Integrated Pest Management (IPM) for Mosquitoes on Dairy, Livestock, and Horse Farms

Recent outbreaks of equine encephalitis highlight the urgent need for effective mosquito control measures on farms. This disease is primarily transmitted by mosquitoes, with the black-tailed mosquito, Culiseta melanura, serving as a significant vector. Found from the Midwest to the East Coast, Culiseta melanura typically produces two generations per summer. The virus is maintained through a natural cycle involving birds and mosquitoes, but other mosquito species can also transmit it after feeding on an infected host. Controlling Culiseta melanura is challenging due to its preferred habitat of swamps, which are difficult to manage. Additionally, since other potential mosquito vectors require aquatic environments for reproduction, any standing water on a farm or near a home can become a breeding ground. Effective management should include regular monitoring and elimination of standing water, alongside integrated pest management (IPM) strategies, to reduce mosquito populations and the associated risk of equine encephalitis. For more information on Culiseta melanura please view the following site: https://edis.ifas.ufl.edu/publication/IN950#

.

Reducing Mosquito Breeding Sites

The most crucial step in mosquito control is limiting their breeding areas. Mosquitoes can lay eggs in any standing water, from small containers, puddles to large ponds. Here are some key areas to monitor and manage:

1. Old Tires: Tires used to secure silage pit plastic can collect water, providing a perfect breeding site. If using tires on the farm, ensure they are cut or drilled to prevent water accumulation.
2. Plastic from Hay or Haylage Bags: Discarded plastic can create pockets that collect rainwater, creating mosquito habitats. Dispose of or recycle old plastic properly to avoid this issue.
3. Manure Lagoons: While lagoons are essential for managing liquid manure, they can also become mosquito breeding sites. Properly constructed and maintained lagoons are less likely to support mosquito populations. Regularly remove weeds from the banks and edges to reduce their attractiveness to mosquitoes.
4. Waterers: Ensure that all waterers are regularly cleaned to remove organic material and replace the water frequently. Repair any leaks that may cause standing water to accumulate around waterers, as these can become breeding sites.
5. Barn and Barnyard Drainage: Proper drainage around barns is crucial. Ensure rainwater can drain away from the barns to avoid standing water. Gutters should be kept clear of organic debris that could cause water to pool.
6. Containers and Equipment: Old containers or equipment that collect water should be emptied or disposed of properly. Regularly inspect the farm for any items that could collect rainwater and create mosquito habitats.
7. Rainwater Barrels: While useful for water conservation, rainwater barrels can be ideal breeding grounds for mosquitoes. Empty these barrels weekly to disrupt the mosquito life cycle and prevent eggs from developing into larvae.
8. Natural Water Bodies: Ponds and swamps are natural habitats for mosquitoes and can be challenging to manage. While treatment options are available, they typically require a special DEC (Department of Environmental Conservation) permit and must be applied by a certified applicator.
9. Biological Control Options: Biological control for mosquitoes is limited but can be helpful as part of an IPM approach. Predators like birds, bats, and predatory insects feed on adult mosquitoes, but their impact is usually not sufficient to keep populations low due to the high reproductive rate of mosquitoes. For controlling larvae, Bacillus thuringiensis israelensis, a naturally occurring bacterium, that can only be used to control larvae in containerized waters in NYS. Make sure to follow label instructions.

Chemical Control Options

In cases of high mosquito populations, insecticide products may be necessary. It is essential to choose the right insecticide for the specific type of livestock. The VetPestX website provides a comprehensive guide to selecting and using insecticides for different livestock species, including the appropriate formulations and application methods. You can access VetPestX at VetPestX.

Vaccination and Consultation

Vaccination against mosquito-borne diseases like equine encephalitis is an essential part of disease prevention. Consult with your veterinarian for vaccination options and recommendations tailored to your farm’s needs.

By taking these steps, you can significantly reduce the mosquito population on your farm and help protect your livestock from mosquito-borne diseases. Remember, the key to mosquito control is vigilant monitoring and proactive management of potential breeding sites.

References:

DEC Pesticide Products to Control Mosquitoes

DEC Mosquito Control.

