Greater Numbers Of Adults Research Articles

Modeling daily energy use in British homes amidst the electricity market crisis: Insights from smart meter and socio-technical data

This study examines the factors influencing daily electricity use in UK homes during the electricity market crisis. Using data from smart meters and socio-technical sources, the research identifies key drivers of electricity consumption, such as household size, weather conditions, and appliance use. Results from a sample of British homes, analyzed through linear mixed effects modeling, show that households with more occupants, greater number of adults, higher heating settings, and fewer energy-saving efforts consume more energy. Weather, housing type, and air conditioning also play significant roles. The findings highlight the importance of integrating smart meter data with other sources to develop effective energy-saving strategies and inform targeted conservation policies.

The effect of socioeconomic factors on health-related quality of life among adults with depressive disorder in the USA

Using data from the Behavioral Risk Factor Surveillance System (BRFSS) a study was conducted to determine the effect of socioeconomic factors of education level, marital status, employment status, and income level on the HRQOL outcomes of activity limitation, physical health, and mental health among adults with depressive disorder in the USA. A greater number of adults with high income level, high education level and married were depression free compared to those with low incomes (39.17% vs. 6.49%), low education level (30.46% vs. 5.8%), and being single (45.35% vs. 8.35%). Also, those with depressive disorder suffered greater physical health problems (11.02% vs. 7.93%) and mental health problems (12.58% vs. 6.26%).

Population dynamics of the pasture leafhopper complex (Hemiptera: Cercopidae) in brachiaria and mombasa grass

Pasture leafhoppers are considered highly important pests in forage grasses in Brazil due to their widespread occurrence. This insect is one of the most relevant pests in pasture degradation. In order for the control of spittlebugs to be efficient, it is important to know the population behavior of the species of this insect, identify the period of greatest occurrence, as well as the climatic and environmental conditions that favor the development of the pest. Thus, this study aimed to evaluate the population dynamics of spittlebugs, at a quantitative level, in Brachiaria decumbens and Panicum maximum pastures, associating the results with meteorological data from the municipality of Conceição do Araguaia, Southeast Pará. To study the population dynamics of spittlebugs, samples were taken every two weeks, in two types of pastures aged between 5 and 7 years, kept under rotational grazing, with a stocking of 1.5 animal units. The method of monitoring nymphs and adults of leafhoppers was adopted, through walking within the observation area. The level of infestation of spittlebugs in both forage species was evaluated and all results were submitted to analysis of variance by the F test. It was found that the species B. decumbens had a greater number of adults and nymphs when compared to the forage species P. maximum. The population dynamics of spittlebugs occur gradually according to climatic conditions, and the period with not-so-high temperatures (22 ºC to 34 ºC) and good rainfall provide an infestation of this insect pest in the pasture.

In Silico and In Vivo Analysis of Amino Acid Substitutions That Cause Laminopathies.

Mutations in the LMNA gene cause diseases called laminopathies. LMNA encodes lamins A and C, intermediate filaments with multiple roles at the nuclear envelope. LMNA mutations are frequently single base changes that cause diverse disease phenotypes affecting muscles, nerves, and fat. Disease-associated amino acid substitutions were mapped in silico onto three-dimensional structures of lamin A/C, revealing no apparent genotype–phenotype connections. In silico analyses revealed that seven of nine predicted partner protein binding pockets in the Ig-like fold domain correspond to sites of disease-associated amino acid substitutions. Different amino acid substitutions at the same position within lamin A/C cause distinct diseases, raising the question of whether the nature of the amino acid replacement or genetic background differences contribute to disease phenotypes. Substitutions at R249 in the rod domain cause muscular dystrophies with varying severity. To address this variability, we modeled R249Q and R249W in Drosophila Lamin C, an orthologue of LMNA. Larval body wall muscles expressing mutant Lamin C caused abnormal nuclear morphology and premature death. When expressed in indirect flight muscles, R249W caused a greater number of adults with wing posturing defects than R249Q, consistent with observations that R249W and R249Q cause distinct muscular dystrophies, with R249W more severe. In this case, the nature of the amino acid replacement appears to dictate muscle disease severity. Together, our findings illustrate the utility of Drosophila for predicting muscle disease severity and pathogenicity of variants of unknown significance.

