Mange: burrowing mites
Sarcoptes scabiei or Notoedres cati
Esther van Praag, Ph.D.
MediRabbit.com is funded solely by the generosity of donors.
Every donation, no matter what the size, is appreciated and will aid in the continuing research of medical care and health of rabbits.
Warning: this file contains pictures that may be distressing for people.
Rabbits can be affected by mange, caused by burrowing mites. Sarcoptes sp. is encountered all over the world, though not with equal frequency. Rabbits in northern Europe and England are barely affected by mange; in Israel and subtropical humid regions, they appear the number one cause of skin parasitic infestations in rabbits. In the US it varies according to the region. Burrowing mites present a zoonotic danger; they can affect dogs, cats, and humans, causing a transient itching dermatitis. The burrowing mange Notoedres cati is occasionally observed to infest rabbits.
These parasites spread rapidly from one rabbit to another, through nymphs and larvae that live on the surface of the skin. Only the adult female will dig into the skin and make tunnels where it lays up to 5 eggs, with a maximum of 50 during her whole life. The larvae that hatch from those eggs live the first stages of their life in those tunnels. Only the male adults and older larvae live on the surface of the skin. The complete life cycle from egg to adult lasts about 2 to 3 weeks. This should be taken into account when treating a rabbit.
Symptoms and clinical signs
Wounds appear first on the lips and nose, later around the head, neck, and sometimes around the genitalia. Burrowing mites (mange) will lead to heavy scratching by the rabbit, which will also lick the affected areas. This leads to alopecia (loss of fur). Often one can observe the secretion of a watery stuff that forms crusts upon drying. Self-mutilation will lead to wounds and secondary bacterial infection.
Severe infestation leads to anemia and leucopenia (decrease of white cells in the blood). The rabbit becomes lethargic and can die within a few weeks.
Diagnosis can be difficult and visual examination is not always sufficient to confirm the presence of these mites. Detection methods include the tape method, skin scraping (shallow if fur mites are suspected, deep if burrowing mites are suspected), or the vacuum aspiration method on a filter paper. Samples from scraping or aspiration should be spread on a microscope glass, dissolved in KOH, and examined under a microscope. Great is the chance to see a at least one mite or a larva or eggs. Fur can also be sampled, dissolved in KOH, and examined under the microscope for the presence of eggs. If no mite is present in the first sample, other places on the body should be checked. If the presence of burrowing mites is suspected, but none found after a deep skin scraping, a biopsy on the area suspected of mite infestation is advisable.
Mange is treated with 3 injections of ivermectin, one every 14 days. The environment should be thoroughly cleaned, as the mite can survive for weeks without the presence of the rabbit host. Wounds can be treated with benzyl benzoate every 5th day.
Moxidectin (Quest® or Equest® - Fort Dodge) has proved efficacious in treating sarcoptic mange in rabbits. It has so far not shown secondary effects in rabbits when administrated orally, while secondary effects have sometimes been observed after subcutaneous administration.
Sarcoptes scabiei can infest dogs, cats, and man. If the sarcoptic mite infestation is not resolved, the presence of dogs and cats, both possible asymptomatic carriers, or of parasites that survived the treatment should be considered.
If the affected rabbit presents severe anemia, a transfusion of blood can be attempted from a healthy donor rabbit.
Burrowing mites (live on/in the skin) can fall off and contaminate the environment. While treating for mites, careful cleaning of the cage and environment is recommended. Treatment of the environment is important (boric acid such as Fleabusters®; Vet-Kem Acclaim Plus® - Sanofi; Staykil® - Novartis; Indorex® - Virbac; acaricide spray). When treating a carpet, vacuum first in order to further penetration of the spray or powder. Shampooing and steam cleaning are not ideal; their residual humidity can increase the mite problem. During treatment of the environment, rabbits should be kept in another part of the home to avoid the danger of contact with the products.
For further information on Sarcoptes scabiei in rabbits,
see: “Skin Diseases of Rabbits”, by E. van Praag, A. Maurer and T. Saarony,
408 pages, 2010.
Thanks are due to K. Hermans, DVM (Kliniek voor Pluimvee en Bijzondere Dieren, University of Gent, Belgium), to Z. Aizenberg, DVM (The Koret School for Veterinary Studies, The Hebrew University of Jerusalem, Israel), to Einam Livnat, and to Berend Bakker (Indonesia) for the permission to use their illustrative material.
Beck W. Farm animals as disease vectors of parasitic epizoonoses and zoophilic dermatophytes and their importance in dermatology. Hautarzt. 1999; 50(9):621-8.
Cerny V, Rosicky B. Mammals as source of ectoparasites in towns. Folia Parasitol (Praha). 1979; 26(1):93 5.
Isingla LD, Juyal PD, Gupta PP. Therapeutic trial of ivermectin against Notoedres cati var. cuniculi infection in rabbits. Parasite. 1996; 3(1):87-9.
Nfi AN. Ivomec, a treatment against rabbit mange. Rev Elev Med Vet Pays Trop. 1992; 45(1):39-41.
Wagner R, Wendlberger U. Field efficacy of moxidectin in dogs and rabbits naturally infested with Sarcoptes spp., Demodex spp. and Psoroptes spp. mites. Vet Parasitol. 2000; 93(2):149-58.