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At least 973 records · Page 54Linked to original sources
PubMed2005

Vegetation-derived cues for the selection of oviposition substrates by Anopheles albimanus under laboratory conditions.

Oviposition response of gravid Anopheles albimanus Wiedemman (Diptera: Culicidae) females to water containing Brachiaria mutica, Cynodon dactylon, Jouvea straminea, Fimbristylis spadicea, and Ceratophyllum demersum was investigated. Gravid An. albimanus females deposited similar egg numbers in cups containing natural plants in water from natural breeding sites and in cups containing natural plants in distilled water. Gravid mosquitoes deposited significantly more eggs in cups containing natural plants in water from natural breeding sites than in cups containing artificial plants in water from the corresponding natural breeding sites. These results were confirmed in experiments conducted in a wind tunnel, indicating that female response is mediated by chemical cues from plants. Bioassays with organic extracts of all 5 plant species indicated that these extracts at 100%, 10%, and 1% concentrations had an oviposition repellent effect, while attractiveness was observed at 0.1%, 0.01%, and 0.001%. Gas chromatography and mass spectrometry analysis of the organic extracts found in all 5 plants showed a mixture of terpenoid and alcohol compounds, among them: guaiacol, phenol, isoeugenol, longifolene, caryophyllene, phenyl ethyl alcohol, and p-cresol. These results suggest that middle-range volatiles from plants may function as chemical cues for the female's oviposition response in this mosquito species.

Animals↗
PubMed1995

Repellent action of neem cream against mosquitoes.

Neem cream was used as mosquito repellent to provide protection against Aedes albopictus, Ae. aegypti, Culex quinquefasciatus, Anopheles culicifacies and An. subpictus mosquitoes. The application of neem cream on exposed body parts @2.0 gm/person showed 78 (range 65-95), 89 (range 66-100) and 94.4 (range 66-100) per cent protection against Aedes, Culex and Anopheles mosquitoes respectively. Significant difference was observed between neem cream treated and untreated group of population for Aedes mosquitoes (p < 0.001). Application of neem cream was found to be a safe and suitable alternative to insecticide impregnated coils for personal protection against mosquitoes and one application was 68% effective for four hours.

Animals↗
PubMed1983

Failure of brewer's yeast as a repellent to fleas on dogs.

Active and inactive brewer's yeast, when given as a dietary supplement to dogs at the rate of 14 g/day, failed to repel or kill fleas. Twenty dogs in each of 3 groups were inoculated weekly for 7 weeks with 100 unfed cat fleas (Ctenocephalides felis). One group served as a control while one group received inactive and the other active yeast during the last 5 weeks of the trial. There were no significant differences in flea counts among the 3 groups during the first 4 weeks of yeast supplemental feedings. Total flea counts during the 5th week of yeast supplementation did not differ significantly from the counts on control dogs, although there was a significant difference between counts from dogs receiving active and those receiving inactive yeast.

Animals↗
PubMed2000

Integration of repellents, attractants, and insecticides in a "push-pull" strategy for managing German cockroach (Dictyoptera: Blattellidae) populations.

"Push-pull" is a behavior manipulation strategy in which behavior-modifying stimuli are integrated with a pest control agent. We evaluated the efficacy of an insecticide bait in combination with attractants ("pull"), repellents ("push"), or both ("push-pull") using a hydramethylnon-based bait, feces-contaminated surfaces as an attractant, and methyl neodecanamide-treated surfaces to repel cockroaches. Both adult males and first-instar German cockroaches, Blattella germanica (L.), chose shelters nearest the attractant-treated surfaces and farthest from the repellent-treated surfaces. Food consumption was highest from food nearest the preferred shelters, and mortality was highest when the insecticide bait was near the preferred shelter. These patterns were more apparent in first instars than in adults. Our results from large arena studies in the laboratory show that the push-pull strategy can be used to displace pests from resources or commodities that are to be protected, and simultaneously lure the pest to an attractant source coupled with a pest control agent. Concentrating cockroaches into a limited area should facilitate the precision-targeting of the pest population and promises to reduce insecticide use.

Animals↗
PubMed1981

[The effect of blood-sucking diptera on the weight of grazing heifers].

It was demonstrated experimentally that bloodsucking dipterans (gad-flies, gnats, midges, black flies) influenced negatively weight increments of grazing heifers and that it was suitable to treat the heifers with repellents; 10% water emulsion of the repellent diethyltoluamide was used for heifer spraying in the intervals of 48 hours. Over the 66 days of the experiment, the total live weight of one heifer from the test group increased by 5.00 kg, in comparison with the controls. The coefficient of loss per untreated animal was 105.00 Kcs., the returns of investments per 1.00 Kcs of investment costs were 1.90 Kcs. Owing to worse climatic conditions in the experimental years which significantly differed from meteorological conditions in the previous four years, which ensued from mathematico-statistical evaluation, differences in weight increments over the period of study were statistically insignificant.

