Ectoparasitic Skin Disease in Gerbils
Mite infestation is usually not a serious problem in gerbils, but treatment is necessary to prevent the infestation from becoming a torment to your gerbil. There are different types of mites that are capable of living on a gerbil. There are the non-bloodsucking demodex mites, which may irritate the gerbil just by sheer number, and bloodsucking mites, which can cause extreme irritation due to the bites, anemia due to blood loss. In addition, the excessive scratching can lead to lesions, opening the door to opportunistic bacteria infecting the skin.
If treated promptly, mite infestation need not become a serious health concern. Also, it can be prevented by practicing good hygiene and maintaining a clean living area for your gerbil.
Symptoms and Types
A mite infestation will sometimes be visible to the naked eye as white or dark specks of dust on the hair follicles, but not always. Other symptoms which may be more easily identifiable include:
- Frequent itching or scratching, especially on back and rump
- Rubbing against the cage wire
- Inflammed or reddish skin
- Rough and dry skin
- Dandruff-like or dirt-like dust on the skin
- Hair loss (alopecia)
Under normal conditions mites are present in small numbers and do not bother their host. However, their numbers can increase when a gerbil is stressed, has decreased immunity due to old age or other illnesses, and/or is unable to keep the numbers reduced by normal grooming.
Other causes that have been found are a proximity to birds, as some types of avian (bird) mites will cross over to gerbils. Avian mites may have been acquired while the gerbil was residing in the pet shop, or they can be acquired in the home environment. Some of the ways in which gerbils may catch avian mites are by living in a home in which pet birds also live; proximity to fowl of any kind (such as in homes with small farms); and when their cage is proximate to a window that is in turn close to an outdoor bird nest.
Mites can also come into your gerbil's environment through infested food or bedding materials. It is recommended that food be frozen before use to kill any mites (or other insects) that may be in the food, and clean bedding materials thoroughly before use.
You may be able to make an initial diagnosis by wrapping a clean, white paper towel around your gerbil for a few minutes and then looking at the paper for the presence of red or black “dust.” If possible, it will be useful to collect the mites in a jar or closed container so that you can take then to your veterinarian for a determination of the type of mite you are dealing with. In some cases, you will be able to see the mites moving through the fur or across the skin's surface when you part the fur.
Your veterinarian will take skin scrapings and hair samples from your gerbil for a microscopic examination. An infestation will be diagnosed by identifying the mites or eggs that are found to be residing on the skin or hair. The clinical symptoms that are observed may also help in making a diagnosis of ectoparasitic infestation.
As with other cases of ectoparasitic infestations, mite infestation is treated by topical application of antiparasitic mite-killing medicated dusts and sprays. The medication may be in the form of an injected solution, or it may be administered orally through drinking water. Treatment will be influenced by your gerbil's health status and age, and your veterinarian will advise you accordingly about the route of administration, and whether you need to make any other changes while your gerbil is recovering from the infestation. Choosing a medication on your own is not recommended, as some anti-parasite drugs can be toxic for a small animal.
Even if only one of your gerbils is found to be infested, you will need to treat all of your gerbils, and you will need to aggressively treat the surrounding environment in which your gerbil has been living. It is known that mites will lay eggs in the lining of plastic or glass tanks, so you will need to to remove the tank entirely, treating it for a few weeks to be sure that it is free of mites before using it again. All of the bedding material will need to be disposed of, and it is further recommended that the materials be sprayed with pesticides and bagged securely before disposal. The cage and/or tank should be cleaned with a safe disinfectant, and all of the food and water bowls cleaned thoroughly or replaced. Lastly, new bedding materials should be cleaned thoroughly before use.
Living and Management
Follow your veterinarian’s advice regarding the application of antiparasitic medicated dusts and sprays for your pet gerbil, making sure to continue the treatment for the recommended duration. Gerbils that are under stress are at increased risk of infestations, since it is the immune system that suffers under duress, and the immune system that keeps a check on the population of mites that are able to survive on the body at any given time (that is, a small amount of demodex mites are normal and live on almost all mammals, including humans). Therefore, it is important to keep these things in mind when making changes in the household that might make the gerbil feel stressed.
Mite infestation in gerbils can largely be prevented by maintaining good hygiene and cleanliness both inside and in the surrounding environment of your pet gerbil’s cage. Disinfecting the cages on a regular basis is also a good habit.
In addition, proper care and nutrition, avoiding stress to your pet gerbil, and keeping the cage separate from locations in which the gerbil might acquire the avian form of mite can all help to prevent mite infestation in your pet gerbil.
Because one of the potential sources for mites is the pet shop or previous home from which the gerbil came from, you may want to take steps to prevent new gerbils from spreading mites to your existing gerbils, or talk to your veterinarian about products that may be used to prevent mite infestation. At the least, you will need to observe your gerbils for any symptoms that would indicate the presence of mites.