To
the uninitiated, “the role of genomic estimated breeding values (gEBV)” sounds like a workshop you attend when you lose a bet. In fact, gEBVs hold the power to fashion a win-win for researchers and the commercial cattle business. That may explain why they’re a primary focus for the Genome Alberta project that’s applying genomics to improve carcass quality and feed efficiency in beef cattle.
“The advantages of using genomics or gEBV to evaluate an animal’s traits over the traditional genetic evaluation using EBVs are especially pronounced in traits that are hard to measure, sex limited, have low heritability or are expressed late in life,” said Dr. Mohammed Abo-Ismail, Postdoctoral Fellow with Livestock Gentec at the University of Alberta.
The need for feed
For example, the current Genome Alberta project targets feed efficiency, a trait that is difficult to improve through traditional genetic selection as it entails measuring individual feed intake.
“Such a measurement is time consuming, difficult and expensive, requiring sophisticated technology such as Insentec© or Growsafe© systems,” said Dr. Abo-Ismail.
“Using genomics, once the relationships between genetic markers and feed efficiency or other traits are determined, this prediction can be applied to genotyped animals without the need for phenotyping with costly feed intake measurements.”
As well, this project is generating predictions for carcass and meat quality traits. That presents a unique challenge, as measuring these traits requires animals to be killed, making progress through traditional evaluation very difficult. By contrast, genomic-based predictions are possible on live breeding candidates once producers are able to sample the animals – through blood or hair samples – for
genotyping.
The need for crossbreeds
Even cutting edge technology has its challenges though.
“The main difficulty we face is obtaining accurate gEBVs across breeds and for crossbred commercial cattle. Doing so requires a large number of animals as a reference or training population, and that’s no small feat.”
Fortunately, Dr. Abo-Ismail and his colleagues are up to the task. By the end of this project, they expect to have a reference population of 18000 animals assembled for genomic-based evaluations for the traits of interest.
That’s good news for industry, because gEBVs could be a producer’s best friend.
Nothing to beef about
“They (gEBVs) are important as they help producers select the best breeding candidates according to their breeding objectives, thereby increasing the genetic gain and boosting the producer’s net income in the process.”
And the good news doesn’t end there. According to Dr. Abo-Ismail, developing cost effective low density panels based on functional mutations from sequence data can increase the adoption of the genomic technology in the beef cattle industry.
“This means more data is going to be available to further improve the accuracy of gEBVs for even better genetic gain and net income for commercial cattle producers.”
Of course for those producers, groundbreaking research is wonderful, but their focus is geared more towards the practical: “show me the money”.
“The expected economic benefit of a selected bull based on gEBV will be between $335 and $690. Additional benefits include marketing advantages, feed and labor cost savings and increased efficiencies in animal management.”
The power of genomic prediction is already visible in the dairy industry. For example, using genomic selection in Holstein cattle has helped double the genetic gain for production traits and increase it
300-400% for low heritable traits.
“Although the beef cattle industry has some challenges due to the existence of multiple breeds, crossbreeding and natural mating, it is possible with the current resources in this project to provide accurate genomic predictions to increase the genetic gain in feed efficiency and carcass traits across the commercial beef industry.”
So maybe a talk on genomic estimated breeding values won’t have non-scientists lining up to attend. But if the technology matches the promise, it could soon be the hottest ticket in town.
