For $40 and the trauma of pulling 40 strands of your horse’s mane out, you can find out the top three breeds that may have contributed to his lineage somewhere down the line based on maximum likelihood estimation and a bunch of genetic principles I learned my sophomore year in college and have long since forgotten. This, as everyone has noted, is mostly done for mustangs, but now that I’ve done it I kind of want to send in my old horse Rube’s mane hairs and see what they say. (He’s very probably an Arab x QH but I know nothing about him other than he is in his mid-30s and has done everything from packing to barrel racing.)
I love mutts. Hybrid vigor is real. My dogs are wonderfully mixed-up creatures and I have no desire to find out their ancestry. But for some reason the mustang genetic testing at Texas A&M intrigued me. It’s cheap because it’s research and they present it that way, not as some boutique handout of guesses accompanied by fancy branding, and as a scientist I appreciate contributing to the literature. I’ll rip hairs out and indulge my curiosity for that.
Anyway, Henry. Henry is a mustang from the Triple B Herd Management Area (“HMA”) in eastern Nevada. He grew up in the wild and wasn’t gathered until he was six. For all we know, there could be baby Henries running around out there. It’s crazy to think about. His HMA is in a pretty harsh and desolate area of the Great Basin Desert, and like many other HMAs, is currently severely overpopulated. In February 2018, the BLM gathered more than 1200 horses from Triple B, and a couple dozen were euthanized due to body condition scores of three or less, i.e., they were emaciated and had a poor prognosis for recovery. I found woefully little information about the origins of the horses in the Triple B HMA, and therefore my guesses about my guy’s background are based on standing back and squinting at him, trying to remember the horse breed books I stared at for hours on end as a child. Percheron? Paso Fino? Andalusian? He’s short (14-14.1 hh) and stocky with feathered fetlocks. On the rare occasion he gets riled up, he arches his neck and prances like a PRE. But other than that nothing about him screams ‘athletic.’
Imagine my surprise at the results. We should apparently be show jumping, because breed #1 was Hanoverian, and #2 was Holsteiner, two very athletic warmbloods. (Incidentally, during my brief, teenage career in the jumpers, I was obsessed with these two breeds and remember doodling their brands in my high school notebooks.)
The third breed was something called an Argentinian Criollo. Bingo. This witherless animal looks just like my short, curvy beast except with about half the back length. (Seriously what’s going on with her hip it’s like a mile long?)
One statement that stood out to me in the explainer for the genetic testing was
The more breeds involved in a cross the lower the probability that a good result will be delivered.
Mustangs originated from Spanish stock, sure. But over generations new breeds and crossbreds were added into the mix when people released them or they escaped. What if at least one of every breed known to North America has been introduced at some point? What if half that number had been? This test would be worthless. It’s possible this test was worthless, based on the statement above.
Whatever the case, I believe these wild (feral, non-native) horses are something entirely different from the animals they started from, shaped by survival and selected by nature, not man. Which brings me back to where I started, believing that I own a mutt with sturdy legs, a good brain, and the ability to survive on weeds and dirt. But I should probably start jumping him soon just in case there really is some Hanoverian in there.