Search

Arthropod ectoparasites are the most ubiquitous life forms affecting ruminant animals and commonly affect the daily activity and health status of ruminants. This article describes the phenology of several important ectoparasites of livestock and small ruminants, and delineates some general control and management strategies for protecting domestic ruminants.

Parasites are a common cause of dermatological disease in the dog and cat. Knowledge of different miticidal options for the common parasitic diseases is imperative when choosing the appropriate treatment for a patient. This is especially important with the recent advent of safer and more effective antiparasitic medications. Diagnostic and therapeutic methods for Cheyletiella spp., Demodex spp., Notoedres cati, Sarcoptes scabei, and Otodectes cyanotis are discussed, with emphasis on protocols for miticidal therapies, as well as safety concerns and side effects. This information will allow the practitioner to choose the safest and most efficient treatment for parasitic skin disease in their small animal patients.

An indigenous strain (IHEM 18747) of Beauveria bassiana (Balsamo) Vuillemin (Deuteromycetes) was evaluated for its in vitro entomopathogenic activity against the parasitic mite Psoroptes ovis Hering (Acari: Psoroptidae) from rabbits. The following aspects were evaluated: (1) effects of conidial concentration on the viability of adult females; (2) influence of the infection on the fertility, and on the hatchability of eggs; (3) and transmission of infection between mites, and from contaminated surface. Adult females immersed into increasing concentrations of conidia (10(4)-10(9)conidia ml(-1)) showed a dose-related susceptibility. At the highest concentration of conidia, LT50 was 1.6 days while LT50 of the controls reached 5.8 days. The fungus was able to sporulate on the body surface and 100% of the mites were covered with mycelium after immersion in solutions containing 10(7)-10(9)conidia ml(-1). One hundred percent of healthy mites exposed to infected cadavers or surfaces acquired the infection (LT50 reached 1.9 and 1.73 days, respectively, versus 6.1 and 5.1 days in controls, respectively). Egg laying was not reduced by the fungal infection but both the hatchability of the eggs and the life span of the emerging larvae were significantly reduced. Eggs directly infected with the fungus did not show reduced hatchability but the life span of the larvae was shortened. It is concluded that B. bassiana has a high entomopathogenic activity against Psoroptes spp. The in vivo use of this biocontrol agent against Psoroptes spp. in rabbit, sheep and cattle deserves further attention.

Despite the potential benefits offered by vaccination against ectoparasites, there have been few commercial successes with this strategy, in spite of sustained efforts using increasingly sophisticated techniques. This review outlines the progress and challenges offered by recent research into vaccination against some of the major ectoparasites of veterinary importance, and provides an insight into the opportunities arising from our increased understanding of the immunology of host-parasite relationships and the potential for exploitation of this knowledge and that arising from new genomic data provided by expressed sequence tag projects.

Background: Itching is a characteristic symptom in various forms of dermatosis, especially atopic dermatitis; consequently it is a major diagnostic criterion. All features are similar to events seen in patients, hence NC/Nga mice are considered to be a suitable model of human atopic dermatitis. However, there were data spreads in commencing time and the degree of skin lesions in NC/Nga mice., Objectives: In the present study, we attempted to improve experimental conditions to induce stable skin lesions and to establish a more appropriate method. Methods NC/Nga mice were kept together with skin-lesioned mice during the experiment period (mixed-NC mice). The dermatitis scores of face, ears and rostral back were assessed. Scratching behaviour was measured using an apparatus, MicroAct (Neuroscience, Tokyo, Japan). Transepidermal water loss (TEWL) and serum total IgE levels were also measured. To observe the presence of mites, the skin of the rostral backs of the mixed-NC mice was stripped using cellulose tape. We also investigated the effects of fipronil (Wako, Osaka, Japan), an acaricidal compound, on skin lesions and scratching behaviour of these mixed-NC mice., Results: In mixed-NC mice, skin lesions appeared from 2 weeks, worsened gradually and reached peak levels of a dermatitis score in 8 weeks. Scratching behaviour increased significantly from day 3. TEWL also increased from day 3, but total IgE increased from day 7. Mites were observed on the rostral backs of mixed-NC mice from day 3, and all mice had these mites on day 28. Giving pretreatment with fipronil (Wako), the skin lesions and scratching behaviour of mixed-NC mice was significantly suppressed., Conclusions: The findings of the present study suggest that the method of being kept together with skin-lesioned mice can induce stable skin lesions and scratching behaviour at an early stage, without skin lesions. This method could help investigate a more stable evaluation of the effects on symptoms of atopic dermatitis, and mechanisms of the itching. It was considered that parasitism of mites, not allergic reactions, was the pathogenesis of skin lesions and scratching behaviour in mixed-NC mice.

These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of acaricides against mange and itch mites on ruminants. Information is provided on the selection of animals, dose determination, dose confirmation and field studies, record keeping and result interpretation. These guidelines also are intended to assist the investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures.

Residual populations of storage mites sheltering in crevices and cracks escape conventional control treatments and are implicated in the infestation of newly harvested grain. In a series of 24 h laboratory tests, the performance of solitary adults of two predatory mite species, Cheyletus eruditus (Schrank) and Blattisocius tarsalis (Berlese), were assessed for controlling small numbers of the flour mite Acarus siro (L.). Tests were carried out in the presence or absence of prey refuges or grain debris to afford shelter to the flour mites. While C. eruditus had a significant effect on the motile stages of A. siro, in contrast B. tarsalis had a significant effect on the eggs. The maximum percentage of motile stages of A. siro eaten by C. eruditus was 82%, whereas the minimum percentage of A. siro eggs eaten by B. tarsalis was 99%. While the performance of C. eruditus in predating on motile stages of the flour mite was hindered by the presence of the prey refuge (38% eaten) and grain debris (25% eaten), the performance of B. tarsalis in predating on flour mite eggs was unaffected (100% eaten in presence of prey refuge or grain debris). In prolonged exposures (36 days) the performance of 2, 4 or 8 adult predators, either a single species or a combination of both, was assessed for their ability to control a population of the flour mite developing up to F(2) from an initial inoculum of 80 females and 20 males, allowed to oviposit for 72 h in the absence of predatory mites. The maximum reduction in prey population of 80% was achieved with eight B. tarsalis. Combining the two predatory species did not enhance the reduction of A. siro population.

