Yes, there are various historical reports of people eating animal feces with successful health benefits, but I see that wikipedia says it's likely a myth. It's something that I and many others have considered due to desperation and no better options. Some people have even tried it with success.
Human-to-human FMT is already a huge black box, and animal-to-human is even more so. There are hundreds of FMT human studies but none that I know of from animals to humans. I think it's harder to screen an animal for health & microbiome status than it is a human. Animals can more easily pick up a pathogen given their natural behavior of licking things and eating off the ground. Most animals have much shorter lives than humans. Perhaps the pathogens they pick up contribute to this, and perhaps it's something that can be passed on to humans.
There was an anecdote about the Hadza eating raw animal colon, and thus essentially doing FMT from animals:
Podcast EP 307 – Jeff Leach (Microbiome Expert / Anthropologist)
https://chrisryanphd.com/307-jeff-leach-microbiome-expert-anthropologist/
37:00 - talks about the hadza eating the colon & stomach of an impala raw.
Jeff Leach also covers this in one of his blogs:
https://web.archive.org/web/20160605005649/http://humanfoodproject.com/please-pass-microbes
But the Hadza have pathogens and doing FMT from them doesn't have a great track record.
Jeff Leach did it without reported benefits, and
another patient did it resulting in long-term detriments.
Overall I would say that it has the potential for benefit but seems much more risky.
