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1.
J Insect Sci ; 21(3)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33974081

RESUMO

The minute pirate bug Orius insidiosus (Say) is an important predator in mango agroecosystems. It attacks several species of thrips, particularly Frankliniella invasor Sakimura, which is considered a species of economic importance in mango. We investigated the effect of six diets on the development, survival, and reproduction of O. insidiosus: 1) first instars of F. invasor, 2) second instars, 3) adults, 4) pollen, 5) pollen plus thrips larvae, and 6) water. Individuals fed on thrips larvae, with or without pollen, completed their immature development significantly faster. Nymphs of O. insidiosus were able to complete their development feeding on pollen only, while individuals that received water as a diet were unable to reach the adult stage. The highest intrinsic growth rate was obtained when O. insidiosus were fed on pollen plus thrips larvae, and the lowest when individuals were fed on thrips adults. Our studies show that a diet of pollen plus F. invasor larvae is optimal for O. insidiosus development and population growth.


Assuntos
Agentes de Controle Biológico , Heterópteros/crescimento & desenvolvimento , Tisanópteros , Ração Animal , Animais , Larva/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Controle de Pragas , Pólen , Comportamento Predatório
2.
Nat Commun ; 12(1): 2503, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947859

RESUMO

Habitat is one of the most important factors shaping organismal morphology, but it may vary across life history stages. Ontogenetic shifts in ecology may introduce antagonistic selection that constrains adult phenotype, particularly with ecologically distinct developmental phases such as the free-living, feeding larval stage of many frogs (Lissamphibia: Anura). We test the relative influences of developmental and ecological factors on the diversification of adult skull morphology with a detailed analysis of 15 individual cranial regions across 173 anuran species, representing every extant family. Skull size, adult microhabitat, larval feeding, and ossification timing are all significant factors shaping aspects of cranial evolution in frogs, with late-ossifying elements showing the greatest disparity and fastest evolutionary rates. Size and microhabitat show the strongest effects on cranial shape, and we identify a "large size-wide skull" pattern of anuran, and possibly amphibian, evolutionary allometry. Fossorial and aquatic microhabitats occupy distinct regions of morphospace and display fast evolution and high disparity. Taxa with and without feeding larvae do not notably differ in cranial morphology. However, loss of an actively feeding larval stage is associated with higher evolutionary rates and disparity, suggesting that functional pressures experienced earlier in ontogeny significantly impact adult morphological evolution.


Assuntos
Ecossistema , Comportamento Alimentar , Larva/crescimento & desenvolvimento , Crânio/anatomia & histologia , Animais , Anuros , Evolução Biológica , Larva/anatomia & histologia , Larva/metabolismo , Osteogênese/fisiologia , Filogenia , Análise de Componente Principal , Crânio/crescimento & desenvolvimento
3.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33834209

RESUMO

The aim of this review is to compile up-to-date information on the superworm, Zophobas morio (F.), regarding its biology and ecology, but also its further potential for use as a nutrient source for food and feed. We illustrate certain basic characteristics of the morphology and bio-ecology of this species, which is marginally considered as a 'pest' in durable amylaceous commodities. More recent data show that Z. morio can be a valuable nutrient and antimicrobial source that could be utilized further in insect-based feed and food production. The inclusion of this species in aquafeed has provided promising results in a wide range of feeding trials, both in terms of fish development and health. Additional data illustrate its potential for use in poultry, indicating that this species provides comparable results with those of other insect species that are used in feed. Moreover, Z. morio can be a viable waste management agent. This review aims to summarize the available data and underline data gaps for future research, toward the potential of the utilization of Z. morio for human food and animal feed. Based on the data presented, Z. morio appears to be a well-promising insect-based protein source, which potential still remains to be unfold.


Assuntos
Ração Animal , Tenebrio , Agricultura , Animais , Besouros/crescimento & desenvolvimento , Besouros/metabolismo , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Nutrientes/metabolismo , Tenebrio/crescimento & desenvolvimento , Tenebrio/metabolismo
4.
Molecules ; 26(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806970

RESUMO

Most insecticides commonly used in storage facilities are synthetic, an issue that generates concerns about food safety and public health. Therefore, the development of eco-friendly pest management tools is urgently needed. In the present study, a 6% (w/w) Hazomalania voyronii essential oil-based nanoemulsion (HvNE) was developed and evaluated for managing Tribolium confusum, T. castaneum, and Tenebrio molitor, as an eco-friendly wheat protectant. Larval and adult mortality was evaluated after 4, 8, and 16 h, and 1, 2, 3, 4, 5, 6, and 7 days, testing two HvNE concentrations (500 ppm and 1000 ppm). T. confusum and T. castaneum adults and T. molitor larvae were tolerant to both concentrations of the HvNE, reaching 13.0%, 18.7%, and 10.3% mortality, respectively, at 1000 ppm after 7 days of exposure. However, testing HvNE at 1000 ppm, the mortality of T. confusum and T. castaneum larvae and T. molitor adults 7 days post-exposure reached 92.1%, 97.4%, and 100.0%, respectively. Overall, the HvNE can be considered as an effective adulticide or larvicide, depending on the target species. Our results highlight the potential of H. voyronii essential oil for developing green nanoinsecticides to be used in real-world conditions against key stored-product pests.


