Some of the most common pests within a hog operation include your common house fly and fruit fly. These pests are not only a risk for transferring diseases but are also a nuisance to the animals and people that work or reside in these barns. Once these pests are established within your operation it can be very difficult to control and virtually impossible eliminating these pests. Some of the best methods for control include removal of the breeding environment and chemical intervention. Most people assume that chemical intervention by itself is enough for control of these pests, but without removal of the breeding environment, chemical intervention will be unsuccessful and very frustrating.

To better understand the control methods for flies, it is important to recognize the life cycle for these pests and where we can intervene. The four stages of a fly’s life cycle include the egg, larva or commonly known as a maggot, pupal, and the adult fly. When thinking of your current infestation, note that in general the adult fly only makes up only 20-25% of your infestation and that there is no current intervention against the pupal stage beside eliminating the larva. Current chemical interventions are designed to intervene in the larva and adult fly stages. Whereas when you remove the breeding environment, it helps to control where the eggs are deposited and reduces the ideal media for the development of the larvae.

The breeding environment for these pests usually consists of areas where moisture, feed, and fecal material continually reside. The most common areas include corners, cracks, feeders, and around the farrowing and gestation stalls. Routine cleaning and elimination of this environment helps to reduce the next generation of flies within your operation and therefore better control of these pests.  Crust formation of the pits is also a main area of concern. Agitation during the pit pumping process and/or pit additives will help break apart the crust to reduce the breeding environment.

As mentioned earlier for chemical intervention, they are designed to affect the larvae and adult flies. The four common types of interventions used are larvacides, adult fly baits, adult fly sprays, and barn sprays. Larvacides are used in areas where the breeding environment is present or normally resides. As its name indicates, larvacides eliminate the larvae and therefore only affect this stage of the fly’s life cycle. All the other three types of chemical intervention work to affect the adult fly population.

Adult fly baits are to be used in areas where flies congregate and the animals are unable to ingest these products. A good example of this would be on window sills. As for adult fly sprays, they are to be applied using a fogger or mister to project throughout the entire barn. This will be the most impactful method of eliminating the adult flies. Last are barn sprays and these have a residual effect once they are sprayed onto the walls can last up to a month or more. Barn sprays are to be done when animals are unable to come in contact with this spray when applying and it is allowed to dry.

When applying any chemical intervention safety should be of a high concern to the animals, as well as the person applying these products. Gloves, coveralls, eye protection, and masks should be considered during the application process but may vary on the type of intervention that you are applying. Also, please read and follow the instructions on the products you use to ensure the safety of the animal.  It is also important to note that some of the products that you use do have a slaughter withdrawal period and to make sure you are abiding to those standards as well.

For any questions or concerns regarding this topic please do not hesitate to contact our Pipestone team of veterinarians and swine specialist at 507-562-PIGS.

Scott VanderPoel, DVM

Pipestone Veterinary Service

scott.vanderpoel@pipestone.com