The biology of Kampimodromus aberrans (Oudemans), a predator of the big bud mite, Phytoptus avellanae Nalepa, was studied under laboratory conditions. All experiments were conducted on hazelnut leaf discs in an incubator at 25 +/- 1 degrees C, with 16:8 h L:D, at an average daily relative air humidity of 76%. Observations were made twice daily for the immature stages and daily for the adults to determine developmental time, survival and fecundity. The mean developmental time for females was 6.90 days and for males was 7.10 days, and mean adult longevity for females was 11.67 days. The mean total and daily egg production were 12.67 and 1.85 eggs, respectively. The net reproduction rate (R0) was 7.09 females/female, intrinsic rate of increase (rm) was 0.153 female/female/day and mean generation time (T0) was 12.80 days. The mortality rate of immature stages was 0.66% and the sex ratio was 0.51 female.

This study aimed to monitor the present and future developments of the resistance of Tetranychus urticae Koch to fenpyroximate and pyridaben, using the relationship of the LC(50) and slope of the concentration-mortality line in a probit model, for the provision of reliable resistance management tactics. Tetranychus urticae populations were collected from 16 commercial greenhouses, where various crops were cultivated, as well as from 10 apple orchards throughout Korea. The resistance to fenpyroximate and pyridaben of each population was estimated by calculating the median lethal concentration (LC(50)), resistance ratio (RR) and slope of the concentration-mortality regression. Most of the greenhouse populations exhibited moderate levels of resistance, whereas the apple orchard populations showed only low levels, indicating that T. urticae populations in greenhouses were more strongly selected than those in apple orchards. Four population groups were established based on either the habitats (greenhouse and apple orchard) or acaricides (fenpyroximate and pyridaben). To test the hypothesis, "the slope is greatest at low and high levels of resistance," the slopes were regressed as a function of the LC(50), and fitted to a polynomial regression. The polynomial regression model explained this relationship well for the four population groups (p < 0.05), indicating that the development of resistance toward fenpyroximate or pyridaben was consistent with the gradient. A laboratory selection study agreed with the results from both acaricide field populations. These results suggest that the gradient was a good indicator of the susceptibility of T. urticae to genetic variations, which was related to the LC(50). The application of these findings is also discussed in relation to the resistance management of T. urticae.

Tetranychus evansi Baker & Pritchard is an important pest of Solanaceae in several countries. Introduced accidentally to Africa, it presently occurs in many countries of that continent. In some of them, it is considered a key pest. The suspected area of origin of this mite is South America. The objective of the present study was to identify phytoseiid mites on solanaceous plants in association with T. evansi in south and southeast Brazil for introduction in the African continent for use in a classic biological control program. Almost 1,400 predatory mites of the family Phytoseiidae were collected, on 22 solanaceous species. The Amblyseiinae were the most diverse group in this study. Twenty-three of the species found belong to this subfamily, while only three belong to the Typhlodrominae and two to the Phytoseiinae. The most abundant and most frequent phytoseiid species were Phytoseius guianensis De Leon and Galendromus annectens (De Leon) of the Phytoseiinae and Typhlodrominae, respectively. The most frequent and abundant species of Amblyseiinae was Neoseiulus tunus (De Leon). Phytoseius guianensis and N. tunus were never found in association with T. evansi and G. annectens was found only once in association with it. Two factors suggested Phytoseiulus longipes Evans as the most promising predator found in this study. It could walk very well on tomato leaves infested by T. evansi, without being hampered by the profuse webbing produced by the prey and by the trichomes. In addition, several specimens of both sexes including eggs and nymphs of the predator were found associated with T. evansi on three different plant species and in two different periods of the year, when T. evansi was the only arthropod present on the leaves.

Rubber pest mites, Calacarus heveae and Tenuipalpus heveae, reach economic damage levels at the end of the rainy season and the beginning of the dry season in Brazil. Therefore, low humidity adaptation might be an important characteristic for predatory mites to successfully control pest organisms. This study determined the effect of the relative humidity (RH) levels of 30-100% on the hatching of larvae of Amblyseius acalyphus, Euseius citrifolius, Iphiseiodes zuluagai, Metaseiulus camelliae, Agistemus floridanus and Zetzellia malvinae at 25 +/- 0.5 degrees C. These predatory mites are common on rubber trees in the state of São Paulo and might be used for introduction in the major rubber tree production regions in the state of Mato Grosso. At 70% RH or higher, viability was 70% or higher for all species, indicating that their performance might be higher during the rainy season than during the dry season. Eggs of E. citrifolius and M. camelliae presented higher viability at the lower relative humidity levels than those of other species, indicating that these species might have higher chance to persist in the dry season. It is suggested that M. camelliae should be further evaluated for introduction in the state of Mato Grosso, considering that this mite is not yet present in that area.

