Investigation of the molecular basis of parasiticide resistance in Rhipicephalus microplus and Cochliomyia hominivorax

Abstract

The cultural and economic importance of animal production in South America dates back to the colonial era. This continent has one of the largest percentages of the world's total cattle population and countries like Brazil, Argentina and Uruguay play a major role as exporters of a variety of livestock products. Diseases affecting livestock can have a significant impact on animal productivity, on trade of live animals, meat and other animal products, which, consequently, affects the overall process of the economic development of South American countries. The cattle tick, Rhipicephalus microplus, the horn-fly, Haematobia irritans, the screw-worm fly, Cochliomyia hominivorax, the and the botfly, Dermatobia hominis are responsible for major economic losses among livestock in Brazil. Such ectoparasites are controlled by the application of chemical compounds, the ectoparasiticides, but the use of these chemicals can lead to the selection of resistant pest populations. The impact of parasiticide resistance in animal production and the lack of information regarding the molecular mechanisms of resistance motivate this proposal which aims at the comparison of resistant and susceptible strains of two cattle pests, R. microplus, e C. hominivorax. In order to compare the response to the chemical in the different strains, we will use RNA-seq, one of the most accurate techniques to generate genome-wide levels of gene expression. We anticipate that the obtained results, of both technical and biological nature, will be at the forefront of science and that this project will pave the way for subsequent projects also using genomic sequence data that are expected to emerge in the near future. Furthermore, the sequences generated in this project will be a rich genomic resource for future functional studies and will provide raw information for the investigation of new targets for pest control and eradication. (AU)