First observations on surface activity of sandy beach arthropods at the pristine marine reserve of Rocas Atoll, northeastern Brazil

Crustaceans and insects, abundant in the upper zone of sandy beaches, are sensitive to anthropogenic pressures. Thus, to better understand the behavioural changes over time with human impact, studying behavioural and populational parameters in places with pristine conditions is crucial. The Rocas Atoll is one of the first no entry marine reserves in the world, and the first Brazilian marine protected area that harbours unique ecosystems. The aim of the present study was to survey the arthropod fauna associated to the upper zone of a sandy beach at Rocas Atoll, and to study the surface activity of the most abundant species along the transects from the intertidal to the dunes and night/day alternation. Nine arthropod species were observed, including the first record of the marine true bug Halobates sp. (Hemiptera) for Rocas Atoll. Phaleria testacea (Coleoptera), Speziorchestia tucurauna (Amphipoda) and Hecamede sp. (Diptera) represented the most abundant species at the upper zone of Rocas Atoll sandy beaches. Phaleria testacea and S. tucurauna presented marked surface activity predominantly at night time and during low tide. Speziorchestia tucurauna was restricted to the wrack fringe during the entire tidal cycle and the population was represented by a greater number of adults. The high abundance of the fly Hecamede sp. was restricted to daytime and hottest temperatures. This is the first study to assess sandy beach arthropods and their surface activity at Rocas Atoll and provides resources to the understanding of sandy arthropods behaviour under preserved environmental conditions.

Seasonal Abundance and Infectivity of Philaenus spumarius (Hemiptera: Aphrophoridae), a Vector of Xylella fastidiosa in California Vineyards.

The meadow spittlebug, Philaenus spumarius (Linnaeus) (Hemiptera: Aphrophoridae), is a vector of the plant pathogen Xylella fastidiosa; however, its role in recent outbreaks of Pierce's disease of grapevine (PD) in California is unclear. While the phenology and ecology of P. spumarius can help determine its contributions to PD epidemics, both remain poorly described in the North Coast vineyards of California. We assessed the phenology of P. spumarius in the region. Spittlemasses were first observed in February or March, while the emergence of adult spittlebugs did not occur until April or May depending on the year. Analysis of sweep and trap data from 2016 to 2018 revealed significant effects of survey month, vineyard site, and year on adult abundance in sweep and trap surveys. Spittlebug adults were present in the vineyards from April until December, with the greatest number of adults by sweep net in May or June, whereas adults on traps peaked between July and November. Analysis of natural infectivity in groups of field-collected spittlebug adults showed significant difference in transmission rates among months. Spittlebugs successfully transmitted Xylella fastidiosa (Wells) (Xanthomonadales: Xanthomonadaceae) to potted grapevines between July and December. The greatest risk of X. fastidiosa transmission by P. spumarius was in December (60%) followed by October (30%). However, the infectivity patterns of the meadow spittlebug did not align with the historical paradigm of California North Coast PD. We discuss alternative hypotheses in which P. spumarius could play a role in the epidemiology of this disease.

Loneliness in the UK during the COVID-19 pandemic: Cross-sectional results from the COVID-19 Psychological Wellbeing Study.

