Common Mites of Your Rabbit and Small Animal - cumberland ...

Common Mites of Your Rabbit and Small Animal 

PART 1: FUR MITES 

Fur mites, or “walking dandruff,” affect mainly rabbits, 

but also guinea pigs, hedgehogs, rodents, cats, and dogs. 

Although an uncommon host for the mite, these mites 

can also be transmitted to humans. The mites are nonburrowing 

skin parasites. On close observation of an 

infested pet, movement of the dandruff is visible caused 

by the mites moving underneath the scales. There are 

different species of fur mites that cross over and infest all 

pets and others that are specific to certain animals. 

TYPES OF MITES 

There are three common species of Cheyletiella mites that 

affect cats, dogs, and rabbits. They are Cheyletiella yasguri, 

C. blakei, and C. parasitivorax. They are typically found 

on dogs, cats, and rabbits, respectively. Although each is 

more specific to a particular species, all three have the 

potential to cross over to other host species. 

A mite common only to laboratory colonies of guinea pigs 

is Chrodiscoides cavaie, also known as “static lice.” These 

mites firmly attach to the hindquarters and the “lice” are 

actually eggs. 

These mites are non-burrowing, living in the fur (pelage), 

and feed off of the keratin layer of the skin. Pale yellow 

to white, the mites cause skin irritation, usually along 

the back of the animal, caused by a digesting enzyme 

Cooperative Extension 

Deborah L. Cole, County 4-H Agent 

Jeannette Rea-Keywood, County 4-H Agent 

Mary Ann Metz, 4-H Program Assistant 

excreted by the mite. This enzyme partially dissolves the 

skin, letting the mite eat the dissolved skin and causes the 

irritation to the animal. 

The signs and treatment for all Cheyletiella mites and static 

lice are the same, so identifying the species is not relevant. 

These mites can also infest humans but are considered 

transient because they cannot complete their life cycle on 

humans. 

TRANSMISSION 

Direct contact with an infested animal is the most 

common way to pick up mites. Since the mites can 

also survive off a host for a few days to weeks in the 

environment, they can also be picked up through contact 

with bedding, toys, grooming equipment or other objects 

carrying the mites. 

LIFE CYCLE 

The life cycle of mites is about three weeks and takes place 

entirely on one host. A female adult mite will lay eggs on 

the host animal. The eggs hatch into larvae, developing 

into nymphs, and then into adults. 

An adult mite is very small, ranging from 0.3 mm to 0.5 

mm, with eight legs. Feeding off of the keratin layer of 

the skin and in order to digest the skin, the mites secrete 

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an enzyme that actually dissolves a small part of the 

skin. This is what causes the itchy, hair loss, scabs, and 

discomfort. 

SIGNS AND SYMPTOMS 

Visual signs include chronic dandruff, “walking 

dandruff,” chronic scratching of the hindquarters, nape of 

neck, and along the back, sores or scabs in the same areas, 

and hair loss. Microscopic diagnosis of the mites or eggs 

recovered by a skin scraping, combing, or acetate tape can 

positively identify an infestation. Affected skin may be 

slightly reddened, oily, hairless, and have scaly patches on 

the head, shoulders, and back. In rabbits, C. parasitivorax 

might not cause signs or it can result in loose hair pulled 

out in clumps. Hedgehogs have been known to lose quills 

C. cavaie may cause little signs or cause scratching, 

redness, hair loss, and flaking in guinea pigs. A rough 

hair coat and even skin ulcers can result from continuous 

grooming. 

TREATMENT 

Mites are transmitted by direct contact with the host, 

animal bedding, or hair and debris. Therefore, it is 

important to clean and treat the environment while 

treating the animal. Treat any animals in contact with the 

infested animal even if they are not showing any signs. 

Thoroughly clean and treat the areas where your pet 

sleeps and roams. This includes bedding, carpets, sofas, 

chairs and cushions, and stuffed toys. Make sure to 

vacuum carpets and cushions before treating to increase 

penetration of the dust or powder. Steam cleaning and 

shampooing is not recommended as this could create the 

type of conditions they prefer. Prior to any application, read 

and follow all directions making sure the product is safe for 

rabbits, cavies, or other small animals. 

