Bubble? Mantle Collapse? Aquatic Snail HELP

[invisibility42]

I woke up this morning to find my large snail with a huge bubble made of air/flesh extending from outside its shell. He's still crawling around and climbing on the glass (and his siphon is not extended). I think this is mantle collapse or something similarly devastating. But before I euthanize him I want to make sure there's nothing else I can do. Please help!!

If I do need to put him down, what is the most humane method?
Thank you.

Pictures:

[crossless]

Here's about putting to sleep. petsnails.proboards.com/index.cgi?action=display&board=misc&thread=8770&page=1 It's for land snails, but I think with little modification there's good tips for aquatic species too.

Mostly size counts little example no one would crush huge snail or boil it because big foot surface etc.

I would put snail to sleep if health issues would affect to it's normal life like can't fit inside of shell, can't eat or poop properly, snail don't move as much as normally etc. If snail can't live normal life better then put it to sleep.

Hope that link gives you some idea what you can do.

[coyote]

I know little about aquatic snails, but in land snails mantle collapse does not cause a bubble like that.

What part of the body is the bubble on? If it's at the mouth, I would suspect swollen mouth or gut extrusion in a land snail. Both are untreatable and fatal. I lost 2 snails to swollen mouth and I had to euthanize both (by putting in the freezer for a day or 2).

If the bubble is located at some other part of the body, then I'm afraid I'm stumped as to what it could be.

I wish I had more helpful information for you. I hope that whatever it is, your snail recovers.

[lee2211]

Looks like gut extrusion to me.
I know how to put Goldfish to sleep, don't know if it would work in the same way.
I doubt putting it in the freezer'd be humane, as being out of the water for long can slowly suffocate them so I'm not sure.
Sorry

[crossless]

I think I would not take aquatic snail out of water I meant with little modification example freezing, put snail in water to freezer and let temperature change happen..

[coyote]

The temperature change needs to be as rapid as possible to prevent the snail from acclimating to the colder temperature (i.e., no intermediate time in the refrigerator prior to moving to the freezer).

[lee2211]

petsnails.proboards.com/index.cgi?board=pests&action=display&thread=7692
Link provided leads to a sticky thread on gut-extrusion. This thread is to continue there.
Thank you.