Strips coated with conidia of Metarhizium anisopliae (Metschinkoff; Deuteromycetes: Hyphomycetes) to control the parasitic mite, Varroa destructor (Anderson and Trueman) in colonies of honey bees, Apis mellifera (Hymenoptera: Apidae) were compared against the miticide, tau-fluvalinate (Apistan) in field trials in Texas and Florida (USA). Apistan and the fungal treatments resulted in successful control of mite populations in both locations. At the end of the 42-day period of the experiment in Texas, the number of mites per bee was reduced by 69-fold in bee hives treated with Apistan and 25-fold in hives treated with the fungus; however mite infestations increased by 1.3-fold in the control bee hives. Similarly, the number of mites in sealed brood was 13-fold and 3.6-fold higher in the control bee hives than in those treated with Apistan and with the fungus, respectively. Like the miticide Apistan, the fungal treatments provided a significant reduction of mite populations at the end of the experimental period. The data from the broodless colonies treated with the fungus indicated that optimum mite control could be achieved when no brood is being produced, or when brood production is low, such as in the early spring or late fall. In established colonies in Florida, honey bee colony development did not increase under either Apistan or fungal treatments at the end of the experimental period, suggesting that other factors (queen health, food source, food availability) play some major role in the growth of bee colonies. Overall, microbial control of Varroa mites with fungal pathogens could be a useful component of an integrated pest management program for the honey bee industry.

It has been shown that many natural enemies of herbivorous arthropods use herbivore induced plant volatiles (HIPVs) to locate their prey. Herbivores can also exploit cues emitted by plants infested with heterospecifics or conspecifics. A study was conducted to test whether green bean HIPVs as well as odours emitted directly by spider mites influenced the orientation behaviour of the predatory mirid bug, Macrolophus caliginosus and its prey, Tetranychus urticae in a Y-tube olfactometer. Our results show that both spider mites and M. caliginosus preferred spider mite infested green bean plants to uninfested plants. For M. caliginosus this response was mediated by HIPVs whereas for T. urticae it was mediated through a composite response to both HIPVs and odours emitted directly by the conspecifics (and their associated products). The results may be of use in practical biocontrol situations, through e.g., plant breeding for improved HIPV production, conditioning of mass-reared predators to appropriate cues, and employment of "push-pull-strategies" by using HIPVs.

The pathogenicity of 52 isolates from several fungus species was studied for the false spider mite Brevipalpus phoenicis. In addition, the main stages during the course of infection by Hirsutella thompsonii, by far the most virulent pathogen, were studied by means of light and electron microscopy. Adult mites were confined to arenas prepared with citrus leaves in acrylic dishes containing agar-water. Conidial suspensions containing 10(8) conidia/ml were applied, except for H. thompsonii, where a concentration of 10(7) conidia/ml was used. The H. thompsonii isolates caused higher mortality, with indices higher than 90%. Observations under the scanning electron microscope (SEM) were performed at 0, 6, 12, 24, 48, 72, and 120 h after application of a H. thompsonii suspension containing 10(7) conidia/ml. Twenty-four hours after inoculation, H. thompsonii conidia were observed attached to the mite's integument. The conidia germinated and penetrated through the base of the setae on the hysterosoma. Colonization occurred after 48 h, as evidenced by mortality. Conidiogenesis occurred after 120 h, with the development of mycelium and conidiophores emerging from the posterior and anterior parts of the mite.

The compatibility of the selective insecticide spinosad (Conserve SC), at rates recommended for thrips control in greenhouses, with release of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) to control spider mites, was investigated in a crop of ivy geranium Pelargonium peltatum, cultivar 'Amethyst 96.' Plants were inoculated with twospotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae), 2 weeks before treatments were applied. There were three treatment variables, each at two levels: predators (released or not), spray application (water or Conserve SC at 2 ml/3.79 l), and timing of spray (1 day before or after predators were released). Twospotted spider mite populations then were sampled twice each week over a three-week period. The application or timing of spinosad had no effect on the ability of the predator to reduce the population of spider mites. Spider mite populations in the no-predator treatment continued to expand over the course of the experiment, while those in the predator-release treatment declined. We conclude that P. persimilis can be used in conjunction with spinosad on ivy geraniums without causing obvious detrimental effects to this predator or leading to a reduction in biological control.

We describe the spatial epidemiology of Varroa destructor infestation among honey bee apiaries in the greater Auckland area of the North Island of New Zealand. The study population was comprised of 641 apiaries located within the boundaries of the study area on 11 April 2000. Cases were those members of the study population declared Varroa-infested on the basis of testing conducted between April and June 2000. The odds of Varroa was highest in apiaries in the area surrounding transport and storage facilities in the vicinity of Auckland International Airport. A mixed-effects geostatistical model, accounting for spatial extra-binomial variation in Varroa prevalence, showed a 17% reduction in the odds of an apiary being Varroa infested for each kilometre increase in the squared distance from the likely site of incursion (95% Bayesian credible interval 7-28%). The pattern of spatially autocorrelated risk that remained after controlling for the effect of distance from the likely incursion site identified areas thought to be 'secondary' foci of Varroa infestation initiated by beekeeper-assisted movement of infested bees. Targeted investigations within these identified areas indicated that the maximum rate of local spread of Varroa was in the order of 12 km/year (interquartile range 10-15 km/year).

Elimination of domestic dust mites (Acariformes: Pyroglyphidae) from the premises is a significant factor of improving the quality of life in individuals with mite-borne sensitization. Some ways of reducing the number of domestic dust mites in the premises are considered.

