Hope after you read this you don't end up with a beloved tame lost

If you are going through the swamp with a tame, stop once and a while to get on land and check for leeches on your tame. Go into creature settings and if you see 'remove leech' click it. Keep checking until the botton doesn't show up, as a single tame can have multiple leechs.

(Not related to leechs but I once saw like, 6 Rynionothas flying around absolutely DELETEING every creature in sight. Me, my parasaur, and my three raptors barely made it out with our lives.)

If you have a leech, campfires will burn it off. I THINK that fire might get leechs off tames too, but the first leech method I mentioned is waaaayyyyyyy less risky (Rip 5 dilos)

I hope this reaches you well, and have a wonderful day!

-Someone who is being chased by 6 Rynionothas