- Animals: bovine, swine
- Animal Products: dairy
- Pest Management: biological control
Pupal parasitoids are often used as sustainable biological control options for filth fly pests on livestock operations. Filth flies, such as stable flies (Stomoxys calcitrans) and house flies (Musca domestica), are mechanical vectors of disease and can cause pain and losses of condition to livestock. Conventional control of these pests has relied on high doses of various insecticides. Filth fly pests are becoming increasingly resistant to many licensed insecticides and the increase of chemical use is harmful to the environment. The purpose of this project is to improve the use of pupal parasitoids of filth flies as part of a sustainable biological control program on livestock operations. Though used often, there is only limited empirical information on the microhabitat preferences and protocols for release of Spalangia cameroni Perkins (Hymenoptera: Pteromalidae) that will assure their effectiveness. The goal of this research was to (1) define the odor cues which influence host location by Spalangia cameroni, (2) assess dispersal to host sites from release locations in the field, and (3) outreach and extension activities to increase the operator awareness of biological control of filth flies. Impacts of this research include increasing the effectiveness of the parasitoids, reducing exposure of humans and animals to toxic insecticides, managing insecticide resistance by improving sustainable biological control options and ultimately reducing cost and increasing the use of these parasitoids to manage filth flies.
The purpose of this project was to improve the use of pupal parasitoids of filth flies, such as house flies and stable flies, as part of a sustainable biological control program on livestock operations. These parasitoids in the family Pteromalidae are often used as non-chemical alternatives to chemical insecticides. Several species, including Spalangia cameroni Perkins, are commercially available and sold widely. However, there is only limited empirical information on the microhabitat preferences and protocols for release that will assure their effectiveness. The olfactory cues of host location by these wasps has been given little attention. As a consequence of this insufficient knowledge, these parasitoids have not achieved widespread success. Improvement of use is contingent upon understanding the factors influencing host location and dispersal. The proposed project will determine preferences for odor cues which influence host location as well as parasitism differences determined by dispersal range.
Biological control is an important and sustainable option for livestock operators to control their filth fly pests. Filth flies must be minimized in livestock operations primarily because they can transmit more than 100 pathogens that cause disease in humans and animals (Malik et al. 2007). Losses of physical condition have also been observed in livestock pressured by flies (Todd 1964). Field surveys of stable and house flies have revealed high levels of resistance to most commercially available insecticides due to overuse. This research will reduce the risk of transmitting diseases to humans and livestock and reduce chemicals in the environment by minimizing the size of filth fly populations using natural methods. Livestock operations will be safer and more profitable.
Increasing the knowledge of the dispersal and detection of host location by Spalangia cameroni has provide insight in to the post-emergence cues used by parasitoid females to locate hosts in microhabitats. With this understanding of host location and further identification of the volatile chemicals associated with attraction, livestock operators will be able to place parasitoids for release where they will be able to locate hosts, maximizing parasitoid effectiveness.
Project objectives:div style="margin-left:1em;">
The goals of this research were to (1) define the odor cues which influence host location by Spalangia cameroni, (2) assess dispersal to hosts sites from release locations in the field, and (3) increase the operator awareness of biological control of filth flies.
Goal (1): Define the odor cues which influence host location by Spalangia cameroni
Objective 1: To assess the attraction of S. cameroni to the larvae of house flies at different concentrations.
Objective 2: To assess the attraction of S. cameroni to manures of three different farm animals and the attraction to the interaction between developing larvae in the manure.
Goal (2): Assessment of dispersal to hosts sites from release locations in the field
Objective 3: To assess dispersal range of S. cameroni when hosts are immediately present at many distances and when hosts are not immediately available.
Goal (3): Outreach and extension activities to increase the operator awareness of biological control of filth flies.
Objective 4: Development of an extension publication to assist farmers in the use and selection of parasitic wasps for filth fly control.