We can blame females for adding to the ills of dairy farmers. Turns out because the X chromosone weighs more than the Y, bull sperm can be fairly reliably separated into male and female. So, inseminate your cows with sperm with the X chromosone, you'll very likely have female calves. And when the calf matures and is bred, you'll have another milk producer, which is just what dairy farmers need in an era of over-production and low prices.
The NYTimes article (click on title) says the sperm-weighing process became available in 2006, so the impact is just hitting.
(I note one of the dairymen quoted in the piece sounds Dutch--the Dutch have been migrating to the US for our cheaper land.)