A (Genetic) Star is Born
Through advances in reproductive biology and DNA profiling, animal science researchers help cattle producers become economically successful.
At early light in the dead of winter, cattleman Gene Kinslow crunched across a sheet of snow to a corral, hundreds of feet from his valley home in Fordland, Missouri.
He was anxious. A calf might have been born that night. But it was bitterly cold with icy winds, and the corral was an open face to the elements.
When Kinslow arrived, the 60-pound newborn was standing on wobbly legs and nursing. Punishing weather? Not a problem for this hours-old animal. “It was a doer, aggressive, a vigorous calf,” Kinslow says. But that wasn’t the whole story. When the heifer’s DNA profile arrived in the mail a month later, Kinslow discovered he had a superstar.
Orella, born Feb. 26, 2015, is a 1-percenter. She possesses key traits prized by beef cattle producers that are better than 99 percent of the other calves registered with the American Angus Association, which has a registry in the millions. The calf was created at Kinslow’s Windmill Cattle Co. in the Ozarks in part through reproductive biology and selective breeding practices pioneered by researchers in the Division of Animal Sciences at the University of Missouri. Using fixed-time artificial insemination and other techniques taught by Dave Patterson, an MU Extension professor and reproductive specialist, Kinslow and son Andrew, a doctoral student at MU in science education, have improved the quality of their cattle herd.
Meanwhile, MU geneticists have helped make bovine DNA profiling, like that used by Windmill, possible. In December 2008, the genetics technology provider Illumina marketed a cattle genotyping chip developed by a team co-led by Jerry Taylor, Curators Professor of Genetics and Animal Science. A standard in the industry, the chip and its descendants are now used by breed associations and farmers nationwide and in at least 10 other countries.
MU Extension Professor Jared Decker, PhD ’12, crisscrosses Missouri teaching producers the economic advantages of genotyping beef cattle, which account for about 95 percent of the cattle in the state, or 1.9 million animals. “We take the science knowledge and bring it to the producers,” says Decker, an assistant professor in beef genetics. “Everything we do in animal science is with that goal in mind: to help producers become more sustainable, efficient and profitable.”
At a time when many university animal science divisions are cutting back, MU is adding top junior faculty like Decker, who started in 2013. Nationally recognized experts in the division include Taylor; Patterson; Randall S. Prather, Curators Professor of Reproductive Physiology and Molecular Biology; and Michael Smith, professor of reproductive physiology and winner of the 2015 Southeastern Conference’s Faculty Achievement Award.
Last year, the division welcomed distinguished scholar Thomas Spencer, who leads two grant-funded projects on increasing fertility in dairy and beef cattle. With a joint appointment in the School of Medicine, Spencer also translates animal fertility research to human health medicine to solve reproductive problems in women.
“The critical mass we have relative to economics, genetics and reproduction is something you don’t find at many colleges of agriculture and animal science divisions,” Patterson says.
Cattle typically are pretty docile. But when in heat, they act crazy. Butting heads. Kicking up dirt. Shaking their massive torsos like a dog shedding water. Many cattlemen watch cows for days for aberrant behavior, indicators that they are ready to be artificially inseminated. Indeed, inseminating cows with semen from a prized bull is becoming more common; Orella’s mother was inseminated from a top Tennessee bull. Progressive farmers also embrace the fixed-time approach. Thanks to advances in reproductive biology, cows can be bred at an exact moment — say, 8 a.m. Tuesday — early in the breeding season.
Fixed-time artificial insemination is taught across Missouri by facilitators of MU Extension’s Show-Me Select Replacement Heifer Program, which Patterson founded in 1997. The process saves time and money by doing in hours what used to take days or weeks, since farmers had to wait for each animal’s natural estrous cycle. Also, when cows are bred early in the season, the newborns have longer to grow and fatten. They fetch more at market than calves born later in the season. “The earlier the cows and heifers calve, the more pounds of beef you have and there’s more of a chance you can get them re-bred,” says Howard Early, who co-owns a row-crop and 400-head beef cattle farm in Warrensburg, Missouri. His operation has been enrolled in Show-Me Select since 1998.
Besides teaching reproductive biology, Show-Me Select selectively breeds cattle for traits such as ease of calving (so fewer cows and calves die during the birthing process), weaning weight and meat quality. Over the years, herd genetics get better as top cows and sires replace others. Mike Kasten runs a commercial 450-head cow-calf operation in Cape Girardeau, Missouri. The Show-Me Select participant says that after artificially inseminating three generations of cows from Angus bulls with superior genetics in marbling, the primary determiner of meat quality grade, the offspring were all Certified Angus Beef or USDA Prime.
Meanwhile, DNA genotyping has largely ended the guessing game of whether a cow or sire has the right stuff. Kinslow sent Orella’s blood sample to the American Angus Association’s genomic division for a 50k DNA profile. It cost him $75, a bargain given the alternative. To match the information provided in the profile, Orella would have had to give birth to 14 calves in 16 years (very old for a cow), and the traits of each progeny meticulously charted, Kinslow says. And what if Orella was genetically subpar?
