The mites are a huge and diverse group of almost 30,000 species. They are extremely variable in structure, behaviour and ecology. The majority of mites are free-living predators, herbivores or detritivores, occupying a wide range of habitats from soil to oceans and from deserts to ice-fields. Only a relatively small number of species are parasites, but some of these are responsible for significant problems in many invertebrates and vertebrates, particularly birds and mammals. The majority of these mite species are ectoparasites, although a small number (about 500 species) are endoparasites, living in the lungs, nasal passages or other tissues.
The ectoparasitic mites of mammals and birds inhabit the skin, where they feed on blood, lymph, skin debris or sebaceous secretions, which they ingest by puncturing the skin, scavenge from the skin surface or imbibe from epidermal lesions. Most ectoparasitic mites spend their entire lives in intimate contact with their host, so that transmission from host to host is primarily by physical contact. Infestation by mites is called acariasis and can result in severe dermatitis, known as mange, which may cause significant welfare problems and economic losses.
Wall, R., Smith, K.E., French, N. P. & Berriatua, E., (1999) Population growth and mortality in Psoroptes ovis infesting sheep. Veterinary Parasitology, 83, 253-264.
Smith, K.E., Wall, R., French, N. P. & Berriatua, E., (1999) Effects of temperature and humidity on the mortality of Psoroptes spp. Veterinary Parasitology, 83, 265-275.
Sanders, A., Frogatt, P., Wall, R. & Smith K.E. (2000) Life-cycle stage morphology of Psoroptes mites. Medical & Veterinary Entomology, 14, 131-141.
Smith, K.E., Wall, R. & French, N.P. (2000) The control of the sheep scab mite Psoroptes ovis with entomopathogenic fungi. Veterinary Parasitology, 92, 97-105.
Mapstone, S.C., Beesley, A. & Wall, R. (2002) Structure and function of the gnathosoma of the mange mite, Psoroptes ovis. Medical & Veternary Entomology, 16, 378-385.