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Studies on the biological control of the sheep scab mite, Psoroptes ovis, using entomopathogenic fungi - OD0538(1)

Ectoparasites are important causes of disease in animals, either through direct pathological effects, or as vectors of viral, bacterial, rickettsial or protozoal diseases. Present control strategies for ectoparasites rely heavily on the use of several neurotoxic chemicals which pose problems of human and environmental toxicity. The emergence of resistant strains further limits effective control of a number of species. There is therefore an urgent need to investigate alternative methods of ectoparasite control in animals.

The use of entomopathogenic fungi as biological control agents has been widely considered in the past. To be effective, fungal pathogens must come into external contact with the target arthropod, penetrate the cuticle, deblitate and ultimately kill the arthropod host. There have been no previous attempts to control ectoparasitic mites with fungi. However, there are sound theoretical arguments to suggest that parasitic mites may form an ideal target for such biological control agents. Firstly,fungal hyphae can more easily penetrate the soft unsclerotised exoskelton which is present at arthropod joints. However, astigmated mites, such as the genus Psoroptes, are completely unsclerotised. Hence the entire surface is avaliable for penetration by fungal hyphae. Secondly, the microhabitat inhabited by ectoparasitic mites is maintained by the bosy of the host at high temperatures and, particularly in the case of sheep, relatively high humidities.

This project will seek to bring together the collaborative expertise of specialists in biological control of agricultural pests with scientists and veterinarians experienced in the control of animal ectoparasites to investigate the potential for entomopathogenic fungi to control the sheep scab mite, Psoroptes ovis.
01: Qualitative production of defined fungal strains.
02: Development of bioassays.
03: Formulation studies on identified fungal strains.
04: Preliminary studies to determine the effectiveness of entomopathogenic fungi in controlling mite infestations on sheep.
Time-Scale and Cost
From: 2000

To: 2003

Cost: £189,321
Contractor / Funded Organisations
Veterinary Laboratories Agency
Animal Diseases              
Animal Health              
Biological Control              
Plants and Animals              
Sheep Scab              
Fields of Study
Animal Health