Controlling Horn Flies - Uaex.edu
Agriculture and Natural ResourcesFSA7031Controlling Horn Flies on CattleKelly M. LoftinAssociate Professor andExtension EntomologistRicky F. CorderProgram Associate EntomologyArkansas IsOur CampusVisit our web site , the horn fly,Haematobia irritans irritans (L.), isthe most important arthropod pest ofpastured cattle in the United States(Byford et al. 1992). Losses in theUnited States have been estimated atabout 800 million annually. Theselosses are greatest to lactating cowsand growing calves. High horn flypopulations cause both significantblood loss and annoyance. Annoyanceresults in energy losses associatedwith combating the flies, changesand/or reductions in routine grazingpatterns and bunching of animals.Significant reduction in calf weaningweights is well documented. This lossis related to a decline in milkproduction as a result of horn flyfeeding or annoyance. Studies haveshown that effective horn flymanagement can result in a 15 30pound increase in weight in stockercalves during the growing season.University of Arkansas researchersnoted a 17 pound reduction in calfweaning weights for every 100 fliesfeeding on the cow.Horn flies have long beenimplicated in the spread of summermastitis in non lactating mammaryglands. Louisiana State Universityresearchers identified a link betweendairy heifers with Staphyloccusaureus mastitis and horn flies.Subsequent research suggested thatthey are at a higher risk of acquiringmastitis when horn fly populationsexceed 50 100 per animal. The hornfly can also serve as an intermediateFigure 1. Horn fly feeding on a cow.(Craig Sheppard, University of Georgia,Bugwood.org)host of Stephanofilaria stilesi, anematode that causes skininflammation along the belly of cattle.Although the horn fly is primarily apest of cattle and requires cattle dungfor development, it will occasionallyfeed on other mammals such ashorses, sheep, goats and dogs.BiologyThe horn fly was accidentallyintroduced into the U.S. from southernFrance prior to 1886. This small fly(Fig. 1) (approximately 1/8 inch long)is about half the size of a house flyand is known for spending most of itstime on the back, head and shouldersof its host (Fig. 2). During very hot orrainy weather, horn flies may move tothe belly. In addition to being smallerthan the house fly, horn flies can bedifferentiated by their piercingmouthparts that resemble a beak.Horn flies only leave the animal to layeggs on fresh cattle manure, less than10 minutes old. Both sexes feed oncattle by taking 20 to 40 blood mealsper day. Populations of up to 10,000University of Arkansas, United States Department of Agriculture, and County Governments Cooperating
Figure 2.Figure 3.(above)Horn flies on the back, neck and shoulders of a bull.Figure 4a. Illustration of a cowwith 50 horn flies.(right) Development of horn flies in fresh manure. (Art Cushman, USDA;Property of the Smithsonian Institution, Department of Entomology, Bugwood.org)per animal have been documented but normally donot reach this extreme. Development from egg toadult occurs in as little as 9 12 days. Eggs hatch andlarvae develop within the manure (Fig. 3). Maturelarvae migrate to the lower portion of the manure pator in the soil to pupate. Adults emerge after about5 or 6 days. Horn flies mate and seek a host to beginblood feeding a couple of days after emergence. Anadult female may begin laying eggs three days afteremergence and may lay up to 400 eggs during herlifetime. With such a short life cycle, manygenerations per year are possible, making it a verygood candidate to develop insecticide tolerance,especially in southern areas.achieved by counting the number of horn flies on thehead, shoulders and back of at least 10 cattle(10 to 15). Whole body counts are the most accuratebut in practice are difficult to make. Counting thenumber of flies on one side of an animal may be theonly option available. Horn fly counts from at least 10animals should be used to produce an average. Whenaverage counts approach the economic threshold(150 200/head for beef or 75 100/head for dairy),control or supplemental control should be considered.Figure 4a c illustrates horn flies on cattle and may behelpful in estimating fly numbers.Horn flies survive the winter as pupae in the soil.Adults emerge in mid March with populationspeaking in late May or early June. Horn fly presenceor absence is temperature dependent, whileabundance is influenced by humidity andprecipitation. Therefore, during the dry and hotmonths of summer, populations normally decrease. InSeptember, as temperature decreases and humidityand rainfall increase, populations will peak again.Walk-Through Horn Fly TrapControlThe walk through (Bruce) trap (Fig. 5) will helpcontrol horn flies by dislodging the flies as the animalpasses through the trap. Dislodged flies are trappedin elements located on the sides of the trap. Trappedflies cannot escape and die from starvation ordehydration. The animals must pass through theEconomic Injury Level andHorn Fly MonitoringMonitoring horn fly abundance on cattle isimportant in making appropriate managementdecisions. Routine monitoring will help producersdetermine when best to initiate control methods andthe efficacy of the current control program. It willalso provide early warning to potential insecticidetolerance or other issues that negatively impactcontrol.Horn fly abundance should be monitored weeklythroughout the fly season. Monitoring is bestFigure 5. Walk-through (Bruce) trap dislodges andcaptures horn flies as the cattle pass through.
