BLUE TONGUE SKINKS

So vens just done a poop and urate and sperm plugs, but there was also a blob of yellowy mucus... if i didnt know he was a boy id say it was a slug because it looked like pictures ive seen of those in the past. Any ideas what it could be? Hes lively, eating normally etc. Will get a picture if it happens again, i cleaned it up before i thought to take a pic this time.

At times there is yellow in urates.

Yerh, he has yellow in his urate fairly often, have taken him to vets previously and all checks been okay, but this time it was a really big blob of yellowy quite firm mucus (sorry, gross) maybe hes just been a bit constipated?