It's that baby hog again, and a couple of mysteries

I saw the baby hedgehog and brought him inside quickly so I could see if he was the same hedgehog and also to see what his condition was like.

He's a lively little fellow and definitely the same baby hog that I've been calling Itchy. I'm glad to report that the spines have been growing back on his bald patches, although his face still looks like it could do with some more fur.

Earlier in the evening when I was putting the hedgehogs' food out and cleaning out the feeding station, I discovered a whole load of these:

Hedgehog spines. I've never previously seen any loose spines like this. Does anyone know if hedgehogs naturally shed their spines? I wondered if perhaps there'd been a bit of an altercation between two hogs in the feeding station, although there was no blood. I also think the spines were too long to have been the baby's.

Later in the night, I observed - or rather heard - something else mysterious. I was letting Elsa in, and I heard this rather loud noise. I can only describe it as a "gurgling" - a bit like a prolonged tummy rumble. It was coming from a large-ish adult hedgehog who was eating from the bowl on the patio. I've never heard a hedgehog make a sound like that before. Does anyone know if this is normal? Are hedgehogs known to gurgle?