Animal control did nothing? That horse is being abused. I would go to a supervisor. Are the pens clean ? Water clean and available 24/7? If not try Code Commission.
I have mulitple aged horses, they are very expensive to feed. Some look better than others, a couple look thin, a bit ribby but being fed hay, on pasture for the ones that still have top and bottom teeth and no eye issues, sr feed, a+m for the ones that have dental problems could use some horsie dentures ;) , so unless a young horse has medical issues there is no excuse for it being skinny bony.
Authorities around here no longer investigate animal neglect. They do not have the money or resources to seize or care for the animals, so they just tell people outright that unless it is clearly a case that would result in felony charges and prison time, they can no longer afford to get involved. The rescues are full, private funds are not available and public taxpayer money has run out. Hay and feed are 3X to 4X higher than 2 years ago and their budget will not let them do anything. They would have to seize, feed and care for the animals involved and they cannot do it.
They will tell you that you can offer all of the help and feed you want to someone. You can offer to take the animals off of their hands. But, you cannot force anyone to accept your help or suggestions and you cannot trespass if they do not want you there.
Well - he is very thin. I am curious though as to why his coat shines? The shine typically goes prior to the weight loss.
As far as the no hay in the stall - after they finish eating - there usually isn't. Not defending anyone - simply stating a fact.
Well, I looks like he doesn't have a coat shine, that different than simply the camera catching the light shining through the stall, that just mother nature and hard science, and the hay really should have enough for a stalled horse to graze on all day since horses stomachs are made to be constantly eating.
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But anyway, to the original poster, I would suggest this;
Get your camera set to time stamp your photos, all simple compact camera have it, if you don't know how and don't have the camera manual, just Google "how to set a time stamp on a [insert camera model and brand here]" it should come up.
1. Take a picture with the time stamp
2. Then take series of photos over time and print them as evidence that they are not getting rehabilitated, this is solid proof because that time stamp on a camera usually is saved in the photos digital profile and can't be replicated so even if someone claims you put it on yourself, bring along a portable drive, sometimes called a thumb drive, a memory stick... idk what you call it but here's one:
Save the pictures from your computer on them, so wherever you are showing these photos you can access the digital ones and put it in the computer and right click the photo to show properties, and it should be saved in the properties and that is not able to be edited. (NOTE: this will only work if your camera is set to the correct date itself) I would Google that as well if you can't figure it out.
3. Contact a ASPCA, HSUS, or any local rescue, show them the photos, emailed or in person, both will show the time stamp directly on the photo.
Then you will have proof they are not caring for these animals. Make sure to showcase the same animals over so they can't say they are different animals!