Buffalo flies love the warm moist weather
10 December 2015
North Coast Local Land Services District Veterinarians have advised landholders that the recent warm moist weather has seen an increase in buffalo fly numbers on the North Coast. The buffalo fly, despite its small size, can have a significant impact on the productivity of cattle.
The buffalo fly feeds on the blood of the cow and causes irritation which can result in reduced production if the cattle are heavily infested. In a beef herd it is generally considered that infestations of more than 200 flies per animal (100 on each side) are necessary to reduce production. In dairy cattle infestations above 30 flies were estimated to cause losses in milk production and live weight gain.
Some cattle are allergic to the buffalo flies and are intensely irritated by as few as four or five flies.
Allergic cattle scratch and rub themselves constantly which results in large sores on their necks and sides. The value of the hide is also reduced when cattle have developed skin sores as a result of buffalo fly infestation.
Some of the skin sores seen on cattle can be attributed to a small, worm like parasite that causes a circumscribed dermatitis. It is thought that the buffalo flies transmit the worm between animals.
Liz Bolin, District Veterinarian said, "It is recommended that producers apply an integrated management program for the control of buffalo flies.
"The aim of such a program is to enable producers to reduce fly numbers to acceptable levels for efficient production without compromising on animal welfare, chemical residues and chemical resistance."
Chemical control options include Synthetic pyrethroids (SPs), Organophosphates (Ops) and Macrocyclic lactons (MLs). These chemicals can be applied via impregnated plastic ear tags, sprays, Pour-ons, plunge dips or back rubbers.
Chemical resistance can occur when chemicals are mixed or applied at lower than recommended concentrations or dose rates, or when insecticidal ear tags are not removed at recommended times.
Liz continued, "To prolong the effectiveness of the chemical groups and minimise residues strictly adhere to the dosing schedules and the WHPs on the product label.
It is recommended that you do not use a product from the same chemical group year in, year out, instead rotate your chemical use." Liz concluded.
Non chemical control options available include buffalo fly traps, culling allergic cattle and dung beetles.
If you have any questions regarding buffalo flies please contact your North Coast Local Land Services District Veterinarian or your local vet.
Media contact: Liz Bolin, District Veterinarian, 0412 303 907Photo captions: Cows can be significantly impacted by buffalo fly at this time of year.