Ulrike sent me this email, and since I like exotic pets I thought I'd jump in with my opinion....
My
oldest girl (6yo) started to lose fur on her behind, creeping up
her back too. Looked like a typical mite infestation; skin flakes
coming off, some scabby bits where she had scratched/bitten and
made it bleed. So off to the vet we went.
He agreed that it looked like mites, but was a bit puzzled that he could not see any (took some hairs and flakes and put them under the microscope). Gave an injection just in case. Ten days were over, went to get the second shot, at this point there was no improvement yet. When almost a week later the shot had not shown any effect either, we went back.
Vet says it does not look like fungal as the hair loss is too irregular and he would expect patches or circles with fungal, however as it was not responding to the injections we should try something else.
Mabel is now (as of three days ago) on 0.4ml Septrin twice a day (he reckons as it tastes of banana piggies like it better than Baytril?) just in case it is something bacterial, and twice a week I bathe her with 1ml Imaverol diluted with 50ml warm water in case it is fungal. I really hope this will sort it out...
On another forum someone was putting up the query of hormonal issues, but I don't know... when pigs have lost hair in the past (for example my girl Milka who had a tumour on her kidney) the hair simply fell out as opposed to the whole flaky/scabby business.
He agreed that it looked like mites, but was a bit puzzled that he could not see any (took some hairs and flakes and put them under the microscope). Gave an injection just in case. Ten days were over, went to get the second shot, at this point there was no improvement yet. When almost a week later the shot had not shown any effect either, we went back.
Vet says it does not look like fungal as the hair loss is too irregular and he would expect patches or circles with fungal, however as it was not responding to the injections we should try something else.
Mabel is now (as of three days ago) on 0.4ml Septrin twice a day (he reckons as it tastes of banana piggies like it better than Baytril?) just in case it is something bacterial, and twice a week I bathe her with 1ml Imaverol diluted with 50ml warm water in case it is fungal. I really hope this will sort it out...
On another forum someone was putting up the query of hormonal issues, but I don't know... when pigs have lost hair in the past (for example my girl Milka who had a tumour on her kidney) the hair simply fell out as opposed to the whole flaky/scabby business.
In my experience the huge majority of skin issues in guinea pigs falls into two categories: mites and fungal. It's uncommon for me to see flaking skin and hair loss without it being one of these disorders.
Skin mites in these pets will always cause itching, sometimes severe enough to lead to seizures. It's actually very common NOT to find the mites, as it only takes a few to cause a significant issue. I also think that a light skin scraping should be done, not just plucking hairs (though this is not inappropriate). Because of the nature of this disorder, I will find mites in probably only at most half of the cases that I test. For this reason I often treat based on symptoms, using ivermectin injections spaced 10-14 days apart. If it's mites you should see improvement (though not resolution) within the first week, then likely a cure after the second injection. If it's not mites, then ivermectin won't do anything. This is what we call "response to therapy" and is an appropriate diagnostic tool.
Ringworm is the other big concern, and is very common in guinea pigs (I see it several times each month). Instead of being a worm, it's actually a skin fungus, and doesn't always have the classic "ring" shape. It also may not look like it does in dogs and cats, often being irregular and causing thick scabs. As I've mentioned in an older blog, using a blacklight (UV light or "Wood's lamp") is not diagnostic at all in guinea pigs because the species of ringworm they get doesn't fluoresce. Even if they have it you won't get a "glow" (and honestly it's minimally diagnostic in dogs and cats so I don't normally use it in any species). The only way to diagnose ringworm in guinea pigs is doing a fungal culture where you collect hairs and put them on a culture medium. It can take 10-14 days to get a result, though most positives show up within the first week. In any case where I have any doubts at all about it being mites, I will recommend a fungal culture since it's inexpensive and easy.
The most common hormonal problems leading to hair loss in guinea pigs are related to the ovaries. In these cases you will see symmetrical hair loss over the flanks and sides with no itching, scabs, or flakes. Spaying them fixes this particular problem, but it's also not really harmful. Besides this cause, just about any metabolic disorder has the potential for causing bald areas.
I've never personally used Imaverol (enilconazole), though it is used for ringworm in dogs and horses. I tend to use miconazole lotions myself. Septrin is a sulfa antibiotic commonly used in exotic species and should be effective against most skin bacteria. Either of these treatments can take 2-3 weeks to show significant results.
If the current treatment doesn't help, I would consider finding someone in your area that is very experienced with or specializes in exotic pets. Though guinea pig skin cases are usually pretty straight-forward, you can get cases that stump even the best general practitioner.
