Effect of Bendiocarb (Ficam^®80% WP) on Entomological Indices of Malaria Transmission by Indoor Residual Spraying in Burkina Faso, West Africa

Context: The vector control is essential in malaria prevention strategies in several endemic countries in Africa including Burkina Faso. The high transmission of malaria occurs during the period of high vector abundance (August to October) in Burkina Faso. Therefore, a vector control strategy based on the use of indoor residual spraying targeting this period should provide effective protection against malaria. This study aimed to evaluate the effect of bendiocarb applied in indoor residual spraying on entomological parameters of malaria transmission in a pyrethroid resistance area in southwestern, Burkina Faso. Methods: CDC light trap and early morning collections by pyrethrum spray catches were performed monthly to determine the change in entomological parameter within malaria vector in sprayed (Diebougou) and unsprayed sites (Dano). The female’s malaria vectors collected by both methods were used to determine their blood feeding pattern, biting and sporozoites rates as well as the malaria transmission risk estimated by entomological inoculation rate. Results: A total of 26,276 mosquitoes (13,555 anopheline and 12,721 other culicines) were collected using both CDC light trap (9158 mosquitoes) and PSC collection methods (17,118 mosquitoes) from June to December 2012. An. gambiae complex was the predominant species collected. An. gambiae was the predominant species collected (P = 0.0005), comprising 88% of the total collected and the most infected species. Malaria vectors densities were significantly lower in sprayed villages (n = 4303) compared with unsprayed villages (n = 12,569) during post-spraying period (P = 0.0012). In addition, mean human biting rate of An. gambiae s.l. and An. funestus s.l. were significantly lower in sprayed areas compared to unsprayed areas (P < 0.05). Overall, malaria vector transmission risk was significant four-fold lower in villages which received IRS (P = 0.0001) whatever the malaria vectors species (An. gambiae s.l. and An. An. funestus s.l.). Conclusions: The results showed that in the sprayed area (Diebougou), vector densities, human biting rates and malaria transmission risks were very lower than unsprayed areas (Dano). The findings also showed a change in vector behavior especially within An. funestus s.l. which became more zoophagic following IRS. The indoor residual spraying could be promoted as a control tool in areas where malaria transmission occurs during a given period of year.

Comparative Evaluation of the Regular Ovitrap vs an Innovated Larvitrap for <i>Aedes</i>Entomological Surveillance in Tapachula

Objective: The objective is to compare a regular ovitrap versus an innovated larvitrap for monitoring Aedes spp. populations. Materials and Methods: A total of 20 regular ovitraps and 20 innovated larvitraps were placed in pairs in 20 houses from the 5 de Febrero neighborhood in Tapachula, Chiapas, Mexico. The innovation consisted in the incorporation of a valve in the lower part of a half tire to drain the contents in a 2 L collection container. The evaluation was carried out during five weeks, collecting eggs and larvae from the ovitraps and innovated larvitraps, respectively. Positivity indexes and insectary production of adult Aedes spp. mosquitoes were compared by collection type. Results: Average positivity index for the five weeks period were 60% for ovitraps and 91.25% for innovated larvitraps. During the five weeks, 4043 Ae. aegypti and 703 Ae. albopictus adult mosquitoes were produced in the insectary from the eggs collected from ovitraps, while from innovated larvitraps were 9014 Ae. aegypti, 1205 Ae. albopictus, and 15 Culex spp. Conclusion: Collection by the innovated larvitrap was more efficient, collecting 3.56 times more Ae. aegypti than with ovitraps, using approximately the same effort in time for replacing the filter paper from traditional 1 L ovitraps. Since the logistics for the storage and placement of larvitraps may still be a disadvantage in comparison with ovitraps, their use could be specifically intended in sentinel sites for mosquito population monitoring for entomological surveillance purposes.

Influence and Expression of Modern Technological Revolution on Entomological Research

Influence and expression of modern technological revolution on entomological research were analyzed from biotechnology and information technology. The application and expression of transgenic plants, transgenic insects, recombinant microorganism, insect tissue culture and informa- tion technology in entomology were discussed in this study, which showed that modern technological revolution brought about a qualitative leap for entomology with a great pushing effect.

Data Processing System （DPS） software with experimental design, statistical analysis and data mining developed for use in entomological research

A comprehensive but simple-to-use software package called DPS （Data Pro- cessing System） has been developed to execute a range of standard numerical analyses and operations used in experimental design, statistics and data mining. This program runs on standard Windows computers. Many of the functions are specific to entomological and other biological research and are not found in standard statistical sottware. This paper presents applications of DPS to experimental design, statistical analysis and data mining in entomology.

