Larvicidal and adulticidal effects and ultrastructural changes of larvae midgut epithelium of musca domestica (diptera: muscidae) fed with bacillus thuringiensis var. kyushuensis

Abstract INTRODUCTION: Musca domestica is resistant to many insecticides; hence, biological control is a suitable alternative. METHODS: We evaluated the lethality of strain Btk176 towards the larval and adult M. domestica and the histopathological effects in the larvae midgut. RESULTS: We observed 99% larval and 78.9% adult mortality within 48 hours of spore ingestion (dosage, 2.4×108 CFU/ml). The histopathological effects were consistent with cytotoxicity. PCR analysis showed the presence of the cry1Ba gene. Transmission electron microscopy revealed a bipyramidal parasporal body. Thurigiensin activity was not detected. CONCLUSIONS: The serovar, Btk176 might be a potential biocontrol agent for houseflies.

Bionomy of two flies of sanitary and forensic importance: Peckia (Sarcodexia) lambens (Wiedemann) and Oxysarcodexia amorosa (Schiner) (Diptera, Sarcophagidae)

ABSTRACTThis study aims to elucidate the bionomy of Peckia(Sarcodexia) lambens and Oxysarcodexia amorosa to provide data for medical, veterinary and forensic entomology analyses. We analyzed larval stage duration (L1–L3), weight of the mature larvae (L3), pupal stage duration, L1–adult duration, adult emergence and viability of larvae and adults of both species. Larval viability of P. (S.) lambens was 82% and the mean duration of the larval stage was 3.51 ± 0.99 days. The mature larvae had a mean weight of 33.67 ± 7.13 mg. The mean duration of the pupal stage was 8.26 ± 0.93 days and the mean duration of the L1–adult was 11.53 ± 1.22 days. Mean lifespan for females and males was 39.33 ± 1.52 and 57.33 ± 4.72 days, respectively. Larval viability of O. amorosa was 76% and mean duration of larval stage was 3.51 ± 0.64 days. Mature larvae had a mean weight of 28.28 ± 3.38 mg. Mean duration of the pupal stage was 10.14 ± 0.63 days and mean duration of the L1–adult was 13.60 ± 0.69 days. Mean lifespan for females and males was 83.66 ± 15.94 and 84.00 ± 19.97 days, respectively. Oxysarcodexia amorosa showed a L1–adult stage longer than P. (S.) lambens; however both species showed low viability. O. amorosa laid more larvae than P. (S.) lambens, this fact may occur because O. amorosa had longer life duration.

Preliminary screening of the larvicidal effect of Brevibacillus laterosporus strains against the blowfly Chrysomya megacephala(Fabricius, 1794) (Diptera: Calliphoridae)

: This study evaluated whether different strains of Brevibacillus laterosporus could be used to control larvae of the blowfly Chrysomya megacephala , a pest that affects both human and animal health.

Chemical composition and insecticidal activity of Cymbopogon citratus essential oil from Cuba and Brazil against housefly / Composição química e atividade inseticida do óleo essencial de Cymbopogon citratus de Brasil e Cuba contra mosca doméstica

Essential oil of Cymbopogon citratus collected from Brazil and Cuba was tested to a chemical characterization and then was tested on the post-embryonic development of Musca domestica. The chemical composition analysis by GC-MS of the oils from Brazil/Cuba allowed the identification of 13 and 12 major constituents respectively; nine of them common to both. In the both oils, the main components were the isomers geranial and neral, which together form the compound citral. This corresponds to a total of 97.92%/Brazil and 97.69%/Cuba of the compounds identified. The monoterpene myrcene, observed only in the sample of Cuba, presented a large relative abundance (6.52%). The essential oil of C. citratus (Brazil/Cuba) was dissolved in DMSO and tested at concentrations of 5, 10, 25, 50, 75 and 100% and citral was prepared by mixing 16.8 mg with 960 µL DMSO. Both essential oils and monoterpene citral were applied topically to newly-hatched larvae (1µL/larva). The results showed a lethal concentration (LC50) of 4.25 and 3.24% for the Brazilian and Cuban essential oils, respectively. Mortalities of larval and newly-hatched larvae to adult periods were dose-dependent for the two both oils as for monoterpene citral, reaching 90%. Both essential oils and citral caused morphological changes in adult specimens.

