Something yellow near my Guinea pigs butt

[LokiCat]

I have been noticing that my Guinea pig Loki has some yellow gunk and a bit of staning near his rear end it dosent seem to hurt him at all but it still worries me a bit. He also has loss of hair in that area. Is this something I should bring him to the vet for?

 

[LokiCat]

This is a better picture

 

[Wheekallweek]

That's his scent gland. Some coconut oil gently rubbed in may help to remove the build up of grease

 

[Piggies&buns]

That is his grease gland.
It may just be dirty and need a clean but sometimes they can become problematic/unhealthy and require vet care.
If you are at all worried that it is not healthy particularly if he is losing hair then do see a vet

Bathing (including cleaning grease glands)
Guinea pig body quirks - What is normal and what not?

 

[Wiebke]

This is a better picture

Hi

What you are dealing with is an overactive grease gland. The tiny scent gland sits in front of the genitalia on the bum side. Sows can also occasionally have an overactive grease gland but it is much more common in boars.

Please use coconut oil (available in supermarkets) for gently cleaning without drying out the skin around it.

For comparison pictures and other boar problems you will find these guide links here helpful:
Boar Care: Bits, Bums & Baths
Bathing (including cleaning grease glands)

 

[LokiCat]

Okay thank you!