An initial study of insect succession on decomposing rabbit carrions in Harare,Zimbabwe

Objective:To investigate insects visiting sun exposed and shaded decomposing rabbit carcasses and to establish the relationship between insects and carcasses which may be of forensic importance in Harare.Methods:Two rabbits weighing 2.3 kg and 2.5 kg were killed by sharp blows on the head.One was exposed to the sun while the other was placed under shade.The carcasses were allowed to decompose and insects were collected twice a day for the first week and thereafter once a day up to the end of the 7 weeks.Maggots were also collected from the decomposing carcasses and reared.Results:Five dipteran families(Galliphoridae,Muscidae,Sarcophagidae,Phoridae and Drosophilidae)were identified from the sun-exposed carcass.Species collected included Lucilia cuprina(L.cuprina),Chrysomya albiceps(C.albiceps),Musca domestica,Sarcophaga sp.and Drosophila sp.Four families(Calliphoridae,Muscidae,Phoridae,Anthomyiidae)were identified from the shaded carcass.Representatives of these families included L cuprina,C.albiceps,Musca domestica,and Hydrotaea sp.Three Coleopteran families(Histeridae,Cleridae and Dermestidae)were identified from hodt carcasses.The observed species were Saprinus sp,Necrobia rufipes and Dermestes sp.Fomicidae(Hymenoptera)was represented by only one species(Pheidoie sp.)Flies which emerged from the rearing units were L cuprina,Lucilia sp.,C.albiceps,Sarcophaga sp.and Sepsis sp.).Conclusions:Of the dipteran species collected during the study,L cuprina and C.albiceps could be important for further forensic studies since they were collected from the carcasses and also observed from the rearing units.

A Biological Restoration Model for Contaminated Coastal Marshes and Islands Using the Life Cycle of Acheta domesticus to Establish Environmental Sustainability

Insects such as Acheta domesticus account for over half of marsh fish and migratory bird diet. Therefore, insects are very important to marsh and island ecosy stems and are susceptible to oil contamination, but little research has been done to study the effects of oil spills on cricket populations. The purpose of this experiment was to determine the effects of an oil spill event on Acheta domesticus mortality and hatch rate to establish environmental sustainability. The treatment groups included 0% oil contamination, 5% oil contamination and 10% oil contamination. The scientist counted the number of deaths in two-week, four-week, and six-week-old crickets after oil contamination. In addition, the scientist counted the number of hatchlings among treated cricket eggs. Error bar lines in the results section supported the scientist’s hypothesis that the crickets would be affected by oil contamination. In fact, over 90% of the 10% oil treatment group died and over 80% of the 5% oil treatment group died after five days of oil contamination in the six-week-old experiment. The scientist used a Gas Chromatography Mass Spectrometer to determine if benzene, toluene, ethylbenzene, or xylene (total) were present in the sediment samples. BTEX exposure is suspected to possibly cause insect mortality. These volatile organic compounds were present in the samples and were found in higher quantities in samples with higher concentrations of oil. The highest quantity of volatile organic compounds present was xylene. After studying the population dynamics of the tested Acheta domesticus, the scientist found that the two-week and four-week-old crickets’ survivability could fit a linear model while the six-week-old crickets fit an exponential model. The scientist used these models to observe how long it took each treatment group to approach zero, and the oiled groups grew closer to a population of zero significantly faster. For example, it took about twenty-seven days for the 10% treatment group’s population to approach zero whereas the control, 0% treatment group, took about seven days in the two-week-old cricket experiment. Overall, the six-week-old crickets had the highest mortality, and the cricket egg experiment resulted in extremely low hatch rate. Specifically, the highest number of crickets that hatched in an oiled replication either 5% or 10% oil was eight out of the five thousand eggs laid. Since the adult crickets are the most physically able to reproduce and the cricket eggs had low hatch rates, the cricket population would significantly decrease after an oil spill with 5% or more soil contamination. However, if the plant matter that crickets consume is still present in their environment, they may be able to recover.

Improvement and Exploration of Teaching Methods for General Entomology in Agriculture and Forestry Colleges and Universities

According to characteristics of General Entomology and existing problems in teaching process,it came up with methods and countermeasures for improving teaching General Entomology,including improving practical ability of students through enhancing all links of practice teaching,and stimulating learning interest of students through improving methods of course examination.