ObjectivesLoneliness is a significant public health issue. The COVID-19 pandemic has resulted in lockdown measures limiting social contact. The UK public are worried about the impact of these measures on mental health outcomes. Understanding the prevalence and predictors of loneliness at this time is a priority issue for research.MethodThe study employed a cross-sectional online survey design. Baseline data collected between March 23rd and April 24th 2020 from UK adults in the COVID-19 Psychological Wellbeing Study were analysed (N = 1964, 18–87 years, M = 37.11, SD = 12.86, 70% female). Logistic regression analysis examined the influence of sociodemographic, social, health and COVID-19 specific factors on loneliness.ResultsThe prevalence of loneliness was 27% (530/1964). Risk factors for loneliness were younger age group (OR: 4.67–5.31), being separated or divorced (OR: 2.29), scores meeting clinical criteria for depression (OR: 1.74), greater emotion regulation difficulties (OR: 1.04), and poor quality sleep due to the COVID-19 crisis (OR: 1.30). Higher levels of social support (OR: 0.92), being married/co-habiting (OR: 0.35) and living with a greater number of adults (OR: 0.87) were protective factors.ConclusionsRates of loneliness during the initial phase of lockdown were high. Risk factors were not specific to the COVID-19 crisis. Findings suggest that supportive interventions to reduce loneliness should prioritise younger people and those with mental health symptoms. Improving emotion regulation and sleep quality, and increasing social support may be optimal initial targets to reduce the impact of COVID-19 regulations on mental health outcomes.

Development of a 60/60 Guideline for Referring Adults for a Traditional Cochlear Implant Candidacy Evaluation.

To evaluate the effectiveness of a 60/60 referral guideline for identifying patients who should be referred for a cochlear implant candidacy evaluation (CICE), which states patients should be referred if they demonstrate a best ear unaided monosyllabic word score less than or equal to 60% correct and if they demonstrate an unaided pure-tone average in their better ear that is greater than or equal to 60 dB HL. Retrospective review of data from adults who participated in a CICE. A single tertiary medical facility. Five hundred twenty-nine patients who participated in a CICE. CICEs included unaided threshold assessment, unaided speech recognition, and aided word and sentence testing. Ninety-five percent of patients who met traditional indications for a cochlear implant (n = 250) had a pure-tone average that was greater than or equal to 60 dB, while 92% had a better ear unaided monosyllabic word score that was less than or equal to 60%. If used as a screening measure, the 60/60 measure resulted in a 96% detection rate and a 34% false-positive rate for identifying adults who would meet traditional indications for a cochlear implant. Hearing professionals should consider referring patients for a CICE when they meet the 60/60 guideline. It is hoped that provision of this guideline will result in greater numbers of adults being referred for CICEs, improving access to cochlear implants for patients who may benefit from this important technology.

Organic mulch can increase the survival of a weed biological control agent during laboratory mass rearing

ABSTRACTMass rearing agent organisms is a critical component to classical biological control programmes. Maximising survival of each life stage necessitates that ideal, stage-specific conditions are available in the rearing protocol. We investigated a method to improve pupal survival of Pseudophilothrips ichini Hood (Thysanoptera: Phlaeothripidae), a proposed biological control agent of the highly invasive Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae). Specifically, we tested the effect of organic mulch on the number of adults emerging. Either compressed coconut fibre, dried Brazilian peppertree leaves, or dried sphagnum moss were added to the soil surface of potted Brazilian peppertrees. Nothing was added to untreated control plants. Each plant was sealed in a clear acrylic cylinder and 50 s instar thrips were added. The number of adults emerging was compared between mulch treatments. The greatest number of adults emerged from plants with sphagnum moss, with no differences among the other mulches and the control. We confirmed that the majority of thrips pupated in the moss rather than in the soil. Relative humidity was higher in the mulch layers compared to the plant canopy. Sphagnum moss likely provided the most ideal harbourages for thigmotactic pupae and the humid microhabitat minimised desiccation. We discuss the use of organic mulches in ecological contexts and emphasise the benefits of organic mulch in captive rearing operations that involve insects with soil-dwelling stages.

Implementation and outcomes of a new safeguarding pathway for vulnerable adults presenting to sexual health services.

