Livestock Diversity: Storing Genes for the Future
Agricultural Research Service
The National Animal Germplasm Collection, part of the Agricultural Research Service (ARS), is ensuring that our livestock genetic diversity doesn’t disappear.
The mission is to build a germplasm collection as diverse as our present livestock populations as insurance against disasters like the foot-and-mouth disease outbreak that hit Britain in 2001. An incident like that could easily decimate the gene pool of a livestock species and cost billions in lost revenue, explained ARS geneticist Harvey Blackburn, who oversees the Collection. And dead is dead-and-gone if there aren’t backups in the freezer as the National Animal Germplasm Collection has in Fort Collins, Colorado, he added.
As the world’s largest gathering of genetic material from food and fiber animals, the Collection stores nearly a million samples from 31,000 domestic animals. This includes conventional livestock like pigs, chickens and cattle, and farmed fish like trout, as well as unexpected species such as bison, elk and even yaks, because they are also raised for food and wool.
Right now, the Collection is helping to pry open a genetic bottleneck in the Holstein dairy breed, which has had a decline in fertility and genetic diversity. All pedigrees of Holstein A.I. sires (providers of semen for artificial insemination) currently trace back to just two bulls in the 1880s.
But at least two other lineages from the 1880s existed as late as the 1960s. With its reputation for preserving genetic diversity and making such material publicly available, the Collection was able to acquire donations of frozen semen from both lines, which should help the breed’s gene pool.
Bison, once only wild animals, have been gaining popularity as livestock, with about 400,000 now being raised for meat. While there may not be a strong breed association currently keeping track of bison pedigrees, the Collection is already storing bison semen to preserve the species’ diversity before any genetic bottlenecks develop, Blackburn said.
Bison have been at such a point before, when hunting reduced their herds to 541 individuals in the 1880s. The Collection’s storage means never having to risk another genetic narrowing.
ARS is the chief intramural scientific research agency of the U.S. Department of Agriculture.