Is agriculture's drive toward uniformity and yield a draw against its genetic bank account? Not if idealism and economics can meet.

Over time, science has proven the value of genetic diversity. But more recently processing and retail value of uniform meat cuts has pushed livestock production toward a more narrow pool of genetics. The result is a sort of value paradox, taking advantage of the value of uniformity today at the possible expense of diversity tomorrow.

That paradox isn't lost on the students in Bill Lamberson's conservation biology classes at the University of Missouri-Columbia. Students there express concerns about the conservation of the nation's agriculture livestock gene pool.

"Students are ahead of the faculty in many ways and in many ways very idealistic," said Lamberson. "Because of that idealism, conservation genetics is likely to become more important. And in conjunction, the raising of endangered breeds may become more common as more individuals are educated as to its importance."

While many of Lamberson's students today have little background in production agriculture, they often express interest in rare breeds and about genetic diversity in all livestock. According to Lamberson, the genetic base of the world's Holstein cattle population can be traced to a mere 90 animals. Others estimate that number as less than 50.

"Those animals are all related and that is a narrow base for genetics," Lamberson said.

"Following the latest fad or modern trends does not necessarily create a strong breeding population in the long run."

Lamberson is working with the USDA's National Animal Germplasm Program (NAGP) at the University of Colorado in Fort Collins to identify the optimum set of animals for semen collection. Since the 1950s, the center has collected more than 400,000 varieties of plant seeds, but only began collecting animal semen in 1999.

'Noah's Ark on ice'
To remain viable, animal germplasm contained in semen and embryos must be frozen, or cryopreserved, in liquid nitrogen at minus 18 degrees Celsius. The NAGP collection currently includes more than 30,000 samples from beef and dairy cattle, poultry, sheep, goats and swine.

Because the program's goal is to capture as much genetic diversity as possible, selecting the best individuals from each breed and population is important. Toward that end, Lamberson developed a genetic algorithm to help make those determinations in swine.

"The algorithm's purpose is to identify a group for collection with the least level of relatedness among individuals within a population," said Lamberson, who developed the formula with his son, P.J., a mathematics graduate student at Columbia University, as they drove to Wyoming for a fishing trip. "Those individuals who are the least related are expected to provide the greatest number of unique genes, or alleles, and they best represent the population's genetic diversity."

Laura Melton, then an MU graduate student in animal sciences, helped Lamberson validate the algorithm's use as part of her master's thesis.

"In order for a population to be considered for inclusion, you first must have pedigree information as well as a certain minimum number of records on performance," she said. "Once you've established there is sufficient information to sample a population, you must then decide which individuals will be sampled."

Melton said for smaller populations, breed such as Hereford pigs, you want to take as broad a sample as possible, perhaps sampling from every individual. In larger populations, up to as many as 90 candidate animals could be sampled.

Once candidate animals have been identified, Melton said a relationship matrix is developed. Beginning with an arbitrary individual, the goal is to find the set of animals with the least degree of relatedness, those expected to provide the greatest genetic diversity.

Melton's validation study found the algorithm was suitable for use in genetic preservation projects such the NAGP initiative.

"The algorithm provided better results than both random and preselected random sampling," she said. "It reduced the relationship among selected animals and was better at capturing alleles."

Today, the algorithm also is being used to identify candidates for inclusion in cattle and other species.

Diversity watch
Finding a diverse range of genetics is not just an exercise in capturing a historic record of breeds. It's also a bellwether for what is happening today.

"We are not only developing a secure repository, but are studying in greater detail what's happening with various populations," said Harvey Blackburn, a geneticist at NAGP. "We are looking at which populations are decreasing and what trends are developing in these breeds."

University of Missouri swine breeding specialist, Tim Safranski, puts the project in the perspective of commercial livestock production.

"During the past two decades, U.S. livestock production has become much more standardized," said Safranski, who is a member of NAGP's swine species committee. "Producers have increased the use of genetic improvement technologies such as artificial insemination. While this has allowed for the production of uniform, high-quality consumer products, it also has reduced the total number of breeding stock in use. As a result, genetic diversity is being lost. And once it's gone, it's gone."

Safranski said maintaining diversity is crucial because it allows livestock producers to respond to changes in production environments, consumer demands and diseases. He cited the southern corn leaf blight outbreak of 1970--the greatest economic loss in a single crop in a single year in the entire history of agriculture--to demonstrate the importance of maintaining genetic diversity.