Adult safeguarding is the process of protecting vulnerable adults from harm or exploitation. In 2014, our sexual health clinic implemented a new adult safeguarding pathway, including an adult safeguarding proforma, an electronic database and a monthly adult safeguarding meeting. We conducted a retrospective case note review of patients entered onto the safeguarding database and found that greater numbers of adults were identified as vulnerable following the introduction of this pathway. Many required referral for onward support, highlighting the importance of robust safeguarding procedures in a sexual health setting.

An Evaluation of Plant Genotypes for Rearing Asian Citrus Psyllid (Hemiptera: Liviidae)

The Asian citrus psyllid vectors bacteria responsible for a serious citrus disease known as huanglongbing (also known as citrus greening). Many research endeavors on huanglongbing are dependent on a steady supply of Asian citrus psyllid, which can be facilitated using laboratory or greenhouse colonies maintained on an Asian citrus psyllid host plant. The choice of a plant species may be influenced by the flushing characteristics of a genotype, particularly if the goal is to produce large numbers of psyllids. This is because Asian citrus psyllid is dependent on flush (new young leaves) for reproduction. To expedite rearing, plants can be trimmed to stimulate flush growth. We studied the flushing characteristics of 9 plant genotypes known to be highly susceptible to colonization by Asian citrus psyllid: Afraegle paniculata (Schumacher) Engl., Bergera koenigii L., Citrus aurantiifolia (Christm.) Swingle, C. macrophylla Wester, C. maxima (Burm.) Merr., C. medica L., C. reticulata Blanco, C. taiwanica Tanaka & Shimada, and Murraya paniculata (L.) Jack. (all: Rutaceae). When plants were trimmed at 7 mo after planting, the following produced the greatest number of flush shoots: B. koenigii, C. aurantiifolia, C. macrophylla, and M. paniculata. Pruning plants once or twice before a final trimming at 7 mo after planting did not increase the number of flush shoots produced per plant for any of the genotypes. The number of psyllids produced per flush shoot was assessed on 5 genotypes that produced good quantities of flush: B. koenigii, C. aurantiifolia, C. macrophylla, C. taiwanica, and M. paniculata. Although some significant differences among the genotypes were observed with respect to when new adults first began to emerge and when peak emergence occurred, the differences were relatively small (a day or two). During a winter experiment, numbers of psyllids produced per flush shoot were relatively small, but significantly greater numbers of new adults were produced on C. aurantiifolia than on C. taiwanica or M. paniculata. Greater numbers of adults per shoot were produced during warmer weather, with no significant differences among plant genotypes. Regardless of plant genotype or time of year and for reasons that were not clear, small percentages of adults developed wing deformities. There were no differences in sex ratio, and few differences in abdominal color, among Asian citrus psyllid reared on the tested plant genotypes.

Population Biology of Monarch Butterflies,Danaus plexippus(L.) (Lepidoptera: Nymphalidae), at a Milkweed-Rich Summer Breeding Site in Central Washington

ABSTRACT. The population biology of adult Monarch butterflies (Danaus plexippus) was studied during regular visits over three years (June–September 2013–15) at a milkweed (Asclepias speciosa)-rich site in central Washington. Small numbers of spring migrants colonized the site during June 5–17 each year and produced two adult generations one in early July and the other in late July–August, increasing the population at the site until mid–late August in 2013 and 2014. Greatest numbers of adults occurred in late July and August (20–24 per hour). In 2015 the population fell substantially in early August apparently as a consequence of heat wave conditions in late June–early July adversely affecting survival of second generation immature stages. Mark, release and recapture provided maximum population estimates at the site of 160–190 males, a recapture rate of 25–32% and intervals between tagging and recapture of 5–39 days. Sex ratio was imbalanced in favor of males on all dates ranging from 57–100%. Males patrol...

Reproduction, development and habits of the large turkey louse Chelopistes meleagridis (Phthiraptera: Ischnocera) under laboratory conditions.

