I am putting these images here just for the sake of comparison.
I want to make it clear that I am not an expert on horses. I have owned one horse and one pony, years ago. I currently own two donkeys and some cattle.
In my opinion, this horse has lost weight. The first three images are from Nicole’s Blessed Little Homestead blog (look it up on Google, it’s the entry for October 23). If I link to it here, and you follow the link, she will block your IP address. In fact, she will probably block your IP address anyway, so if you know how to use a proxy, do so.
The last image is the one from today.
If this were my animal, I’d be finding out if her condition was okay by talking with some experienced horse people. I’d be checking to see if her hay was adequate (and I’d ask more than one person and certainly somebody other than the person I was buying the hay from). And I would make sure that her diet was adequate and her living conditions suitable.
I would do something to horse-proof that paddock.
I would not be in a panic, but in my experience, if an animal starts losing weight, you can get in big trouble really fast. They can lose weight rapidly, and take practically forever to put it back on. (I wish I knew the secret to that!)
Anyway, here they are for comparison and future reference.
All the above are from October 23.
NOTE: My thanks to the person who has the rights to those last two photos and who sent them directly to me.