Assuntos
Inseticidas , Laurales/química , Óleos Voláteis , Tribolium/crescimento & desenvolvimento , Triticum/parasitologia , Animais , Emulsões , Inseticidas/química , Inseticidas/farmacologia , Larva/crescimento & desenvolvimento , Óleos Voláteis/química , Óleos Voláteis/farmacologia
5.
Arch Insect Biochem Physiol ; 107(1): e21767, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33835527

RESUMO

Mythimna separata Walker (Lepidoptera: Noctuidae) is one of the major pests that can cause severe damage to grain crops. The development of low-toxicity and high-performance botanical insecticides is becoming the focus of new pesticide research to control M. separata. Tutin, a sesquiterpene lactone compound obtained from Coriaria sinica Maxim, a native Chinese poisonous plant, has antifeedant, absorption, and stomach poisoning against a variety of pests. To understand the toxic effect of tutin on M. separata larvae, we set out to determine their antifeedant, mortality, paralysis, weight change, and to examine the spreading of M. separata hemocytes under different concentrations of tutin treatment. Tissue distribution of the immune-associated gene growth-blocking peptide (GBP) and neuroglian peptide (Nrg) was detected by reverse transcription polymerase chain reaction (PCR). Furthermore, real-time quantitative PCR was carried out to determine the expression profiles of GBP and Nrg after different concentrations of tutin stimulation. Our results revealed that tutin exhibited significant antifeedant and insecticidal activities, paralysis, weight loss to M. separata. Besides, tutin significantly influenced on the morphology of hemocytes and enhanced the expression of GBP and Nrg in M. separata.


Assuntos
Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Picrotoxina/análogos & derivados , Sesquiterpenos/farmacologia , Animais , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Hemócitos/efeitos dos fármacos , Proteínas de Insetos/efeitos dos fármacos , Proteínas de Insetos/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Neuropeptídeos/efeitos dos fármacos , Controle de Pragas , Picrotoxina/farmacologia
6.
Gene ; 787: 145622, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33798679

RESUMO

We clarified the properties of visual opsin genes in the marbled sole (Pseudopleuronectes yokohamae) by cDNA sequencing, quantification of the opsin gene expression from the larval to the juvenile stage, and measurement of the maximum absorption spectra (λmax) using photopigment reconstitution. In the marbled sole eye, at least eight visual opsin genes, lws, rh2-a, rh2-b, rh2-c, sws2a, sws2b, sws1, and rh1, were expressed. Quantitative RT-PCR analysis revealed that the expression of opsin genes increased (lws, rh2-c, sws2a, and rh1) or decreased (rh2-a, rh2-b, sws2b, and sws1) from the larval to the juvenile stage. Notably, rh2-a expression was observed only in pre- to mid-metamorphic stage larvae and disappeared after metamorphosis. Thus, pre-metamorphism-specific expression of rh2-a in the marbled sole suggests that its function is restricted to the developmental stage. The reconstituted RH2-A opsin λmax was 470 nm, which is typical of acanthopterygian species. These results strongly suggest that mid-wavelength-sensitive rh2-a expression was diminished drastically in the marbled sole, probably resulting in a shift of spectral sensitivity during its metamorphosis from the larval to the juvenile stage.


Assuntos
Linguado/genética , Rodopsina/genética , Animais , Olho/embriologia , Olho/metabolismo , Linguado/embriologia , Larva/genética , Larva/crescimento & desenvolvimento , Filogenia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Espectrofotometria , Transcriptoma
7.
Parasitol Res ; 120(5): 1605-1615, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33830362

