2007 Annual Report
1a.Objectives (from AD-416)
The overall objective of this research is to develop effective and environmentally safe tools and sustainable strategies for the integrated management of livestock pests. Toward that goal our specific objectives for the next 5 years are to: .
1)Develop and improve methods of chemical control of horn flies and stable flies;.
2)Develop alternatives to classical chemical control of horn flies and stable flies; and.
3)Develop and evaluate control strategies to provide sustainable pest management practices.
1b.Approach (from AD-416)
Use in-vitro and in-vivo bioassays to evaluate new classes of chemical control agents against horn flies and stable flies. Develop and improve both conventional and controlled release chemical delivery systems to increase the effectiveness, improve efficiency, reduce the quantity of pesticide needed, and improve the safety of chemical control. Develop biological and physical control technologies for blood-feeding flies on cattle. Create and use simulation models to serve as a framework to guide both research and implementation of sustainable control programs. Develop and test sustainable horn fly and stable fly management strategies for pastured cattle. Develop computer assisted decision-aid programs for use by extension personnel and producers. Develop protocols for the selective breeding of cattle resistant to horn flies.
Medicated-molasses for control of horn flies:
The horn fly continues to be the most economically important pest of cattle in the U.S. In an effort by the Knipling-Bushland US Livestock Insects Research Laboratory (Kerrville, TX) to develop improved control technologies and strategies, we demonstrated that 10 ppm of doramectin in molasses provided ad lib to pastured cattle completely inhibited horn fly development in the manure. Strategically providing the medicated molasses for 3 weeks and not retreating until fly populations returned to 100 per animal provided an effective, efficient and inexpensive means of maintaining populations below the 200 flies/animal economic threshold. Reinfestation was attributed mainly to movement of flies from adjacent untreated cattle. In addition to the practical application of the medicated-molasses for horn fly control, the results point to the potential of using a medicated protein/molasses block. (NP104; Component 4, Control Technology)
Thromostasin variants in horn flies on cattle:
Variants of a horn fly anti-coagulant, thrombostasin, that were unique to a Texas field collection were identified. The frequency for all variants in horn flies collected from cattle hosts specifically phenotyped as high- or low-carriers of horn flies was evaluated, demonstrating a significant difference between thrombostasin variants of flies collected from these high- versus low-carrier hosts. This contributes to our understanding of what may make one bovine host more suitable for flies than another within the same herd. Specifically, the data suggested that thrombin, the target of horn fly thrombostasin, may differ between hosts and potentially provide a marker for host resistance to the horn fly. (NP104; Component 3, Biology and Physiology)
|Number of invention disclosures submitted||1|
|Number of patent applications filed||1|
|Number of web sites managed||1|
|Number of non-peer reviewed presentations and proceedings||8|
|Number of newspaper articles and other presentations for non-science audiences||3|
Olafson, P.U., Pruett Jr, J.H., Atteberry, H.N., Steelman, C.D. 2006. Thrombostasin isoform frequency in a Central Texas field population of the horn fly, Haematobia irritans. Veterinary Parasitology. 142:359-366.
Lohmeyer, K.H., Miller, J.A. 2006. Pathogenicity of three formulations of entomopathogenic fungi for control of adult Haematobia irritans (Diptera: Muscidae). Journal of Economic Entomology. 99(6):1943-1947.
Lohmeyer, K.H., Kammlah, D.M., Pruett Jr, J.H. 2006. White eye color mutant in Haematobia irritans (Diptera: Muscidae). Annuals of the Entomological Society of America. 99(5):966-968.