Guinea Pigs
Disease Conditions (cont'd)
External Parasites (Lice and Mites)
Lice and mites are the most common external parasites of guinea pigs. Lice are tiny, wingless, flattened insects that live within the hair coats of infested animals. Both adults and eggs are found attached to hair shafts of affected pets.
Mites are microscopic, spider-like organisms that infest the top layers of the skin in affected animals. Guinea pig lice and mites are not known to parasitize man.

Mite infestations are usually more severe than lice. A specific mite, Trixacarus cavie, causes serious infestations in pet guinea pigs. This sarcoptic mite lives in the outer layers of skin causing an intense itching and scratching with considerable hair loss. In some cases, they present without the itch and scratching, but only hair loss and crusting of the skin. In other cases, the infestation and irritation is so severe that the pet causes significant self-inflicted wounds and exhibits wild running and circling behavior.

A veterinarian can diagnose this mite infestation by performing skin scrapings of affected areas and viewing them under the microscope. Successful treatment consists of one to four injections of a specific antiparasitic drug at approximately two week intervals. In the meantime, if wood shavings are used as bedding or litter, it should be replaced with paper toweling to make your pet more comfortable.

Transmission of Trixacarus cavie mites can occur only through direct contact between infested and non-infested guinea pigs. Therefore, pet guinea pigs are not likely to harbor this parasite unless they are recent additions or had previous exposure to mite-infested guinea pigs. For your pet’s sake, be sure that any guinea pig he/she comes in contact with is healthy and free of this and other parasites.

Lice infestations often go unnoticed. However, heavy infestations are usually accompanied with excessive itching, scratching and some hair loss. Scabbing on or around the ears may also be evident. Guineas pigs have two types of biting lice that may parasitize them. Both irritate and abrade the skin’s surface and feed off the bodily fluids that exude through the superficial wounds they create.

A veterinarian can confirm the diagnosis of lice infestation by examination of the hair coat as well as microscopic examination of hairs from affected animals. Treatment is usually in the form of an insecticidal shampoo, which is prescribed by the veterinarian.

As with mites, lice transmission occurs through direct contact with infested guinea pigs. Therefore, pet guinea pigs are not likely to have this parasite unless they had previous exposure to lice-infested guinea pigs. For your pet’s sake, be sure that any guinea pig he/she comes in contact with is healthy and free of this and other parasites.

Guinea Pig Sensitivity to Certain Antibiotics
Guinea pigs are very sensitive to certain classes of antibiotics. For this reason, NEVER attempt treatment of your pet guinea pig at home without prior consultation with a veterinarian. Many antibiotics that are safe for other animals have been shown to be lethal to guinea pigs, whether given orally or by injection. In addition, even some topical antibiotics can produce serious detrimental results.

A partial list of potentially harmful antibiotics includes: ampicillin, penicillin, bacitracin, gentamicin, erythromycin, lincomycin, clindamycin, streptomycin, vancomycin and sometimes tetracyclines. Even if an antibiotic is not on this list, it does not ensure that it is safe to use. When improperly administered, any antibiotic can produce detrimental and often lethal results.

The primary mechanism behind this often lethal effect is a dramatic alteration of the normal microbial balance in the gastrointestinal tract. In addition to affecting the disease-causing bacteria in the body, they also interfere with the normal beneficial bacteria in the guinea pig’s digestive system. Guinea pigs have very delicate digestive systems, so any alteration can produce a cascade of events leading to serious illness or death. As well as causing disruption of the bacterial balance, these alterations also result in the production of harmful chemicals in the guinea pig’s body. Other antibiotics cause direct toxic effects to the guinea pig without initially disrupting the digestive system, often proving rapidly fatal.

Whenever a veterinarian prescribes any antibiotic, always supplement the guinea pig with about one-half teaspoon (2.5 cc) of plain yogurt twice daily. This therapy should continue for a couple days past the antibiotic therapy. Yogurt helps augment and replace the beneficial intestinal bacteria that are compromised by the antibiotic treatment.

The bottom line is never attempt treatment at home without first consulting with your veterinarian.

Special thanks to Drs. Harkness and Wagner, Drs. Rosskopf and Woerpel, Dr. Larry Peters and Dr. Lynn Anderson whose published information on this subject was compiled to produce this writing.
© 2004 Midwest Bird and Exotic Animal Hospital