A variety of reports on mange eradication exist in international literature. Adequate programs are yet to be established in Germany. The commonly used examination of skin scrapings proved to be insufficient. Due to reliable results the pig health service is using Sarcoptes-ELISA (AFOSA GmbH). In the years 2001 and 2002 a Sacoptes suis eradication was accomplished in two sow farms in the Weser-Ems region and since continuously monitored clinical examinations have been used, as well as ELISA testing and skin scrapings. After two years of monitoring a certificate on "unsuspicious for mange" was given to both farms in November 2003 and June 2004. The practical approach will be described. This Sarcoptes eradication is possible even in areas with intensive pig production. When setting up or expanding high health breeding or multiplying herds "unsuspicious for mange" should be one of the important health targets. The practical results with the use of the Sarcoptes-ELISA for monitoring sow farms are promising.

The effect of neem oil (azadirachtin), originating from the tree Azadirachta indica, was investigated as a potential compound to control the poultry red mite, Dermanyssus gallinae. In vitro tests were performed to determine the most appropriate formulation of neem extracts and concentration of the substance to be used. Cardboard traps containing 20% neem oil were placed at the mites' aggregation sites, out of reach of the hens, in a floor system for layers containing approximately 2400 birds. Treated traps were replaced every week for 4 weeks. Throughout the study, the parasite population was monitored by collections of mites with untreated plastic traps. A 92% reduction of D. gallinae was recorded.

We describe an outbreak of rat mite dermatitis that affected 15 employees of an animal research facility. Cases of rat mite dermatitis are infrequently reported, and outbreaks are reported even less. Our case series demonstrates that in contrast to most prior outbreaks, rat mite dermatitis may occur even in modern, well-maintained physical surroundings and thus remains a relevant diagnosis today.

Background: Citations in scientific articles may tend to favor the views presented. We studied whether there is such reference bias in narrative review articles that discuss interventions against house dust mites for people with asthma., Design: Systematic review of reviews identified in a Medline search that expressed an opinion about the clinical effects of physical or chemical intervention methods., Main Outcome Measure: Positive bias was judged to have occurred if the reference list contained a higher proportion of trial references with significant results than among all trials available to the authors (published 2 years or more prior to the review)., Results: Seventy reviews were included, of which 63 (90%) recommended physical interventions. Forty-six reviews had trial references, 4 of these only to chemical interventions. In the remaining 42 reviews, reference bias was detected (P=2 x 10-8). The most quoted trial had only 7 patients per group, its claimed significant result was probably erroneous, and it did not report a clinical outcome. Intervention recommendations were often based on nonrandomized evidence, and the most quoted nonrandomized controlled study had included only 10 patients per group but claimed very positive results., Conclusion: The narrative review articles were severely biased, and their positive intervention recommendations are at variance with the systematic Cochrane Review on this topic and a recent very large trial of physical intervention, both of which failed to find an effect.

Objective: To investigate the distribution of demodex folliculorum and demodex breuis infection in the external auditory meatus of college students, that may to guide prevention and treatment., Method: Ma F. Method was applied to investigate the external auditory meatus secretion demodex folliculorum and demodex breuis infection on 613 college students., Result: Positive date were 11.58%, it was indifferent in fame or male. Cases of the external auditory meatus demodex folliculorum and demodex breuis infection complained constant scratching anitch (67.6%), that was more in positive cases than in negative case., Conclusion: Scratching anitch in external auditory meatus may have close relationship with demodex folliculorum and demodex breuis infection.

The pathogenicity of Beauveria bassiana to one of the major pests of citrus crops, Phyllocoptruta oleivora, was assessed by inoculating mites with different concentrations of conidia (1 x 10(6), 5 x 10(6), 1 x 10(7), 5 x 10(7) and 1 x 10(8)). Treated mites were kept at controlled conditions (25 +/- 0.5 degrees C, 12 h photoperiod and 98% relative humidity) and mite survivorship was evaluated daily. Mortality was found to increase in time and was dependent on the conidia concentration, with values ranging from 24 to 91% for the lowest and highest conidia concentration, respectively. The calculated LC50 on the fifth day was 4.23 x 10(6) conidia/ml. Mean lethal time was 3.98, 9.79, 3.09 and 2.74 days for 5 x 10(6), 1 x 10(7), 5 x 10(7) and 1 x 10(8) conidia/ml, respectively. Conidia were found to adhere all over the mite body surface, especially at the anal region, where vegetative mycelium was found entering the mite body. We noticed the formation of small crystals inside the mite's body that were produced during colonization of the body cavity by the fungus. This is the first report of B. bassiana pathogenicity for this species.

The ecological impact of introduced biological control agents on native species of arthropods is a matter of considerable debate. This study investigated the ability of the non-native predatory mite Neoseiulus californicus to feed on the native Typhlodromus pyri and vice versa, as both species now co-occur in UK orchards. Typhlodromips montdorensis is a candidate for introduction into the UK as a glasshouse biological control agent. The ability of T. montdorensis to feed on the widely used N. californicus was investigated to identify possible intraguild predation, which might influence the effectiveness of either or both species as predators of Tetranychus urticae. Both N. californicus and T. pyri consumed larval stages of each other, but in choice experiments both showed a preference for T. urticae. Both N. californicus and T. montdorensis also fed on each other, but whereas N. californicus again showed a preference for T. urticae, T. montdorensis fed equally on T. urticae and N. californicus. Interactions between N. californicus and T. pyri and N. californicus and T. montdorensis are discussed in relation to their effectiveness as biological control agents in the glasshouse and the natural control of spider mite in the field.

