The stuff below is just what happens at Premarin farms for those of you that don't already know, or that aren't sure.
PMU (pregnant mares' urine)
What happens to PMU mares?
For approximately six months from fall through spring, the pregnant mares live in the "pee barns," forced to stand in stalls with urine collection devices strapped to them. The stalls are deliberately narrow to prevent pregnant mares from turning around and detaching the collection cups. In the last month of their eleven-month pregnancy, the mares are put out to pasture to have their foals. The mares are put in a herd with a stallion, so they quickly become pregnant again. In September, their foals are taken away from them to be sold, whether or not they are fully weaned. The next month, they're back in the barns and the cycle starts again.
The organization that represents the interests of the PMU ranchers, the North American Equine Ranching Information Council (NAERIC ), considers it "a testament to her health and strength" if a mare can have a foal each year for 20 years. Currently, approximately 7,000 PMU mares live on 73 contracted ranches in Manitoba, Canada. The minimum stall width specified in the regulations* -- even for the largest draft breeds so commonly used -- is a mere five feet. A typical PMU ranch consists of a small family and one hired ranch hand responsible for feeding, cleaning and exercising nearly 100 pregnant mares at a time.
All the mares stay in a rectangle stal from there chess to there rear end and or flanks.
This doesn't say anything about what happens to the foals. Most of the time, the colts are sold to people and sometimes slaughter houses. Depending on the filly's size, they will either keep them as a breeding mare like their mom or they will put it up for auction...
So... post those pics! Here is mine! His name is Dozer, he is six, and measures up to 18.2hh.