RESUMO

Parasites can be used as biological tags to assess stock structures in various marine fish species. In the present study, the species composition and infection levels of parasitic nematodes of the genus Anisakis in the skipjack tuna Katsuwonus pelamis were examined in the Northwest Pacific and adjacent seas. A total of 867 third-stage larvae of Anisakis were collected from 112 skipjack tunas captured around Japan and in other subtropical localities. All larvae were identified as A. berlandi, A. pegreffii, A. simplex (s.s.), A. typica, and A. physeteris (s.l.) by the direct sequencing of the mitochondrial cox2 gene and real-time PCR assays targeting the nuclear ITS region. Anisakis species composition differed among northeastern Japan, the Sea of Japan, and other areas (central Japan, the Nansei Islands, and subtropical region), which is largely concordant with previous stock discrimination of skipjack tuna. Molecular phylogenetic analysis resulted in two intraspecific genetic groups in A. simplex (s.s.), one of which occurred almost exclusively in northeastern Japan. This could be a useful indicator for stock discrimination. Skipjack tunas from northeastern Japan were also characterized by a remarkable variety in the intensity of A. simplex (s.s.), suggesting the commingling of individuals with different migration patterns. This idea might be further justified by the geographic distribution of two genetically distinct groups of A. physeteris (s.l.).


Assuntos
Anisaquíase/parasitologia , Anisakis/classificação , Anisakis/isolamento & purificação , Doenças dos Peixes/parasitologia , Atum/parasitologia , Animais , Anisaquíase/epidemiologia , Anisakis/genética , Peixes/parasitologia , Japão/epidemiologia , Larva/crescimento & desenvolvimento , Oceano Pacífico/epidemiologia , Filogenia
8.
Nature ; 591(7850): 408-412, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33692547

RESUMO

Ammocoetes-the filter-feeding larvae of modern lampreys-have long influenced hypotheses of vertebrate ancestry1-7. The life history of modern lampreys, which develop from a superficially amphioxus-like ammocoete to a specialized predatory adult, appears to recapitulate widely accepted scenarios of vertebrate origin. However, no direct evidence has validated the evolutionary antiquity of ammocoetes, and their status as models of primitive vertebrate anatomy is uncertain. Here we report larval and juvenile forms of four stem lampreys from the Palaeozoic era (Hardistiella, Mayomyzon, Pipiscius, and Priscomyzon), including a hatchling-to-adult growth series of the genus Priscomyzon from Late Devonian Gondwana. Larvae of all four genera lack the defining traits of ammocoetes. They instead display features that are otherwise unique to adult modern lampreys, including prominent eyes, a cusped feeding apparatus, and posteriorly united branchial baskets. Notably, phylogenetic analyses find that these non-ammocoete larvae occur in at least three independent lineages of stem lamprey. This distribution strongly implies that ammocoetes are specializations of modern-lamprey life history rather than relics of vertebrate ancestry. These phylogenetic insights also suggest that the last common ancestor of hagfishes and lampreys was a macrophagous predator that did not have a filter-feeding larval phase. Thus, the armoured 'ostracoderms' that populate the cyclostome and gnathostome stems might serve as better proxies than living cyclostomes for the last common ancestor of all living vertebrates.


Assuntos
Fósseis , Lampreias/classificação , Lampreias/crescimento & desenvolvimento , Larva/anatomia & histologia , Animais , Calibragem , Feminino , História Antiga , Lampreias/anatomia & histologia , Larva/crescimento & desenvolvimento , Filogenia , Fatores de Tempo
9.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33686432

RESUMO

Insecticide exposure has been identified as a contributing stressor to the decline in the North American monarch butterfly Danaus plexippus L. (Lepidoptera: Nymphalidae) population. Monarch toxicity data are currently limited and available data focuses on lethal endpoints. This study examined the 72-h toxicity of two pyrethroid insecticides, bifenthrin and ß-cyfluthrin, and their effects on growth and diet consumption. The toxicity of bifenthrin to caterpillars was lower than ß-cyfluthrin after 72 h. Survival was the most sensitive endpoint for bifenthrin, but diet consumption and caterpillar growth were significantly reduced at sublethal levels of ß-cyfluthrin. Using AgDRIFT spray drift assessment, the aerial application of bifenthrin or ß-cyfluthrin is predicted to pose the greatest risk to fifth-instar caterpillars, with lethal insecticide deposition up to 28 m for bifenthrin and up to 23 m for ß-cyfluthrin from treated edges of fields. Low boom ground applications are predicted to reduce distances of lethal insecticide exposure to 2 m from the treated field edge for bifenthrin and ß-cyfluthrin. Growth and survival of fifth-instar monarch caterpillars developing within the margins of a treated field may be significantly impacted following foliar applications of bifenthrin or ß-cyfluthrin. These findings provide evidence that pyrethroid insecticides commonly used for soybean pest control are a potential risk to monarch caterpillars in agricultural landscapes.