Seventeen isolates of Metarhizium anisopliae (Metschnikoff) Sorokin and two isolates of Beauveria bassiana (Balsamo) Vuillemin were evaluated for their pathogenicity against the tobacco spider mite, Tetranychus evansi Baker & Pritchard. In the laboratory all the fungal isolates were pathogenic to the adult female mites, causing mortality between 22.1 and 82.6%. Isolates causing more than 70% mortality were subjected to dose-response mortality bioassays. The lethal concentration causing 50% mortality (LC5o) values ranged between 0.7 x 10(7) and 2.5 x 10(7) conidia ml(-1). The lethal time to 50% mortality (LT50) values of the most active isolates of B. bassiana and M. anisopliae strains varied between 4.6 and 5.8 days. Potted tomato plants were artificially infested with T. evansi and treated with B. bassiana isolate GPK and M. anisopliae isolate ICIPE78. Both fungal isolates reduced the population density of mites as compared to untreated controls. However, conidia formulated in oil outperformed the ones formulated in water. This study demonstrates the prospects of pathogenic fungi for the management of T. evansi.

Neoseiulus californicus (McGregor) is a promising agent for successful Tetranychus urticae Koch control through conservation techniques, in strawberry crops in La Plata (Buenos Aires, Argentina). In prey-predator interaction, initial relative densities have an important effect on system dynamics. The economic threshold level (ETL) used for this pest in the present study was 50 active mites per leaflet. In our laboratory experiments, initial T. urticae to N. californicus ratio had a significant effect on the population abundance of T. urticae at a 7-day period. When pest/predator ratio was 5/1 (at initial pest densities from 5 to 15 females/leaflet) the final number of active T. urticae/leaflet was significantly lower than the ETL, while at 20 females/leaflet this number did not differ from the ETL. At 7.5/1 ratio, the final number of active T. urticae/leaflet, at initial pest densities from 5 to 15 females/leaflet, reached the ETL without surpassing it. At 10/1 and 15/1 ratios, pest densities exceeded the ETL only at 15 initial T. urticae/leaflet. Most greenhouse and field observations were consistent with the predictions of a graphical model based on experimental results. This predator was very effective in limiting pest densities at a 7-day period and within the range of pest-predator ratios and absolute densities used in this study. Conservation of N. californicus promoting favorable pest/predator ratios may result in early control of T. urticae.

Spinosad is a reduced-risk insecticide derived as a fermentation product from the soil actinomycete Saccharopolyspora spinosa. It is toxic by ingestion and contact and has a unique mode of action on the insect nervous system. Spinosad exhibits a high degree of selective toxicity towards the insect orders Lepidoptera, Diptera and Thysanoptera, but is less toxic to many beneficial arthropods. To determine if spinosad could be valuable as an alternative acaricide for the control of Tetranychus urticae, laboratory toxicity experiments with leaf-disk bio-assays were performed on a laboratory susceptible and several resistant strains. LC50 values were rather high in comparison with newly developed commercial acaricides. Surprisingly, when spinosad was applied to the roots of tomato plants in rock wool, excellent control of spider mites was obtained. Apparently, spinosad has systemic properties and quantities as low as 1 mg/plant could protect tomato plants from mite infestation. Different substrates with varying percentage of clay and organic matter were tested in comparison with rockwool and showed that sufficient control was restricted to the rockwool substrate. Consequently, a dose-response experiment with tomato plants grown in rockwool was set up. The persistence of spinosad toxicity when applied via the roots was determined, and pointed to a long lasting control (up to 30 DAT). Spinosad amounts in leaves after systemic application were determined with an immunological technique to quantify spinosad uptake. Correlations between mite control, spinosad uptake and leaf concentrations can be helpful to determine the necessary dose in field situations.

Persea mite, Oligonychus perseae Tuttle, Baker, and Abatiello, susceptibility to abamectin and milbemectin was evaluated in 2003 to determine baseline susceptibility levels in avocado groves in San Diego and Ventura Counties (California, USA) where more than 70% of the state's avocado production is concentrated. Milbemectin has yet to be used in avocado production in California and abamectin has been available for use since 1999. Baseline susceptibility ratios (in relation to the most susceptible population) of five persea mite field strains to milbemectin varied 2.1- to 2.8-fold at the LC50 and LC90, respectively. The susceptibility of seven field strains to abamectin varied slightly more (2.1- to 3.5-fold) with one strain subjected to seven sprays over the past 4 years showing slight but significant separation of LC50 and LC90's from the most susceptible strain, which is suggestive of the early stages of resistance to this product. Based on these data, baseline susceptibility levels are proposed that might be used to monitor for future persea mite resistance to these chemicals as their use in California avocado production continues.

Interspecific predation and cannibalism are common types of interaction in phytoseiid predator guilds, but the extent and nature of these interactions have not been determined yet in phytoseiid guilds composed of African native and neotropical exotic phytoseiid predators found in cassava habitat in southern Africa. We determined in laboratory experiments the level of cannibalism and interspecific predation among the three phytoseiid mite species Euseius fustis, Iphiseius degenerans, and Typhlodromalus aripo in the absence of food and in the presence of limited or abundant quantities of two food types--Mononychellus tanajoa and maize pollen--commonly found on cassava in Africa. When confined without food, only two T. aripo females laid each two eggs within 5 days, and this species survived longer than I. degenerans and E. fustis. In the presence of con- or hetero-specific larvae or protonymphs, the three species fed more on the former than on the latter, and more on hetero-specifics than on con-specifics. Oviposition rates of the three species did not exceed 0.7 egg/female/day on con- and hetero-specific immatures. Typhlodromalus aripo and E. fustis survived longer on con-specific and hetero-specific larvae and on hetero-specific protonymphs than in the absence of any food, while T. aripo survived longer than the two other species on the same diets. Provision of limited quantity of food decreased interspecific predation rate by I. degenerans and T. aripo, but not by E. fustis, and increased oviposition rate and longevity of all three species. Provision of abundant food, however, eliminated cannibalism by all three species and further reduced interspecific predation rates, but their oviposition and longevity remained relatively unchanged compared with limited food provision. Potential consequences of cannibalism and interspecific predation among phytoseiid mites on cassava for the biological control of M. tanajoa are discussed.

