Location: Tick and Biting Fly Research2010 Annual Report
1a. Objectives (from AD-416)
Objective 1: Determine if new commercial insecticidal toxicants could be useful as acaricides in the eradication program. Sub-obj. 1.A. Evaluate use of currently available insecticide mixtures that might result in additive or synergistic effects to enhance efficacy in the control of ticks. Sub-obj. 1.B. Evaluate use of long-lasting acaricides for use in regulatory activities of the CFTEP. Sub-obj. 1.C. Evaluate novel methods of acaricide delivery for cattle fever tick control. Objective 2: Develop operationally useful plans for resistance management in fever tick infestations. Sub-obj. 2.A. Evaluate use of Co-Ral for its ability to eradicate organophosphate (OP)-resistant fever ticks in pasture conditions. Sub-obj. 2.B. Characterize emerging resistance to ivermectin and new acaricides in fever tick populations in Mexico. Sub-obj. 2.C. Establish and implement a diagnostic facility to monitor acaricide resistance, define mechanisms of resistance, and provide management strategies for controlling outbreak strains. Objective 3: Develop wildlife-based strategies to eradicate ticks on premises with infested deer, including research on ecology application of anti-tick vaccines and chemicals, novel delivery methods and field trials. Sub-obj. 3.A. Classify habitat preferences of white-tailed deer and cattle fever ticks in Zapata County, TX, using satellite imagery. Sub-obj. 3.B. Analyze genetic associations among populations of southern cattle ticks and cattle ticks, on cattle, white-tailed deer, and other captive and wild ungulates. Sub-obj. 3.C. Evaluate efficacy of ARS-Patented '4-Poster' Deer Treatment Bait Station and medicated baits to eradicate cattle fever ticks feeding on white-tailed deer in infested premises in South Texas. Sub-obj. 3.D. Evaluate efficacy of new acaricides formulated for the '4-Poster' and other topical treatment devices to control blacklegged and lone star ticks feeding on white-tailed deer and cattle fever ticks feeding on deer in infested premises in South Texas. Sub-obj. 3.E. Further develop and field test ARS-Patented Automatic Collaring Device for potential use in applying acaricidal neckbands to control all species of ticks that feed on white-tailed deer. Sub-obj. 3.F. Develop and field test slow-release long-lasting acaricidal neckband formulations for application to deer by the automatic collaring device. Sub-obj. 3.G. Describe relative importance of white-tailed deer as alternative hosts for the dispersal and maintenance of cattle fever tick populations. Objective 4: Perform research to support development of spatial models of adverse economic impact of re-infestation of fever ticks on Texas, other potentially infested states, and the U.S. cattle industry as a whole. Objective 5: Determine risk of Babesia transmission by ticks. Sub-obj. 5.A. Test for presence of Babesia in fever tick outbreak strains in south Texas. Sub-obj. 5.B. Using molecular techniques, evaluate both wild and captive white-tailed deer and exotic ungulates for the presence of Babesia. Sub-obj. 5.C. Determine if Rhipicephalus microplus can acquire Babesia from white-tailed deer and subsequently transmit Babesia to naive cattle.
1b. Approach (from AD-416)
This project addresses the biology and control of ticks of veterinary and human importance with an emphasis on developing technologies to help maintain eradication of cattle fever ticks and the agents that they transmit causing potentially fatal bovine babesiosis and to reduce the risk of humans contracting tick-borne diseases including Lyme disease and human ehrlichiosis. It is a multi-disciplinary project requiring scientists from a wide range of academic specialties, backgrounds, and experiences. The research approach is composed of 5 major objectives including: 1) to evaluate commercially available pesticides for use in the fever tick eradication program, 2) to monitor pesticide resistance in cattle fever ticks and develop plans to mitigate outbreaks of resistant ticks, 3) to develop and evaluate technologies and strategies to eradicate cattle fever ticks or control other tick species feeding on white-tailed deer and other wild ungulates, use satellite image analysis to classify deer habitat preferences, analyze genetic associations among fever ticks and hosts, and to elucidate the relative importance of white-tailed deer as alternative hosts for cattle fever ticks, 4) to continue data input, organization, and development of the GIS database of current and historical fever tick infestation data used to develop descriptive and predictive epidemiological models of fever tick outbreaks, and 5) to determine the risk of Babesia transmission by ticks, including the potential for wild and feral ungulates to serve as reservoir hosts.
