I captured an anaconda using a large catfish and transported it into an enclosure with both land and water. Whilst experimenting with what it would eat I intentionally died to it a few times and was very amused to see that I could use my own dead body to produce snake skin. However the anaconda's segments kept glitching and separating from it, and I am now down to a 3 segment snake.

Unloading the chunk and even traveling to the nether have not fixed it.

Catching and releasing it with a large catfish seems to reload its model and fix it, thankfully!

Still a wacky and annoying visual glitch which you may want to look into though.

I will also note I have like 20+ other mods on, and any of those may be causing weird behavior.