Farmers have quadrupled how much milk a typical cow can make, but there are hidden downsides.
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.
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.
That’s a crazy number, but here’s an even crazier one: Despite the lethal mutation, using Chief’s sperm instead of an average bull’s still led to $30 billion dollars in increased milk production over the past 35 years. That’s how much a single bull could affect the industry.
Chief embodies the power and the perils of selective breeding