Two types of trap, the BT Trap and PC(TM) pitfall cone trap, were evaluated against the most widely used method of sampling and sieving for their ability to detect low numbers of storage mites (Acarus siro, Tyrophagus longior and Lepidoglyphus destructor) in bulk oilseed rape, under UK maritime conditions. In addition, a synthetic lure (2-nonanone) was incorporated into the two types of trap to assess whether its presence improved trapping performance. The BT traps and PC traps were significantly more effective in detecting low numbers of mites of all species compared with sampling and sieving. The PC trap with synthetic lure was the most effective method. As the PC trap is already widely used for monitoring insects in cereal bulks in the UK, extending its application to include oilseed rape, and to detect mites, would be a logical and cost effective extension of its use.

Psoroptes mites (Acari: Psoroptidae) are important ectoparasites of mammals, and are of particular economic significance as the agents of mange in sheep. To be effective against mites, putative fungal biocontrol agents must be able to operate at the relatively high temperatures and humidities found at the sheep skin surface. To consider this, the growth rates of different isolates of the entomopathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin (Deuteromycotina: Hyphomycetes) were compared and the pathogenicity of these isolates against Psoroptes derived from rabbits (Psoroptes ovis Hering, syn P cuniculi) were evaluated at temperatures between 28 degrees C and 40 degrees C, and when formulated in either Tween 80 or silicone oil. For this study four multi-conidia, arthropod-derived, isolates of M anisopliae were used: from the USA, France, Denmark and Brazil. One single-conidia culture derived from the US isolate was also included in the investigation. Fungal growth was higher at the lower temperatures and none of the isolates grew at 40 degrees C. The growth of the US and single-conidia isolate declined markedly with temperature. In contrast, the Danish, French and Brazilian isolates grew almost as well at 32 degrees C and 35 degrees C as at 28 degrees C and 30 degrees C. The French and Brazilian isolates showed some growth at 37.5 degrees C but the Danish and US isolates did not. The number of fatal infections which resulted from exposure of mites to the fungal isolates was also strongly influenced by temperature. At 30 degrees C all isolates gave between 70 and 90% infection. The number of infections declined with increasing temperature and no infections were seen at 40 degrees C. However, the French and Danish isolates of M anisopliae gave higher numbers of infections than the other isolates at elevated temperatures. When formulated in silicone oil, significantly higher levels of infection were obtained than when formulated in Tween 80, even at the relatively high temperature of 37.5 degrees C. It is suggested that high-temperature adapted isolates of M anisopliae formulated in silicone oil offer good candidates as control agents under the conditions found at the sheep skin surface.

In an attempt to enrich for potentially protective Psoroptes ovis antigens, three separate vaccine trials were conducted in which groups of sheep were immunized three times with various fractions of a soluble extract of P. ovis mites using QuilA as adjuvant. These groups, as well as controls that received adjuvant only, were challenged with P. ovis, and protective immunity was assessed by measuring lesion areas and conducting mite counts 4 and 6 weeks later. All fractions stimulated high titre serum antibodies. Most conferred some protection on sheep with active disease, although there was considerable variation between sheep in all groups, including the controls. Some fractions were more protective than the extract itself, suggesting that the protective components had been concentrated. Indeed the best fraction, obtained by ion exchange chromatography, followed by a gel filtration step, slowed lesion growth to less than a third by 6 weeks after challenge and reduced mite numbers by more than 13 times compared to control sheep vaccinated with QuilA only. However, as judged by polyacrylamide gels, the polypeptide profile of this fraction was still complex, indicating that further work is required to identify the protective components.

The acaricial activity of 56 plant essential oils against poultry house-collected adult Dermanyssus gallinae De Geer was examined using direct contact and fumigation methods. In a filter paper contact bioassay, 100% mortality at 0.07 mgcm-2 was observed in bay, cade, cinnamon, clove bud, coriander, horseradish, lime dis 5F, mustard, pennyroyal, pimento berry, spearmint, thyme red and thyme white oils, whereas the mortality of these oils was significantly decreased at 0.02 mgcm-2. In fumigation tests with adult D. gallinae at 0.28 mgcm-2, cade, clove bud, coriander, horseradish and mustard oils were more effective in closed containers than in open ones, indicating that the effect of these essential oils was largely due to action in the vapour phase. Plant essential oils described herein merit further study as potential D. gallinae control agents.

Sheep scab, which is caused by the mite Psoroptes ovis, is a notifiable disease in Switzerland. In the framework of an epidemiological study in the canton of Schwyz, a sheep scab outbreak on 2 adjacent alpine pastures with 62 flocks (1770 sheep) was followed up clinically, parasitologically and serologically. No mass treatment of the flocks with organophosphates or avermectins had been undertaken before the flocks were taken up to the alpine pastures, but they were treated according to their serological status. Supervised treatment of seropositive judged flocks (at least one seropositive or at least 2 serologically equivocal animals per flock) with Doramectin was undertaken, whilst seronegative judged flocks remained untreated. Sheep returned from the summer pastures in early September 2001 and within three months scab infestation was diagnosed in 53 flocks (85.5%). These infested flocks were scattered all over the canton. Furthermore, the transfer of sheep from 6 infested flocks resulted in the transmission of the disease to 10 new flocks. Infested flocks were kept in quarantine and sanitized. The complexity of the traditional use of shared alpine pastures and the intense, uncontrolled trading with animals render the control of sheep scab difficult.

