So I'm having an issue concerting some horses I'm working with. Rather, the issue is with their owners. The horses (two 6 year old, unbroken mares, about 15hh-15.2hh) are horribly overweight, to the point that I am concerned for their health. Even though it's cold and snowy here now (I'm in the Yukon), the extra weight is excessive. The horses are fed one square bale (about 50lbs) per day between the two of them (apparently they used to get a bale a day each!), as well as oats and some sort of compound pellet feed (I haven't seen any empty bags around so I'm not sure what's in it). They are not in any work right now, apart from basic ground work.
I've tried speaking with the owners about this, but they just sort of nod and smile and nothing changes. I've mentioned my concerns in regards to health AND the money they could be saving, but to no effect. They have never owned horses before and don't have much knowledge on horse keeping (although they DO mean well and everything, they lack the ability to carry out basic tasks such as haltering the horses safely), so I've tried to give them information including books but they just aren't receptive to it. At this point, I'm not sure what to do. I tend to be bit stringent about feeding, so it's hard for me to witness such careless abandon when it comes to severely overweight horses. That being said, horses are a bit like children in that everyone has their own way of doing things and I hate to interfere. They are, in essence, killing them with kindness.
Any ideas as to what I should do?