Animals↗
PubMed1987

Toxic effects of mosquito coil (a mosquito repellent) smoke on rats. II. Morphological changes of the respiratory system.

A group of 20 female albino rats was exposed to mosquito coil smoke, 8 h a day, 6 days per week, for 60 days. An additional group receiving air exposure served as control. The smoke-exposed animals had a lower body weight than the controls. Smoke-induced histopathological lesions, including an inflammation of the tracheal epithelium, atelectasis of the lung parenchyma, emphysema, increase of alveolar macrophages in the alveolar space and perivascular infiltration of polymorphonuclear cells were observed in the experimental rats. An elevation of enzyme activities of lactate dehydrogenase, glutamate pyruvate transaminase, glutamate oxoacetate transaminase and acid phosphatase were found in the serum of the smoke-exposed rats indicating the enzymes were released from the damaged tissues into the blood stream.

Animals↗
PubMed2005

Anointing chemicals and ectoparasites: effects of benzoquinones from millipedes on the lone star tick, Amblyomma americanum.

Many mammals and birds roll on or rub themselves with millipedes that discharge benzoquinones. Chemicals transferred from millipedes onto the integument of anointing animals are thought to deter ectoparasites. We tested the lone star tick, Amblyomma americanum (L.), for responses to three widespread components of millipede defensive secretions, 1,4-benzoquinone; 2-methyl-1,4-benzoquinone (toluquinone); and 2-methoxy-3-methyl-1,4-benzoquinone (MMB). In toxicity tests, ticks were confined for 1 hr in filter-paper packets treated with serial dilutions of each of the benzoquinones or the commercial acaricide permethrin. Ticks were least affected by toluquinone, and most affected by permethrin. Of the benzoquinones, only MMB showed repellent activity. Behavioral assays were more sensitive than mortality for measuring the effects of the benzoquinones. Latencies for ticks to right themselves and to climb were greater with all compounds, even at the lowest concentrations, than with controls. Ticks exposed to low concentrations of benzoquinones appeared to recover over time, whereas those exposed to high concentrations exhibited behavioral abnormalities 1-3 mo later. Our results indicate that benzoquinones appropriated via anointing may reduce the tick loads of free-ranging animals, although key questions remain on the amounts of these compounds available to and effectively appropriated by anointing animals.

Animals↗
PubMed2004

[Historical study of a moth repellent "Fujisawa Camphor" (4) - newspaper advertisements for "Fujisawa Camphor" in the Meiji Era].

Newspaper advertisements were frequently available as one way of communicating news about new products to the general public during the middle of the Meiji Era. The first newspaper advertisement of "Fujisawa Camphor"' appeared in the Osaka Asahi on June 1, 1989. At that time, the newspaper advertisements of OTC were brilliant and the space taken by them was large, in some cases covering a full page. They appeared daily. However, the ad for Fujisawa Camphors was small and simple. The appeal points of the Fujisawa Camphor advertisement were as follows: 1. Fujisawa Camphor, crystals of refined camphor, are hard and colorless.2. It is effective for insecticide and prevents moisture.3. It is widely used by governments and the military.4. It removes bad smell to protect against infectious diseases.

Advertising↗
PubMed2004

[Historical study of the moth repellent, "Fujisawa Camphor" (5) - quality assurance and consumers].

In the Meiji Era, the concepts of consumers did not exist; however, customers were certainly valued at that time based on the policy that "the customer is always right". Customers were always considered as guests, and there were no conflicting matters with manufacturers. The sales agency for Fujisawa camphor, Fujisawa Company, took up a positive attitude towards customer services. First, the company excluded imitation products in order to protect customers from poor quality, and second, the company released data regarding camphor comparisons and effects with other insecticides. At that time, they seemed to fear being talked about in terms of the mistaken use of camphor. The company commissioned a public research laboratory to study the interaction of camphor and precious metals, and made an appeal to customers for the truth.

Animals↗
PubMed2005

Repellent and insecticidal activities of essential oils from Artemisia princeps and Cinnamomum camphora and their effect on seed germination of wheat and broad bean.

