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- A parasitic skin
disease that is highly contagious and occurs in rabbits, cats and dogs. It
is caused by an infestation of Cheyletiella species mites. (B609.2.w2)
- This is a non-burrowing mite that lives on the keratin layer of the
epidermis of the skin. (B600.9.w9,
B604.5.w5, B609.2.w2)
- The mites create pseudo-tunnels through the debris and scale on the
skin surface (B600.9.w9)
- The clinical signs of pruritus and scaling may mimic other diseases. (B609.2.w2)
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| Lagomorphs |
- Cheyletiella parasitovorax is a fur dwelling mite that may be
found in significant numbers in pet rabbits. (B600.16.w16,
B601.13.w13, B608.21.w21)
- It may cause patches of dense, flaky, encrusted skin along the
dorsum especially on the neck, the interscapular area, and above the tail base. (B600.16.w16,
B609.2.w2)
- Healthy rabbits with normal grooming habits usually remain
asymptomatic. Disease more commonly occurs in young or debilitated
animals or those with an underlying disease that prevents adequate
grooming. Disease may also be seen in hypersensitive hosts. (B608.21.w21,
B609.2.w2)
- "The presence of mites may not be associated with disease
and they can be considered to be commensal ectoparasites". (B600.9.w9)
- Cheyletiella is one of the arthropod vectors for the viral disease of Myxomatosis.
(B603.4.w4,
B615.6.w6)
- Cheyletiella parasitovorax can be spread to dogs and cats. (B606.4.w4)
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Disease Author |
Nikki Fox BVSc MRCVS (V.w103) |
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Referees |
Anna Meredith MA VetMB CertLAS DZooMed (Mammalian) MRCVS (V.w128);
Richard Saunders BVSc BSc CertZooMed MRCVS (V.w121) |
Major References /
Reviews
|
Code and Title List |
B284.10.w10,
B600.9.w9,
B600.16.w16, B601.13.w13,
B 602.19.w19, B603.4.w4,
B604.5.w5, B606.4.w4 B608.21.w21, B609.2.w2,
B614.11.w11
J15.29.w1, J29.5.w1,
J29.5.w2, J213.4.w4, J213.7.w1,
J476.19.w1, J478.4.w1
D600.1.w1
P600.1.w1 |
Other References
|
Code and Title List |
B600.4.w4,
B601.15.w15, B614.8.w8,
B615.6.w6
J11.55.w2, J469.360.w1
P601.1.w1 |
Detailed Clinical and Pathological Characteristics
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| General |
The clinical signs of pruritus and scaling may mimic other diseases. (B609.2.w2)
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Clinical
Characteristics |
Many cases are subclinical with no apparent skin damage. (J213.4.w4)
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| Lagomorphs |
Clinical findings
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Incubation |
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| Lagomorphs |
Life cycle of Cheyletiella parasitovorax:
- The life cycle of this mite is approximately 35 days and this is all spent on the host. (B609.2.w2)
- The life cycle is 14-21 days. (B601.13.w13)
- Ova are attached to the hair shafts two to three millimetres above the base
of the hair shafts. (B614.11.w11)
- There are two nymphal stages. (B600.9.w9)
- Mites obtain tissue fluid from the host. (B614.11.w11)
- The adult female mites and eggs of Cheyletiella parasitovorax are
able to live 10 days off the host. (B600.9.w9,
B601.13.w13)
- However, adult males, nymph and larvae are less resistant and die in
2 days in the environment. (B600.9.w9)
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Mortality / Morbidity |
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| Lagomorphs |
- "The presence of mites may not be associated with disease
and they can be considered to be commensal ectoparasites". (B600.9.w9)
- A survey of 220 laboratory rabbits was carried out and 43.2% of the
rabbits had inapparent infestations of Cheyletiella parasitovorax. (B600.9.w9)
- "Skin lesions associated with mange mites are uncommon in
free-living lagomorphs". (B284.10.w10)
- "Disease caused by rabbit fur mites, Cheyletiella sp.
and Leporacarus gibbus, is the most common rabbit skin disease
in the author's practice, present on more than 15% of the rabbits seen".