Integrated pest management programs seek to minimise reliance on pesticides and provide effective long-term control of pests. Cultural control strategies, such as crop rotations, trap and border crops, and weed management, require a thorough understanding of pest host associations. This paper examines the effects of different plant hosts on the persistence and reproduction of blue oat mites, Penthaleus spp., and the redlegged earth mite, Halotydeus destructor (Tucker), which are major agricultural pests in southern Australia. Field and shade-house experiments were conducted testing several crop and plant types. All species survived and reproduced from one mite season to the next when confined to pasture. Canola and a common weed, 'bristly ox-tongue', were suitable hosts for H. destructor and Penthaleus falcatus (Qin and Halliday), whereas Penthaleus sp. x and Penthaleus major (Dugés) failed to persist on these plants. A mixture of wheat and oats sustained P. sp. x and H. destructor, but not P. falcatus or P. major. Lentils were generally a poor host plant for all mite species. These findings show that earth mite species differ in their ability to persist on different plant types, highlighting the importance of distinguishing mite species before implementing control strategies. Results are discussed with respect to cultural control options for the management of these winter pests.

This study tested the effectiveness of benzyl benzoate (BB) in killing Tyrophagus putrescentiae (Schrank) mites when using the method utilized by regular consumers. The efficacy of the BB sprays was determined in laboratory experiments and semi-field experiments with mattress and mattress pad pieces. The mites were counted and their living status determined at different time points microscopically. In the laboratory experiment, the sprays containing either 0.5 %/0.9 % BB with 70 % ethanol or 0.1 % BB with absolute ethanol were highly efficient, resulting in over 90 % mite mortality within 20-30 minutes. In the semi-field experiment, mimicking the home application, the sprays were applied to pieces of a mattress and a mattress pad, and allowed to affect the area for 30 minutes before thorough vacuuming. The recovery of mites was usually less than 10 %. The sprays containing BB were effective in killing the mites in the laboratory, but success was less prominent in the semi-field tests. This method could be used in testing other compounds for their efficacy in killing mites.

Although organic acids represent < 0.5% of honey's constituents, they make important contributions to the organoleptic, physical, and chemical properties of honey. To date, approximately 30 nonaromatic organic acids have been identified in honey, but relatively little attention has been paid to these components. This article reviews the current literature related to the significance of nonaromatic organic acids in honey; it was written with a goal of attracting researchers to study these interesting honey components. Previous research contributions on nonaromatic organic acids in honey may be classified into five main areas: (i) the antibacterial activities of these acids, (ii) the antioxidant activities of these acids, (iii) the use of these acids as possible indicators of incipient fermentation, (iv) the use of these acids for treatment of Varroa infestation, and (v) the use of these acids as factors for the characterization of both botanical and geographical origins of honeys. We conclude that nonaromatic organic acids are of interest for diverse reasons and that there is a particular need for studies regarding their possible antibacterial and antioxidant activities.

Almost 2000 samples of the dried plants and animals used in Chinese traditional medicine were collected from a storehouse in Huainan city, Anhui province, China, where they had been kept for at least 6 months. When examined, every sample was found to contain acaroid mites. The mites included representatives of 44 species belonging to 22 genera and seven families. It seems that samples of Chinese traditional medicine frequently become severely infested with mites while in storage. More importance should be attached to protecting the medicines against mite infestation and to protecting against acariasis those who ingest or simply handle the medicines.

An outbreak of scabies occurred in a ward of a local hospital in Barbastro (Huesca, Spain), between November 2002 and January 2003. The outbreak was linked to a patient infested with mites when he was admitted to the ward on 1 November 2002. The first case had onset of symptoms on 5 November and the last one on 5 January 2003. Seventeen cases were reported: 11 healthcare workers (HCWs) and six patients. The outbreak was attributed to a delay in diagnosis, and lack of individual protection measures by caregivers. The use of short-sleeved coats is an habitual risk practice in this ward. Contact with fomites, animals, infested clothes or intimate contact with people other than their usual partners were dismissed as risk factors for the infestation. The different groups of caregivers in this ward presented a similar risk of becoming infested, and the mechanism of transmission was probably person to person contact. The implementation of specific guidelines for scabies prevention and treatment, as well as an active surveillance system, were fundamental to the control of this outbreak.

A randomised block design study was conducted to evaluate the effects of mange on cattle. Twenty-four Simmentaler Fleckvieh bulls were formed into eight replicates of three bulls based on Day -56 body weight (288-414 kg). Within replicates bulls were randomly allocated to groups G1: uninfested control, G2: infested control or G3: infested, treated with 0.2mg ivermectin/kg (1% ivermectin injection; IVOMEC, Merial) on Day 0. The G2 and G3 bulls were infested with Sarcoptes/Chorioptes mites on Days -56 and -49. Feed consumption was recorded daily throughout the study (Days -56 to 56). Body weights were measured and serum samples collected. Mites were counted at bi-weekly intervals from Day -14 on. The carcasses of the bulls and the leather produced from their hides were evaluated. Differences between variables were declared significant if P

This experiment assessed the efficacy of rotenone and oxalic acid (OA) in an aqueous sugar solution in controlling the honeybee mite Varroa destructor. Colonies were populated with mite-infested brood combs and worker bees. Three rotenone or OA treatments administered during the period with capped brood on 31 July, 14 and 18 August resulted in an average efficacy of 24.10%. In untreated colonies mite mortality averaged 5.40%. No significant differences (P>0.05) were found between the rotenone and OA treatments. Three OA treatments administered on 9, 12 and 18 September resulted in a 77.93% mite mortality. An increase in mite drop (P<0.05) was observed at 2 and 4 days after each treatment. OA applications in broodless colonies resulted in significantly (P<0.001) higher mite mortality rates (98.65% average) than the three treatments of rotenone or OA in colonies with capped brood. The dynamics of mite mortality after each rotenone or OA treatment are discussed in this study.

