Lynxacarus radovskyi

From Cat
Lynxacarus spp adult male
Lynacarus adult female

Also known as the feline fur mite, Lynxacarus radovskyi is a rare parasitic mite of cats in temperate and tropical regions of the Americas[1], Australia[2], New Zealand, Fiji[3] and Philippines)[4].

Infestation with Lynxacarus spp parasites lead to dandruff, pruritus and alopecia which must be distinguished microscopically from other causes such as Cheyletiella spp[5].

The small (< 0.5 mm) mite can be readily identified by its laterally compressed body and have short legs anteriorly on the first two-thirds of the body and its characteristic grasping of the hair shaft between the gnathosoma and palpi .The anteriorly directed bridge on the propodosomal plate that contacts the head plate is easily observed. All of the legs have terminal suckers. Adult females are usually larger than the male and usually some of them Ovigerous females. The male mite has a greatly enlarged fourth pair of legs, elongated posterior end with two processes each carries a long lateral hair.

Removal of a few hairs using adhesive tape for microscopic evaluation usually reveals the adult mite. The number of parasites and apparent discomfort in cats varies considerably, from massive infestation with little discomfort to few mites and marked pruritus. Clinical signs included salt-and-pepper appearance to a dull and opaque hair coat, alopecia of the dorsal and lateral areas of the hind limbs, and evidence of self-mutilation with papules and crusts on the hind limbs. The pruritus was mild in animals with low infestation, but very intense in those with a heavy infestation. Most mites occur in the lateral area of the hind limbs and sacral area.

Gingivitis is a rarely reported sequela to chronic overgrooming and gingival irritation by mite antigens[1]. Cats may also present with gastrointestinal disturbances, rectal irritation, or hairballs (due to excessive grooming). In addition, infested cats may have anorexia, restlessness, fever, and weight loss.

These clinical signs can be confused clinically with other causes of pruritus, including:

It is imperative that all in-contact pet mammals, their paraphernalia, and their environment be included in the treatment program. However, environmental treatment is not always performed nowadays, as long as treatment duration is adequate. Indeed, treatment duration, which should cover a minimum period of 6 to 8 wk, is directly influenced by the severity of the infestation, the number of animals involved, the acaricidal product chosen, and whether or not there is concomitant topical or environment decontamination, or both.

Options include one of the following:

  • weekly bathing in pyrethrin shampoo
  • lime sulfur dips every five to seven days for three weeks[6]
  • fipronil - spray one spritz/lb body weight repeated again in three weeks
  • selamectin - topically one dose every 15 days for a total of three doses
  • ivermectin - 300 micrograms/kg orally every week for three weeks (must be heartworm negative first and not used in herding breeds or crosses thereof — also avoid ivermectin in older patients) has been reported as effective[7]
  • milbemycin - 2 mg/kg once weekly for three weeks (one study treated for up to nine weeks)
  • The environment must be treated with a house and carpet spray such as those that are used for fleas. Remember to treat any pet exposed to the affected animal and not just the affected animal.


  1. Craig TM et al (1993) Lynxacarus radovskyi infestation in a cat. J Am Vet Med Assoc 202(4):613-614
  2. Bowman WL & Domrow R (1978) The cat fur-mite (Lynxacarus radovskyi) in Australia. Aust Vet J 54(8):403-404
  3. Munro R & Munro HM (1979) Lynxacarus on cats in Fiji. Aust Vet J 55(2):90
  4. Schwassman, M & Logas, D (2010) How to treat common parasites safely. In August, JR (Ed): Consultations in feline internal medicine. Vol 6. Elsevier Saunders, Philadelphia. pp:390
  5. Romeiro ET et al (2007) [Infestation by Lynxacarus radovskyi (Tenorio, 1974) in domestic cats from Metropolitan Region of Recife, Pernambuco, Brazil. Rev Bras Parasitol Vet 16(3):159-162
  6. Scott, DW, Miller, WH & Griffin, CE (2001) Small animal dermatology. Saunders, Philadelphia. pp:423
  7. Burrows, A (2009) Avermectins in dermatology. In: Bonagura, JD & Twedt, DC (Eds): Kirk's current veterinary therapy XIV. Mosby, St Louis. pp:390