Help!

[Oreo1234]

I have 2 Peruvian guinea pigs who are 9 month old brothers.
I've started noticing that one of them is loosing weight even though he has been eating the same amount.Also he is loosing a lot of fur.
Does anyone know what it might be?
Thank you!

 

[piggl]

It could be some kind of mite or parasite. Guinea pigs have some bald patches but as you describe a lot of fur, there is a chance something else is going on.

Please get your piggie to a vet, it may be uncomfortable for your boy.
Especially if he is losing weight, how much has he lost and over what period.
Weight - Monitoring and Management

There is a bit about different skin issues in this thread (and an extra attachment about hair loss)
New Guinea Pig Problems: Sexing & Pregnancy; URI, Ringworm & Parasites; Vet Checks & Customer Rights
Guinea Lynx :: Hair Loss

 

[Piggies&buns]

Welcome to the forum.

I’m sorry to hear he is unwell.
Please have him seen by a vet for a diagnosis.

If your piggy has lost 50g or more then you must step in with syringe feeding a fibre rich recovery feed or mush his normal pellets with warm water and syringe the mix to him.. Weight loss of 50g or more means your piggy is no longer eating enough hay. Hay is 80% of the daily food intake and you cannot judge intake by eye. Syringe feeding will replace the lost hay intake and will help maintain weight and provide the essential fibre the gut needs.

The guides below explain this further.

Emergency and Crisis Care as well as Bridging Care until a Vet Appointment
Not Eating, Weight Loss And The Importance Of Syringe Feeding Fibre
All About Syringe Feeding and Medicating Guinea Pigs with Videos and Pictures

 

[Oreo1234]

It could be some kind of mite or parasite. Guinea pigs have some bald patches but as you describe a lot of fur, there is a chance something else is going on.

Please get your piggie to a vet, it may be uncomfortable for your boy.
Especially if he is losing weight, how much has he lost and over what period.
Weight - Monitoring and Management

There is a bit about different skin issues in this thread (and an extra attachment about hair loss)
New Guinea Pig Problems: Sexing & Pregnancy; URI, Ringworm & Parasites; Vet Checks & Customer Rights
Guinea Lynx :: Hair Loss

I also thought it could be to do with a mite or parasite.But wouldn't his brother also have them?
In about 10 days he has lost 80g
I have tried to separate them incase.But they aren't happy,so had to put them back with each other.

 

[Piggies&buns]

I also thought it could be to do with a mite or parasite.But wouldn't his brother also have them?
In about 10 days he has lost 80g
I have tried to separate them incase.But they aren't happy,so had to put them back with each other.

Not necessarily - if is perfectly possible for one piggy to get them and not the other, for example with mange mites, a working immune system can allow a piggy to fight them off. We also don’t know it is mites, so you do require a vet check.
With that weight loss, you definitely do need to step in with syringe feeding. Switch to daily weight checks and syringe feed as much as is necessary to stop the weight loss each day.
Please don’t separate them. There is no benefit in doing so. Separation causes stress which in turn can lower the immune system and make fighting any illness a little bit harder. Also, separating them for medical reasons does sometimes have the potential to ruin their bond meaning they refuse to live together going forward.