Characterization of insect-fauna of the free-ranging urban dog, Canis domesticus (L.) carcass in tropical region of Pakistan: A tool for forensic entomology

As the authors’ request, the following paper published in Vol.1, No.2, 29-37, 2013 has been withdrawn from the website.

Abnormal Succession of Insect Fauna on Pig Carcasses in Tandil (Argentina, Buenos Aires Province)

This project was an attempt to reconstruct a death in dubious circumstance which happened in December 2002 in Tandil (Buenos Aires Province). Although the body was in open air, the entomological expertise discovered signs of delayed colonization. In this experiment, pig carcasses used as models to reconstruct the case. One was placed in shadow and another in sunlight (control). The hypothesis was that the climate and the topography affect the necrophagous insect succession in a mountain site. The families of Coleoptera found on the baits were: Silphidae, Dermestidae, Cleridae, Histeridae;of Díptera: Calliphoridae, Sarcophagidae;Asilidae;of Hymenoptera: Formicidae, Encyrtidae and Vespidae.

Letter to the Editor

Open-access journals;Advances in

Using DNA Sequences and Phylogenetic Trees as Tools for Teaching Entomology to Undergraduate Students: A Simple Approach

This technical note aims to show how any instructor teaching entomology can use the Basic Local Alignment Search Tool (BLAST) and the “one click” mode of Phylogeny.fr to teach undergraduate students about insect DNA similarity in a simple way. Teaching an entomology course requires the use of numerous tools to help students grasp different concepts. Knowing that there are more than one million described species of insects means that teaching students about insect identification and taxonomy can be challenging. However, here we present two easy exercises that could be used as classroom or take-home assignments to demonstrate various levels of DNA similarity among different insect taxa. Such exercises unlock students’ creativity and break the barrier of fear of bioinformatics. Moreover, they open up new ways for them to understand insect taxonomy through molecular biology and allow them to develop new skills that contribute to strengthening their scientific performance in the future, especially when they do research as graduate students. Finally, this note is an example of how to integrate simple bioinformatics tools into the teaching of entomology.

Seasonality of insect succession on exposed rabbit carrion in Guangzhou, China

Succession patterns for insect fauna, spanning four seasons, on rabbit carcasses were studied in Guangzhou China from 2006 to 2008. A total of 49 taxa belonging to three orders and 15 families were collected and identified. Four decomposition stages were recognized： fresh, bloated, decay and dry stage. Taxa diversity was higher in bloated and decay stages than fresh and dry stages. Internal and ambient temperatures were measured. Maximum internal temperature arrived earlier in warmer seasons. The sequence of insect succession in this study follows the same general patterns： the Diptera peaked initially, and the Coleoptera peaked later. Chrysomya megacephala was the dominant species in four seasons. Its time point of different development stages on carrion could be the most important indicators for PMI （postmortem interval） estimation in Guangzhou. Yearly and seasonal differences in activities of insects were compared. Alpha diversity indices were calculated. There were no significant differences in Shannon-Wiener index, evenness （J） and dominance （C） between seasons and years. From the Jaccard similarity index, the highest similarity was between winter and spring, while the lowest was between summer and winter. Some species occurring exclusively in one season may be important to characterize different seasons. A list of the insect taxa associated with above-ground rabbit carrion during the four seasons was compiled, which can be used for estimating time since death in similar bio-climate areas.

A brief review of forensically important flesh flies (Diptera: Sarcophagidae)

Forensic entomology could provide valuable data for the minimum postmortem interval (PMImin) estimation and other relevant information,such as causes and circumstances of death.Some representatives of flesh flies are one of the dominant necrophagous insects during early stages of decomposition,demonstrating unique biological characteristics compared with other necrophagous flies.Moreover,they lead to global health concerns as carriers of various pathogenic micro-organisms,and dominantly result in the traumatic myiasis.Thus,sarcophagid flies are considered important in decomposition processes for PMImin estimation.However,the utility of sarcophagid flies has been seriously hampered by limited ecological,biological and taxonomic knowledge of them.The aim of this paper is to provide a brief review on the species,distribution and biological habit of forensically important sarcophagid flies.In addition,the relation between traumatic myiasis and flesh flies,molecular identification methods and developmental pattern of flesh flies are summarized.