O óleo essencial de Cymbopogon citratus, coletado no Brasil e em Cuba, foi caracterizado quimicamente e testado no desenvolvimento pós-embrionário de Musca domestica. A análise da composição química dos óleos essenciais (Brasil/Cuba), por Cromatografia Gasosa acoplada ao espectrômetro de massa (GC-EM), permitiu a identificação de 13 e 12 componentes principais, respectivamente; nove deles comuns aos dois. Em ambos os óleos, os principais componentes foram os isômeros geranial e neral, que, juntos, formam o composto citral. Esse corresponde a um total de 97,92%/Brasil e 97,69%/Cuba dos compostos identificados. O monoterpeno mirceno, observado na amostra cubana, apresentou grande abundância relativa (6,52%). O óleo de C. citratus (Brasil/Cuba) foi dissolvido em DMSO, obtendo–se as concentrações de 5, 10, 25, 75 e 100%; e o citral (16,8 mg) foi misturando com 960mL de DMSO. Tanto o óleo essencial como o monoterpeno citral foram aplicados topicamente nas neolarvas (1µL/larva). Os resultados mostraram uma concentração letal (CL50) de 4,25% e 3,24% para o óleo essencial brasileiro e cubano, respectivamente. As mortalidades do período larval e o de neo-larva a adulto foram dose-dependentes, tanto para os óleos como para o monoterpeno citral, podendo chegar a 90%. Ambos os óleos essenciais e citral causaram alterações morfológicas nos espécimes adultos.

First record of acari Arrenurus Dugès, 1834 as a parasite of Odonata species in Brazil

Water mites are common and widespread parasites of some aquatic insects in freshwater habitats. This is the first record of acari Arrenurus Dugès, 1834, as a parasite of Odonata in Brazil. Water mites were sampled from Miathyria marcella (Selys, 1857) and Ischnura fluviatilis (Selys, 1876).

Ácaros aquáticos são parasitas comuns de alguns insetos aquáticos em habitats de água doce. Este é o primeiro registro do ácaro Arrenurus Dugès, 1834, como parasita de Odonata no Brasil. Ácaros aquáticos foram coletados em Miathyria marcella (Selys, 1857) e Ischnura fluviatilis (Selys, 1876).

Temporal distribution of ten calyptrate dipteran species of medicolegal importance in Rio de Janeiro, Brazil

Brazilian studies involving entomological succession patterns in carcasses have been used to describe the necrophagous entomofauna of a determined municipality or region with forensic objectives. Following the same objectives, an ecological study with 10 calyptrate dipterans was carried out during the winter of 2007 and the summer of 2008 in the metropolitan region of the municipality of Rio de Janeiro. The aim of this study was to describe several aspects of the phenology of these species in three neighbouring areas. Carcasses of three domestic pigs (Sus scrofa L.) were used in each season as models for forensic and legal medicine investigations in the region. Temperature, relative humidity and rainfall were measured daily and their relations with population abundance of the colonising species and the decomposition stages were analysed. Ten fly species were recorded to be colonising the carcasses, five of which belonged to the Calliphoridae family, three to the Muscidae, one to the Fanniidae and one to the Sarcophagidae family. Data show preferences of these species for climatic season and decomposition stage, as well as for the studied area and suggest that short distances can significantly influence the abundance of some species.

New records of calyptrate dipterans (Fanniidae, Muscidae and Sarcophagidae) associated with the decomposition of domestic pigs in Brazil

The calyptrate dipterans are the most important decomposers of human cadavers. Knowledge of their species and distribution are of great importance to forensic entomology, especially because of the enormous diversity in Brazil. Carcasses of domestic pigs (Sus scrofa, L) were the experimental models used to attract calyptrates of forensic interest during the winters of 2006 and 2007 and the summers of 2006 and 2008. A total of 24,423 specimens from 44 species were collected (19 Muscidae, 2 Fanniidae and 23 Sarcophagidae), three of which were new records of occurrence and 20 of which were new forensic records for the state of Rio de Janeiro. Fourteen of these species were newly identified as forensically important in Brazil.