Eastern Equine Encephalitis (EEE)

Managing Mosquitoes on the Farm

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://anrcatalog.ucanr.edu/pdf/8158.pdf

Reducing the Risk of Mosquito Breeding on Farms

Black-Tailed Mosquito Culiseta melanura (Coquillett) (Insecta: Diptera: Culicidae)

https://edis.ifas.ufl.edu/publication/IN950#

Author: Ken Wise-NYSIPM, Cornell University, Dairy and Livestock IPM Coordinator

Managing pasture flies like horn and face flies through biological control is a sustainable and effective approach. In a healthy pasture ecosystem, natural predators and processes help keep fly populations in check, reducing the need for chemical interventions.

Dung Beetles (Scarabaeidae)

Dung beetles play a vital role in pasture ecosystems, particularly in managing manure and improving soil health. These beetles, part of the Scarab family, are known for their ability to bury manure, which not only recycles nutrients but also reduces the breeding grounds for pests like horn and face flies. By breaking down manure, dung beetles contribute to soil organic matter, improve soil structure, enhance water infiltration, and provide essential nutrients for grass growth.

There are approximately 90 species of dung beetles in North America, with a variety found in New York’s cattle pastures. These beetles are categorized into three main types based on their behavior:

Dwellers: These beetles live and reproduce within the manure pat, laying their eggs directly in or just beneath the soil surface. Dwellers are the most common dung beetles in the Northeast.

Photo By Hannah Tolz-NYS IPM

Tunnelers: Tunnelers create brood balls from manure and bury them in tunnels beneath the manure pat, laying their eggs within these buried balls.

Photo By Hannah Tolz-NYS IPM

Rollers: Rollers, though less common in New York, form brood balls and transport them away from the manure pat to bury them elsewhere, laying their eggs within these relocated brood balls.

Dung beetles are highly efficient at reducing fly populations by breaking down manure before flies can complete their life cycle.

To identify dung beetles in your pasture, flip over a manure pat with a small shovel or trowel and observe the beetles running around. Besides dung beetles, other beetle families such as rove, water, and hister beetles also inhabit dung pats and prey on fly larvae, further aiding in pest control.

Other Predators of Flies in Manure Pats

Several other beetle families contribute to fly control in pastures:

Rove Beetles (Staphylinidae): These versatile predators are found in various habitats, including manure pats, where they feed on fly larvae and other small insects.

Photo By Hannah Tolz-NYS IPM

Water Beetles (Hydrophilidae): Some species are specialized for life in manure pats, with larvae that prey on fly maggots.

Photo By Hannah Tolz-NYS IPM

Hister Beetles (Histeridae): These beetles thrive in manure and are efficient predators of fly maggots.

Photo By Hannah Tolz-NYS IPM

These beetles, alongside dung beetles, compete for manure resources and directly prey on fly maggots, significantly reducing fly populations.

For more information on Dung Beetles please view the following site: https://cals.cornell.edu/new-york-state-integrated-pest-management/eco-resilience/beneficial-insects/visual-guide-dung-beetles

Poultry and Wild Birds

Chickens can be an effective tool for fly control in rotational grazing systems. By introducing chickens into paddocks about four days after cattle have been rotated out, you give dung beetles time to work through the manure. Chickens then scratch through the pats, feeding on maggots and pupae, reducing fly populations while spreading the manure, which helps dry it out and eliminates breeding grounds. However, managing poultry requires additional effort.

Wild birds, like barn swallows and purple martins, also play a crucial role in fly control. These birds consume large numbers of flies during the breeding season, making them valuable allies. Encouraging a bird-friendly environment by installing and maintaining nesting boxes can help manage fly populations effectively.

Parasitoids

Parasitoid wasps are used to control stable and house flies around barns by infecting their pupae. However, face fly pupae are harder, making it difficult for parasitoids to penetrate them. Although a few parasitoids do infect horn fly pupae, research shows that augmentative releases are not very effective in pastures. Therefore, releasing parasitoids on pastures is not currently recommended. It’s better to reduce insecticide use until a herd reaches the action threshold to protect natural enemies.

Research is ongoing to improve biological control methods for horn and face flies in pastures, including the use of fungi and breeding cattle with greater fly resistance. By leveraging these natural behaviors and predators, farmers can maintain healthier pasture ecosystems and reduce their reliance on chemical controls.