Identification of forensically important blow fly species （Diptera： Calliphoridae） in China by mitochondrial cytochrome oxidase I gene differentiation

Unambiguous and rapid sarcosaphagous insect species identification is an essential requirement for forensic investigations. Although some insect species are difficult to classify morphologically, they can be effectively identified using molecular methods based on similarity with abundant authenticated reference DNA sequences in local databases. However, local databases are still relatively incomplete in China because of the large land area with distinct regional conditions. In this study, 75 forensically important blow flies were collected from 23 locations in 16 Chinese provinces, and a 278-bp segment of the cytochrome oxidase subunit I gene of all specimens was successfully sequenced. Phylogenetic analysis of the sequenced segments showed that all Calliphorid specimens were properly assigned into nine species with relatively strong supporting values, thus indicating that the 278-bp cytochrome oxidase subunit one region is suitable for identification of Calliphorid species. The clear difference between intraspecific threshold and interspecific divergence confirmed the potential of this region for Calliphorid species identification, especially for distinguishing between morphologically similar species. Intraspecific geographic variations were observed in Lucilia sericata （Meigen, 1826） and Lucilia caesar （Linnaeus, 1758）.

Development of Chrysomya megacephala at constant temperatures within its colony range in Yangtze River Delta region of China

Chrysomya megacephala (Fabricius,1794) is the most abundant and predominant species which arrives and colonizes a cadaver first in most parts of China.Therefore,its growth and development patterns have great implications in the estimation of the minimum postmortem interval (PMImin).In this study,C megacephala was collected from the Yangtze River Delta region and reared at seven constant temperatures ranging from 16 ℃ to 34 ℃.The developmental duration and accumulated degree hours,larval body length and morphological changes of C.megacephala were examined.Furthermore,we constructed three developmental models,isomorphen diagram,isomegalen diagram and thermal summation model,which can be used for estimating PMImin.The developmental durations of C.megacephala at 16 ℃,19 ℃,22 ℃,25 ℃,28 ℃,31 ℃ and 34 ℃ are (794.8 ± 14.7),(533.2 ± 10.1),(377.8 ± 16.8),(280.8 ± 15.1),(218.9 ± 8.5),(190.8 ± 10.1) and (171.8 ± 6.8) h,respectively.The developmental threshold temperature D0 is (11.41 ± 0.32) ℃,and the thermal summation constant K is (3 418.7 ± 137.0) degree hours.Regression analysis was conducted to obtain equations of the variation in larval body length with time after hatching,and variation in time after hatching with body length.Moreover,our study divides the intra-puparial morphological changes of C.megacephala into 11 sub-stages,and provides the time range experienced by each sub-stage.The results of this study provide fundamental development data for the use of C.megacephala in PMImin estimations.

To eat or get heat： Behavioral trade-offs between thermoregulation and feeding in gregarious necrophagous larvae

The thermoregulation behavior ofLucilia sericata larvae （Diptera： Calliphori- dae）, a necrophagous species that feeds on vertebrate cadavers, was investigated. These larvae require high heat incomes to develop, and can elevate temperatures by forming large aggregates. We hypothesized that L. sericata larvae should continue to feed at temperatures up to 38 ℃, which can be reached inside larval masses. Thermal regulation behavior such as movement between a hot food spot and colder areas was also postulated. The hypotheses were tested by tracking for 1 h the activity of single, starved third instar larvae in a Petri dish containing 1 food spot （FS） that was heated to a constant temperature of 25 ℃, 34 ℃ or 38 ℃ with an ambient temperature of 25 ℃. The influence of previous conspecific activity in the food on larval behavior was also tested. The crops of larvae were dissected to monitor food content in the digestive systems. Based on relative crop measurements, larvae fed at all food temperatures, but temperature strongly affected larval behavior and kinematics. The total time spent by larvae in FS and the duration of each stay decreased at high FS temperature. Previous activity of conspecifics in the food slightly increased the time spent by larvae in FS and also decreased the average distance to FS. Therefore, necrophagous L. sericata larvae likely thermoregulate during normal feeding activities by adjusting to local fluctuations in temperature, particularly inside maggot masses. By maintaining a steady internal body temperature, larvae likely reduce their development time.