Common recommended pesticides include lime sulfur 

dips, ivermectin or selamectin, permethrins, pyrethroids, 

and phenylpyrazoles . Phenylpyrazoles and permethrins 

should not be used for rabbits or cavies. Always consult 

with your veterinarian before beginning any treatment. 

Apply dusts and liquid topical treatments near the 

shoulder blades, back of neck, and on the rump. Prior 

to any application, read and follow all directions making sure 

the product is safe for rabbits, cavies, or other small animals. 

In unresponsive cases, injections of ivermectin are often 

used. In all cases, treatment will need to be repeated 

two to three times varying from five days to three weeks 

depending on the pesticides used. The adult mites are 

killed during the first treatment, but eggs that remain in 

the fur or the environment will hatch and the larvae will 

grow and lead to a new infection cycle. The follow up 

treatments will kill the later ones. 

The best practice is prevention of an infestation through 

consistently clean bedding, pens and cages, handwashing, 

and not sharing grooming equipment, toys, or 

bedding, regular grooming, and frequent health checks. 

References 

Jeromin, Alice. (2008, May). Cheyletiella mites: 

Population on the move. DVM In Focus, 20-24. 

Krempels, D., Ph. D. (2008). Fur loss and skin problems 

in rabbits: Common causes and treatments [on-line]. 

Available: http://www.bio.miami.edu/hare/furloss. 

html#furmite 

Percy, D.E. and Barthold, S.W. (2001). Pathology of 

Laboratory Rodents and Rabbits (2nd edition). Ames, 

Iowa: Iowa State University Press. 

Van Pragg, E., Maurer, A., and Saarony, T. (2010). Skin 

Diseases of Rabbits (First edition). MediRabbit.com 

White, SD; Bourdeau, PJ; Meredith, A. (2003). 

Dermatologic problems in guinea pigs. Compendium on 

Continuing Education for the Practicing Veterinarian, 25 

(9), 690-697. 

© 2012 Rutgers, The State University of New Jersey. All rights reserved. 

For a comprehensive list of our publications visit www.njaes.rutgers.edu February 2012 

Cooperating Agencies: Rutgers, The State University of New Jersey, U.S. Department of Agriculture, and County Boards of Chosen Freeholders. Rutgers Cooperative Extension, a unit of the 

Rutgers New Jersey Agricultural Experiment Station, is an equal opportunity program provider and employer. 



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PART 2: CAVY LICE 

Cavy lice, sometimes referred to as running lice, are host 

specific and need a guinea pig to survive. These lice are 

considered chewing lice, not sucking lice, and actually 

abrade the skin to obtain fluid. 

TYPES 

The most common type of louse is Gliricola porcelli. This 

is a slender, flattened, light colored (white to pale) insect 

about 1 to 1.5 mm in size with no wings. The lice wriggle 

and can be seen moving through the fur near the skin 

and, in heavy infestations, around the eyes. Gyropus ovalis 

is less common and oval in shape, but is also flattened, 

with no wings, and from 1 to 1.2 mm in size. 

A third, and very rare species of louse, is Trimenopon 

hispidium. Light infestations are very easily missed while 

heavy infestations cause hair loss (alopecia), heavy 

scratching, and a rough coat. 

TRANSMISSION 

Lice seldom leave a host and transmission normally 

happens through direct contact with another guinea pig 

or contaminated bedding or other equipment. A person 

carrying an infested animal can also transfer eggs or lice 

from their clothing to another animal. 





LIFE CYCLE 

The life cycle of lice is about three weeks. Eggs are 

attached to the hairs of the host and a nymph will hatch 

three to 14 days later. Next it will go through three 

nymph stages, each about one week, and then molt into 

an adult and begin to mate continuing the cycle. Lice 

have no free living stages and will die quickly in the 

absence of a host. 

SYMPTOMS 

Lice are typically found around the head, neck, ears, and 

rump. Some infestations go unnoticed until the animal 

begins to exhibit physical signs that include: 

-Excessive scratching 

-Hair loss 

-Sores and scabs 

-Scaly, dry, and thickened skin 

Lice are not normally life threatening, but young, 

elderly, and weakened animals will suffer more. A heavy 

infestation may be a symptom of some other underlying 

condition, including malnutrition, chronic disease, or 

immune deficiency, since debilitated animals often do not 

groom themselves, leaving the lice undisturbed. 