That year, the blight spread rapidly across the United States because U.S. corn varieties had little genetic diversity. About 80 percent of corn planted in 1970 was of a hybrid that had shown high resistance to the disease. However, a new variant of the blight had evolved to which the corn was susceptible. The outbreak destroyed 15 percent of the crop, and total losses were estimated at $1 billion.

"If earlier hybrids with genetic resistance to the disease had not been stored, who knows what would have happened to U.S. corn production?" Safranski said.

For his part, Blackburn, the NAGP geneticist, is pleased by a recent partnership with the American Hereford Association to collect semen from the North American Hereford cattle population. To illustrate the importance of the project, Blackburn alludes to a situation the herd faced in the 1950s when a recessive gene emerged, creating dwarfism in the Hereford population. That change in genetics threatened the future of the breed.

"It seems we must continually remind breeders that helping to maintain genetic diversity provides a long-term economic advantage to the industry," Blackburn said. "We want to communicate with the association and farmers to help develop ways to make maintaining genetic diversity more economically viable."

The same concern fuels the American Livestock Breeds Conservancy (ALBC), a non-profit organization in North Carolina working to protect more than 100 endangered breeds of cattle, sheep, goats, horses and poultry.

"Rare breeds aren't going to replace the traditional breeds in the mainstream marketplace, but an interest in the sustainability of these breeds has exploded in the last five years, thus creating a stronger market for the farmer," said Don Bixby, executive director of the ALBC.

It's the position of the Conservancy that the breeds most popular today will not meet the needs of the consuming public in the future, in part because of the rejection of the gene pool that takes place in selective breeding. Bixby considers his organization an employment agency of sorts for rare breeds.

"A breed will not survive if it does not have a place in the farmer's economic survival," he said. "It sounds harsh, but for rare breeds to survive, they need to be eaten."

The Conservancy is not the only place working to educate the consuming public about the aesthetic, economic and genetic value of rare domestic animals. Many state parks and private institutions around the country have programs in place to demonstrate the use of these animals in educational, economic and historical terms.

In fact, living history might be synonymous with preserving diverse genetics. More than 225 institutions are members of the Association of Living History Farms and Museums, each of which incorporates rare breeds in its programming.

Regional sites include the Living History Farm in Des Moines, Iowa, Missouri Town 1855 at Blue Springs, Mo., and Watkins Woolen Mill State Historic Site in Excelsior Springs, Mo. These sites have a variety of rare breeds.

Watkins Mill is the only state-owned facility in Missouri with rare breeds. The site currently has a flock of about 15 Cotswald sheep. The flock is bred using stud services provided by Ruth Campbell, a farmer in Russellville, Mo.

State and private facilities are one market from which producers of rare breeds can sometimes draw income. In Texas, the Barrington Living History Farm at Washington-on-the-Brazos State Historical Site, raises, breeds and studies Ossabaw Island hogs, Pineywoods cattle and Dominique chickens, all on the ALBC's critical list.

"Our livestock is certainly a drawing point for tourists who seem quite interested in the concept of endangered livestock," said Don Barker, lead agriculture interpreter at the park.

In Richmond, Va., the Children's Farm at Maymont has Scotch Highland and Dutch Belted Cattle--both on the critical list of the ALBC. When the program began in 1982, the people at Maymont hoped to breed and also exhibit these animals. But they soon learned what many farmers learned--propagation of rare breeds is expensive and challenging. Breeding is no longer a part of the endangered livestock program at Maymont.

"It can be quite difficult to find a suitable studbook-registered dam or sire, and even harder to persuade the owner to allow it to travel for those services," said Shannon Wyatt, assistant director of the nature center and its animals. "It became cost prohibitive to continue our breeding program."

Ruth Campbell doesn't allow her sires to travel, mostly for fear of disease, infection and other health risks. However, she believes there is money to be made in raising rare breeds.

Milking Devon cattle, one of the breeds on the Campbell farm, are one example. The ALBC estimates fewer than 2000 registered milking Devon remain in the world--a situation that creates a tight niche market for products from the limited Devon herd. In fact, Devon clotted cream is considered an English delicacy and specialty stores in Great Britain buy the cream Campbell produces in Missouri.

Even without such fine-tuned niche markets as specialty English cream, Campbell believes breeding and raising rare animals can be economically sound.

But if you're looking for quick money, she warns it won't happen. Like any niche market, the labor needed for production may be dwarfed by market research and networking.

Lamberson at MU is not optimistic about the long-term profitability of rare breeds in this part of the country. Yet, as he looks at the idealism and interests of the coming generation of animal specialists graduating from his school, he believes that reality may indeed be influenced by idealism.

Freelancer Diana Lambdin Meyer and MU information specialist Jason Jenkins contributed to this story.