Alopecia

Alopecia is defined as the partial or complete absence of hair from areas of the body where it normally grows. This can sometimes be seen in guinea pigs.
 

Alopecia can be areas of partial or total hair loss, or the hair may look thinner than in other parts on the body, the skin may also be red, flaky or sore where there is hair loss or thinning. Guinea pigs naturally have a small bald patch behind each ear and have no hair on their feet – this is normal and not a sign of alopecia.
 

Any guinea pig can be affected by alopecia, often those who are immunocompromised due to stress or an ongoing illness can have secondary hair loss. There are several main reasons for hair loss, including some of the following:

• Mites and lice: guinea pigs can pick these up from hay or bedding and it can cause excessive itching
• Ringworm: this is a fungal infection which is often seen as bald scabbing usually around the face and eyes
• Cystic ovarian disease: older female guinea pigs are prone to developing cysts on their ovaries and these can cause hair loss over the flank regions of the body
• Hyperthyroidism: guinea pigs are prone to an overactive thyroid and this can cause hair thinning and hair loss across the body
• Barbering: this is where other guinea pigs will chew each others fur and cause hair loss and balding

Your vet will want to rule out mites or a fungal infection. A skin scraping is usually performed to look for mites. This can be done conscious and shouldn’t be painful for the guinea pig.

With ovarian cysts other than alopecia on the abdomen, the vet will need to palpate (feel) the abdomen to detect the cysts. Your vet will want to do an ultrasound scan to look at the ovaries to confirm this; this can be done conscious. If cysts are present then spaying your guinea pig will be advisable as this will cure the problem. In a suspected case of hyperthyroidism your vet will need to take a blood sample to check the tyroid levels and the guinea pig may be started on oral medication to combat the overactive thyroid. If the problem is barbering then often providing more space and environmental enrichment for your guinea pig will help resolve this and sometimes it will resolve without intervention.

If left the cysts can rupture, which can prove fatal, so your vet will likely recommend spaying the guinea pig. This involves a general anaesthetic to remove the uterus and ovaries. This will be curative of the problem, but the risk of the anaesthetic needs to be considered prior to surgery.
 

If an underlying illness which is causing the alopcia is not treated correctly, then yes, it can be serious. In cases of behavioural barbering, then this is not a serious condition. You can prevent the risk of mites, lice and ringworm by ensuring that your guina pigs house is disinfected with a pet-friendly disinfectant at least once a week and the hay/bedding you buy for your guinea pig is clean and from a reputable source.