Publications by authors named "Alec C Gerry"

Article Synopsis
  • The study examines how the sex and age of adult Culex tarsalis mosquitoes affect their survival when exposed to permethrin, a common insecticide.
  • Results showed that younger and older females responded differently to permethrin, with older females having higher mortality rates after initial exposure, while males had slightly higher mortality than females in the first few minutes.
  • Ultimately, all mosquitoes tested died within 30 minutes, indicating that they are susceptible to permethrin, which is important for understanding insecticide resistance in mosquitoes.
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Sex chromosomes often differ between closely related species and can even be polymorphic within populations. Species with multifactorial sex determination segregate for multiple different sex determining loci within populations, making them uniquely informative of the selection pressures that drive the evolution of sex chromosomes. The house fly (Musca domestica) is a model species for studying multifactorial sex determination because male determining genes have been identified on all six of the chromosomes, which means that any chromosome can be a "proto-Y".

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Article Synopsis
  • The chicken body louse is a parasite that feeds on feathers and negatively affects the health and productivity of egg-laying chickens, especially in cage-free settings.
  • A study was conducted comparing infested flocks to uninfested controls, measuring behaviors and welfare indicators like pecking, preening, and presence of skin lesions.
  • Results showed infested chickens engaged in more preening and had skin lesions, highlighting the need for more research on the economic impact of chicken body lice on welfare and productivity.
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Background: As a primary vector of bluetongue virus (BTV) in the US, seasonal abundance and diel flight activity of Culicoides sonorensis has been documented, but few studies have examined how time of host-seeking activity is impacted by environmental factors. This knowledge is essential for interpreting surveillance data and modeling pathogen transmission risk.

Methods: The diel host-seeking activity of C.

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The house fly, L., is a significant human and livestock pest. Experiments used female adult house flies glued onto toothpicks for controlled exposure of their tarsi alone (tarsal assay) or their tarsi and proboscis (proboscis assay) with a sucrose solution containing imidacloprid at either a low (10 µg/mL) or high (4000 µg/mL) concentration.

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In the western United States, Culex tarsalis is the most important vector of West Nile virus. Insecticides containing permethrin or other pyrethroid compounds are commonly used to control these mosquitoes. Because of the range of environments where Cx.

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Background: The house fly (Musca domestica L.) is a synanthropic fly species commonly associated with confined animal facilities. House fly control relies heavily on insecticide use.

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Most population genetic studies concern spatial genetic differentiation, but far fewer aim at analyzing the temporal genetic changes that occur within populations. Vector species, including mosquitoes and biting midges, are often characterized by oscillating adult population densities, which may affect their dispersal, selection, and genetic diversity over time. Here, we used a population of Culicoides sonorensis from a single site in California to investigate short-term (intra-annual) and long-term (inter-annual) temporal variation in genetic diversity over a 3 yr period.

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In southern California, USA, annual reoccurrence of bluetongue infection in cattle (Bos taurus Linnaeus (Artiodactyla: Bovidae)) suggests that bluetongue virus (BTV) persists year-round but escapes detection during cooler months, reappearing when the weather gets warmer. The persistence of the virus in the adult biting midge vector, Culicoides sonorensis Wirth and Jones (Diptera: Ceratopogonidae), has been suggested. However, it is unknown whether adult C.

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Culicoides Latreille (Diptera: Ceratopogonidae) biting midges are hematophagous flies that can transmit several disease-causing pathogens to animals. Surveillance of Culicoides is important for understanding pathogen transmission risk. The most commonly used traps for midge surveillance are suction traps baited with UV light or CO2.

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Culicoides Latreille (Diptera: Ceratopogonidae) biting midges are vectors of important animal pathogens including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). While some Culicoides species present in the southern California desert are implicated in the transmission of these viruses to ruminant animals, these species have not been extensively studied due in part to the challenge of identifying Culicoides to species and to the lack of published gene sequences for these species to support their molecular identification. In this study, Culicoides were captured using suction traps baited with either carbon dioxide or UV light from transitional habitat between the southern California peninsular mountain ranges and the Colorado desert of southeastern California.