Fly Resistance to Insecticides

Resistance to insecticides is a significant issue among livestock fly pests such as house flies, stable flies, horn flies, and face flies. These pests have developed resistance to many insecticides. To manage this resistance effectively:

1. Use Insecticides Only When Needed: Apply insecticides only when pest populations reach action threshold numbers specific to each fly species. This minimizes unnecessary insecticide use and helps delay resistance development.
2. Integrated Pest Management (IPM): Implement all non-insecticide control tactics alongside chemical treatments. Integrating various control methods can maintain lower pest populations without heavy reliance on insecticides.
3. Rotate Chemical Active Ingredients: Alternate insecticides with different active ingredients to prevent flies from developing resistance to a particular chemical. Always check and compare active ingredients before use.
4. Understand Modes of Action: Each insecticide’s mode of action (how it kills insects) is classified by the Insecticide Resistance Action Committee (IRAC). Using insecticides with different modes of action helps manage and reduce resistance. For more information, visit the IRAC website: IRAC Mode of Action Classification.

VetPestX: A Resource for Selecting Appropriate Insecticides

The VetPestX search engine is a useful tool for finding the right insecticide for your farming situation. It allows you to:

1. Select the type of livestock.
2. Choose the fly pest that needs control.
3. Specify the type of pesticide application and formulation.

Visit VetPestX (Pesticides for control of Insect Pests of Animals) here: VetPestX

By following these guidelines and utilizing resources like VetPestX, you can manage fly populations more effectively while mitigating the risk of insecticide resistance.

Coming next week-organic insecticides and repellents.

In 2017, the invasive longhorned tick (Haemaphysalis longicornis) (LHT) was found on a sheep farm in New Jersey. Since then, it has expanded its range into 21 states and D.C. LHT has been found as far north as Rensselaer County (2021), the farthest north the tick has been found. Only females have been found as LHT can clone themselves, meaning that a single female can quickly result in a large population.

Longhorn Tick (Haemaphysalis longicornis)

LHT is a major threat to livestock and possibly some species of wildlife. LHT occur at extremely high numbers when they infest livestock and wildlife, including cases where LHT have bled cows to death. There are cases of LHT vectoring bovine theileriosis, a cattle disease, in the U.S.

Source: https://www.aphis.usda.gov/livestock-poultry-disease/cattle/ticks/asian-longhorned/asian-longhorned-tick-what-you-need-know

Efforts have been made to assess the extent of LHT in New York through active surveillance. To bolster those efforts, we are asking those that own livestock, from producers to 4H club members, to report any suspected LHT on their farms at go.nysipm.org/report-lht. The form includes a few questions and allows you to upload a photograph of the tick. New York State Integrated Pest Management staff will follow up with you within a few days.

In an effort to keep the focus on livestock owners, we request that the reporting page not be shared with the general public.

If you have any questions, contact Joellen Lampman, Community IPM Extension Support Specialist, at jkz6@cornell.edu.

Last week, while conducting fly counts on pastures with beef cattle, I observed alarmingly high populations of face and horn flies on some of the animals. The action threshold for face flies is 10/face, but in some cases, there were more than 100 per animal. For horn flies, the threshold is 100 per side for beef cattle and 50 per side for dairy cattle; however, some cattle had well over the action threshold for horn flies.

Face Flies on Cattle

Horn Flies on Cattle

Horn flies typically reside on the back and sides of the cattle but move to the belly when it is very hot to escape the heat. Face flies are primarily found on the face of the cattle and are about double the size of horn flies. Horn flies can take up to 20-30 blood meals daily, causing extreme stress to the cattle. Face flies feed on secretions around the eyes and nose, as well as wounds and areas where biting flies have left openings.

To provide some perspective, there are approximately 75 horn flies within an 8-inch by 8-inch area on the animal. This indicates a significantly larger number of flies on the entire cow.

Depending on your management preferences, there are several options available to help control the fly populations:

• Dust Bags: Effective for applying insecticides as cattle pass under them.
• Back Rubbers and Oilers: Provide continuous insecticide application as cattle rub against them.
• Pour-ons: Easy to apply directly onto the cattle’s back.
• Insecticide Ear Tags: Long-lasting option that provides sustained fly control.
• Compressed Air Application (Vet Gun): Allows precise application of insecticides from a distance.
• Walk-Through Trap: Non-chemical option that physically removes flies as cattle pass through.
• CowVac: Sucks flies off the cattle as they pass through a chute.
• Oral Larvicides: Added to feed to prevent fly larvae from developing.

