U R my hero!!! Go check out the extra long post I made under "How do I feed my horse" post # 46 -
https://www.backyardchickens.com/threads/what-do-i-need-to-feed-my-horse.1212463/page-5 - I soooo completely understand where you are coming from.
I am/have been a pony breeder. In the last several years, we've had not 1 but 2 genetic anomalies show up. They can be treated, but can be very expensive w/o guarantees of living after the surgeries OR returning to a useful life or even a quality life. I've removed the ponies that produced the issue(s) from our breeding pool (euthanized in couple of cases). It's been hard and it sure did "slam" our breeding program. It also makes me wonder how many other ponies out there may have these issues. Folks with plenty of cash to throw at a pony hobby may be able to deal with them, but folks on a shoestring budget, getting a pony bred for riding and driving for themselves and their children - may not be able to. It hurts my heart and I get so totally angry when someone mentions - just give it away or send it off to a rescue... What - so someone else can deal with the problem? Is that how my previous donations to various rescues were spent? I don't think so... I no longer donate to those rescue operations after doing some digging into how donated funds are being spent (spending $10,000 on a surgery for a cat just blows my mind!!)... And what gives - that all "rescuers/rescues" seem to feel it is there god-given right to talk down to everyone including the ones that are providing volunteer hours and/or funds that are taken from their own families??? I agree - I like the term - "crazy soup of life".
A cryptorchid stallion (1 testicle retained somewhere in the abdomen) can be VERY dangerous. The surgeries here in NC, even for a #400 pony are VERY cost prohibitive! Also, abdominal surgery on a horse (any size) is difficult and can be extremely hard on the equine - no guarantees of any kind. You may spend that $$ only to have them die anyway... Not where we need to put our funds at the moment. Equine and livestock vets do not agree on how retained testicles are passed down genetically. From the sire through a daughter to grand son or directly from the sire to a son or having to come from both parents... Now, a friend who does tons of research, has pointed out to me that they've linked cryptorchidism to nutrition aspects at a specific point in gestation... OI - but that doesn't explain how it showed up in 2 different bloodlines of un-related ponies - in different years on different feeding regimens.
And then I had a beautiful little stallion that I bought. I was so thrilled when his price dropped to a reasonable amount that I could afford! Then years later - 7 of the 11 foals he sired for us have presented with slipping/locking stifles - I bought 3 that I'd sold, back, for the same $$ I sold them for. Usually on the left side, some are affected on both sides. We've tried with many of these to treat them - thru diet, specific exercise & muscle building or lack of, stall rest, pasture rest/work etc. Vets experienced in this condition state that none of the ponies (& none of the adults) display the conformation that pre-disposes to this issue. So now what? They don't even agree which of 2 procedures would be best for any given pony (I have not had them all checked out). One of those is significantly lower cost than the other - but if you do one and it doesn't work (one is actually going in and cutting the locking ligament - then will no longer be able to lock their own stifle to sleep standing up; the other is "blistering" the ligament so that it physically shortens as the scar tissue builds) - you can't go in and do the other as you've already done one and it wouldn't work... Also, again, neither promises a return to a useful (riding/driving) or even quality/comfortable life. Iiiiii.... I've been told since this ordeal started that it doesn't hurt the pony/horse and that they are ok. I beg to differ. Even with ACV, Devil's Claw, and Turmeric I've not seen any real improvement. I know what it feels like when my own hips hitch and/or lock (that is what finally stopped my riding activities in 2012 - I couldn't handle the pain OR the fear that I couldn't respond/move if something happened while i was riding). I have lost sales when someone comes out to view a sale pony and then sees another pony dragging a locked leg around behind them.

In the past 2 yrs, I've watched as the devilish fun personality of the first pony (he's 8 yrs old this year - it started between 18m & 2ys of age) to be afflicted by this issue has changed. He's become sour & grumpy. He DOES look like he hurts during very humid weather. His posture has changed. I hurt for him. He does know how to unlock his own stifles (backing up is the best way) and you will see him stop/pause when he locks and then take a deliberate step back or two or three. When his stifle pops, he then continues forward to do whatever he may have been doing. Two weeks ago when another pony challenged him, he locked up, couldn't get out of the way and was bowled right off his feet... I cried. Especially for our little Cupid - he was to be a replacement stallion. I was so EXCITED when he arrived and I watched as he developed. He was castrated the spring after this issue started. He has been started in harness, but I wonder if his occasional "bouts" of stubbornness result from pain or the lack of ability to do what is asked. He's a smart fellow! He also hasn't taken to any little riders & while normally I'd push thru the attitude and have him learn - it's not been something we've pushed IN CASE the problem stems from his locking stifles... His full sister was a lot worse, his full brother is now 5yrs old and doesn't display the issue at all... However, he hasn't been started in harness or under saddle.
And then there's the move to this new property (moved the ponies in Jan 2015). Ever treated a herd of Shetland ponies for lice?? OMG... Never, ever in my life of being around horses have I ever had this come up. It's terrible... I haven't been able to eradicate it from our herds or this property... It takes a toll on me - physically, mentally and $$. It takes a toll on the ponies, too. The last 3 yrs have been an off balance time in our lives and it's been exceedingly difficult to swing that pendulum back our way.
So, yeah, I understand. AND certainly commiserate with you on what those irresponsible owners left you with and COMMEND you on how you are dealing with it. Hats off to you!!