(J213.4.w4)
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Pathology |
Histopathology
- A subacute dermatitis. (J213.4.w4)
- Hyperkeratosis of affected skin with an inflammatory cell exudate
(plasma cells, mononuclear phagocytes, eosinophils and lymphocytes). (B602.19.w19)
- There may also be polymorphonuclear neutrophils present. (J213.4.w4)
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General Information on Investigation / Diagnosis
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- Cheyletiellosis must be considered in every rabbit that presents
with scaling, with or without pruritus. (B609.2.w2)
- Mites may be found anywhere on the body but the usual site is along
the dorsum especially at the tail base and the interscapular area. (B600.9.w9)
- Note: it is important to identify any underlying disease that may
be preventing normal
grooming behaviour. (B609.2.w2)
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| Lagomorphs
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Clinical examination: thorough examination including oral,
neurological and orthopaedic. (B609.2.w2)
Examination of epidermal debris:
- Collect samples by using a flea comb (the most effective method),
acetate tape, or skin scrape. (B602.19.w19,
B609.2.w2, J29.5.w1)
- Alternatively, "gently vacuuming the animal with a pipette
attached to a suction unit or small commercial vacuum works very well.
A small piece of milk filter paper placed in the line traps debris
which can be examined microscopically. Pruritic animals especially
seem to enjoy the motion of the pipette and the technique is
atraumatic and efficient for recovering ectoparasites". (B615.6.w6)
- Cheyletiella are large mites so it is only necessary to examine the debris
under low
magnification. It is not necessary to use any staining. (B609.2.w2)
- Mites might be seen moving among the skin flakes that are placed
under a bright light. (B600.16.w16)
- To the naked eye, they can be identified as clear to pale yellow
to white oval to saddle-shaped mites that are approximately 0.3 mm long with hook-like mouth parts and inward curving claws.
(B602.19.w19,
B604.5.w5, B614.11.w11,
J213.4.w4)
- The legs terminate in short hair-like setae. (B614.11.w11,
J213.4.w4)
- Mites can also be identified by removing the flakes from the skin and
then applying acetate strips to the exposed area of skin. Place this
strip on a microscope slide and then examine under low power
magnification. (B600.16.w16,
B602.19.w19)
- If there is a heavy infestation, it might be possible to see
eggs, nymphal stages and adult mites. (B600.16.w16)
Skin biopsy with histological examination: can be used to rule
out sebaceous adenitis. (B609.2.w2)
Imaging: dental or spinal radiographs to rule out any underlying
musculoskeletal or dental disease. (B609.2.w2)
See:
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| Related Techniques |
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Specific Medical Treatment
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- Treatment is recommended because this is a zoonotic condition. (J213.7.w1)
- Treat all the animals in the household including dogs and cats. (B601.13.w13,
B609.2.w2)
NOTE:
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| Lagomorphs |
Treatment involves killing the mite, removing scale and treatment of any
underlying grooming difficulties. (B600.9.w9)
Drugs of choice:
- Ivermectin
- Treatment of choice. (B601.13.w13,
B608.21.w21)
- Effective treatment (B615.6.w6,
J29.5.w1)
- Usually effective. (B609.2.w2)
- 0.4 mg/kg by subcutaneous injection every 10-14 days for three
doses. (B601.13.w13,
B602.19.w19,
B606.4.w4,
B609.2.w2)
- Effective in killing the mites. A second dose is necessary 10-14
days after the first. (B600.9.w9)
- Not licensed for use in rabbits but no adverse reactions have
been reported. (B609.2.w2)
- "Treatment with ivermectin reduces the population of Cheyletiella
spp. mites; however, the infestation has not been eradicated in
many cases treated at the author's practice". (J213.4.w4)
- Selamectin
- A very effective treatment for this condition; a single dose
seems to last long enough to eliminate all stages of the life
cycle. Routine administration is recommended for rabbits that
cannot groom themselves properly. (P601.1.w1)
- 6-18 mg/kg applied topically once only. Single application seems
to be effective. (B600.4.w4,
B601.15.w15)
- 6-12 mg/kg applied topically. Repeat in 2-4 weeks if necessary.
