Introduction of nonindigenous arthropod pests of animals.

A variety of pathways exist for the introduction of nonindigenous insects, ticks, and mites of veterinary importance into the United States. The most prominent includes the natural migration of mosquitoes and flies by the flight of adults, ectoparasites entering the country on wildlife transport hosts, and accidental introductions on animals legally imported through United States Department of Agriculture (USDA) quarantine facilities. Examples of the establishment and subsequent eradication of exotic pests of livestock are presented to illustrate the critical role of the USDA in protecting American agriculture with particular emphasis on the southern cattle tick, Boophilus microplus (Canestrini), the cattle tick, B. annulatus (Say), and the screwworm, Cochliomyia hominivorax (Coquerel). Priority group rating of nonindigenous arthropod pests and disease vectors are discussed. Although the primary responsibility for preventing the introduction and establishment of arthropods that affect livestock and poultry rests on the shoulders of USDA professionals, insect surveys by extension entomologists along with observations by research specialists and producers are also important in detecting exotic arthropod species. Animal health professionals from all sectors of the livestock and poultry industries may well be the first line of defense from the introduction of nonindigenous arthropods and the diseases they transmit.

Integrated control of ectoparasites.

Integrated control of ectoparasites of veterinary importance is being implemented on a limited basis at present. However, several forces are accelerating a global shift to integrated pest management (IPM). These accelerating forces include the following: reduction in new chemical compounds registered for use on livestock and poultry universal development of resistance to pesticides heightened environmental sensitivities to exclusive dependence on pesticide-based control need for strategies which increase profits for the producer while decreasing costs to the consumer. Integrated pest control requires many technologies for incorporation into specific pest management systems. Individual components include new chemicals, formulations and delivery systems, biological control, mechanical control, immunological control, genetic control, and regulatory control. Computer simulation models based on a quantitative ecological database are invaluable in devising and monitoring IPM approaches to controlling ectoparasites which affect livestock and poultry. IPM strategies have been developed for pests of veterinary importance, but eventually these must be incorporated into total livestock production systems. For implementation, a number of major impediments to IPM must be overcome. These problems can best be solved through a vigorous technology transfer programme. In addition to face-to-face meetings between producers and extension agents, the implementation of IPM can be further encouraged at producer group meetings, through education of animal health professionals, by the publication of articles in producer magazines, and by radio and television broadcasts to the agricultural sector. Research focusing on the development of cost-effective and environmentally-compatible IPM systems is necessary for future progress.