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TREATMENT 

While G. porcelli and G. ovalis are specific only to guinea 

pigs, they are highly contagious between guinea pigs. It’s 

important when introducing new pigs into an existing 

group that they are quarantined and examined for lice. 

Topical treatments of ivermectin or imidacloprid can 

easily kill lice, since they are biting not sucking pests. 

Treatment with imidaclopid is by weight, usually at 10 

mg per pound or 0.1 cc per pound. An application will 

usually last for up to 30 days. Since ivermectin is a strong 

drug and absorbed through the skin, an accurate dose is 

required to avoid side effect – including death. 

Insecticides in the class of benzoylphenylureas, such as 

diflubenzuron and triflumuron, have also been found to 

be effective in controlling chewing lice. Always carefully 

read labels to make sure it is appropriate for your animal and 

for proper dosage. It is always recommended to consult your 

veterinarian. 

REFERENCES 

Reeves, W. and Miller, M. Spot-on treatments of 

diflubenzuron and permethrin to control a guinea pig 

louse. Journal of Entomological Science, 44, 410-411. 

Scott, D., Miller, W., and Saunders, W.B. (2001). 

Dermatoses of pet rodents, rabbits and ferrets. Muller 

& Kirk’s Small Animal Dermatology, (6 th ed., pp. 1415- 

1453). Philadelphia, Pennsylvania: C E. WB Saunders 

Company. 

SPECIALIST REVIEW 

Changlu Wang, Extension Specialist in Urban 

Entomology, Department of Entomology, School of 

Biological and Environmental Studies, Rutgers, The State 

University 







Phone: 848.932.5000


PART 3: EAR MITES AND CANKER 

Rabbit ear mites, or Psoroptes cuniculi, are a common 

parasitic problem responsible for the condition known as 

ear canker. Considered one of the most common mites 

of rabbits, it also causes infection in cavies, horses, goats, 

antelopes, sheep, and cattle. Left untreated, canker can 

lead to secondary bacterial infections of the skin or invade 

the middle and inner ear leading to neurological disorders 

and fatal meningitis. 

TYPE 

P. cuniculi is a large, non-burrowing mite, round to oval in 

shape, which can be seen by eye on an infected animal. 

Often, however, the mites invade the deeper regions of the 

external ear canal where they are not visible. The mite is 

clearly visible when on the external folds of the ear and 

inside the ear pinnae (ear flap). Mites pierce the skin at 

the base of hairs and use bell shaped suckers to feed on 

the host’s lymphatic fluids. The mucus and fecal material 

from the mites cause an inflammatory reaction resulting 

in severe itching. 

LIFE CYCLE 

Depending on environmental conditions, the cycle of 

P. cuniculi is about 21 days. Mites will lay eggs in the ear 

wax or dead skin of the host. The eggs hatch into larvae in 

about four days. At this stage, the larvae have six legs and 

will remain in this stage for four days and then begin to 





molt. After another three to 10 days, they become eightlegged 

protonymphs. The protonymphs will then molt 

into adults, which can mate and lay eggs. 

The mites can survive off the host for four to 21 days. The 

survival rate is greatest when temperatures are low and 

humidity high (greater than 75%). 

TRANSMISSION 

Rabbit ear canker is extremely contagious and generally 

spread by direct contact from an infected to non-infected 

animal. Mites simply crawl from one to another. The 

mites can also be transmitted through contact with the 

environment when an animal scratches or shakes, causing 

flakes of the mite-infested canker containing live mites 

and eggs to fall. It is thought that a pre-existing moist 

dermatitis provides a suitable environment for the mites 

to infest. 

Transmission is more likely when large numbers of 

rabbits, or other susceptible hosts, are housed close to one 

another such as overcrowded hutches, pet shops, shelters, 

rabbit breeding facilities, and wild rabbit warrens. 