Figure 4b. Illustration of a cowwith 100 horn flies.trap to provide control; therefore, the traps areusually located in an area where animals must passto gain access to water and/or feed, or in the case ofdairy cattle, to travel to the milking parlor. Duringwet years, observe cattle to confirm use of the trap, asalternative sources of water may be available for theanimals to drink; decreased use of traps will reducetheir effectiveness for horn fly control.In one Arkansas trial, an overall reduction of 57percent of horn flies was noted when compared to anuntreated herd. In another trial, the traps helpedreduce the frequency of insecticide applications by 50to 75 percent. Consult your county Extension agentfor plans on building these traps.Insecticide-Impregnated Ear TagsInsecticide impregnated ear tags areapplied to the ears ofcattle and release a smallamount of insecticideover a long period of time(Fig. 6). If used properly,they can be an effectivetool for controlling hornflies and ear ticks [suchas the Gulf Coast tick,Ambylomma maculatumKoch, and the Spinoseear tick, Otobius megnini(Duges)] and may reduceface fly, MuscaFigure 6. Insecticidal earautumnalis DeGeer,tags being applied tonumbers. Ear tags cancattle.provide about 12 to 15weeks of continuous horn fly control.The active ingredients of ear tags now fall intofive broad chemical categories: synthetic pyrethroid,organophosphate, organochlorine (cyclodiene),macrocyclic lactone and mixtures of the syntheticpyrethroid and organophosphate insecticides. InFigure 4c. Illustration of a cowwith 200 horn flies.addition to the active ingredient, several ear tagscontain a synergist such as piperonyl butoxide thatincreases insecticide toxicity to the horn fly.Since the advent of insecticide impregnated eartags in the early 1980s, some horn fly populations inthe southern states have developed resistance to theinsecticides used in the tags, especially to syntheticpyrethroid and organophosphate ear tags, which formany years were the only insecticide classes used ininsecticidal ear tags. Insecticide resistance ortolerance occurs because of the horn fly’s shortgeneration time (every 2 weeks) and multiplegenerations (more than 10) per year coupled with thelong residual activity of insecticide impregnated eartags. If ear tags are going to be used, a fewsuggestions should be followed to help optimizeeffectiveness.1. Base ear tag application on the horn flypopulation and economic threshold (150 200 peranimal for beef cattle and 75 100 per animal fordairy cattle). If ear tags are applied too early, theymay fail late in the season because of normal lossof insecticide activity.2. Target control to get the most of your application.For example, treatment of lactating animals willhelp maintain calf weaning weights.3. Rotate insecticide classes. Do not use the sameinsecticide class year after year. Instead rotateamong synthetic pyrethroid, organophosphate,organochlorine and macrocyclic lactone insecticideclasses. Remember, not all insecticide ear tags orclasses are labeled to use on lactating dairycattle. Consult MP144, InsecticideRecommendations for Arkansas, for a listing ofinsecticide impregnated ear tags.4. Remove insecticide ear tags when they are nolonger effective, when the label recommendsremoval or in the fall.