The efficacy of formic acid in a gel matrix was evaluated in two groups of honeybee colonies. In Group 1, a dispenser with 120 g of formic acid (70%) in gel was placed on the brood combs and another dispenser with the same dose was located on the hive bottom (total dose, 240 g). Group 2 received two doses of 240 g of formic acid (70%) in gel and each application was applied in two dispensers containing 120 g of the formic acid solution each and they were located over the brood chamber (total dose, 480 g). In Group 2, the period between both applications was 15 days, and the efficacies after the first and both applications were calculated. Significant differences were registered for final efficacy between both groups. When final efficacy of Group 1 was compared with efficacy after first application of Group 2, significant differences were found (P=0.0005). Same doses in different positions within the hive have different final efficacy. The higher efficacy was registered when the dispensers were placed over brood combs and on the hive bottom. It is suggested that efficacy is related to dispenser position within the hive.

The acaricidal mycopathogen Hirsutella thompsonii has been found to secrete metabolites that are active against female Tetranychus urticae. Specifically, the rose-colored exudate produced on sporulating cultures of Mexican HtM120I strain sterilized female spider mites in a dose-dependent fashion. Topical application of the exudate resulted in a 100% reduction in mite fecundity over the initial six days of experimentation. Depending upon the exudate dosage, mites partially recovered within 3 and 6 d post-treatment and produced a limited number of eggs. The spider mite active HtM120I exudate contained less detectable HtA toxin than the HtM120I broth filtrate, and it was innocuous when injected into the greater wax moth Galleria mellonella L. larvae. Broth filtrates of HtM120I cultures, although toxic to assayed G. mellonella larvae, did not inhibit mite oviposition to the degree or duration of the exudate preparations. These findings suggest that the factor responsible for suppressing oviposition in female spider mites is linked to the sporulation process and is distinct from the well-characterized HtA produced by vegetative cells.

In order to decrease the variability of formic acid treatments against the honey bee parasite the varroa mite, Varroa destructor (Anderson and Trueman 2000), it is necessary to determine the dose-time combination that best controls mites without harming bees. The concentration x time (CT) product is a valuable tool for studying fumigants and how they might perform under various environmental conditions. This laboratory study is an assessment of the efficacy of formic acid against the varroa mite under a range of formic acid concentrations and temperatures. The objectives are 1) to determine the effect of temperature and dose of formic acid on worker honey bee and varroa mite survival, 2) to determine the CT50 products for both honey bees and varroa mites and 3) to determine the best temperature and dose to optimize selectivity of formic acid treatment for control of varroa mites. Worker honey bees and varroa mites were fumigated at 0, 0.01, 0.02, 0.04, 0.08, and 0.16 mg/L at 5, 15, 25, and 35 degrees C for 12 d. Mite and bee mortality were assessed at regular intervals. Both mite and bee survival were affected by formic acid dose. Doses of 0.08 and 0.16 mg/L were effective at killing mites at all temperatures tested above 5 degrees C. There was a significant interaction between temperature, dose, and species for the CT50 product. The difference between the CT50 product of bees and mites was significant at only a few temperature-dose combinations. CT product values showed that at most temperatures the greatest fumigation efficiency occurred at lower doses of formic acid. However, the best fumigation efficiency and selectivity combination for treatments occurred at a dose of 0.16 mg/L when the temperature was 35 degrees C.

To determine the impact of an acarine predator guild on the abundance of a shared herbivorous prey and its principal exotic predator, a series of surveys were conducted in ca. 200 cassava fields in swamp and non-swamp areas in southwestern Benin, West Africa. For each field, the surveys provided data on the density of a pest arthropod, the cassava green mite Mononychellus tanajoa (Bondar), of an introduced and successfully established natural enemy, the apex-inhabiting predatory mite Typhlodromalus aripo DeLeon, and on occurrence of other predator species that inhabit the leaves and share the same prey. These other predators included one exotic species, Typhlodromalus manihoti Moraes, that is successfully established mainly in swamp areas, and two indigenous species, Euseius fustis (Pritchard and Baker) and Typhlodromalus saltus (Denmark and Matthysse), that are commonly found on cassava in Africa. Our aim was to assess the association between the density of M. tanajoa and that of T. aripo, the most successful predator in terms of establishment and abundance, and subsequently determine how this association was affected by the presence or absence of the other predator species. No obvious density-dependent relationship was found by inspecting the scattergrams of T. aripo versus M. tanajoa densities, but high T. aripo densities did not occur when M. tanajoa densities were low and--during the dry season in February--the densities of M. tanajoa steeply increased when T. aripo numbers were low. Given the establishment of T. aripo in all fields, the presence of other species of predatory mites (T. manihoti, both in swamp and non-swamp areas; T. saltus in absence--as well as presence--of T. manihoti in swamp areas; E. fustis in absence of T. manihoti in non-swamp areas) reduced the density of M. tanajoa by a factor 2-3. Thus in all these cases, the presence of an exotic or indigenous species of predatory mite in addition to T. aripo was associated with lower M. tanajoa density. The density of T. aripo was usually positively affected by the presence of other predator species except for T. saltus in presence of T. manihoti that negatively affected the density of T. aripo in swamp areas, an effect likely mediated by either intraguild predation or competition for food. Path analysis showed that indigenous phytoseiid species were more important in suppression of M. tanajoa populations in cassava fields than previously thought. We suggest that the lack of negative effects of the predator species complex is likely due to differential niche use by the various species which reduces interference among the predators. Manipulative experiments are, however, needed to provide details on the relative importance in M. tanajoa suppression by each species within this acarine predator guild.