SIGNS AND SYMPTOMS 

An initial infestation may be overlooked if it begins 

deeper in the ear canal. Owners may notice ear scratching 

and head shaking at this early stage. Other signs include 



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edness, heat, and swelling of the ear canal. As the mites 

multiply, the infestation expands to the outer ear flap 

and, at this point, is clearly visible. It is not unusual to 

have only one ear infested. 

The host animal will normally be very agitated at 

this stage, itching and scratching at its ears and head 

frequently. The self-trauma of itching and scratching 

damages the ear skin even more resulting in more 

inflammation, itching, and scratching. The inflammation 

also causes serum and white blood cells to ooze onto the 

skin surface trapping the mites, feces, and skin cells and 

then drying out. This produces the crusting, scabbing, 

and thick scale or gray, flaky skin debris attached to the 

inside of the ear flap. Underneath the crust, the skin is 

moist, hairless, and raw. 

The crusting and scabbing can spread to the head 

and neck, as well as other parts of the body, through 

grooming or untreated infestations that multiply. Ear 

drooping can also be due to the weight of scabbing 

around the outside of the ear. 

If left untreated, ear canker can lead to secondary 

bacterial infections adding to the pain and discomfort. A 

foul smell to the ear is an indication of an infection. Head 

tilt and signs of being off-balance are also indicators of 

secondary infections and a potential chronic condition. 

TREATMENT 

It is important to treat the infected animal and 

the environment at the same time to prevent recontamination. 

While treating the animal, it is 

recommended to also remove the infected animal from its 

living environment to give the mites and eggs a chance to 

die off. A large sized box or crate with clean, disposable 

bedding makes good temporary housing. 

Two main treatment options are available for treating ear 

mites. Systemic treatments use oral, injectable, or dermal 

absorbed antiparasitic drugs. Topical treatments apply 

antiparasitic medications directly to the infected areas as 

drops, powders, or oils. Systemic treatments are usually 

preferred because they require fewer repeat dosages, ease 

of giving, and better results. 

P. cuniculi are effectively treated with avermectin drugs, 

including ivermectin and selamectin. Injections or 

oral doses of ivermectin repeated over 14 days are 

more effective than topical applications of the same. 

Moxidectin, also an avermectin, has also been shown to 

be effective against ear canker mites. 

Removing the crust and scabs can be extremely painful 

to the animal and there is debate as to whether or not this 

should be done. If treated correctly, the medications will 

allow for easy removal of the crust within a few days or 

it will begin to fall off on its own within 10 to 14 days of 

treatment. 

Because rabbit ear mites can live for up to three weeks off 

a host animal, it is important to decontaminate hutches, 

cages, burrows, feeding sources, and other items in the 

infested animal’s environment. 

Physically remove all contaminated and potentially 

contaminated bedding. It is nearly impossible to 

chemically decontaminate the large surface area of 

bedding whether paper, straw, hay, or wood chips. It is 

best to just remove it all and replace with fresh, clean 

bedding. 

Rest the animal’s environment. Leaving the environment 

free of all rabbits, or other animals, for 4-6 weeks will 

make sure that it becomes mite free. Treat the hutches, 

cages, and bedding with an insecticide that is appropriate 

and safe for the animal. Always read the label carefully 

before using any insecticide chemical on an animal or its 

environment. Some insecticides are toxic to rabbits and cavies. 

Replace or move housing. Some hutches, especially those 

made of porous wood, are difficult to clean and remove 

mites once established. In these cases, it might be easier 

to replace a hutch or cage. If the animal’s housing is 

close and accessible to wild animal populations, consider 

moving or modifying to prevent wild mite-carriers from 

coming into contact with your animals. 

REFERENCES 

Scott, D., Miller, W., and Saunders, W.B. (2001). 

Dermatoses of pet rodents, rabbits and ferrets. Muller 

& Kirk’s Small Animal Dermatology, (6 th ed., pp. 1415- 

1453). Philadelphia, Pennsylvania: C E. WB Saunders 

Company. 

Hansen, O., Gall, Y., Pfister, K., and Wieland, B. (2005). 

Efficacy of a formulation containing imidacloprid 

and moxidectin against naturally acquired ear mite 

infestations (psoroptes cuniculi) in rabbits. International 

Journal of Applied Research in Veterinary Medicine, 3 (4), 

281-286. 







Phone: 848.932.5000

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