Pneumonia por Pneumocystis jiroveci (PPC) em pacientes com SIDA atendidos em hospitais da Baixada Fluminense, Rio de Janeiro, Brasil / Pneumocystis jiroveci pneumonia in patients with HIV infection from hospitals of the Baixada Fluminense, Rio de Janeiro State, Brazil

Objetivos: Os autores investigaram a freqüência de P. jiroveci em pacientes sororreagentes para o Vírus da Imunodeficiência Humana (AIDS) atendidos em hospitais de municípios da Baixada Fluminense, bem como, reconhecer aspectos do padrão epidemiológico da infecção por P. jiroveci nesses pacientes. Método: Para a realização da pesquisa foram coletadas 266 amostras de lavado broncoalveolar de pacientes infectados pelo HIV atendidos em três hospitais da Baixada Fluminense, estado do Rio de Janeiro, Brasil. Resultados: A infecção por Pneumocystis jiroveci foi diagnosticada em 26,3% das amostras, sendo 18% no sexo masculino e 8,3% no feminino. Os gêneros apresentaram freqüências semelhantes (26,8% em homens e 25,3% em mulheres) (X2= 0,07; p>0,05) e ao considerar a infecção por faixas etárias, também não se constatou diferença significativa (H=10,7; p<0,05). Entre eles ainda foram encontrados oito casos de tuberculose representando 3% do total examinado.

Objetives: The authors investigated the P. jiroveci prevalence and the epidemiological pattern of individuals with HIV infection and pulmonary infection concomitantly. Method: Were collected 266 samples of bronchoalveolar lavae of the HIV infection patients from three hospitals from Baixada Fluminense, Rio de Janeiro State, Brazil. Results: The overall prevalence of Pneumocystis jiroveci infection was 26.3%, been 18% in male and 8.3% in female. The sexes showed similar prevalence (26.8% in men and 25.3% in women) and considering the infection stratified by age category, except to female 10-15 years old group, all of them showed infection by the P. jiroveci. Both measurements without significant differences (among sex, X2= 0,07; among age category, H=10,7, p>0,05) respectively. From this survey eight cases of tuberculosis were diagnosed, representing 3.0% of the total examined.

Rearing Chrysomya megacephala on artificial diets composed of varying concentrations of albumin

Larvae of the blowfly Chrysomya megacephala were reared on an artificial diet composed of five different concentrations of albumin (2, 4, 6, 8 and 10 percent) and the control group was fed on putrid bovine meat. No larvae developed in the 2 and 10 percent albumin concentrations. The period from newly hatched larvae to adults reared on 4, 6 and 8 percent albumin was 13.1, 13.1 and 13.6 days, respectively, whereas for the control group, it was 11.2 days. Concentrations of 4, 6 and 8 percent albumin proved viabile for larval periods of 29.3, 44.0 and 57.3 percent, respectively, whereas for the control group, it was 77.3 percent. Pupal viability was 77.3, 36.4 and 83.7 percent, while for the control group, it was 84.5 percent; the newly hatched larvae to adult viability was 21.3, 16.0 and 48.0 percent, respectively, and for the control group, it was 65.3 percent.

O presente trabalho teve como objetivo avaliar o desenvolvimento pós-embrionário de Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) em dietas artificiais à base de albumina nas concentrações de 2 por cento, 4 por cento, 6 por cento, 8 por cento e 10 por cento de albumina e como controle foi utilizada a carne bovina moída putrefata. Não houve desenvolvimento nas dietas de concentração 2 por cento e 10 por cento de albumina. A duração do período de larva a adulto foi 13,1; 13,1 e 13,6 dias, respectivamente, e a do controle foi de 11,2 dias. As dietas artificiais nas concentrações 4, 6 e 8 por cento de albumina apresentaram viabilidades larvais de 29,3; 44,0 e 57,3 por cento, respectivamente e o controle 77,3 por cento; as viabilidades de pupa foram 77,3; 36,4 e 83,7 por cento e o controle 84,5 por cento, respectivamente; as viabilidades de larva a adulto foram 21,3; 16,0 e 48,0 por cento e o controle foi de 65,3 por cento, respectivamente.

Morfologia e duração dos ínstares larvais de Chrysomya putoria (Wiedemann) (Diptera, Calliphoridae), em laboratório / Morphology and duration of larval instars of Chrysomya putoria (Wiedemann) (Diptera, Calliphoridae), in laboratory

Este trabalho visou descrever a morfologia e o tempo de desenvolvimento das larvas de Chrysomya putoria, um importante díptero para saúde pública e medicina legal. As amostras foram coletadas a cada duas horas e, a partir da 56ª hora, as coletas foram realizadas com intervalos de 12 horas até o abandono das larvas maduras do meio de criação. As larvas de C. putoria apresentaram um tempo total de desenvolvimento de 92 horas quando mantidas a 27 °C com comprimento médio de 13,42 mm e características morfológicas peculiares que as diferenciam das outras espécies exóticas e autóctones do Brasil. O esqueleto cefalofaringeano das larvas de terceiro ínstar é robusto e esclerotizado; o gancho labial é completamente pigmentado e curvo, a parte posterior é mais larga que a anterior, mostrando-se levemente pontiagudo. Estas larvas não possuem esclerito oral acessório e o corno dorsal e o ventral apresentam áreas menos pigmentadas. Nota-se uma região não pigmentada em continuação aos cornos, destacando-se no tamanho na região do corno ventral com uma incisão média bem demarcada. Apresentam de 10 a 11 ramificações no espiráculo anterior, peritrema incompleto e presença do botão espiracular, a partir do segundo ínstar.

