The Dairy Industry Lost $420 Million From a Flaw in a Single Bull

It started with a bull named Pawnee Farm Arlinda Chief, who had a whopping 16,000 daughters. And 500,000 granddaughters and more than 2 million great-granddaughters. Today, in fact, his genes account for 14 percent of all DNA in Holstein cows, the most popular breed in the dairy industry. Chief—let’s call him Chief for brevity’s sake—was so popular because his daughters were fantastic milk producers. He had great genes for milk. But, geneticists now know, he also had a single copy of a deadly mutation that spread undetected through the Holstein cow population. The mutation caused some unborn calves to die in the womb. According to a recent estimate, this single mutation ended up causing more than 500,000 spontaneous abortions and costing the dairy industry $420 million in losses.