Repellent and insecticidal activities of essential oils extracted from leaves of Artemisia princeps Pamp and seeds of Cinnamomum camphora (L.) Presl. against storage pests Sitophillus oryzae L. and Bruchus rugimanus Bohem were investigated. Results showed that the two individual oils displayed good, but their mixture (1:1) exhibited much better repellent activities at concentrations from 250 to 1000 microg g(-1) and insecticidal actions at concentrations 1000 microg g(-1) against the test beetles S. oryzae and B. rugimanus. Oils from A. princeps and C. camphora applied individually were significantly toxic to seed germination of wheat at 500 microg ml(-1). However, no toxic effects were found when the two oils were mixed (1:1 w/w) at the same concentration. These observations indicated that the mixture of the two plant-derived oils had a synergic effect and could be used in the control of storage pests.

Animals↗
PubMed1990

Evaluating sources of indoor air pollution.

Evaluation of indoor air pollution problems requires an understanding of the relationship between sources, air movement, and outdoor air exchange. Research is underway to investigate these relationships. A three-phase program is being implemented: 1) Environmental chambers are used to provide source emission factors for specific indoor pollutants; 2) An IAQ (Indoor Air Quality) model has been developed to calculate indoor pollutant concentrations based on chamber emissions data and the air exchange and air movement within the indoor environment; and 3) An IAQ test house is used to conduct experiments to evaluate the model results. Examples are provided to show how this coordinated approach can be used to evaluate specific sources of indoor air pollution. Two sources are examined: 1) para-dichlorobenzene emissions from solid moth repellant; and 2) particle emissions from unvented kerosene heaters. The evaluation process for both sources followed the three-phase approach discussed above. Para-dichlorobenzene emission factors were determined by small chamber testing at EPA's Air and Energy Engineering Research Laboratory. Particle emission factors for the kerosene heaters were developed in large chambers at the J. B. Pierce Foundation Laboratory. Both sources were subsequently evaluated in EPA's IAQ test house. The IAQ model predictions showed good agreement with the test house measurements when appropriate values were provided for source emissions, outside air exchange, in-house air movement, and deposition on "sink" surfaces.

Air Pollution↗
PubMed2005

Combination of a non-pyrethroid insecticide and a repellent: a new approach for controlling knockdown-resistant mosquitoes.

Although pyrethroid-treated materials are a promising tool for the prevention and the control of dengue in the tropics, the development of pyrethroid resistance in the main mosquito vector (Aedes aegypti) may negate their use for personal and/or community protection. In that context, the efficacy of a mixture of a repellent (N,N-diethyl toluamide [DEET]) and a non-pyrethroid insecticide (propoxur) was investigated under laboratory conditions against both pyrethroid-susceptible and pyrethroid-resistant mosquitoes with the knockdown resistance (kdr) mutation. The results showed that a combination of propoxur and DEET induced a knockdown effect and mortality as high as deltamethrin (a standard pyrethroid) against the susceptible strain, and significantly higher efficacy against the pyrethroid-resistant strain. This could be explained mainly by the existence of a strong synergistic interaction between DEET and propoxur in mosquitoes. This study constitutes a first step towards an alternative strategy for improving mosquito control in areas with pyrethroid resistance.

Animals↗
PubMed1982

In vitro skin evaporation and penetration characteristics of mosquito repellents.

An in vitro apparatus was used to study mosquito repellent evaporation and penetration characteristics with skin. The mosquito repellents 2-ethyl-1,3-hexanediol, N,N-diethyl-m-toluamide, N,N-diethyl-p-toluamide, 1-(butylsulfonyl)hexahydro-1H-azepine, and N,N'-dicyclohexamethyleneurea were studied. In vitro repellent duration, calculated from repellent evaporation rates, was compared to in vivo duration at the same dose (0.3 mg/cm2) to assess the validity of the model. In vitro durations for 2-ethyl-1,3-hexanediol, N,N-diethyl-m-toluamide, N,N-diethyl-p-toluamide, and N,N'-dicyclohexamethyleneurea correlated with in vivo durations (r2 = 0.94), although in vitro durations was longer than in vivo duration. 1-(Butylsulfonyl)hexahydro-1H-azepine, which had the longest in vivo duration, had an in vitro duration that exceeded the test period (12 hr). The 0-12-hr in vitro percutaneous penetration correlated with corresponding data available from in vivo studies.

Aedes↗
PubMed2005

Field evaluation of spatial repellency of metofluthrin impregnated plastic strips against mosquitoes in Hai Phong City, Vietnam.

Spatial repellency of metofluthrin-impregnated polyethylene plastic strips against mosquitoes, Aedes aegypti and Culex quinquefasciatus, were studied in a residential area in Hai Phong city, Vietnam. Thirty houses were selected as trial sites; half of these were assigned as untreated control and the other half were assigned for treatment. Primarily, irrespective of the room size, one room was treated with one strip. The dominant species in the trial sites were Culex quinquefasciatus and Aedes aegypti. A rapid decrease in the mosquito index was observed immediately after the treatment with metofluthrin strips, and treatment was effective for at least 6 weeks.

