Missing fur from possible squabble

[PottyForPiggies]

I went to check on my boys before going out to dancing today, and noticed that Junior had a little bit of fur missing from by his nose. My boys often chasey chasey and chatter, particularly when they've had a hutch clean as they did yesterday, but fur has never been pulled like this in over a year. Stewart was originally the submissive pig, as he was only 4 months when we adopted him. Now he's older and chunkier it has swapped over and he throws his weight around a bit.
Any suggestions or advice?

 

[Jerrybelly]

Oww poor Junior!

 

[PottyForPiggies]

I was very worried when I saw it, but they are still both as cheerful as normal Junior is quite docile anyway, preferring to chill out and sleep in something fleecy rather than potter about, so I'm not concerned about him hiding away.

 

[Wiebke]

Keep an eye out; it could develop into fungal! It's a classic place for it.

 

[PottyForPiggies]

He will be getting extra special attention from me, don't worry It is a little darker at the top part though, I can't tell what from though

Any advice to prevent it Wiebke?