To find an insecticide, please use the following search engine: Veterinary Entomology Insecticide Search. Make sure to select NY to find the type of insecticide needed.

Each of these methods has its own advantages and can be selected based on your specific needs and preferences.

Horse and Deer Flies (Tabanidae spp.)

This year, there has been a noticeable increase in deer and horse fly populations. These flies inflict painful bites on mammals, including livestock and humans.

Female horse and deer flies possess sharp mouthparts that they use to cut through the skin of their hosts, lapping up the blood that flows from the wound. This biting behavior causes significant distress to livestock, especially when fly populations are high.

Photo By: Ward Strong, BC Ministry of Forests, Bugwood.org

Photo by: Sturgis McKeever, Georgia Southern University, Bugwood.org

Horse and deer flies are commonly found near tree lines and wet areas, as they thrive in aquatic and semi-aquatic habitats during their egg and larval stages. Most species prefer environments such as streams, ponds, or swamps, though some are found in wooded areas with abundant leaf litter. The development time from egg to adult varies widely among species, ranging from 90 days to several years.

Life Cycle

Horse and deer flies lay between 100 and 800 eggs on vegetation above wet areas. Upon hatching, the larvae drop into the water or moist ground below. Depending on the species, the larval stage includes 6 to 13 instars before pupation. These insects typically overwinter in the pupal stage.

Control Measures

Managing horse and deer fly populations on cattle is challenging due to the flies’ quick feeding habits. They land, cut open a spot, and take a blood meal rapidly, reducing their exposure to control measures. These flies often concentrate in specific areas on a farm.

For farms experiencing significant fly populations, various traps can be used to manage their numbers, including the Horse Pal, H-Trap, and Epps Trap. These traps have been found to be effective in certain situations. Placing traps in areas where flies are most prevalent can help reduce their numbers locally. It is essential to position the traps out in the open but away from cattle, as the animals may damage them.

By strategically placing traps and managing habitats, farmers can alleviate some of the issues caused by horse and deer flies, improving the well-being of their livestock and reducing the nuisance to humans.

Stable Flies 

Stable flies (Stomoxys calcitrans), known for their painful bites using piercing mouthparts, require blood to reproduce. This causes significant discomfort to cattle and, when populations are high, can reduce milk production in dairy cows, weight gains in calves and beef cattle. Both female and male stable flies feed on blood once or twice a day, typically targeting the legs of the cattle. However, when populations are high, they will feed on other parts of the animal as well.

Cattle under attack from large numbers of stable flies often show signs of distress, such as vigorously stomping their legs to dislodge the flies, which further impacts their feeding time, weight gains and milk production. Stable flies can infest cattle in both barns and pastures.

This video shows cattle moderately stomping off stable flies

Stable flies deposit their eggs in decomposing organic material and thrive in environments containing rotting moist grass, hay, straw, manure, and silage. They also lay eggs in lake weeds accumulating on banks, and any other decomposing materials leading to significant infestations, and can migrate long distances to find livestock.

A single female stable fly can lay up to 400 eggs and survive for about a month. Under optimal warm conditions, their lifecycle spans approximately 21 days from egg to adult. Once emerging as adults, they can take a blood meal within 12 hours.

Action Threshold

The action threshold for stable flies is a cumulative count of 10 flies on all four legs of an animal. Observing and counting flies on at least 10 to 15 cattle, then calculating the average, helps determine if intervention is necessary.

Management of Stable Flies

Sanitation: Proper sanitation is crucial for controlling stable flies. They lay eggs in moist, decaying organic matter. Breaking their lifecycle by regular cleaning is essential. Clean all moist organic matter from every corner of the barn, including stalls, calf hutches, pens, maternity areas, sick cow pens, under feeders, manure handling areas, and storage areas for feed, silage, and hay. Even a small amount of moist organic matter can produce hundreds of flies.

Composting: Composting manure, feed, old silage, hay, and bedding materials can kill fly eggs, maggots, and pupae. Compost piles reaching 120 degrees or more can effectively eliminate these stages of the fly. Turning the compost pile weekly prevents reinfestation by flies.