3. Progress Report
Research accomplished during the first year of this five-year project has contributed significantly toward meeting the objectives. This multifaceted project addresses control of ticks of veterinary and human importance by developing technologies and methods for host-targeted control of ticks on cattle and white-tailed deer. Discovery, data collection, and analyses supporting these efforts are provided by scientists from disciplines including entomology, acarology, chemistry, ecology, molecular biology, molecular genetics, geography, remote sensing, and immunology. A new long-lasting acaricide was evaluated to treat cattle that could potentially reduce the number of gatherings and treatments of cattle by one-fourth as compared with the standard regulatory treatment intervals, and agreements were finalized to test other long-lasting chemicals for potential use in the eradication program. ARS personnel continued to acquire and enter data into the ARS Cattle Fever Tick GIS Databases that compile numerical and geographic data of current and historical eradication intervention efforts. ARS continues to query these databases to provide APHIS with detailed maps of regulated premises, geo-spatial boundary maps, and summary spatial data of Temporary Preventative Quarantines as defined by the Texas Animal Health Commission. In collaboration with scientists at Texas A&M Kingsville, a multi-year project was begun to evaluate the role of white-tailed deer in compromising the fever tick eradication program, and to improve deployment strategies and efficacy of ARS-patented and developed self-treatment technologies to control fever ticks on white-tailed deer. Major upgrades were made to the ARS-patented deer collaring device, collar components were re-engineered and constructed, and acaricidal collar strapping was developed and manufactured by a foreign company that will be field tested for extended longevity. Initial field tests of these improvements will be implemented during FY 2011. In collaboration with scientists at Northern Arizona University, genetic markers were identified that can be used in genetic studies of spatial associations among geographic populations of fever ticks, and additional microsatellite loci that may be similarly useful in these studies were identified from genomic DNA. A reverse line blot assay was developed to detect genomic DNA in cattle fever tick isolates for the two disease agents that cause bovine babesiosis. Serum samples have been collected from 60 white-tailed deer with potential exposure to fever ticks, 25 similarly exposed nilgai antelope, and 8 deer with no previous exposure to fever ticks that will be used in the development and validation of a cELISA assay to detect the presence of serum antibody against Babesia in exotic ungulates to elucidate their potential role as reservoirs for the disease agents.
1. New acaricide formulation for permethrin resistant fever ticks on deer. Recently there has been much concern that acaricide-resistant cattle fever ticks may enter the U.S. from Mexico and compromise eradication of these ticks from the U.S. Routine bioassays to evaluate acaricide resistance in outbreak strains of these ticks detected four strains that were highly resistant to the pyrethroid acaricide permethrin. While these resistant ticks could easily be controlled if they were on cattle by dipping the cattle in the organophosphate acaricide coumaphos, the only acaricide appropriate for use on rollers of "4-Poster" Deer Treatment Bait Stations and "2-Poster" Deer Treatment Feeder Adapters to topically treat white-tailed deer was permethrin based, and this would not be effective against the resistant ticks. To facilitate control of these permethrin-resistant ticks on deer, a formulation of the formamidine acaricide amitraz was developed and transferred to personnel of the Cattle Fever Tick Eradication Program.
Perez De Leon, A.A., Strickman, D.A., Knowles Jr, D.P., Fish, D., Thacker, E.L., De La Fuente, J., Krause, P.J., Wikel, S.K., Miller, R., Wagner, G.G., Almazan, C., Hillman, R., Messenger, M.T., Ugstad, P.O., Duhaime, R.A., Teel, P.D., Ortega-Santos, A., Hewitt, D.G., Bowers, E.J., Bent, S.J., Cochran, M.H., Mcelwain, T.F., Scoles, G.A., Suarez, C.E., Davey, R.B., Freeman, J.M., Lohmeyer, K.H., Li, A.Y., Guerrero, F., Kammlah, D.M., Phillips, P.L., Pound, J.M. 2010. One Health approach to identify research needs in bovine and human babesioses: Workshop report. Parasites & Vectors. 3:Article 36.