Chapter 21 – Arthropods

Publisher Summary Arthropod parasites remain as important pathogens of laboratory mice. Access to the host by a number of parasitic species has been interdicted by at least two major factors acting in concert: (1) commercial and institutional applications of gnotobiotic principles for the development of parasite-free production colonies, with the consequently common availability of arthropod-free mouse stocks; and (2) general acceptance of the principles of modern colony management. These factors have essentially limited arthropod parasitism of laboratory colonies to a handful of relatively species–specific forms that must live their entire life cycle on the mouse host: Polyplax serrata, Myobia musculi, Radfordia affinis, ρsorergates simplex, Myocoptes musculinus, and Trichoecius romboutsi. This chapter discusses these forms. The older literature makes frequent reference to a diversity of arthropod forms. Many of these species are now only rarely encountered as parasites of laboratory mice. Such parasites include the fleas, true bugs, and mesostigmatic mites, all of which are forms that must spend a part of their life cycle off the host. These have been the parasitic species most vulnerable to the pathogen barriers and sanitization standards characteristic of modern animal facilities. The few citations of parasitism with such species in recent years have occurred as surveys of wild mouse populations or as reports of infestations in colonies with deficient care standards.