Effect of low temperature in the development cycle of Lucilia sericata (Meigen) (Diptera, Calliphoridae): implications for the minimum postmortem interval estimation

Knowledge of necrophagous insects' developmental data is necessary for the forensic entomologist to estimate a reliable minimum postmortem interval (PMImin).Among the most represented necrophagous species,Lucilia sericata (Diptera,Calliphoridae) is particularly interesting.It is regularly identified in samples,with a predominance in summer,and is commonly used by analysts of our entomology department (Institut de Recherche Criminelle de la Gendarmerie Nationale) to estimate the PMImin with the accumulated degree days (ADD) method.This method requires the mathematical lower thermal threshold to be known.This value dictates the quality of the applied ADD method but cannot be considered as fixed,especially when insect development occurs at temperatures close to the biological threshold.In such conditions,it is necessary to study the influence of such temperatures on development rate,as well as the consequences of estimating the period of first oviposition on cadavers,when using the ADD method.Seven replicate rearings were conducted at six different temperatures: 30 ℃,24 ℃,18 ℃,15 ℃,12 ℃ and 10 ℃.Time of development and time of emergence were recorded.The effect of low temperature on the development cycle and the reliability of the ADD method under this entire temperature spectrum were studied using different linear regression models.Calculated durations of total insect time development and experimental rearing duration were then compared.A global linear model cannot be used on the whole temperature spectrum experienced by L.sericata without resulting in an overestimation at some temperatures.We found a combination of two linear regression models to be suitable for the estimation of the total development time,depending on the temperature experienced by L.sericata.This approach allowed us to obtain a variation lower than 2% at 12 ℃ and 10 ℃ between the calculated duration and experimental duration of development.In comparison,the results obtained with a global model show a variation higher than 3% at 12 ℃ and 10%at 10℃.

The maximum likelihood identification method applied to insect morphometric data

To distinguish species or populations using morphometric data is generally processed through multivariate analyses, in particular the discriminant analysis. We explored another approach based on the maximum likelihood method. Simple statistics based on the assumption of normal distribution at a single variable allows to compute the chance of observing a particular data （or sample） in a given reference group. When data are described by more than one variable, the maximum likelihood （MLi） approach allows to combine these chances to find the best fit for the data. Such approach assumes independence between variables. The assumptions of normal distribution of variables and independence between them are frequently not met in morphometrics, but improvements may be obtained after some mathematical transformations. Provided there is strict anatomical correspondence of variables between unknown and reference data, the MLi classification produces consistent classification. We explored this approach using various input data, and compared validated classification scores with the ones obtained after the Mahalanobis distance-based classification. The simplicity of the method, its fast computation, performance and versatility, make it an interesting complement to other classification techniques.

The uses of Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) in forensic entomology

Chrysomya megacephala (Fabricius,1794) occurs on every continent and is closely associated with carrion and decaying material in human environments.Its abilities to find dead bodies and carry pathogens give it a prominence in human affairs that may involve prosecution or litigation,and therefore forensic entomologists.The identification,geographical distribution and biology of the species are reviewed to provide a background for approaches that four branches of forensic entomology (urban,stored-product,medico-criminal and environmental) might take to investigations involving this fly.

Chrysomya chani Kurahashi (Diptera: Calliphoridae), a blow fly species of forensic importance: morphological characters of the third larval instar and a case report from Thailand

Blow flies are worldwide the most important insects from a forensic point of view.In Thailand,aside from the two most common species,Chrysomya megacephala (F.) and Chrysomya rufifacies (Macquart),Chrysomya chani Kurahashi was also found to be of forensic importance.We present a case of a human female cadaver in its bloated stage of decomposition,discovered at Pachangnoi Subdistrict,northern Thailand.Entomological sampling during the autopsy displayed an assemblage of numerous dipteran larvae.Macroscopic observations showed the coexistence of third instar larvae of the three blow flies C.megacephala,Chrysomya villeneuvi Patton,an unknown blow fly species and one muscid,Hydrotaea sp.The minimum post-mortem interval was estimated to be six days,based on the developmental rate of C megacephala.The ID of the unknown larva,which is the focus of this report,was revealed later as C.chani by DNA sequencing,using a 1205 bp of cytochrome c oxidase subunit Ⅰ (COⅠ).The occurrence of C.chani on a human body revealed the need to analyse and describe the morphology of its immature stage,to enable forensic entomologists to identify this fly species in future cases.The morphological examination of the third instar was performed,revealing peculiar characteristics: protuberant tubercles encircling abdominal segments;9-11 lobes on the anterior spiracle;six prominent pairs of tubercles along the peripheral rim of the eighth abdominal segment;a heavily sclerotized complete peritreme of the posterior spiracles.A key to differentiate the third instar of blow flies of forensic importance in Thailand is provided.