The bionomy of Chelopistes meleagridis off the host was observed with the aim of better understanding the aspects of this species' life cycle. For this purpose, C. meleagridis adults were collected and maintained under controlled conditions to reproduce (35°C and RH > 80%), with turkey feathers as the food source. From the offspring of these lice, the development of 150 individuals was observed from the egg to the adult phase. These eggs were divided into two groups of 75 each. After hatching, one group was given a diet composed of feathers while the other received feathers plus skin of the host turkey (Meleagris gallopavo). The "feather + skin" diet resulted in the greatest number of adults, so this diet was given to the next generation of lice reared in vitro, starting from the first instar, to observe their fertility, fecundity and longevity. High reproduction rates were found in relation to other lice of the Ischnocera sub-order, particularly the number of eggs per day and number of eggs produced per female over the lifetime (means of 2.54 and 26.61 eggs, respectively, for wild females and 2.11 and 29.33 eggs for laboratory-reared females). The inclusion of skin in the diet was a determining factor for development to the adult stage, since 48% of the lice fed this diet reached that stage, versus 1.3% that reached maturity fed only with feathers. The development time of the males and females was similar (mean of 29.38 days), without any difference in the sexual proportion of the adults.

Understanding HIV care delays in the US South and the role of the social-level in HIV care engagement/retention: a qualitative study

IntroductionIn a significant geographical shift in the distribution of HIV infection, the US South - comprising 17 states - now has the greatest number of adults and adolescents with HIV (PLHIV) in the nation. More than 60% of PLHIV are not in HIV care in Alabama and Mississippi, contrasted with a national figure of 25%. Poorer HIV outcomes raise concerns about HIV-related inequities for southern PLHIV, which warrant further study. This qualitative study sought to understand experiences of low-income PLHIV on the AIDS Drug Assistance Program in engagement and retention in continuous HIV care in two sites in Alabama.MethodsThe study was designed using grounded theory. Semi-structured interviews with 25 PLHIV explored experiences with care linkage, reported factors and behaviors affecting engagement/retention in continuous HIV care, including socio-economic factors. To triangulate sources, 25 additional interviews were conducted with health and social service providers from the same clinics and AIDS Service Organizations where clients obtained services. Across the narratives, we used the HIV care continuum to map where care delays and drop out occurred. Using open coding, constant comparison and iterative data collection and analysis, we constructed a conceptual model illustrating how participants described their path to HIV care engagement and retention.ResultsMost respondents reported delayed HIV care, describing concentric factors: psychological distress, fear, lack of information, substance use, incarceration, lack of food, transport and housing. Stark health system drop out occurred immediately after receipt of HIV test results, with ART initiation generally occurring when individuals became ill. Findings highlight these enablers to care: Alabama's 'social infrastructure'; 'twinning' medical with social services, 'social enablers' who actively link PLHIV to care; and 'enabling spaces' that break down PLHIV isolation, facilitating HIV care linkage/retention.ConclusionsRyan White-funded programs, together with housing, food and psychological support were pre-conditions for participants' entry and retention in HIV care. The path to achieving continuous HIV care for individuals at risk of lack of entry or delayed HIV care requires robust social-level responses, like in Alabama, that address physical and mental health of clients and directly engage the particular social and economic contexts and vulnerabilities of southern PLHIV.

The Impact of Globalization on Adult Education in a Have-Not Province

This study examines the state of contemporary adult education in New Brunswick. New Brunswick is currently experiencing an increase in unemployment as well as the loss of traditional employment bases. Concurrently, there are greater numbers of adults who are finding themselves with no clear employment direction. One of the places they are ending up is in formal and non-formal adult education programs. Our belief is that the purpose of adult education in the province of New Brunswick has undergone a shift, moving away from an ethic of adult education for personal, social, and political change towards a neo-liberal skills agenda.

