Buffalo flies, Haematobia irritans exigua, are similar to horn flies in size and appearance and in feeding and breeding habits. The buffalo fly is a primary pest of cattle and water buffalo but occasionally feeds on horses, sheep, or wildlife. It is distributed throughout northern Australia and New Guinea and is found in parts of southern, southeastern, and eastern Asia as well as Oceania; it is not found in New Zealand.
The buffalo fly's life cycle is similar to that of the horn fly; the adult leaves the host long enough to oviposit on fresh manure, where development occurs. The life cycle can take as few as 7–10 days, depending on weather conditions.
Pathology of Buffalo Flies of Cattle
Buffalo flies irritate and annoy animals, usually biting about the shoulders and withers. Both sexes feed on blood 20–40 times per day (1). Bite wounds can provide a site for screwworm (Chrysomya bezziana) infection. During hot weather, the flies move to shaded parts of the body.
Affected animals suffer blood loss and are irritated by the flies; feed efficiency and production can be notably affected with even 100 flies per animal. Some cattle are allergic to the fly saliva. Dark-colored cattle and those in poor condition attract more flies.
Diagnosis of Buffalo Flies of Cattle
Buffalo flies can be identified by their dark color, size (approximately half that of a stable fly), and bayonet-like proboscis that protrudes forward from the head. Buffalo flies stay permanently on cattle and leave only if disrupted or to breed and deposit eggs into dung. (See images of and heavy infestation in and a . See also image of . )
Top: buffalo fly infestation (Haematobia irritans exigua) on a cow in Laos; bottom: close-up of infestation.
Top: buffalo fly infestation (Haematobia irritans exigua) on a cow in Laos; bottom: close-up of infestation.
Courtesy of Nichola Calvani, Laboratory of Veterinary Parasitology, Sydney School of Veterinary Science, The University of Sydney.
Cows in Queensland, Australia, with heavy buffalo fly burden.
Cows in Queensland, Australia, with heavy buffalo fly burden.
Courtesy of Anthony Feez.
Bull in Queensland, Australia, infested with a heavy burden of buffalo flies.
Bull in Queensland, Australia, infested with a heavy burden of buffalo flies.
Courtesy of Anthony Feez.
Traumatic lesions (blue arrows) as consequence of buffalo fly infestation in cattle in Queensland, Australia, with buffalo fly burden.
Traumatic lesions (blue arrows) as consequence of buffalo fly infestation in cattle in Queensland, Australia, with buff
Courtesy of Anthony Feez.
Cattle in Queensland, Australia, with buffalo fly burden.
Cattle in Queensland, Australia, with buffalo fly burden.
Courtesy of Anthony Feez.
Cattle in Queensland, Australia, bunching up to escape buffalo fly burden.
Cattle in Queensland, Australia, bunching up to escape buffalo fly burden.
Courtesy of Anthony Feez.
Cattle in Queensland, Australia), flushing the fly burden.
Cattle in Queensland, Australia), flushing the fly burden.
Courtesy of Anthony Feez.
Video of fly worry behaviors in cattle in Queensland, Australia, with buffalo fly burden.
Courtesy of Anthony Feez.
Top: buffalo fly infestation (Haematobia irritans exigua) on a cow in Laos; bottom: close-up of infestation.
Top: buffalo fly infestation (Haematobia irritans exigua) on a cow in Laos; bottom: close-up of infestation.
Courtesy of Nichola Calvani, Laboratory of Veterinary Parasitology, Sydney School of Veterinary Science, The University of Sydney.
Cows in Queensland, Australia, with heavy buffalo fly burden.
Cows in Queensland, Australia, with heavy buffalo fly burden.
Courtesy of Anthony Feez.
Bull in Queensland, Australia, infested with a heavy burden of buffalo flies.
Bull in Queensland, Australia, infested with a heavy burden of buffalo flies.
Courtesy of Anthony Feez.
Traumatic lesions (blue arrows) as consequence of buffalo fly infestation in cattle in Queensland, Australia, with buffalo fly burden.