Spreading Manure and Bedding: Spreading manure, old bedding, silage, hay, and feed on a field in a thin layer allows the material to dry out, killing fly eggs and maggots in the decomposing organic matter.

Bedding Types: The type of bedding used can impact fly control. Moist straw mixed with manure, silage, hay, and feed is ideal for fly reproduction. Alternatives like sand, gravel, wood shavings, wood chips, and sawdust have lower fly reproduction rates. Nonetheless, regular cleaning of manure, feed, silage, and hay from stalls and pens is necessary.

Placement of Feed and Water: Placing feed and water outside of calf hutches, pens, and free-stall areas prevents contamination of bedding, reducing the risk of flies laying eggs.

Water Control: Preventing water from contacting bedding, hay, or feed is essential. Position waterers to avoid spillage, ensure proper drainage around barns, and direct rainwater away from buildings and feed storage areas. For calf hutches, mound gravel to ensure proper drainage and prevent moisture build-up. Adequate ventilation and dry conditions in calf hutches are also crucial.

Bedded Packs: For producers using bedded packs, it is essential to keep the area dry and add fresh bedding material regularly. Properly maintained bedded packs can minimize fly production.

Clean Hay/Haylage Feeders on Pastures: Stable flies breed in areas where hay or haylage accumulates on pasture. Clean these areas weekly to prevent significant fly production.

Biocontrol: One type of natural predator of fly pests is parasitoid wasps, which may already be present on farms. To enhance their impact, additional parasitoids can be purchased and released. By strategically releasing specific parasitoids in barn areas, the wasps act like “smart bombs” and target stable fly pupae.

For comprehensive insights into parasitoids targeting house and stable flies, please explore the following website: https://cals.cornell.edu/new-york-state-integrated-pest-management/outreach-education/fact-sheets/muscidifurax-raptor-and-m-raptorellus-biocontrol-agent-fact-sheet

Organic Solutions

For organic producers, approved forms of pyrethrum or neem and other natural repellents can offer some relief, though their efficacy may be limited to short durations.

Insecticidal Measures

Residual insecticides can be applied to barn walls to control stable fly populations. Flies resting on treated surfaces will be exposed to the insecticide. Various insecticidal products can also be applied directly to cattle to reduce fly pressure. VetPestX is a valuable resource for selecting suitable insecticides tailored to specific pasture conditions. More information can be found at VetPestX.

Horn fly populations are increasing rapidly this year, with some beef cattle exceeding the 200-fly action threshold. These flies cause significant pain and annoyance to dairy and beef cattle, leading to economic losses due to reduced milk production in dairy cattle and decreased weight gain in beef cattle.

Horn flies are biting insects that need a blood meal from cattle to reproduce, with both females and males consuming up to 30 meals daily. They are smaller, about half the size of face flies or stable flies, and primarily infest the back and sides of cattle, moving to the belly in higher temperatures. Horn flies spend most of their lives on cattle, leaving only to lay eggs in fresh manure. Each female can lay up to 20 eggs at a time, totaling around 400 in her lifetime. Maggots in manure can reach high populations.

The horn fly life cycle spans 10 to 20 days, with adults living about a month. They develop only in cattle manure pat on pasture, not in manure from other livestock. In the northeastern United States, there are typically 12 to 14 generations per grazing season.

To determine if control measures are needed, scout the cattle on pasture. Take photos of the cattle where the flies are, count the flies in that area, and estimate the number of horn flies on one side of the cattle. Depending on herd size, count up to 15 cattle, take the average, and compare it to the action thresholds.

Action Thresholds

• Dairy Cattle: 50 horn flies per shoulder, side, and belly.
• Beef Cattle: 100 horn flies per shoulder, side, and belly.

Control Methods

Bruce Trap (Passive Walk-Through Trap)

Horn flies, which dislike enclosed spaces, fly off the cattle as they enter the trap. The trap features strips of old carpet or canvas that brush off the flies, which then move towards the light and are trapped by double screen walls. Data suggests that this trap can control 50 to 70 percent of horn flies over time.

CowVac

The CowVac is an advanced vacuum system designed to remove horn flies from cattle. It generates a strong air current that dislodges flies from the cattle’s body, while a high-powered vacuum sucks up the dislodged flies. This trap has been shown to reduce horn fly populations on farms by 68%, improving cattle health and comfort and reducing the need for chemical treatments.

