July 23rd, 2025
Researchers at USDA’s Agricultural Research Service (ARS) are investigating the microbial communities carried by house flies to enhance disease monitoring and reduce the risk of disease transmission by fly-borne pathogens in livestock, ultimately protecting our food supply and public health.
House flies play a crucial role in transferring harmful bacteria, viruses, and other microbes among cattle. They also have the potential to spread these pathogens from farms to nearby livestock operations and residential areas.
Adult house flies often have unrestricted access to farm waste, cattle manure, and animal excretions. Flies can pick up microbes from these sources and then spread them, potentially affecting livestock health, welfare, and production efficiency. This can contribute to significant economic losses. According to a previous study, it is estimated that U.S. producers spend over $1 billion annually on implementing fly control programs alone.
Effective fly management can mitigate the spread of disease-causing bacteria and viruses, thereby improving livestock health and reducing potential risks to human health.
RS researchers, university partners, and cattle producers are collaborating to study the types and numbers of microbes carried by adult house flies to assess their role as sources and disseminators of bacteria and viruses within confined dairy farms and, potentially, to neighboring operations.
In a study conducted in collaboration with Kansas State University (KSU), researchers determined that examining the genomic DNA (the complete set of genetic material in an organism) extracted from pools of individual adult female house flies in a specific location can provide a comprehensive overview of the microbes present in their local environment. House flies act as natural “flying swabs,” collecting microbial samples from diverse sources like sick animals or their waste. This innovative approach could potentially serve as a new tool to monitor and study microbes in the environment by allowing scientists to efficiently and safely analyze microbes in the field.
"The numbers of animals, their health status, the composition, and volume of cattle manure, and other environmental conditions at dairy cattle operations vary from month to month, which in turn affects the abundance and types of microbes that will be present and therefore accessible by house flies," said Dana Nayduch, a research leader and entomologist at the Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research in Manhattan, KS.
"By looking at what flies are carrying within and on their bodies over time, we can directly assess what is going on in their surrounding environment on the farm, as they acquire those microbes from these sources all day, every day. In fact, if there is a sick animal on a farm, a fly is attracted to it and will find that needle in the haystack for you, potentially among thousands of animals, and feed upon it and collect its microbes in the process," explained Nayduch.
The insights gained from these ongoing studies can offer farm managers early warnings about the presence of harmful bacteria and viruses in their operations, enabling them to take preventive measures to protect cattle against potential severe illnesses or even outbreaks. back...
House flies play a crucial role in transferring harmful bacteria, viruses, and other microbes among cattle. They also have the potential to spread these pathogens from farms to nearby livestock operations and residential areas.
Adult house flies often have unrestricted access to farm waste, cattle manure, and animal excretions. Flies can pick up microbes from these sources and then spread them, potentially affecting livestock health, welfare, and production efficiency. This can contribute to significant economic losses. According to a previous study, it is estimated that U.S. producers spend over $1 billion annually on implementing fly control programs alone.
Effective fly management can mitigate the spread of disease-causing bacteria and viruses, thereby improving livestock health and reducing potential risks to human health.
RS researchers, university partners, and cattle producers are collaborating to study the types and numbers of microbes carried by adult house flies to assess their role as sources and disseminators of bacteria and viruses within confined dairy farms and, potentially, to neighboring operations.
In a study conducted in collaboration with Kansas State University (KSU), researchers determined that examining the genomic DNA (the complete set of genetic material in an organism) extracted from pools of individual adult female house flies in a specific location can provide a comprehensive overview of the microbes present in their local environment. House flies act as natural “flying swabs,” collecting microbial samples from diverse sources like sick animals or their waste. This innovative approach could potentially serve as a new tool to monitor and study microbes in the environment by allowing scientists to efficiently and safely analyze microbes in the field.
"The numbers of animals, their health status, the composition, and volume of cattle manure, and other environmental conditions at dairy cattle operations vary from month to month, which in turn affects the abundance and types of microbes that will be present and therefore accessible by house flies," said Dana Nayduch, a research leader and entomologist at the Arthropod-Borne Animal Diseases Research Unit, Center for Grain and Animal Health Research in Manhattan, KS.
"By looking at what flies are carrying within and on their bodies over time, we can directly assess what is going on in their surrounding environment on the farm, as they acquire those microbes from these sources all day, every day. In fact, if there is a sick animal on a farm, a fly is attracted to it and will find that needle in the haystack for you, potentially among thousands of animals, and feed upon it and collect its microbes in the process," explained Nayduch.
The insights gained from these ongoing studies can offer farm managers early warnings about the presence of harmful bacteria and viruses in their operations, enabling them to take preventive measures to protect cattle against potential severe illnesses or even outbreaks. back...