Traumatic lesions (blue arrows) as consequence of buffalo fly infestation in cattle in Queensland, Australia, with buff
Courtesy of Anthony Feez.
Cattle in Queensland, Australia, with buffalo fly burden.
Cattle in Queensland, Australia, with buffalo fly burden.
Courtesy of Anthony Feez.
Cattle in Queensland, Australia, bunching up to escape buffalo fly burden.
Cattle in Queensland, Australia, bunching up to escape buffalo fly burden.
Courtesy of Anthony Feez.
Cattle in Queensland, Australia), flushing the fly burden.
Cattle in Queensland, Australia), flushing the fly burden.
Courtesy of Anthony Feez.
Video of fly worry behaviors in cattle in Queensland, Australia, with buffalo fly burden.
Courtesy of Anthony Feez.
Cattle infested with buffalo flies commonly respond by tail swishing, kicking at the abdomen with the hind limbs, licking the back, and twitching the skin of the flanks. Such defensive behaviors are characteristic of biting fly attack and, in pastured cattle, are often indicative of buffalo fly infestation. (See images of ; ; and . See also the .)
Treatment and Control of Buffalo Flies of Cattle
Integrated pest management
Insecticidal ear tags
Treatment and control are as in horn flies. Insecticides are only one part of integrated pest management (IPM) programs for buffalo fly populations that exploit the biology and behaviors of the flies. Registered insecticidal ear tags are recommended for peak fly season from late summer to early autumn. Cattle producers need to be aware of withholding periods and observe export slaughter intervals. Many of the chemicals used to treat these flies leave residues in meat.
Buffalo fly traps and tunnel traps have been developed in Australia. Each trap consists of a rounded, clear plastic tent through which the cattle walk. The flies are brushed off the cattle within the tent and are then trapped inside, where they die of desiccation. These traps remove approximately 80% of the buffalo flies each time the cattle pass through (2). When cattle pass through the trap every day or every second day, sufficient fly control is usually achieved. Other nonchemical controls include fly traps, use of dung beetles disrupting the larval development by breaking up the manure piles, and culling highly sensitive cattle.
In Australia, management of the buffalo fly follows principles similar to those used for horn flies. Widespread and often high-level resistance to synthetic pyrethroids has been documented (3), resistance to organophosphates is well established in many regions, and concerns about decreased efficacy of macrocyclic lactones have emerged in the field. Consequently, reliance on any single chemical class is unlikely to provide sustainable long-term control.
Effective buffalo fly management relies on IPM approaches, including rotating insecticides with different modes of action to delay resistance selection, implementing mechanical control methods such as tunnel traps, breeding cattle with increased natural resistance, and conserving beneficial dung beetle populations.
As with horn flies, treatment decisions should be guided by economic thresholds rather than routine calendar-based treatments. Delaying treatment until infestation exceeds 200 flies per animal in beef cattle (30 flies per animal in dairy cattle) can decrease insecticide use, slow resistance development, and improve the sustainability of buffalo fly control programs (4).
For More Information
Buffalo fly. FlyBoss.
Flies. Meat & Livestock Australia.
Also see pet owner content regarding flies and mosquitoes of dogs, cats, and horses.
References
Brewer GJ, Boxler DJ, Domingues LN. Horn fly (Diptera: Muscidae)—biology, management, and future research directions. J Integr Pest Manag. 2021;12(1):42. doi:10.1093/jipm/pmab019
Beatty D. Evaluation of a buffalo fly trap on two Queensland beef properties. Project number NBP.312. Meat and Livestock Australia; 2002. https://www.mla.com.au/research-and-development/reports/2002/evaluation-of-a-buffalo-fly-trap-on-two-queensland-beef-properties/
Schroder J. Monitoring of insecticide resistance in field sampled buffalo flies. Project number AHW.003. Meat and Livestock Australia; 2000. https://www.mla.com.au/research-and-development/reports/2000/monitoring-of-insecticide-resistance-in-field-sampled-buffalo-flies/
Manage pesticide resistance for cattle. FlyBoss. https://flyboss.com.au/manage-pesticide-resistance/
