Autodissemination of pyriproxyfen as a method for controlling the house fly Musca domestica

House fly (Musca domestica) control is a major challenge in animal agriculture. Here, we tested the feasibility of applying pyriproxyfen (PPF), an insect-growth regulator that controls house flies effectively, using autodissemination methods, in which the flies themselves deliver PPF to their oviposition sites. First, we tried baiting gravid female flies to walk-through stations, where flies would self-treat with PPF and distribute it. This concept worked well in laboratory and indoor cage experiments, but not in the field, as flies appeared reluctant to alight on and collect PPF. Therefore, we tested a different concept of actively coating flies with PPF and then releasing them in different proportions. This concept was tested in laboratory experiments with various manure types in the USA and in Israel. Twenty percent of PPF-coated flies (corresponding to ≥ 2.3 mg/kg PPF) were sufficient to get high control levels (~ 90%) in most of the tested manure types in the US study. Very similar results were obtained in the experiments in Israel but only with poultry manure, whereas low control levels were obtained when cow manure was used. We conclude that autodissemination of PPF using the collect–treat–release “active coating” concept may be practical, depending on manure type, and should be further tested in the field

Potential For Stable Flies And House Flies (Diptera: Muscidae) To Transmit Rift Valley Fever Virus1

Rift Valley fever (RVF), a disease of ruminants and humans, has been responsible for large outbreaks in Africa that have resulted in hundreds of thousands of human infections and major economic disruption due to loss of livestock and to trade restrictions. As indicated by the rapid spread of West Nile viral activity across North America since its discovery in 1999 and the rapid and widespread movement of chikungunya virus from Africa throughout the Indian Ocean Islands to Asia and Europe, an introduced exotic arbovirus can be rapidly and widely established across wide geographical regions. Although RVF virus (RVFV) is normally transmitted by mosquitoes, we wanted to determine the potential for this virus to replicate in 2 of the most globally distributed and common higher flies: house flies, Musca domestica, and stable flies, Stomoxys calcitrans. Neither species supported the replication of RVFV, even after intrathoracic inoculation. However, S. calcitrans was able to mechanically transmit RVFV to susceptible hamsters (Mesocricetus auratus) after probing on infected hamsters with high viral titers. Therefore, S. calcitrans, because of its close association with domestic animals that serve as amplifying hosts of RVFV, should be considered a possible mechanical vector of RVFV, and it may contribute to the rapid spread of a RVF outbreak. Other Stomoxys species present in Africa and elsewhere may also play similar roles

New insights into the genome and transmission of the microsporidian pathogen Nosema muscidifuracis

IntroductionNosema is a diverse genus of unicellular microsporidian parasites of insects and other arthropods. Nosema muscidifuracis infects parasitoid wasp species of Muscidifurax zaraptor and M. raptor (Hymenoptera: Pteromalidae), causing ~50% reduction in longevity and ~90% reduction in fecundity.Methods and ResultsHere, we report the first assembly of the N. muscidifuracis genome (14,397,169 bp in 28 contigs) of high continuity (contig N50 544.3 Kb) and completeness (BUSCO score 97.0%). A total of 2,782 protein-coding genes were annotated, with 66.2% of the genes having two copies and 24.0% of genes having three copies. These duplicated genes are highly similar, with a sequence identity of 99.3%. The complex pattern suggests extensive gene duplications and rearrangements across the genome. We annotated 57 rDNA loci, which are highly GC-rich (37%) in a GC-poor genome (25% genome average). Nosema-specific qPCR primer sets were designed based on 18S rDNA annotation as a diagnostic tool to determine its titer in host samples. We discovered high Nosema titers in Nosema-cured M. raptor and M. zaraptor using heat treatment in 2017 and 2019, suggesting that the remedy did not completely eliminate the Nosema infection. Cytogenetic analyses revealed heavy infections of N. muscidifuracis within the ovaries of M. raptor and M. zaraptor, consistent with the titer determined by qPCR and suggesting a heritable component of infection and per ovum vertical transmission.DiscussionThe parasitoids-Nosema system is laboratory tractable and, therefore, can serve as a model to inform future genome manipulations of Nosema-host system for investigations of Nosemosis

Research and Extension Needs for Integrated Pest Management for Arthropods of Veterinary Importance