The objective of this work was to describe the morphology and the developmental time of Chrysomya putoria larvae, a fly of public health and forensic importance. The samples were collected at 2 hr intervals, during the first 56 hr and at 12 hr intervals thereafter, until all mature larvae had abandoned the diet. The total developmental time for Chrysomya putoria larvae at 27 °C was 92 hr, with a mean length of 13.42 mm. The larvae presented unique morphological characteristics which differentiated them from other exotic and autochthonous species found in Brazil. The cephalopharyngeal skeleton of the third instar larvae is robust and sclerotized; the mouth hook is completely pigmented and curved; the posterior end is wider than the anterior, being slightly pointed. The accessory oral sclerit is absent and the dorsal and ventral horns have areas with less pigmentation. It is possible to visualize an area with no pigmentation adjacent to the horns, outstanding in size near the ventral corn with a well delimited medial incision. The anterior spiracles presented 10 to 11 ramifications, open peritrema and the presence of a spiracular bud from the second instar on.

Cryptosporidiosis occurrence in HIV+ patients attended in a hospital, Brazil

A ocorrência de criptosporidiose foi determinada em pacientes HIV+ atendidos na clínica de doenças infecto-parasitárias em hospital de Nova Iguaçu, Rio de Janeiro, Brasil, no período de julho de 1998 a março de 1999. Para a pesquisa, 75 pacientes, portadores ou não de diarréia, foram avaliados. As amostras de fezes foram coletadas e colocadas em solução salina com formaldeído (5 por cento). A técnica de Ritchie modificada foi usada para a pesquisa de oocistos, e os esfregaços foram corados com safranina azul de metileno. Os resultados verificaram 9,33 por cento de amostras positivas, com maior freqüência de casos em pacientes do sexo masculino de 20 a 50 anos, contudo, sem diferença significativa.

Morphological aspects of the larval instars of Chrysomya albiceps (Diptera, Calliphoridae) reared in the laboratory

In order to study the morphology of young Chrysomya albiceps forms, newly hatched larvae were collected at 2 hr intervals, during the first 56 hr; after this time the collection was made at 12 hr intervals. For identification and drawing, larvae were placed between a slide and a coverslip. The cephalopharyngeal skeletons along with the first and last segments were cut off for observation of their structures and spiracles. The larvae present microspines, which are distributed randomly throughout the 12 segments of the body surface; the cenphalopharyngeal skeleton varies in shape and extent of sclerotization according to larval instar; the second and third instars have relatively long processes (tubercles) on the dorsal, lateral and ventral surfaces, with microspine circles on the terminal portion.

Temperature requirements of Chrysomya albiceps (Wiedemann, 1819) (Diptera, Calliphoridae) under laboratory conditions

Chrysomya albiceps specimens were obtained from colonies established with larvae and adults collected at the Federal Rural University in Rio de Janeiro, Seropédica, State of Rio de Janeiro. The larval stage of C.albiceps was allowed to develop in climatic chambers at temperatures of 18, 22, 27 and 32ºC, and the pupal stage was allowed to develop at 22, 27 and 32ºC (60ñ10 per cent RH and 14 hr photoperiod). The duration and viability of the larval stage of C.albiceps at 18, 22, 27 and 32ºC were 21.30, 10.61, 5.0 and 4.0 days and 76.5, 88.5, 98.5 and 99.5 per cent respectively, with mean mature larval weigths of 45.16, 81.86, 84.35 and 70.53 mg, respectively. Mean duration and viability of the pupal stage at 22, 27 and 32ºC were 9.36, 4.7 and 3.0 days and 93.8, 100 and 100 per cent respectively. The basal temperature for the larval and pupal stage and for the larval and adult phase were 15.04, 17.39 and 15.38ºC, corresponding to 65.67, 44.15 and 114.23 DD.