Producers breed better cows faster through genomic selection

Here’s the thing about bulls: they do not make milk. So when producers want to breed cows with better milk yield, it’s tricky to pick the right bulls for dads. Many breeders use a method called “progeny testing,” where a bull’s daughters are tested for milk production once they mature. But progeny testing takes money and time that many producers don’t have.

Today, as DNA sequencing becomes more affordable, many producers are turning toward a more efficient process known as  genomic selection.

In a paper published this month in Animal Frontiers, scientists explain how genomic selection can help dairy cow breeders. Genetic selection does not require producers to wait until an animal matures to determine whether it shows good traits, such as high milk yield. By analyzing the DNA of their animals, producers can identify animals with good traits as soon as they are born.

 “One reason this project is so exciting is because there is a ton of research on dairy genomics right now. This project makes people rethink the way they do everything,” said Kent Weigel, professor of dairy science at the University of Wisconsin, Madison and co-author of the Animal Frontiers paper.

Weigel said this new method could completely change how dairy cattle breeders do their work. Because producers can use DNA analysis to identify productive cattle, they can shorten the generation interval from six to seven years down to two to three years. That means more high quality cattle in a shorter period of time.

“There will be long- and short-term benefits of this new method of DNA analysis,” said Weigel. “Short term effects include the knowledge of which bulls have better genetics. There will be a greater availability of high-quality semen from good bulls. There will also be a better opportunity to identify top-quality females and integrate those superior traits throughout the cattle herd.”

According to Animal Frontiers, dairy genetics are being revolutionized worldwide by animal science professionals. Weigel said many studies are also being conducted in Europe, where scientists are designing new breeding programs using data simulation for optimum genetic success while keeping inbreeding in check.

The study was titled “Genomic selection in dairy cattle: Integration of DNA testing into breeding programs.” It can be read in full at http://animalfrontiers.org.

Media contact: Mae Council

mcouncil@purdue.edu/618-334-5779