Location: Livestock Arthropod Pests Research
Project Number: 3094-32000-038-000-D
Project Type: In-House Appropriated
Start Date: Oct 1, 2014
End Date: Sep 30, 2019
Objective:
Objective 1: Develop new attractants, repellents, and behavior-modifying chemicals based on physiology of chemical reception in house, stable and horn flies. Subobjective 1A: Assess compounds for potential behavior-modifying properties. Subobjective 1B: Elucidate biting fly chemosensory protein function.
Objective 2: Evaluate efficacy of novel technologies for control of house, stable and horn flies. Subobjective 2A: Evaluate the efficacy of various compounds as insecticides to control biting flies. Subobjective 2B: Identify and evaluate novel approaches for existing molecular targets and tools for assessment of new targets for biting fly control.
Objective 3: Determine interactions between flies (of all stages) and microorganisms that significantly affect survival of the insects and their capability to transmit pathogens. Subobjective 3A: Characterize the horn fly gut innate immune response to microbial infection. Subobjective 3B: Define the reservoir and vectorial capacity of biting flies for microorganisms that are pathogenic to livestock and humans.
Objective 4: Complete development of a transgenic male-only strain of screwworms ready for production and distribution, coordinating a critical path to development.
Objective 5: Complete development of screwworm attractants and oviposition stimulants to be used in baits and to help synchronize rearing procedures.
Objective 6: Perform research to accomplish efficiency in the screwworm rearing process. Subobjective 6A: Develop and transfer technology for reducing ammonia emissions from screwworm larval media when cellulose fiber is used as the bulking agent. Subobjective 6B: Determine where optimum rearing environments exists within the large rooms of the screwworm mass rearing facility so to ensure maximum efficiency of the rearing process.
Objective 7: Develop ecological niche models of screwworm flies and genetic subpopulations with the practical objectives of scaling release rates to habitat and to provide projections of potential range changes in response to climate change. Subobjective 7A: Determine genetic variation of screwworms from different geographic origins across their current range. Subobjective 7B: Use remote sensing and geographical information systems to relate genetic variation of screwworms to differences in landscape across their range.
Approach:
Identify new attractants, repellents, and behavior-modifying chemicals based on assessment of natural and synthetic compounds for behavior-modifying properties.
Identify and elucidate structure activity relationships of biting fly chemosensory proteins and behavior-modifying chemicals. Identify lead compounds for further development based on behavior-modifying properties and structure activity relationships. Identify physiological pathways for development of novel control technologies by targeting key components. Evaluate the efficacy of natural and synthetic compounds as insecticides for control of biting flies.
Modify structure of lead compounds and assess effects on compound efficacy to identify structural attributes contributing to and enhancing biological activity. Evaluate efficacy of gene silencing based on key physiological targets for biting fly control. Evaluate efficacy of vaccines based on key physiological targets for biting fly control. Elucidate interactions between flies (of all stages) and microorganisms that significantly affect survival of the insects and their capability to transmit pathogens, including the innate immune response of biting flies to microorganisms in the fly gut. Elucidate the reservoir and vector competence of biting flies for microorganisms that are pathogenic to livestock and humans.
Measure fitness parameters of transgenic screwworm lines and determine if transgenic males are competitive with wild type screwworm males. Confirm stability of transgenic line(s), and screen for mobilization of the transgene in bio-secure facility. Examine influence of genetic background on level of female lethality by crossing transgenic males with females collected from different locations. Record female screwworm antennal responses to chemical stimuli. Transfer transgenic line(s) with favorable fitness to COPEG. Test active chemicals for fly attraction and oviposition stimulation to improve field surveillance and enhance egg production during mass-rearing. Determine optimum dose of potassium permanganate and Yucca extract in screwworm larval media for ammonia reduction and good fly quality yields in diet bulked with cellulose fiber. Yucca schidigera (powder extract) will be added to larval diet at select intervals to determine synergistic activity in ammonia reduction. Measure temperature and humidity in separate rooms, each containing first 3 developmental stages of the screwworm life cycle. Design and develop GIS-based methodology for spatial analysis of each room. Determine general landscape patterns using satellite images at multiple locations across endemic areas from which screwworms were sampled and genotyped. Climatological data, along with general soil information, vegetation data, host composition and density, and land use patterns, will be collected and analyzed using remote sensing technologies and landscape genetics models to understand interactions between gene flow and geographic variation. This will help assess risk for screwworm cases in the barrier zone in Panama, and to prevent outbreaks in the U.S.