5. Read the label; don’t rely on ear tag colors ornames to determine insecticide class. Differentbrand names of tags may contain the same activeingredient. The label usually suggests how manytags to use per animal. For face fly suppressionand control of ear ticks, one tag per ear (two peranimal) is more effective.when passing through a gateway (Fig. 8). Whencharging or recharging a back rubber, use a goodgrade mineral or fuel oil (not motor oil) to mix withthe insecticide. Mix the oil/insecticide solutionaccording to label instructions.6. Consider other control methods such as self treatment devices, sprays, mechanical trapping,feed additives or pour on insecticides.Animal activated sprayers are similar to self treatment devices in that the animal is treated on itsway to or from a food or water source (Fig. 9). In mostdevices, the insecticide is sprayed onto the animalwhen the animal triggers a switch or electronic eye.These are used in gateways leading to minerals orwater or as an exit sprayer in a dairy facility.Generally, only a small amount (less than 2 ounces)of insecticide is applied to the animal per application.Normally, animal activated sprayers are only turnedon when the fly population exceeds a predeterminednumber (i.e., 100 150 horn flies per animal)indicating that routine monitoring of the horn flypopulation is necessary. Transportable, solar powereddevices are available commercially.Self-Treatment DevicesIf properly used and maintained, self treatmentdevices such as dust bags and backrubbers can be aneffective and economical horn fly control technique.These devices allow cattle to treat themselvesespecially when they are forced use (moving througha restricted area on their way to feed or water).Specific synthetic pyrethroid and organophosphateinsecticide dust and liquid formulations are labeledfor use in dust bags, back rubbers and animalactivated sprayers. Consult MP144, InsecticideRecommendations for Arkansas, for a listing oninsecticides labeled for use in backrubbers ordust bags.Dust BagsForced use dust bags can be a very effective hornfly control method (Fig. 7). Insecticide dust is appliedto the animal as it passes through an opening such asa gateway. Dust bags are constructed of close meshfabric bags (usually heavy canvas or burlap andavailable commercially from most farm or feedoutlets) that contain an insecticide dust. Inspect dustbags regularly and recharge with insecticide dustwhen needed. Dust bags should be kept dry to reduceinsecticide clumping and loss of effectiveness.Animal-Activated SprayersCattle often require acclimation to these animal activated sprayers before they will routinely use thedevice. The device is usually placed in the off positionin a gateway that animals must pass through for foodor water. After cattle easily pass through the devicein the off position, it can be turned to the on positionso that cattle become accustomed to being sprayed.The acclimation process may take a week or longer.Insect Growth Regulators and LarvicidesBack rubbers are used in much the same way asdust bags. A small amount of oil/insecticide solutionis applied to the animal as it rubs under the deviceInsect growth regulators (IGR) and larvicidesprevent horn fly larvae from developing into adults.These are administered to cattle as feed additives;immature horn flies (maggots) are exposed to thesechemicals in the manure of cattle which consumedthe product. Some formulations are available ready to feed, in the form of protein or mineral blocks ortubs, while others will require top dressing or customblending. One IGR is available in a bolus labeled toprovide larval control for up to 150 days. The mode ofaction of larvicides and IGRs differs. IGRs disruptFigure 7. Forced-use dust bags.Figure 8. Insecticide-charged back rubbers.Back Rubbers
Figure 9b. Solar-powered automaticsprayer.Figure 9a. Battery-poweredautomatic sprayer.normal molting and development of immature hornflies (maggots) whereas larvicides are traditional toxinsthat kill the maggots.Use of IGRs or larvicides is normally initiated justprior to the first appearance of horn flies in the springand throughout the summer and fall until cold weatherrestricts fly activity. Proximity to untreated herds andadequate consumption by cattle are two factors that canlead to variable results. To be effective, cattle mustconsume a specified amount, preferably on a dailybasis. If consumption is below the specified rate, eitherincrease the number of feeding stations or relocatestations to areas more frequented by cattle. Likewise, ifconsumption rate is above the specified rate, eitherdecrease the number of feeding stations or relocatestations to areas less frequented by cattle. Supple mental control measures may be required if horn fliesare moving in from untreated herds located nearby.Diflubenzuron and methoprene are examples of IGRs;tetraclorvinphos is an example of a larvicide. Theseproducts demonstrate similar effect on other flies (suchas face flies) developing in cattle manure. ConsultMP144, Insecticide Recommendations for Arkansas, foradditional information on larvicides and IGRs.Pour-On InsecticidesPour on insecticides are ready to use formulationsapplied along the back line of cattle at a dose based onbody weight (Fig. 10). The concentration of theinsecticide in a pour on is usually higher than the finalconcentration used in a spray solution. Rates varydepending upon the insecticide formulation but usuallyrange from 0.5 to 2 ounces per animal. Most conven tional pour on insecticides used against horn flies areformulated from synthetic pyrethroids. However, aFigure 10. Pour-on insecticide application.few pour on insecticides, macrocyclic lactones(ivermectin, etc.), are formulated to control internalparasites as well. Reliance on pour on macrocycliclactones alone for horn fly control should be limited tolessen internal parasite tolerance issues. Pour oninsecticides will normally provide control from 2 to 4weeks following application. Consult MP144, InsecticideRecommendations for Arkansas, for additionalinformation on pour on insecticides.Insecticide SprayingHigh volume,high pressureresidual insecticidespraying is effectivein controlling hornflies and othercattle pests(Fig. 11). About 1 to2 quarts of aninsecticide solutionFigure 11. High-volume, high-pressureis applied with ainsecticide spray application.power sprayer at apressure of 150 200 psi. This amount and pressure will provide nearcomplete coverage and penetration to the animal’s skin.One drawback to high pressure spraying is theincreased cattle handling required to make multipleapplications throughout the fly season. Low pressure,low volume spraying with hand held sprayers can beeffective for some producers with gentle animals. Withlow pressure, low volume spraying, the applicatorwalks or drives around cattle applying an insecticidesolution on an as needed basis. Insecticide concentrateslabeled to mix with water and apply to cattle primarilyinclude the synthetic pyrethroid, organophosphate andspinosyn classes. Consult MP144, InsecticideRecommendations for Arkansas, for additionalinformation on insecticide concentrates.