Flatten Manure Pats

Disrupting breeding habitats by flattening manure pats on pasture can control horn flies. Dragging a harrow or chain over the pasture spreads out fresh manure, causing it to dry out and preventing egg and larvae development. This method is particularly effective in rotational grazing systems but can be labor-intensive.

Shaded Areas

Providing shaded areas, such as sheds or barns, allows cattle to escape flies. Darkened spaces can significantly relieve cattle from the stress and annoyance caused by flies.

Organic Solutions

For organic producers, approved forms of pyrethrum or neem and other natural repellents can offer some relief, though their efficacy may be limited to short durations.

Insecticidal Measures

When infestations are significant, insecticides may be necessary. Use them only when populations exceed the action threshold. Methods include sprays, pour-on, ear tags, back rubbers, and dust bags, targeting areas where face flies congregate.

VetPestX is a valuable resource for selecting suitable insecticides tailored to specific pasture conditions, aiding producers in making informed choices. More information can be found at VetPestX.

Face Flies Already!

Yesterday, amidst our routine fly counts on beef cattle, we encountered a concerning influx of face flies. This year, their presence seems particularly pronounced, with some unfortunate animals bearing as many as 70 of these bothersome insects. Such numbers far surpass the accepted threshold of 10 flies per animal, prompting a heightened awareness of the potential issues they pose.

Resembling common house flies, female face flies predominantly target areas around the eyes and nose of cattle, as well as any wounds or cuts. Feeding on animal secretions, flower nectar, and dung liquid, these pests not only induce significant irritation but also serve as vectors for afflictions like pinkeye and Thelazia eyeworms.

Face Fly Video

The male face fly, primarily concerned with reproduction, spends little time directly on the cattle, preferring instead to perch on foliage, fence posts, and other surfaces. Meanwhile, the female deposits her eggs in fresh cattle manure, where they undergo a transformation from maggot to adult over a span of 2 to 3 weeks, depending on ambient temperature.

Maggot in a Dung Pat on Pasture

Combatting face flies requires a multifaceted approach:

1. Environmental Modifications: Face flies shy away from enclosed spaces, making the provision of sheds or barns a strategic move to offer relief during peak fly seasons.
2. Pasture Management: Regularly dragging or harrowing paddocks can disrupt the flies’ preferred breeding grounds, reducing their habitat and impeding their life cycle.
3. Organic Solutions: For organic producers, approved forms of pyrethrum and other natural repellents offer some relief, though their efficacy may be limited to short durations.
4. Insecticidal Measures: When faced with significant infestations, judicious use of insecticides becomes necessary. However, it’s crucial to apply them only when populations exceed the action threshold. Various methods, including sprays, back rubbers, face rubbers, and dust bags, can effectively target the areas where face flies congregate. Ear tag have shown some control as well.
5. Researching Solutions: VetPestX, a valuable resource for selecting suitable insecticides tailored to specific pasture conditions, can aid producers in making informed choices. https://www.veterinaryentomology.org/vetpestx

By employing a combination of these strategies, producers can mitigate the nuisance and potential health hazards posed by face flies, ensuring the well-being of their cattle and the productivity of their operations. In future issues of the blog, I will discuss biological control.

Welcome to Dairy and Livestock Pest News, your premier source for staying ahead of potential pest issues affecting dairy and livestock operations. Here, we offer concise articles and informative videos covering a spectrum of pest-related topics.

Our focus spans the latest research findings and integrated pest management (IPM) strategies tailored to combat flies, ticks, lice, and mites plaguing livestock.

Integrated Pest Management (IPM) stands as a cornerstone approach for effective pest control in dairy and livestock settings. This method employs a diverse range of tactics, including cultural/sanitation practices, mechanical interventions, and biological controls. Chemical insecticides are reserved as a last resort within an IPM program, underscoring our commitment to sustainable pest management practices.

Embarking on an IPM journey involves several key steps. First and foremost, proper identification of the pest is crucial. Subsequent phases encompass routine monitoring and scouting, meticulous sampling, analysis against economic thresholds, strategic implementation of control tactics, and continuous evaluation of efficacy.

Stay informed, stay proactive—welcome to Dairy and Livestock Pest News, your ally in safeguarding animal welfare and agricultural productivity.