An Alternative Approach to Fly Control: Vaccine Use in Organic and Conventional Dairy Herds
Location
John Q. Imholte Hall, Room #109
Event Website
https://2026undergraduateresearchsy.sched.com/event/2Ix84/an-alternative-approach-to-fly-control-vaccine-use-in-organic-and-conventional-dairy-herds
Start Date
15-4-2026 4:30 PM
End Date
15-4-2026 5:00 PM
Description
One of the challenges in modern dairy production is the control of external parasites, particularly flies, which cause discomfort and spread disease in cattle. Numerous management strategies exist; including sanitation, insecticides, feed additives, biological control, and topical sprays. Many are ineffective or prohibited in organic dairy systems, creating a significant need for alternative control methods. This study, conducted at the West Central Research and Outreach Center (WCROC) under Dr. Bradley Heins, evaluates the effectiveness of a horn fly vaccine developed by Medgene for use in both organic and conventional dairy herds. The vaccine is administered subcutaneously and works by introducing a cofactor into the cow’s bloodstream that is harmless to the animal but causes blood coagulation within the fly upon feeding, ultimately resulting in fly mortality. Cattle across multiple life stages (calves, heifers, lactating cows, and dry cows) were vaccinated in mid-May. Fly populations were monitored weekly immediately after vaccination through mid-October and compared between vaccinated and unvaccinated control groups. Counts included horn flies as well as other common fly species affecting dairy cattle. Flies were counted once a week after 11am, counts were estimated in groups of ten based on the fly presence directly on the cow at the time. The first trial is completed and analysis is ongoing, right now we have a rough estimate of a 40% decrease in flies. Our research aims to assess the vaccine’s potential as an effective and efficient approach to fly control. If successful, this new approach will be a significant advancement to fly management, especially for organic dairy producers.
Publication Date
2026
An Alternative Approach to Fly Control: Vaccine Use in Organic and Conventional Dairy Herds
John Q. Imholte Hall, Room #109
One of the challenges in modern dairy production is the control of external parasites, particularly flies, which cause discomfort and spread disease in cattle. Numerous management strategies exist; including sanitation, insecticides, feed additives, biological control, and topical sprays. Many are ineffective or prohibited in organic dairy systems, creating a significant need for alternative control methods. This study, conducted at the West Central Research and Outreach Center (WCROC) under Dr. Bradley Heins, evaluates the effectiveness of a horn fly vaccine developed by Medgene for use in both organic and conventional dairy herds. The vaccine is administered subcutaneously and works by introducing a cofactor into the cow’s bloodstream that is harmless to the animal but causes blood coagulation within the fly upon feeding, ultimately resulting in fly mortality. Cattle across multiple life stages (calves, heifers, lactating cows, and dry cows) were vaccinated in mid-May. Fly populations were monitored weekly immediately after vaccination through mid-October and compared between vaccinated and unvaccinated control groups. Counts included horn flies as well as other common fly species affecting dairy cattle. Flies were counted once a week after 11am, counts were estimated in groups of ten based on the fly presence directly on the cow at the time. The first trial is completed and analysis is ongoing, right now we have a rough estimate of a 40% decrease in flies. Our research aims to assess the vaccine’s potential as an effective and efficient approach to fly control. If successful, this new approach will be a significant advancement to fly management, especially for organic dairy producers.
https://digitalcommons.morris.umn.edu/urs_event/2026/oralpresentations/10