ReferencesByford, R.L., B. Cosby and M.E. Craig. 1992. A reviewof ectoparasites and their effect on cattleproduction. Journal of Animal Science 70: 597 602.Johnson, D.R., G. Lorenz, G. Studebaker, J.D.Hopkins. 2001. Horn Flies on Beef Cattle.FSA7031. Univerisity of Arkansas Division ofAgriculture CES.Printed by University of Arkansas Cooperative Extension Service Printing Services.DR. KELLY LOFTIN, associate professor and Extensionentomologist, and RICKY F. CORDER, program sssociate entomology, are with the University of Arkansas Division ofAgriculture. Loftin and Corder are located at the Cralley WarrenResearch Center in Fayetteville.FSA7031 PD 12 09RVIssued in furtherance of Cooperative Extension work, Acts of May 8 andJune 30, 1914, in cooperation with the U.S. Department of Agriculture,Director, Cooperative Extension Service, University of Arkansas. TheArkansas Cooperative Extension Service offers its programs to all eligiblepersons regardless of race, color, national origin, religion, gender, age,disability, marital or veteran status, or any other legally protected status,and is an Affirmative Action/Equal Opportunity Employer.
adult occurs in as little as 9 12 days. Eggs hatch and larvae develop within the manure (Fig. 3). Mature larvae migrate to the lower portion of the manure pat or in the soil to pupate. Adults emerge after about 5 or 6 days. Horn flies mate and seek a host to
Horse fly Horse fly Horse fly Horse fly Horse fly Deer fly Tabanid flies Tabanids: Horse Flies and Deer Flies (multiple species) Description and Biology. The tabanids are a group of flies that include the deer flies and horse flies. Deer flies are the smaller flies ranging in size from 1/4 to 3/8 inch in length. They are yellow-
Keyword Index: Horse flies, deer flies, biting fly, yellow flies, attractants. INTRODUCTION courses, campgrounds, fishing areas, and recreation areas used for The family Tabanidae includes horse flies, deer flies, and yellow flies, all of which have veterinary and medical importance. Large tabanid populations have a significant economic impact
Horn Flies, Stable Flies, House Flies, Horse Flies, Deer Flies, Mosquitoes and Gnats, apply Farnam Equine Fly Repellent 397'as directed below. As a spray: Remove excess dirt and dust. Apply a light spray mist sufficient to wet the surface of the hair while brushing lightly against the lay of the hair. Avoid spraying in eyes and mucous membranes.
Oct 26, 2009 · Horse Stables: To Kill stable flies, hom flies, houseflies, face flies, horse flies, deer flies, mosquitos and gnats: Apply thoroughly to surfaces until wet. Insects coming to rest on treated surfaces will be killed or repelled. Do not treat more than once per week. Do not spray animals
Northern foul mites 10% Chiggers 10% Soldier flies 10% Bed bugs 10% Depluming mites 9% Lice 9% Fowl ticks 8% Table 3. Difficulty of controlling pests. Pest Ranking Fire ants 3.3 Darkling beetles 2.8 Black flies 2.7 House flies 2.7 Mice 2.6 Rats 2.4 Varmints 2.0 Mosquitoes 2.0 Soldier flies 1.7 Chicken mites
the previous summer and fall by a horn fly infestation. Horn fly allergy (allergic dermatitis) During the horn fly season, cattle often develop a skin allergy to the saliva of the biting horn flies. After several weeks, an inflammatory reaction occurs in the skin, and many hair follicles are destroyed.
Lord of the Flies has been called “a fable in which the characters are symbols for abstract ideas.” Literal level: Lord of the Flies deals with what happens to a group of boys stranded on an island with no adult supervision. Symbolic level: Lord of the Flies investigates what happens to civilized people when the structures of civilization
Certification Standard Animal Nutrition – V5 for January 2020 P a g e 7 81 Daily ration: Average total quantity of feedingstuffs, calculated on a moisture content of 12 %, required daily by an animal of a given species, age category and yield, to satisfy all its needs (Regulation 1831/2003).
