Conservation and utilization of livestock genetic diversity in the United States of America through gene banking

Authors: Blackburn, Harvey; Wilson, Carrie - Welsh; Krehbiel, Bethany

Submitted to: Diversity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2019
Publication Date: 12/17/2019
Citation: Blackburn, H.D., Wilson, C.S., Krehbiel, B.C. 2019. Conservation and utilization of livestock genetic diversity in the United States of America through gene banking. Diversity. 11(12):244. https://doi.org/10.3390/d11120244.
DOI: https://doi.org/10.3390/d11120244

Interpretive Summary: Gene banking animal genetic resources provides an effective approach to conserve major and minor livestock breeds. In the United States a broad array of breeds have been conserved in a gene bank operated by the USDA. Currently the gene bank has over one million samples from approximately 165 breeds. Gaps in the collection exist for breeds with population sizes of less than 1,000 animals. While collection efforts continue for rare breeds the collection has already been used by breeders of rare breeds and there are a number of innovative approaches concerning how the collection can be used for the rarest of breeds. Given the array of obstacles confronting rare breeds the gene bank may be the most secure prospect for long term conservation of rare breed genetics.

Technical Abstract: A germplasm collection of over one million samples from over 55,000 animals that represent 165 livestock and poultry breeds has been developed to provide genetic conservation and security for the U. S. livestock sector. Samples in the collection span 60 years, suggesting a wide range of genetic diversity and genetic change is represented in the collection for rare and major breeds. Classifying 135 mammalian breeds into four groups (<1,000, <5,000, <20,000, and >20,000 animals) based upon animal registrations or census information indicates that 50% of the collection is comprised of rare breeds in the <1,000 category. As anticipated, collections for breeds in the <20,000 and >20,000 are more complete (86.1% and 97.7%, respectively) based upon an index combining number of germplasm samples and number of animals. For the rarest of breeds (<1,000) collection completeness was 45.3%. Samples from over 6,000 animals in the collection have been used for: adding diversity to breeds, genomic evaluation, reconstituting populations, or various research projects. Several aspects of collecting germplasm samples from rare breeds are discussed. In addition, approaches that could be used to enhance the status of rare breeds via repository use. However, given the array of obstacles confronting rare breeds the gene bank may be the most secure prospect for long term conservation of rare breed genetics.