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Flies Impacting Livestock, Poultry and Food Safety

University of California - Riverside
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End date
  1. Characterize dispersal and population biology of stable flies and house flies, and develop monitoring methods for use in indoor and outdoor environments.
  2. Establish extent of fly-borne dispersal of human and animal pathogens.
  3. Improve management tactics for stable flies and house flies.
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NON-TECHNICAL SUMMARY: We lack basic information on the biology and ecology of house flies and stable flies that is needed to develop comprehensive pest management recommendations. Information lacking includes methods for monitoring flies, expected dispersal of flies from developmental sites, the risk associated with these flies for transmittal of disease pathogens, and the level of resistance to commonly used insecticides. This project will pool national resources to focus research attention to develop a better IPM approach to the control of house and stable flies.

APPROACH: Objective 1: Years 1-3: Genetic analysis of temporal populations of stable flies will be completed. Long range dispersal studies will be initiated and continue through year 5. Natural dispersal of house flies within animal facilities and migration to residential areas will be completed. Development of house fly monitoring protocols will be completed and recommendations made. Methods to limit house fly movement from livestock facilities to residential areas will be evaluated and recommendations made.
Objective 2: Year 1: Identify and begin sampling flies and manure from participating farms. Standardize PCR methodology for reproducible outcomes. Identify target bacteria to be monitored. Year 2: Continue background monitoring of target bacteria on the farm. Sample fly populations to document dispersal pattern from the farms and adjacent properties. Quantify target bacteria associated with flies confirm retention time relative to environmental conditions. Develop models to characterize dispersal. Year 3: Continue background monitoring, fly population sampling and document dispersal patterns from the farms and adjacent properties. Apply and refine model to characterized dispersal. Develop intervention strategies. Year 4: Sample fly populations to document dispersal patterns from the farms and adjacent properties. Quantify target bacteria associated with flies confirm retention time. Apply intervention strategies. Apply model to characterize dispersal. Year 5: Complete analysis, develop recommendations for risk avoidance and formulate intervention strategies.
Objective 3: Years 1-3: Resistance development to novel fly insecticides will be determined in several sections of the US. The nationwide survey of fly insecticide resistance will be conducted and completed. Years 4-5: Resistance management programs will be developed for the novel insecticides and made available to the livestock and poultry industries nationwide. Resistance management programs will be developed and made available to the livestock and poultry industries nationwide.

PROGRESS: 2007/01 TO 2007/12
OUTPUTS: During the past year, I have continued making progress on developing a viable monitoring technique for house flies (Musca domestica). Research in collaboration with Dr. Jerry Higginbotham (Farm Advisor, Fresno Co.) and funded by UC ANR to assess the value of several house fly monitoring techniques demonstrated that fly spot cards were an effective monitoring tool. I have now secured additional funding by UC ANR Demonstration Project Funds to develop object recognition computer programs in collaboration with Dr. Christian Shelton (UCR, Dept. of Computer Science) that will allow for the scanning of fly spot cards followed by data analysis and automated recommendations to make this monitoring tool useful to CAFO managers. Demonstration of this automated system will be conducted in collaboration with Dr. Jerry Higginbotham during the summer of 2008. I have also developed collaborations with faculty from Oklahoma State University to examine the role that flies have in the transmission of food-borne pathogens to processed foods. This collaboration has been partly industry funded and we have already identified that flies found in food production sites are carrying pathogenic bacteria. We have submitted proposals to the USDA NRI to further assess the role of flies in the transmission of food-borne pathogens associated with leafy green vegetables. Over the last few years, in collaboration with faculty at Cornell University (New York) and the University of Florida, I have begun to examine the levels of insecticide resistance in house flies associated with animal agriculture. Lastly, I have begun to examine the apparent attraction of house flies to sources of sugar. It was noted by personnel at a public health agency that house flies could be found in high density in trees infested with homopterans producing honeydews. With funding from the West Valley Mosquito and Vector Control District, Dr. Brad Mullens (UCR Entomology) and I have begun to examine whether these honeydews are attractive for flies, and if so what benefit do they provide to the flies. I expect that this line of inquiry will develop into examining the specific chemical components of honeydew that are serving as mid or long range attractants of house flies and other Dipterans. Dissemination of results: Results have been desiminated through publications in scientific journals and through presentation to commodity groups such as the California Poultry Federation, to public health agencies at annual workshops, and to the scientific community at several scientific meetings.
PARTICIPANTS: 1. Alec C. Gerry (PI) - overall responsibility for project 2. Diane Zhang (Lab Assistant) - rearing of fly colonies, insecticide susceptibility testing 3. Seemanti Chakrabarti (Post-doctoral researcher) - principal researcher examining the role of flies in the transmission of pathogens and the attraction of flies to homopteran honeydew sugars. 4. Asti Wayadande, Justin Talley, and Jackie Fletcher (partner organization, Oklahoma State University) - collaboration to examine the role of flies in the transmission of food-borne pathogens to leafy green crops. 5. Jerry Higginbotham (collaborator, Fresno County Cooperative Extension - collaboration to determine the best method for monitoring house flies at a large dairy. Will also be organizing demonstration project to showcase automated fly monitoring system. 6. Christian Shelton (collaborator, UCR Computer Science) - collaboration to develop object recognition software to count fly spots on monitoring cards and to develop a computer program for data analysis and fly control recommendations. 7. Brad Mullens (collaborator, UCR Entomology) - collaboration to examine the attraction of flies to homopteran honeydews. 8. Jeff Scott, Don Rutz, Phil Kaufmann (partner organization, Cornell University, New York) - part of national team to examine insecticide susceptibility of house flies across the U.S.
TARGET AUDIENCES: Target audiences have included the scientific community reached at several national meetings such as the Livestock Insect Workers Conference and the Entomological Society of America Annual Meeting as well as through publication of research results in scientific journals; commodity groups such as the poultry and dairy reached through presentation at annual workshops such as the California Poultry Federation Workshop and California Dairy Herdsmen Shortcourse as well as publication of short articles in Farm Advisor newsletters or UC ANR publications; and public health agencies reached through presentations at annual meetings and workshops of the Mosquito and Vector Control Association and the California Conference of the Directors of Environmental Health.

IMPACT: 2007/01 TO 2007/12
Research to evaluate fly monitoring methods demonstrated that the use of fly spot cards were effective as a monitoring tool. However, this method of pest monitoring is too time intensive for producers to practice and it was clear that we needed to develop a system that would not over burden producers. With this in mind, I developed the concept of an automated spot card reader linked to a computer program that would provide data analysis and recommendations for control options. This system is currently in development in collaboration with the UCR Computer Science Department and we expect to demonstrate this system at a large dairy operation in summer of 2008 with Dr. Jerry Higginbotham (Farm Advisor, Fresno Co.) My collaboration with faculty at Oklahoma State University has resulted in a finding that flies associated with leafy green production sites located near pastured cattle are carrying pathogenic bacteria. This finding led to the submission of a joint proposal by the OSU faculty and myself to determine the origination site of these infected flies and to determine if these flies are capable of infecting leafy green vegetables with the pathogenic bacteria that they are carrying.

Funding Source
Nat'l. Inst. of Food and Agriculture
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Bacterial Pathogens
Meat, Poultry, Game