Bald Spot Above Bum, Any Ideas?

[HankBruce]

Hi so over the last week I've been noticing one of my guinea pigs shedding more than usual, I thought nothing of it at first but today I noticed this flaky bald patch above his bum, I was reading online for things it could be and saw a few different answers so wasn't sure how to help it, so I thought I'd post some photos to see if anyone one has any specific answer for what this is and how to help my little guy .
Does anyone know what this is and how to treat it?
Thankyou c:

 

[Wiebke]

Hi so over the last week I've been noticing one of my guinea pigs shedding more than usual, I thought nothing of it at first but today I noticed this flaky bald patch above his bum, I was reading online for things it could be and saw a few different answers so wasn't sure how to help it, so I thought I'd post some photos to see if anyone one has any specific answer for what this is and how to help my little guyView attachment 81354 View attachment 81355 .
Does anyone know what this is and how to treat it?
Thankyou c:

Hi! Please have your guinea pig vet checked. It could be a fungal infection.
Please be aware that we are legally not allowed (as any public online place) nor qualified enough to replace a hands-on vet examination. What we can do is give you avenues to pursue with a vet to get the most out of a visit.