“The real cost to a purebred breeder is not knowing for years which of your animals are actually genetically superior,” Kinslow says. “That amounts to lost time, huge unnecessary expense and slow genetic progress.”
Bovine Snip Chips
Breeding cattle for desirable traits began in England in the eighteenth century. But rather than select for the best-producing beef and dairy animals among the herds, cattlemen went Hollywood, selecting for looks: big horns, straight ears, solid coats. Form rather than function prevailed until the 1940s, when selecting for meat and dairy production gained traction.
In the 1960s and ’70s, cattle associations established databases on the pedigree, anatomy (such as pelvis measurements), and beef and dairy production of tens of thousands of livestock. Selection decisions focused on the quality and quantity of milk and meat.
But “when you select for only one thing, you always sacrifice something else,” Spencer says. A measurable decrease in fertility, especially in dairy cattle, and disease resistance were the results, he says.
Furthermore, predicting an animal’s genetic merit from database information was never perfect science. When speaking to producers about cow pedigree, for example, Taylor asks producers to acknowledge how dissimilar they are from blood relatives. For humans as for cattle, “you could get full brothers and full sisters who are awfully different from one another,” Taylor says.
Fortunately for cattlemen, animal scientists have discovered a better way.
The human genome was sequenced in 2001, followed eight years later by the sequencing of the cow genome. Over the years, genetic science progressed as researchers learned that a trait, such as blue eyes in humans or tender meat in cattle, was not the product of one gene but of many. In Angus, for instance, nearly 20 genes significantly influence marbling score, Taylor says. At the same time, the cost of DNA sequencing plummeted. In 2000, sequencing a million base pairs of DNA was $10,000; today it’s 10 cents. Better science and lower overhead set the stage eight years ago for the University of Missouri’s co-development of Illumina’s BovineSNP50 BeadChip, or snip chip.
The snip chip enables livestock genotype service providers and breed associations to make accurate genetic predictions on animals using nothing more than a DNA profile. It compares a bovine DNA sample with thousands of other bovine samples to predict the genetic merits of an animal for up to 17 economically important traits. Almost all bovine snip chips on the market today, including the one used by Kinslow, were based on MU’s co-design.
But genomic science is a restless beast, and breakthroughs tend to bump against each other. In January 2016, at the Plant and Animal Genome Conference in San Diego — the largest conference of its kind in the world — Taylor announced a new chip with far-reaching impact on the cattle industry. Its name is a mouthful: the GeneSeek Genomic Profiler Functional 250k BeadChip, or GGP F250. Three grants to MU and one led by Texas A&M from the USDA’s National Institute of Food and Agriculture helped finance its development.
Just as high-definition TVs offer better resolution than 1970s models with vacuum tubes, the 2008 snip chip offered more detail of the bovine genotype than its forerunners. But the F250 goes further. Imagine a satellite collecting images, but instead of capturing images of a valley farm, it zooms in on genes to record the structure or number of encoded proteins. The F250 gets to the nitty-gritty of genomic science.
The details are necessary to spot genes affecting livestock feed efficiency, disease resistance and fertility issues related to embryonic viability — traits hard to pinpoint without a zoomed-in view. Cattle deficient in these traits cost producers millions of dollars each year.
“The amount of data that we have generated to build this chip is easily 1,000 times more data than was used to build the 50k chip,” says Bob Schnabel, research associate professor in molecular biochemistry.
Curt Van Tassell, a USDA research geneticist and contributor to the F250 project, said the tool might help prevent many common genetic defects in beef cattle. “The availability of such a resource could provide a great opportunity for research and industry,” he says.
Don’t Be Left Behind
Orella has a long body, robust build and short, silky black hair. She resembles other black Angus, but with a difference, according to Kinslow, who sometimes pauses during the day to admire her in the corral. “She is structurally perfect,” he says.
But the Ozark Plateau is not Hollywood. Kinslow has little interest in throwback selective breeding for shiny coats and symmetrical builds; the cow will not be a contender for a Blue Ribbon at the Ozark Empire Fair in Springfield. In June 2016, Orella will be superovulated, placed in heat and artificially inseminated to a top bull. Days later, the resulting embryos will be flushed from the uterus and frozen to preserve her superior genetics, or immediately implanted in other cows. Eventually Orella will be put out to pasture and bred yearly.
As cows’ lives go, she will have a good one. “We take really good care of her,” Kinslow says.
The Missouri cattleman appreciates the science that both created and DNA-profiled Orella. Though cattle DNA profiling has been widely available since 2010, and experts gush over the technology, most cow-calf producers (90 percent, by some estimates) still don’t profile their livestock.
They are missing out, Kinslow said. “The business end of this is simple. If you are not using DNA profiles for cattle selection decisions, you are going to be left behind.”