Alexis Madrigal in The Atlantic (article is a few months old but interesting):
While there are more than 8 million Holstein dairy cows in the United States, there is exactly one bull that has been scientifically calculated to be the very best in the land. He goes by the name of Badger-Bluff Fanny Freddie.
Already, Badger-Bluff Fanny Freddie has 346 daughters who are on the books and thousands more that will be added to his progeny count when they start producing milk. This is quite a career for a young animal: He was only born in 2004.
There is a reason, of course, that the semen that Badger-Bluff Fanny Freddie produces has become such a hot commodity in what one artificial-insemination company calls “today's fast paced cattle semen market.” In January of 2009, before he had a single daughter producing milk, the United States Department of Agriculture took a look at his lineage and more than 50,000 markers on his genome and declared him the best bull in the land. And, three years and 346 milk- and data-providing daughters later, it turns out that they were right.
“When Freddie [as he is known] had no daughter records our equations predicted from his DNA that he would be the best bull,” USDA research geneticist Paul VanRaden emailed me with a detectable hint of pride. “Now he is the best progeny tested bull (as predicted).”
Data-driven predictions are responsible for a massive transformation of America's dairy cows. While other industries are just catching on to this whole “big data” thing, the animal sciences — and dairy breeding in particular — have been using large amounts of data since long before VanRaden was calculating the outsized genetic impact of the most sought-after bulls with a pencil and paper in the 1980s.