|Ivie, Glen - Wayne|
Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/5/1998
Publication Date: N/A
Citation: N/A Interpretive Summary: The cattle fever tick (CFT) and the disease it transmits, babesiosis or cattle fever, were eradicated from the US after a 50-year eradication program of dipping cattle and temporarily vacating tick-infested pastures. CFT are still widespread in Mexico and other parts of the Americas south of Mexico. A quarantine along the US/Mexico border has prevented CFT reinfestation in the US because all cattle entering the US from Mexico are dipped with chemical pesticides. The CFT has developed resistance to these pesticides which has led to worries that pesticide control may fail in the near future. In order to manage the resistance problem, early detection of resistance is critical. The assay currently in use for detection is laborious and time consuming. Recent developments in molecular biology have made it possible to detect individual resistant insects; this approach is good but requires knowledge of the specific mechanisms of resistance and extensive work to develop "gene probes". In this study, we tried to detect genetic differences among several resistant and susceptible CFT strains. We found definite differences in the different strains, and these differences may be used to identify strains of the CFT. We will use these techniques to develop better methods for practical application in detecting pesticide resistance in field populations of the CFT.
Technical Abstract: The conventional methods of identifying acaricide resistance in a suspect tick population by the UN Food and Agriculture Organization (FAO) packet assay is a laborious and time- consuming process. DNA probes have been demonstrated as rapid and accurate tools for detecting pesticide resistance in insect species. Random-amplified polymorphic DNA (RAPD) has been used by other groups to differentiate species of mosquitoes and populations within a mosquito species. Using different arbitrary oligonucleotides as primers with RAPD, we have demonstrated that various strains of Boophilus microplus show different patterns of DNA fragments on agarose electrophoresis. The unique DNA fragments may be useful for developing probes that can detect acaricide resistance in field pest populations.