(B609.2.w2)
- In a study of 23 rabbits with cheyletiellosis, a single dose of
topical selamectin at 12 mg/kg was proved to be effective in the
treatment of this disease. At five weeks post treatment, all of
the rabbits were negative for mites and eggs. (J476.19.w1)
- Not licensed for use in rabbits but no adverse reactions have
been reported. (B609.2.w2)
- Imidacloprid and moxidectin
- Imidacloprid plus moxidectin at 10 mg/kg and 1
mg/kg respectively, subcutaneously every four weeks for three
treatments. (P600.1.w1)
Other Medications:
- Carbaryl powder (5%) (Carbamates)
(J29.5.w2)
- Apply as a topical treatment once a week. (B609.2.w2)
- Use powder that is appropriate for cats, twice a week for six
weeks. (B602.19.w19)
- May also use this to treat the environment. (B609.2.w2)
- Successful when used repeatedly but there have been reports of
toxicity problems. (J213.4.w4)
- Lime sulphur rinses
- These have also been effective but are reportedly difficult to
use in rabbits - see "precautions" below. (B609.2.w2)
- Use once weekly for three to six weeks. (B 602.19.w19)
- "good success with 3 to 4 weekly dips". (J213.4.w4)
- See: Bathing Rabbits
- 0.01%
Amitraz
- Amitraz must be diluted 1:500 to achieve this concentration.
Dipping is necessary once a week for up to 6 weeks. (B606.4.w4)
- Permethrin
powder (J29.5.w2)
- Cheyletiella can be reduced by dusting the adult rabbits,
weanlings and the bedding at weekly intervals. (B604.5.w5)
- Pyrethrin
flea powders designed for kittens. (J29.5.w1,
J29.5.w2)
Reinfestation:
- Investigate if the animal has contact with an asymptomatic carrier
or if there is an unidentified source of mites, for example, untreated
bedding. (B609.2.w2)
Contraindications:
- Do not use the following on rabbits: Fipronil, flea
collars or products
containing Organophosphates.
(B609.2.w2)
See
- Dog and cat topical flea preparations. (B609.2.w2)
Precautions:
- Dipping or bathing rabbits: there is a high risk of skeletal fractures
or excessive chilling if performed by inexperienced people. "Sudden
death has also been reported during or after bathing rabbits."
- Off-label use of medication: most flea control products are
not licensed for use in rabbits and therefore their efficacy and
safety have not been evaluated in this species. Use with caution particularly
in debilitated or young animals.
- Licking of topical spot-on products: must prevent the animal
or its cage mate from doing this before the product has had chance to
dry.
- Adverse reactions to pyrethrins and pyrethroid-type flea
products: clinical signs include hypersalivation, muscle tremors,
ataxia, depression, anorexia, and dyspnoea [if a very large excess
dose is given]. (See: Permethrin and Pyrethrin Toxicity in Rabbits)
- Toxicity: If signs of toxicity are shown, the rabbit must be
bathed thoroughly to remove remaining chemicals and have appropriate
treatment.
(B609.2.w2)
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| Related Techniques |
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Environmental
and Population Control Measures
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| General Environment Changes, Cleaning and
Disinfection |
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Lagomorphs |
- The environment needs to be cleaned regularly. This is very important
for eliminating the infestation as adult females and eggs of Cheyletiella
parasitovorax may live up to ten days
off the host. (B600.9.w9,
B601.13.w13, B609.2.w2)
- However, adult males, nymph and larvae are less resistant and
die in two days in the environment. (B600.9.w9)
- Disinfect the environment by using flea products (i.e. carbaryl 5%
dust). (B602.19.w19)
- Spray the hutch with an environmental flea product, e.g. Vet-Kem
Acclaim Plus (Sanfoni Animal Health Ltd.) which contains 0.58% permethrin
and 0.09% w/w S-methoprene. (B606.4.w4)
- Remove and discard all the organic material from the cage (paper
or wood products, bedding). (B609.2.w2)
- Replace the bedding with shredded paper bedding and discard this
daily along with thoroughly daily cleaning of the cage during the
treatment period. (B609.2.w2)
- Discard or thoroughly disinfect any grooming utensils before
reuse. (B609.2.w2)
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| Population Control Measures |
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| Lagomorphs |
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| Isolation, Quarantine and Screening |
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| Lagomorphs |
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| Related Techniques |
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