In April, 1994, a workshop was held in Lincoln, Nebraska, to update the IPM document that resulted from a similar workshop in Manhattan, Kansas, in 1979 (Anonymous 1979). The workshop was initiated by Dr. Ralph A. Bram, USDA National Program Leader, and organized by Drs. Gustav D. Thomas, USDA-ARS, Lincoln, and John B. Campbell, University of Nebraska, North Platte. Participants were charged with assessing the current status of IPM programs for pests of veterinary importance, identifying needs for program improvements, and recommending future research and extension priorities. Participants, invited from federal and state government research and extension organizations, and the private sector, from the U.S. and Canada, were selected because of their expertise in various sectors of the field of veterinary entomology. IPM needs of eight animal commodity groups were addressed at the Lincoln workshop: 1) poultry; 2) dairy cattle; 3) range beef cattle; 4) confined beef cattle; 5) swine; 6) sheep and goats 7) horses; and 8) dogs and cats. A subcommittee representing each commodity group prepared the chapters contained in the report. Formats vary somewhat from one chapter to another according to the subcommittees\u27 needs, however each chapter contains an overall summary at the beginning, followed by a discussion of the major pests, research and extension needs, and issues pertaining to the animal group. The texts for these chapters were originally prepared in 1995 and updated in 2000-2001. References Anonymous. 1979. Proceedings of a Workshop on Livestock Pest Management: To Assess National Research and Extension Needs for Integrated Pest Management of Insects, Ticks, and Mites Affecting Livestock and Poultry, March 5 7, 1979, Kansas State University, Manhattan, Kansas. USDA, 322pp

House Fly Virus Stops

The house fly is often considered merely a nuisance. But these flies are capable of transmitting animal and human pathogens that can lead to foodborne diseases, including Escherichia coli, Salmonella, and Shigella bacteria. Insecticides are important for control, but house flies are particularly good at developing resistance, and their larvae tend to stay deep enough within their gooey food to avoid exposure to sprays. Scientists at the Agricultural Research Service’s Center for Medical, Agricultural, and Veterinary Entomology (CMAVE) in Gainesville, Florida, are looking at new methods that target adult flies. A promising biological control agent—salivary gland hypertrophy virus (SGHV)—was recently discovered. Once infected with the virus, female flies do not produce eggs, and male flies do not mate. Entomologist Chris Geden in the Mosquito and Fly Research Unit at CMAVE partnered with scientists at the University of Florida (UF) and Aarhus University in Denmark to study the distribution and host range of the virus as well as the effectiveness of different application methods

Host location by \u3ci\u3eSpalangia cameroni\u3c/i\u3e (Hymenoptera: Pteromalidae) in equine associated substrates

House flies, (Musca domestica L.) and stable flies (Stomoxys calcitrans L.) are common pests on equine facilities. Biological control of these flies with pupal parasitoids has become increasingly popular with horse owners but has not been evaluated on equine facilities. Little is known of the substrate preferences of filth fly parasitoids on equine facilities, but the success of release programs may be affected by microhabitat preferences. Spalangia cameroni Perkins was evaluated for location preferences for parasitization of house fly and stable fly puparia in six substrates commonly found on equine farms in Florida. Substrates were evaluated at 20:1 and 5:1 H:P ratios and during the experiment parasitoids had access to all substrates simultaneously. No differences were observed between filth fly host species in any of the measured parameters: total host mortality, parasitoid progeny production and residual host mortality. Significant effects of H:P ratio on host mortality and residual mortality were found but not on progeny production. While there were significantly more hosts killed in the aged shavings than the fresh shavings at the 20:1 ratio, no differences were observed at the 5:1 ratio. Additionally, no differences were found in progeny production across substrates at the 20:1 ratio, but higher reproductive success was observed in several substrates at the 5:1 ratio. These results demonstrate that S. cameroni had substrate preferences but that these preferences were absent with reduced host density. This parasitoid species appears to be effective at parasitizing hosts in the common equine substrates of Florida

Gas Chromatography/Mass Spectrometry Analysis of the Cuticular Hydrocarbons from Parasitic Wasps of the Genus \u3ci\u3eMuscidifurax\u3c/i\u3e

Parasitic Hymenoptera can be difficult to identify by conventional taxonomic techniques. Examination of the cuticular hydrocarbons (CHCs) provides a basis for chemotaxonomic differentiation, which may lead to the discovery of pheromones, and can be a means of examining colonies for species cross-contamination. The parasitic wasps examined were Muscidifurax raptor, M. zaraptor, M. uniraptor, and the gregarious form of M. raptorellus. Species within the genus Muscidifurax, as well as the sex, can clearly be differentiated by examining the gas chromatograms of the CHCs. Identification of the alkanes by mass spectrometry shows uncommon dimethylalkanes and trimethylalkanes for members of the genus. The methyl branched cuticular hydrocarbons of these insects are rare compared to those found on insects reported in the literature, but are present in significant amounts on these insects. Additionally, sexual dimorphism is observed in long chain alkanes (C21–C39) present on male and female cuticular surfaces for these species. Females tend to have cuticular hydrocarbons with methyl branches located externally on the carbon backbone chain for dimethyl-, trimethyl-, and tetramethylalkanes, whereas males tend to have dimethyl- and trimethylalkanes located internally on the hydrocarbon backbone chains. Mass spectra of novel and rare methyl branched compounds identified on these parasitoids are presented