Assessing the effects of house fly (Diptera: Muscidae) nuisance activities on cattle feeding behavior by use of a custom feeding box

Authors: Pitzer Jr, Jimmy; FIGUEROA-ZAMUDIO, JESUS - New Mexico State University; WALKER, HANNAH - New Mexico State University; SANCHEZ-SANDOVAL, ULISES - New Mexico State University; SMYTHE, BRANDON - New Mexico State University

Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/9/2026
Publication Date: 3/26/2026
Citation: Pitzer Jr, J.B., Figueroa-Zamudio, J.J., Walker, H., Sanchez-Sandoval, U.A., Smythe, B.G. 2026. Assessing the effects of house fly (Musca domestica; Diptera: Muscidae) nuisance activities on cattle feeding behavior by use of a custom feeding box. Journal of Medical Entomology. https://doi.org/10.1093/jme/tjag047.
DOI: https://doi.org/10.1093/jme/tjag047

Interpretive Summary: House flies are common nuisance pests that pose a significant threat to livestock, particularly cattle, due to their role in transmitting numerous pathogens such as those that cause viral diarrhea, pinkeye, and bovine respiratory disease. House fly driven economic losses to animal agriculture in the U.S. are estimated to be $1 billion annually, but this estimate currently is associated with the costs of controlling this pest and treating the diseases caused by its activity. Conversely, research has shown that the irritation caused by other pest flies, such as the blood-feeding stable fly, results in decreased weight gains and milk production in cattle, with losses in the U.S. of more than $2 billion annually. These losses are attributed to defensive behaviors that divert feed intake energy otherwise used for growth and milk production to activities such as tail tossing, head throwing, and foot stomping. Therefore, the current economic costs to the U.S. cattle industry due to house fly activity likely are grossly underestimated, as they fail to capture the added damage caused when house flies cause defensive behaviors in cattle. To begin bridging this knowledge gap, we exposed angus heifers to 1,000 house flies during a 5-min feeding period. Heifers exposed to house flies demonstrated significantly more defensive behaviors than those heifers that fed under undisturbed conditions. This is the first study, in over a century to suggest that house flies elicit undesirable behavioral effects in feeding cattle that may cause previously unrecognized economic losses for producers. Our results should therefore serve as a primer for further research that unlocks the true costs of house fly populations associated with cattle production.

Technical Abstract: To date, the economic impact of adult house fly activity on cattle production is limited largely to costs associated with managing house fly populations and treating diseases associated with pathogens they are known to transmit. However, anecdotal evidence suggests that house flies present in and around feed bunks may disrupt normal cattle feeding behavior. Eight angus heifers (~385 kg) were used in a crossover experimental design to determine the potential effect that adult house fly activity has on cattle feeding behavior. Heifers were acclimated to voluntarily using a custom, standalone box into which their head was enclosed while feeding. The acclimation period was followed by two 4-day observation periods, during which heifers were offered feeding boxes that were either infested with ~1,000 adult house flies or were uninfested. During each observation period, heifer behavioral responses were recorded, including tail tosses, skin twitches, foot-stomping, feeding hesitation, as well as the weight of any remaining feed not consumed (grain refusal). Although no significant differences in leg stomping or resultant grain refusal occurred between treatment groups, the frequency of tail tosses, skin twitches, and feeding hesitation were significantly higher when flies were present in feeding boxes than when feeding from uninfested boxes. These findings suggest that house fly activity at the feed bunk causes a level of discomfort among heifers that results in feeding disruption and therefore may account for a previously unrecognized source of economic loss for cattle producers.