Correlates of High Perceived Stress Among Pregnant Hispanic Women in Western Massachusetts

Prenatal psychosocial stress has been associated with adverse pregnancy outcomes, even after controlling for known risk factors. This paper aims to evaluate correlates of high perceived stress among Hispanic women, a group with elevated rates of stress during pregnancy. We conducted this analysis among 1,426 pregnant Hispanic women using data from Proyecto Buena Salud, a prospective cohort study conducted in Western Massachusetts. Cohen's Perceived Stress Scale (PSS-14) validated in English and Spanish was administered in early (mean = 12.4 weeks gestation), mid (mean = 21.3 weeks gestation) and late (mean = 30.8 weeks gestation) pregnancy at which time bilingual interviewers collected data on socio-demographic, acculturation, behavioral, and psychosocial factors. High perceived stress was defined as a PSS score >30. Young maternal age (odds ratio (OR) = 0.6; 95 % confidence interval (CI) 0.4-0.9 for <19 vs. 19-23 years), pre-pregnancy consumption of alcohol (OR = 2.2; 95 % CI 1.4-3.5 for >12 drinks/month vs. none) and smoking (OR = 2.2; 95 % CI 1.3-3.7 for >10 cigarettes/day vs. none) were associated with high perceived stress during early pregnancy. Furthermore, higher annual household income (OR = 0.4; 95 % CI 0.1-0.9 for >$30,000 vs. <$15,000), greater number of adults in the household (OR = 1.8; 95 % CI 1.1-3.0 for ≥3 vs. 1) and language preference (OR = 0.6; 95 % CI 0.4-0.9 for Spanish vs. English) were associated with high stress during mid-pregnancy. Likewise, annual household income was inversely associated with high stress during late pregnancy. Our results have important implications for incorporation of routine screening for psychosocial stress during prenatal visits and implementation of psychosocial counseling services for women at high risk.

Olive Fruit Fly (Diptera: Tephritidae) in California: Longevity, Oviposition, and Development in Canning Olives in the Laboratory and Greenhouse

The biology of olive fruit fly, Bactrocera oleae (Rossi), was studied in the laboratory, greenhouse, and in canning olives, Olea europaea L., in relation to California regional climates. Adults survived in laboratory tests at constant temperatures and relative humidities of 5 degrees C and 83%; 15 degrees C and 59%; 25 degrees C and 30%; and 35 degrees C and 29% for 15, 6, 3, and 2 d without provisions of food and water and for 37, 63, 25, and 4 d with provisions, respectively. In a divided greenhouse, adults survived for 8-11 d in the warm side (36 degrees C and 31% RH daytime); and in the cool side (26 degrees C and 63% RH daytime) 10 d without provisions and 203 d with provisions. A significantly greater number of adults survived in the cool side than the warm side, and with provisions than without. First and last eggs were oviposited in olive fruit when females were 6 and 90 d old, respectively. The highest number of eggs was 55 per day in 10 olive fruit oviposited by 10 28 d-old females, with maximum egg production by 13-37 d-old females. A significantly greater number of ovipositional sites occurred in all sizes of immature green fruit when exposed to adults in cages for 5 d than 2 d. Adults emerged from fruit with a height of > or = 1.0 cm or a volume of > or = 0.2 cm3. More than seven adults per 15 fruit emerged from field infested fruit with a height of 1.1 cm and volume of 0.1 cm3. Larval length was significantly different among the first, second, and third instars and ranged from 0.7 to 1.6, 2.4-4.3, and 4.8-5.6 mm at 14 degrees C; 0.8-1.1, 1.9-2.9, and 3.9-4.4 mm at 21 degrees C, and 0.7-1.3, 2.4-2.9, and 4.4-4.8 mm at 26 degrees C, respectively. Survival of pupae to the adult stage was significantly lower at 26 degrees C than 14 degrees C or 21 degrees C. The period of adult emergence began at 38, 14, and 11 d over a period of 8, 5, and 1 d at 14, 21, and 26 degrees C, respectively. Findings were related to the occurrence and control of California olive fruit fly infestations.

