While the housefly (Musca domestica), like other saprophagous, coprophagous, or necrophagous flies, does not directly harm animals or damage structures, it remains a significant pest due to its indirect impacts. One of the most immediate and visible symptoms of a fly infestation is the presence of swarming adults in barns, poultry houses, or stables. These dense flying clouds can disrupt animal behavior and create an uncomfortable and unhygienic environment for both livestock and workers. The constant presence of flies in close proximity to feeding areas, water sources, and rest zones contributes to stress in animals and reduces worker satisfaction and productivity.

More critically, adult houseflies act as mechanical and biological vectors of disease. After breeding in or feeding on manure, decaying organic matter, or carcasses, they can transfer pathogens across long distances onto clean surfaces, animal feed, and living hosts. Musca domestica has been confirmed to carry and transmit over 100 different pathogens. These include viruses such as Newcastle Disease virus, bacteria like Salmonella and E. coli, protozoan parasites such as Giardia, and even the eggs of parasitic worms. This makes houseflies not just a nuisance, but a genuine biosecurity threat to animal health and food safety.

The adult house fly (Musca domestica) is a small but highly adaptable insect, measuring about 6–7 mm in length. It has a yellowish-grey to dark grey body marked by four narrow black stripes on the thorax, clear wings, and large, reddish-brown compound eyes. This species is easily recognized by its rapid flight and presence around decaying organic material. Female house flies typically mate only once in their lifetime, storing sperm to fertilize multiple batches of eggs. When adequate protein sources are available, a single female can lay up to 500 eggs over three to four days, typically in moist, nutrient-rich organic matter such as manure, rotting food, or animal carcasses.

House fly development is strongly influenced by temperature. At optimal conditions between 25–30°C, egg laying, larval development, and pupation proceed quickly. The small, white eggs (around 1.2 mm long) hatch within 24 hours if they remain moist, releasing cream-coloured larvae or maggots. These maggots, 3–9 mm in length, pass through three growth stages (instars) before reaching full size. Once mature, the larvae leave the breeding material to find a dry, sheltered spot to pupate. Pupal cases are oval-shaped and gradually darken from yellow to black as they age. Under warm conditions (above 30°C), adult flies can emerge from the pupal stage in just two days, but development slows significantly at lower temperatures, sometimes taking over three weeks. Adult house flies generally live 15–25 days, though in favourable conditions, their lifespan can extend to two months, allowing for rapid population buildup in uncontrolled environments.

Preventing house fly infestations on farms and in animal housing starts with reducing the conditions that allow them to thrive. Because house flies (Musca domestica) lay their eggs in moist organic matter—such as manure, spilled feed, and decaying waste—the most effective long-term prevention strategy is strict sanitation. Frequent removal of manure, good drainage to eliminate standing water, and careful storage of feed and bedding all help reduce breeding sites. Regular cleaning of equipment, aisles, and corners where organic matter can accumulate is essential to disrupt the fly life cycle.

Monitoring and physical control methods also play a key role in early detection and population suppression. Horiver yellow sticky cards from Koppert can be placed in key fly-attracting areas—near doors, windows, animal pens, and feeding stations—to monitor adult fly activity. These cards not only provide insight into fly population trends but also offer some level of direct control by capturing flies that land on them. For higher fly pressure or large areas such as barns and poultry houses, yellow roller tape is an effective solution. Suspended along walls or ceilings, this adhesive tape captures flying adults on contact, acting as a continuous, passive trapping system.

Used together, sticky cards and roller tape offer both surveillance and suppression benefits, and they’re particularly valuable as part of an integrated pest management (IPM) strategy. These physical tools can be combined with biological and mechanical measures to maintain low fly populations, reduce the need for chemical treatments, and protect both animal health and worker comfort.

Biological control strategies for managing house flies are an essential part of an integrated fly management program, especially in livestock environments. Koppert offers two highly effective biocontrol agents: BioPar and BioFly, each targeting a different stage of the house fly life cycle.

BioPar contains Muscidifurax raptorellus, a parasitic wasp that specifically targets house fly pupae. These wasps are completely harmless to humans and animals. The female wasp searches for fly pupae in the environment and lays an egg inside each one. The developing wasp larva consumes the fly pupa from the inside, preventing it from ever reaching adulthood. Over time, this natural control agent helps suppress fly populations by disrupting their ability to reproduce.

BioFly, on the other hand, introduces Hydrotaea aenescens, a predatory fly species. Also known as the black dump fly, Hydrotaea larvae are voracious predators of house fly larvae. They thrive in moist, organic-rich substrates such as manure and bedding—exactly where house flies prefer to breed. By feeding directly on the maggots of Musca domestica, Hydrotaea aenescens helps reduce the number of larvae that reach the pupal stage.

Used together, BioPar and BioFly offer a one-two punch: BioFly limits the success of early larval development, while BioPar eliminates pupae before they can emerge as adults. When combined with good sanitation, monitoring tools like Horiver sticky cards and yellow roller tape, and physical barriers or trapping, these biological tools form a robust and natural fly control system suitable for long-term use in barns, stables, and poultry houses.