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Stable flies (Stomoxys calcitrans) are blood-sucking insects commonly associated with cattle production systems worldwide and are known to cause severe irritation to cattle due to painful bites. Cattle react to biting stable flies with an aggregating behavior known as bunching. Bunching behavior reduces grazing or feed consumption and thus reduces cattle productivity and welfare.

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Insecticide resistance in pest populations is an increasing problem in both urban and rural settings due to over-application of insecticides and lack of rotation among insecticidal chemical classes. The house fly (Musca domestica L.) is a cosmopolitan pest fly species implicated in the transmission of numerous pathogens.

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Monitoring house fly (Diptera: Muscidae) activity on animal facilities is a necessary component of an integrated pest management (IPM) program to reduce the negative impacts of these flies. This article describes monitoring methods appropriate for use on animal facilities with discussion of monitoring device use and placement. Action thresholds are presented where these have been suggested by researchers.

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The house fly is a ubiquitous pest commonly associated with animal facilities and urban waste. When present in large numbers, house flies can negatively impact humans and animals through nuisance and the transmission of pathogens. Since the development of fly traps and sticky papers to capture flies in the late 1800s, these and other methods have been used as a means to monitor change in house fly density or fly activity over time.

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House flies ( L.) are common synanthropic pests associated with confined animal operations, including dairy farms. House flies can cause substantial nuisance and may transmit human and animal pathogens.

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Insecticide resistance in pest populations is an increasing problem in both urban and rural settings caused by over-application of insecticides and lack of rotation among chemical classes. The house fly (Musca domestica L.) is a cosmopolitan fly species implicated in the transmission of numerous pathogens, and which can be extremely pestiferous when present in high numbers.

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The northern fowl mite, Ornithonyssus sylviarum, is one of the most common and damaging ectoparasites of poultry. As an obligate blood feeding mite, the northern fowl mite can cause anaemia, slower growth, and decreased egg production of parasitized birds. However, the impact of mites or other ectoparasites on hen behaviour or welfare is not well studied.

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House flies (Musca domestica L.) are mechanical vectors of food-borne pathogens including Salmonella spp., Escherichia coli O157:H7, and Shigella spp.

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Bunching is the term used to describe the protective aggregating behavior of cattle against the painful bites of stable flies (Stomoxys calcitrans), where cattle gather in a group with their heads to the center of the group and their tails to the outside to reduce stable fly attack. Both sexes of the stable fly feed on blood, and their painful bites negatively impact cattle health, productivity and welfare. A longitudinal study was conducted from April to July 2017 to estimate the stable fly activity on 20 California dairies (average herd size = 2466 ± 1050), to determine stable fly activity that induced bunching, and to evaluate the association between management and environmental factors, and cattle bunching.

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Background: Stable isotope labeling is a promising method for use in insect mark-capture and dispersal studies. Culicoides biting midges, which transmit several important animal pathogens, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), are small flies that develop in various semi-aquatic habitats. Previous Culicoides dispersal studies have suffered from the limitations of other labeling techniques, and an inability to definitively connect collected adult midges to specific immature development sites.

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The mortality rate of a field population of house fly (Musca domestica L.) was determined for a granular fly bait containing the active ingredient indoxacarb, which was compared to two commercially available granular fly baits containing either dinotefuran or cyantraniliprole. Indoxacarb was applied at three different application rates 0.

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Haematobia irritans (L.) (Diptera: Muscidae) were netted from pastured cattle in California over two summers, with the goal of documenting on-host sex ratios and mating success as they might vary with repellent applications. Sex ratios were calculated from 100 adults per herd per date, and mating status of females (n = 30 per herd per date) was assessed by dissection of spermathecae.

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