Temperature Affects Emergence of Crataerina pallida (Diptera: Hippoboscidae)

Despite knowledge of parasite biology being essential for host-parasite system functioning to be understood, the life histories of many parasites remain little studied. One example being the hippoboscid Crataerina pallida (Olivier in Latreille, 1812) (Diptera: Hippoboscidae), a nest ectoparasite of the common swift, Apus apus L. (Aves: Apodidae). The factors influencing adult parasite emergence remain unclear. Whether temperature affects emergence was studied by exposing overwintering pupae to differing temperature regimes. At higher temperatures, greater numbers of adults emerged. This indicates that adult hatching is temperature mediated and may be enhanced by host presence. The relationship between C. pallida and their hosts is thus close.

Odour masking of tomato volatiles by coriander volatiles in host plant selection of Bemisia tabaci biotype B

AbstractThe silverleaf whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important pest insects in tomato crop systems worldwide. It has been previously demonstrated that intercropping tomato [Solanum lycopersicum L. Mill. (Solanaceae)] with coriander [Coriandrum sativum L. (Apiaceae)] reduces the incidence and severity of damage caused by B. tabaci. However, it is not yet known how coriander affects the insect′s behaviour. We evaluated the attractiveness of tomato constitutive volatiles to B. tabaci and what effect coriander constitutive volatiles have on the insect′s behaviour. To this end, we conducted three bioassays in a multiple‐choice four‐arm olfactometer (‘×’ type), measuring B. tabaci behaviour when offered tomato and coriander constitutive volatiles presented alone as well as together. We also evaluated the colonisation and establishment of B. tabaci in experimental plots with only single tomato plants and tomatoes intercropped with coriander in a greenhouse. Bemisia tabaci males and females recognised tomato constitutive volatiles as a positive stimulus (kairomonal effect), indicating that semiochemicals from this plant can play an important role in the insect’s host plant selection. Coriander constitutive volatiles reduced the attractiveness of tomato volatiles but no repellency to these volatiles was observed. Greater numbers of adults and nymphs of B. tabaci per plant were observed in tomato monoculture plots than in tomato intercropped with coriander. We suggest that coriander constitutive volatiles have an odour masking effect on tomato volatiles, thus interfering in the host plant selection of B. tabaci.

Differences in the susceptibility of two breeds of dogs, English cocker spaniel and beagle, to Rhipicephalus sanguineus (Acari: Ixodidae)

The objective of this study was to evaluate differences in susceptibility to Rhipicephalus sanguineus (Latreille) of two breeds of dogs: English cocker spaniel and beagle. Three artificial infestations of ticks using a capsule on the back of the dogs were carried out at 15 day intervals. Six dogs of each breed were infested with 100 larvae, 50 nymphs and 20 adults (10 males and 10 females). Every 2 days, the ticks on the dogs were evaluated and the engorged ones counted and collected. The ticks were stored in climatic chambers and inspected every two days for 14 days. The following parameters were recorded: number of engorged ticks, engorgement period, percentage of ecdysis, female weight, conversion of body weight to eggs and larval hatchability. In the ticks recovered from the cocker spaniel, higher percentages of ecdysis of larvae and nymphs, greater number of adults attached and engorged and higher reproductive performance of the females (conversion to eggs and hatchability) were observed. The period of engorgement, number of engorged nymphs and weight of the females did not differ much by breed, but more larvae were attached and engorged in the beagle. In the two breeds, an effect of the successive infestations on the number of engorged larvae and nymphs was observed, which demonstrates the development of a response to the infestation in these stages. However, the percentage of ecdysis and the conversion to eggs was affected only in the more resistant beagles. Based on what was presented, it can be concluded that the animals of the race English cocker spaniel are more susceptible to R. sanguineus than the beagles and that the infestations affect the development of the tick, especially in resistant individuals.