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New piggy problems: URI - ringworm - skin parasites

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Staff member
Mar 10, 2009
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Coventry UK
Most common infectious illnesses in new shop or breeder guinea pigs
The immune system in baby guinea pigs is still under construction when they are ripped away from the families, have their lives upturned several times and are kept at very close quarters in shops, especially in the holding area behind the shop front. Weak immune system, stress, close proximity and exposure are the ideal conditions for bugs to be picked up and spread around.
The only place you can avoid this is by adopting from a good standard guinea pig rescue with a mandatory quarantine, a pregnancy watch for all incoming sows and a health check before any guinea pigs are being put up for adoptions. Since many sows coming into rescue are pregnant, there are often babies to be found in rescue, too. We can provide lists for recommended safe rescues in several countries if wished.

We strongly recommend to see a vet for a diagnosis and appropriate vet strength products. Please do not home treat on spec with low dosed broad spectrum pet shop products that can only at the best temporarily suppress but not cure an acute outbreak. It is overall cheaper and quicker to do it properly once instead of starting a long running saga that is hard (and potentially deadly) on your piggies and frustrating for you. Some corners are simply not worth cutting!

Ringworm (fungal skin infection)
Highly infectious and transmittable to humans and other pets. Requires scrupulous hygiene and a vet strength disinfectant. Please see a vet promptly and ask for a preferably oral systemic fungal treatment, which is prescription-only. If not available, ask for an efficient dip.

Typically first noticed as little crusty, bloody or bald patches on the head and ears. In later stages patches can appear all over the body as they are spread around by shed ringworm spores.
If ringworm has been diagnosed, please follow the hygiene tips in our guide in order to get on top it once and for all.
Ringworm: Hygiene And Pictures

Do not cream; it will not prevent ringworm from spreading further as you do not reach the affected area around the bald spot, catch all spores and prevent other areas from getting infected!
Never treat skin problems on spec before seeing a vet. It is the same as wiping a crime scene. Your vet will be grateful if you leave them plenty of evidence for an informed diagnosis and allow them to start immediately with good quality treatment.

Respiratory tract infection (URI)
Respiratory infections in guinea pigs are bacterial and NOT viral like human flu. They require a full course of antibiotics.
If not treated at all, wrongly or undertreated, URI can kill or cause permanent damage.
See a vet promptly; the sooner treatment kicks in, the greater the chances of a smooth and quick recovery!

Typical symptoms in order of development: very frequent and persistent sneezing (much more than 5 times a day or a one-off sneezing fit), crackly breathing, yellow/greenish gunky eyes, coughing, loss of appetite, apathy.
Guinea Lynx :: URI

Any piggy that is lethargic and not eating much or not at all is a life and death emergency and needs to see a vet ASAP at any time fo the day or night! Please make a vet appointment first (if possible) before opening a support thread in our Health/Illness section.
Step in with syringe feeding fibre and water as soon as you notice your piggy not being quite well. Over 80% of the food intake is unlimited hay, so nibbling on a leaf of lettuce is just not enough to keep a piggy alive! The need to breathe comes before the need to drink and only thirdly the need to eat.
A guinea pig that is struggling to breathe will have no appetite and grow weak very quickly. The guts will slow down and then close down. Feeding lukewarm water doesn't contain any calories and won't save a guinea pig that has stopped eating! Your care is vital to keep your piggy alive until the antibiotic is kicking in, breathing has freed up and the appetite has come back. This can take several days.
Not Eating, Weight Loss And The Importance Of Syringe Feeding Fibre
Complete Syringe Feeding Guide

Persistent sneezing without any other more advanced symptoms developing can be caused by hay dust, pollen allergy, dusty bedding (please no pine shavings!), dry air from air conditioning or radiator heat, perfumes from air fresheners, scented human body care products and perfumes as well as scent sticks. Please never smoke in a room with guinea pigs! Allergies and sensitivities can only be diagnosed by default after a URI has been exlcuded by a vet.

Please never place shop guinea pigs in an unprotected and unheated outdoors hutch during the time frosts can happen. Guinea pigs need to be treated like tender plants!
They need to spend the winter months especially in frost areas under cover and with extra protection.
URI can result if your guinea pigs are exposed to wide temperature swings without being acclimatised.

Guinea pig specific parasites

Mange mites

(trixacarus caviae: invisible mites burrowing their eggs in the skin)
Mange mites will kill slowly and agonisingly if left untreated or undertreated!

Mange mites typically appear in the small of the back as a v-shaped bald patch but they can manifest in other parts of the body, too. Very intense, frequent scratching and biting of the skin; real discomfort/refusal to being held; fitting in advanced stages.
Please note that not all fungal infections and mites manifest in textbook form and that they can look very similar in the early stages, especially if they do not happen in a classic place.

Please disinfect the cage and any contents with a vet-grade disinfectant. Change the hay supply.
No guinea pig skin parasite can survive on humans. They are species specific. Mange mites can in rare cases affect humans shortly.

Please do not treat on spec with low dosed shop products that will only suppress the symptoms temporarily but won't cure. See a vet for a diagnosis and a good quality ivermectin or selamectin-based treatment; it requires at least 3 applications at the product specific interval to make sure that they are not coming back.

Hay/fur mites

(chirodiscoides caviae: invisible mites that fix their tiny egg cases to the hairs first around the back end but in advanced cases all over the body).
Eventually small bald or scurfy patches on the body if present for a longer time. The least harmful of the three species specific skin parasites that guinea pigs have.

Hay mites usually arrive in hay bags. They have become much more common in recent years due to imported branded hay from abroad. Please get rid of any hay, disinfect the cage and hard furnishings and wash any fabrics at a higher temperature (60 C/ 140 F).

The visible egg cases look like somebody has turned a pepper mill over the back end of your guinea pig; the eggs are tiny nodules like beads strung up on a hair if you feel for them. Always check the deeper layers of the hairs at the bum end for hay mite eggs during the regular weekly health check and weigh-in.
Treatment is the same as for mange mites. With major infestations it can be helpful to give your piggy a very short haircut or shave to remove as many eggs as possible mechanically; the hairs will grow back even in short haired guinea pigs. Throw away the hay (which they usually come in) and disinfect the cage with a vet strength deep cleaning product.

In very persistent cases, a two-pronged approach with ivermectin and a course of medicated lice shampoo can help. Please ask your vet for a suitable product. Lice'n'easy shampoo from Gorgeous Guineas may also help but is not necessarily able to clean out an infestation on its own.

Guinea pig lice are small pale things crawling around the coat. They live off the blood of guinea pigs. Treatment is with a vet strength ivermectin/selamectin product. Untreated lice in weakened guinea pigs can kill!

Lice are occasionally found in backyard/farm breeder piggies that are not receiving any vet care. Please be aware that any breeder piggies with bald patches need to see a vet for treatment promptly (parasitic and/or fungal). Healthy guinea pigs only have symmetrical bald patches behind the ears!

Guinea pigs don't have fleas and should not be treated for fleas.
Fleas And Flea Powders

More information on guinea pig parasites via this link here: Guinea Lynx :: Parasites
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