in genetic diversity production environment, provide value but genetic diversity of livestock is fad- among livestock species, there is an in research, and contribute to specialty This material is based upon work supported by the U.S. Department of Agriculture’s (USDA) Agricultural Research Service (ARS) and Animal and Plant Health Inspection Service (APHIS) Agreement No. 59-0202-5-002. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of USDA–ARS, USDA–APHIS, any other USDA agency, or the USDA. CAST Issue Paper 65 Task Force Members Authors Dr. Robert L. Taylor, Jr., Division of Dr. Terry Stewart, College of Agri- Animal and Nutritional Sciences, West culture, Purdue University, West Dr. Julie A. Long (Chair), Animal Virginia University, Morgantown, West Lafayette, Indiana Bio-sciences & Biotechnology Virginia Dr. Terrence R. Tiersch, Aquatic Laboratory, U.S. Department of Dr. Fred Silversides, Chilliwack, British Germplasm and Genetic Resources Agriculture–Agricultural Research Columbia, Canada Center, School of Renewable Service, Beltsville, Maryland Dr. Curtis R. Youngs, Department of Natural Resources, Louisiana State Dr. Harvey Blackburn, National Animal Science, Iowa State University, University Agricultural Center, Animal Germplasm Program, U.S. Ames, Iowa Baton Rouge, Louisiana Department of Agriculture–Agricul- tural Research Service, Ft. Collins, Colorado Reviewers CAST Liaison Dr. Robert Evans, Elanco Animal Dr. Alison Martin, The Livestock Dr. Janet E. Fulton, Hy-Line Interna- Conservancy, Pittsboro, North tional, West Des Moines, Iowa Health, Harrisonburg, Virginia Carolina markets. Cryopreservation offers rare 2014), will be largely nourished. Ani- there is a global contraction in genetic and major breeds a benefit—whether to mals are an important source of human diversity” (USDA-NGRAC 2018). The reconstitute lost bloodlines or to serve as dietary protein, supplying one-third of the contraction is more evident when moving a safety net in case of catastrophic loss protein consumed in the world, as well beyond the handful of productive breeds, of a diminished population. This paper as micronutrients vital for infant brain where up to 20% of livestock and 79% of addresses several important challenges development. poultry breeds are classified as “at risk” regarding the effective protection of The United States has one of the most for extinction (FAO 2007). remaining livestock and poultry genetic vibrant livestock sectors in the world. Two examples of American breeds that diversity: (1) characterizing the animal Livestock breeders produce the genetic are considered rare, but that possess eco- populations to identify unique attributes resources necessary to address domes- nomically important traits, are the Gulf that will influence the collection and tic consumption and supply genetic Coast sheep and the Narragansett turkey. conservation of breeds; (2) improving resources to the world. For example, in The Gulf Coast sheep breed is resistant cryopreservation technology for a variety 2017 the United States exported approxi- to internal parasites, foot rot, and other of germplasm and cell types that targets mately $175 million of bull semen for use common sheep diseases; however, there biological differences impeding success in other countries compared to domes- are fewer than 200 pedigree registra- among species; (3) expanding the con- tic sales of approximately $22 million tions1 per year in the United States and an tent, accessibility and cross-talk among (https://www.naab-css.org/semen-sales). estimated global population of less than databases housing breed and genetic The productivity of the U.S. livestock 2,000 individuals. Parasitism is widely resource information; and (4) developing sector, however, is based upon ready recognized as the most important health private-public partnerships among rare access to and use of highly specialized issue of sheep and goats, and the costs of breed associations/curators, agricultural genetic resources, and there is cause for prevention, treatment, and lost produc- universities, federal agencies and non- concern at multiple levels. The highly tion worldwide are proposed to be tens of governmental organizations to ensure specialized livestock industries in North billions of dollars (Roeber et al. 2013); the long-term operational continuity of America are dominated by a small num- thus, genetic resistance to parasites is germplasm repositories. ber of productive breeds for which there an important prevention strategy. The is a concomitant downward trend in the Narragansett turkey, named for the bay effective number of breeding animals and in Rhode Island where it was developed INTRODUCTION a general contraction of genetic diversity, in the 1800s, not only is one of the oldest Seven domesticated species (cattle, particularly in the commercial dairy and turkey breeds but also possesses genes sheep, goats, pigs, chickens, turkeys, and poultry breeds. This problem has been ducks) account for most of the world’s noted in the recent National Genetics Re- 1 Registration identifies an animal as the product livestock and poultry food production sources Advisory Council’s Animal Ge- of a known sire and dam, born on a known date. (FAO 2019). It is from this handful of netic Resources summary, where it was Among livestock, primarily breeding animals have stated that “all livestock and poultry spe- their pedigrees registered with associations that track domesticated species that the world’s each breed; thus, annual registrations are a strong population, expected to reach 9.6 billion cies and breeds share a common genetic indicator of breeding population size and are used in less than 35 years (Searchinger et al. resource problem to varying degrees: by conservation organizations in most countries. 2 COUNCIL FOR AGRICULTURAL SCIENCE AND TECHNOLOGY for important economic traits—such as was the first animal to be sequenced for be administered by the ARS. The NAGP early maturation, egg production, meat the construction of the bovine genome repository currently houses cryopreserved quality, and disposition—and has broader (The Bovine Genome Sequencing and germplasm from the major livestock genetic variation than commercial turkey Analysis Consortium et al. 2009), due to (cattle, goat, sheep, and pig), and poultry lines (Aslam et al. 2012; Kamara et al. the uniformity of this unique stock after (chicken and turkey) species, as well as 2007). There are no more than seven pri- 75 years of selective breeding. As another major aquatic species. This collection mary Narragansett breeding flocks in the example, the University of Nebraska includes a number of rare and minor United States, and the estimated global developed a unique line of pigs with su- breeds such as the Gulf Coast sheep but population is less than 5,000. perior reproductive qualities for ovulation lacks many of the other minor breeds Although the rare livestock and poul- rate and embryonic survival (Johnson et (e.g., Narragansett turkey). There are try breeds are currently not major contrib- al. 1999) which not only helped elucidate additional gaps in the germplasm collec- utors to modern U.S. agriculture, one can the molecular basis of ovarian physiology tion for other rare and minor breeds for examine the recent outbreaks of highly in swine (Caetano et al. 2004), but also all of the major livestock species. In the pathogenic avian influenza in the United could be sought by swine producers in face of the mounting depletion of genetic States (or outbreak of African swine fever the future, similar to the Line 1 Hereford. diversity among livestock species, there in China) and realize that over-reliance The Avian Disease and Oncology Labora- is an urgent need to expand the sampling on a few highly-productive breeds could tory of the ARS maintains more than 30 program, sustain the preservation effort, endanger the global food supply if these lines of layer chickens, some of which and evaluate the remaining livestock and productive breeds are highly susceptible have been developed with resistance to poultry gene