Animals↗
PubMed2006

In vitro permeation of repellent DEET and sunscreen oxybenzone across three artificial membranes.

DEET and oxybenzone are two essential active ingredients in repellent and sunscreen products. We performed a series of in vitro diffusion studies to evaluate the transmembrane permeation of DEET and oxybenzone across three artificial membranes, low-density polyethylene (LDPE), low fouling composite (LFC) and mixed cellulose esters (MCE), from concurrent use of commercial repellent and sunscreen preparations. Permeation of DEET and oxybenzone across the test membranes was synergistically increased when both the repellent and the sunscreen formulations were applied simultaneously. Different application sequences and formulation types also resulted in variable permeation profiles of DEET and oxybenzone. Compared to biological piglet epidermis under the identical experimental conditions, transmembrane permeation of DEET was suppressed in LDPE and LFC membranes, but enhanced in MCE membrane; transmembrane permeation of oxybenzone was reduced in LFC membrane, but increased in LDPE and MCE membranes. Permeability coefficients of DEET and oxybenzone in all three artificial membranes were significantly different from those in piglet skin. It was concluded that the permeation profiles of the compounds were dependent upon physicochemical characteristics of the membranes and the formulations.

Animals↗
PubMed2001

Repellent and toxic effects of plant extracts on subterranean termites (Isoptera: Rhinotermitidae).

The effects of four plant extract formulations on the orientation and survival of subterranean termites were tested. In choice experiments, extract-treated filter paper had a significantly repellent effect on groups of Reticulitermes santonensis De Feytaud, R. virginicus (Banks), Coptotermes formosanus Shiraki, and Schedorhinotermes intermedius Breinli. There was no species-specific difference in avoidance behavior toward the tested concentrations. No-choice experiments revealed toxic properties of all investigated extracts by contact or airborne compounds against R. santonensis. However, high termite mortality was only achieved by forced direct or forced indirect exposure to the plant material, Feeding deterrence or digestive toxicity could not be judged in these experiments. One of the extracts was efficiently used for soil treatments to protect a food substrate against R. santonenis infestation. Extract-treated barriers in the experiments did not affect mortality compared with control trials but prevented termites from penetrating treated soil.

Animals↗
PubMed2000

A blinded, controlled trial of an ultrasound device as mosquito repellent.

Ultrasound emitting devices are used to repel mosquitoes. We tested the repelling properties of a commercially available ultrasound device in a domestic setting in Gabon. Devices emitting three different block frequencies ranging from 3 to 11 kHz were tested in a paired, cross-over blinded and placebo controlled trial during eighteen nights in nine pairs of houses. A total of 7485 mosquitoes (10% Anopheles, 62% Culex, 27% Mansonia and 1% Aedes) were caught, 23 per house per night. There was no significant difference in landing rate between the houses with ultrasound device and the houses with placebo for any species of mosquito. Thus the ultrasound device used was not effective against mosquitoes in this strictly controlled trial.

Animals↗
PubMed2004

Toxicity and behavioral effects of nootkatone, 1,10-dihydronootkatone, and tetrahydronootkatone to the formosan subterranean termite (Isoptera: Rhinotermitidae).

Toxicity and behavioral effects of nootkatone and two of its derivatives, 1,10-dihydronootkatone and tetrahydronootkatone, to Coptotermes formosanus Shiraki were investigated on workers from two different colonies by using topical application assays, repellency assays, and sand barrier assays. The acute toxicity of the nootkatones on workers from both colonies increased as the saturation of the molecule increased, but the difference was significant for only one colony. The results of the repellency assays showed a similar trend of efficiency; the threshold concentration for significant repellency was four-fold higher in nootkatone treatments (50 ppm) than in the reduced derivatives 1,10-dihydronootkatone or tetrahydronootkatone (12.5 ppm). In sand barrier assays, a concentration of 100 ppm of any of the three chemicals significantly reduced termite survival, tunnel building, and food consumption after a 12-d exposure. Termites preexposed to 100 ppm nootkatone-treated sand and placed in containers without nootkatone for 15 d continued to exhibit abnormal feeding and digging behaviors; survivorship, tunneling, and feeding activities were significantly reduced by 83.5, 63.2, and 95.4%, respectively. Termites pretreated for 12 d at concentrations of 50 and 75 ppm nootkatone and tetrahydronootkatone returned to normal digging activity after they were removed from the treatments, but their feeding activity was significantly reduced.

Animals↗