Location:2012 Annual Report
1a. Objectives (from AD-416):
1. Develop germplasm and DNA/tissue collection coupled with measurement of diversity. o Continue to develop germplasm collections across species and associated information. o Evaluate, refine and implement pedigree clustering approach for germplasm collection. o Pursue approaches to compare collection to in-situ populations using quantitative and/or molecular approaches. o Develop collections of DNA and/or tissues containing DNA and associated information. 2. Further develop the animal section of the GRIN network. o Develop database information system that documents the germplasm/tissue collection (Version 2) and has multi-location capacity. o Expand descriptors for all species as defined by species committees, and substantially increase data collection efforts. 3. Develop methods for population regeneration. o Computationally determine approaches for population regeneration and their management. 4. Improve cryopreservation methods for tissues. o Development of predictors/evaluation of post-thaw semen viability. o Procedures for collection and freezing of small ruminant and/or beef oocytes. o Determination of optimal semen cryopreservation diluents and freezing methodologies.
1b. Approach (from AD-416):
The over-arching goal of the National Animal Germplasm Program (NAGP) is to increase the security of U.S. livestock genetic resources by the development of a repository containing diverse livestock genetic resources. The proposed objectives of this plan are important because they will: strengthen the genetic diversity contained in the collection; improve the ability and efficiency of reconstituting populations through improved cryopreservation procedures and reconstitution strategies; and provide potential collection users with a more comprehensive understanding of what is contained in the collection through the GRIN database. Executing these objectives will require the utilization of quantitative and molecular genetics, reproductive biology, cryopreservation, and information systems science. The beneficiaries of this effort cover a wide spectrum including: livestock breeders; researchers reconstituting populations and performing various types of molecular studies; and the American public at large which benefits from the increased food security the program provides.
3. Progress Report:
Harvesting and transplanting chicken ovaries was shown to be an effective reconstitution strategy. Using this approach enabled populations to be reconstituted in one year and shorten reconstitution time by three years (Objective 1). Our techniques have also been applied to preservation of turkey ovaries from four Ohio State University populations (Subobjective 4B). Jersey Island’s Royal Jersey Agricultural and Horticultural Society sent semen samples from approximately 400 bulls to serve as a backup of their Jersey cattle that have been closed to any off-island genetics for approximately 200 years. This represents the first time a sovereign territory placed genetic resources with the NAGP program (Objective 1). The genetic diversity of US goat breeds (Spanish, Lamancha, Myotonic, Boer, and Angora) have not been quantified. Decreasing census counts for Spanish, Myotonic, and Angora breeds suggest such an assessment would be useful for conservation actions. Samples from these breeds were genotyped and analyzed in addition to five Brazilian breeds of goats were added to the analysis to determine genetic similarity to US breeds that also originated from the Iberian Peninsula. Key findings; Spanish and Angora breeds were the most genetically diverse populations; Angora is phenotypically distinct, its genetic distance from other breeds was not large; and the Boar goats, originally developed in South Africa, were the most genetically distant population. None of the genetic parameters evaluated indicated a lack of genetic diversity for US breeds (Objective 1). Predicting the fertilizing capacity of post-thawed semen is difficult. Improving the understanding of the sperm cell’s lipid and protein organization through the freezing and thawing process may provide insight into predictive approaches for fertilizing capacity. Using rooster sperm our results demonstrate the interaction and the changing nature of sperm’s lipid and protein architecture during the cryopreservation and thawing process. By understanding these dynamics we can initiate development of predictive approaches. This document serves as the final report for project 5402-31000-004-00D.(See new project 5402-31000-005-00D.) During the projects life cycle the collection has doubled in size. The diversity of the collection has broadened across species. Notably the first evaluations of genetic diversity using molecular approaches have been completed for cattle, sheep and goats which provide a basis to better understand the collection and potential gaps in the collection. Additionally, greater insight into global livestock genetic diversity enables the US livestock industry to respond to the challenges of food security, climate change, and economic viability. Advances in cryopreserving and transplanting chicken ovaries represent a major break-though for preservation and utilization of the species, with the potential for changing the way industry and universities utilize and maintain various populations. Animal-GRIN development efforts with Canada and Brazil creates new opportunities for improving the management of animal genetic resources nationally and internationally.
1. Chicken barrier broken – commercial populations preserved. The commercial poultry breeding industry has been reluctant to use cryopreservation and gene banking as a mechanism to protect their proprietary breeding lines. However, with improved semen handling protocols, and the ability to transplant gonadal tissue, gene banking of valuable breeding stock becomes a cost effective strategy. In cooperation with a private company, ARS scientists at the National Animal Germplasm Program, Ft. Collins CO initiated a process to backup germplasm of elite poultry populations. The ability to store germplasm of commercially important poultry lines will increase the efficiency with which elite genetic populations are managed.
2. Genetic security increased. Globally, genetic diversity is contracting across livestock species. This problem was addressed by the continued development of a comprehensive livestock germplasm collection at the National Animal Germplasm Program in Ft. Collins, CO. New germplasm acquisitions increased the level of genetic security for the livestock industry and research community. For example, the livestock sector has utilized 3,336 animals and 12,604 samples from the collection for research, or, for adding genetic diversity to live populations. By building and expanding the germplasm collection, the livestock industry and research community are able to access the collection’s genetic resources as needed.
Blackburn, H.D., Toishibekov, Y., Toishibekov, M., Welsh, C.S., Spiller, S.F., Brown, M.A., Pavia, S. 2011. Genetic diversity of Ovis aries populations near domestication centers and in the new world. Genetica. 139:1169-1178.