Assuntos
Borboletas/efeitos dos fármacos , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Nitrilas/toxicidade , Piretrinas/toxicidade , Animais , Borboletas/crescimento & desenvolvimento , Proteção de Cultivos , Comportamento Alimentar/efeitos dos fármacos , Inseticidas/administração & dosagem , Larva/crescimento & desenvolvimento , Nitrilas/administração & dosagem , Piretrinas/administração & dosagem
10.
Arch Insect Biochem Physiol ; 106(4): e21783, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33719082

RESUMO

Vitamin C (VC) is an essential nutrient for many animals. However, whether insects, including Bombyx mori, can synthesize VC remains unclear. In this article, the optimized HPLC method was used to determine the content of l-ascorbic acid (AsA) in silkworm eggs, larvae and pupae, and the activity of l-gulono-1,4-lactone oxidase (GULO), a key enzyme in VC synthesis. The RNA interference method was used to determine the effect of the BmGulo-like gene on embryonic development and GULO activity in the pupal fat body. The AsA content increased significantly during E144 h-E168 h in the late embryonic stage and P48 h-P144 h in the middle-late pupal stage, in which exogenous VC was not ingested. Furthermore, the body AsA content in larvae fed VC-free feed also increased with larval stage. The GULO enzymatic activity was present in eggs and the fat bodies of larvae and pupae, even when the larvae were reared with fresh mulberry leaves. Moreover, the activity was higher in the later embryonic stages (E144 h-E168 h) and the early pupal stage (before P24 h). The GULO activity in the pupal fat body dramatically decreased when the screened BmGulo-like gene (BGIBMGA005735) was knocked down with small interfering RNA; in addition, the survival rate and hatching rate of eggs significantly decreased 21% and 44%, respectively, and embryonic development was delayed. Thus, Bombyx mori can synthesize AsA through the l-gulose pathway, albeit with low activity, and this synthesis ability varies with developmental stages.


Assuntos
Ácido Ascórbico/metabolismo , Bombyx/metabolismo , Animais , Bombyx/crescimento & desenvolvimento , Hexoses/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Açúcares Ácidos/metabolismo
11.
J Insect Sci ; 21(2)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33764365

RESUMO

Lactic acid is widely used in the food, drugs, cosmetics, and other industries to maintain the microbial stability of low-pH products. However, it is unclear whether lactic acid can affect silkworm (Bombyx mori) growth and reproduction. This study investigated the effects of lactic acid on the growth and reproduction of the silkworm. We analyzed the growth, cocoon quality, and reproductive performance of fifth instar larvae fed on mulberry leaves saturated with different concentrations (0.01, 0.1, 1, and 10%) of lactic acid and the control. Results showed that 0.01, 0.1, and 1% lactic acid supplementation positively affects growth and female cocoon quality, with increased larval weight and female cocoon shell weight compared to the control group. In contrast, 10% lactic acid was toxic to the larvae and significantly decreased growth, leading to larval death. Our study provides a basic reference for the optimal amount of preservatives. In addition, this study can be a desirable intervention for sericulturists and can play an important role in getting high return from silkworm-rearing activities.


Assuntos
Bombyx/crescimento & desenvolvimento , Suplementos Nutricionais , Ácido Láctico , Animais , Peso Corporal , Fertilidade , Larva/crescimento & desenvolvimento , Reprodução
12.
Ecotoxicol Environ Saf ; 214: 112107, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33667734

RESUMO

Perfluorobutanesulfonate (PFBS) pollutant and probiotic bacteria can interact to affect the reproductive outcomes of zebrafish. However, it is still unexplored how the growth and health of offspring are modulated by the combination of PFBS and probiotic. In the present study, adult zebrafish were exposed to 0 and 10 µg/L PFBS for 40 days, with or without dietary supplementation of probiotic Lactobacillus rhamnosus. After parental exposure, the development, growth and viability of offspring larvae were examined, with the integration of molecular clues across proteome fingerprint, growth hormone/insulin-like growth factor (GH/IGF) axis, calcium homeostasis, hypothalamic-pituitary-adrenal (HPA) axis and nutrient metabolism. Parental probiotic supplementation significantly increased the body weight and body length of offspring larvae. Despite the spiking of PFBS, larvae from the combined exposure group still had longer body length. RNA processing and ribosomal assembly pathways may underlie the enhancement of offspring growth by probiotic bacteria. However, the presence of PFBS remarkably increased the concentrations of cortisol hormone in offspring larvae as means to cope with the xenobiotic stress, which required more energy production. As evidenced by the proteomic analysis, the addition of probiotic bacteria likely alleviated the energy metabolism disorders of PFBS, thus allocating more energy for the larval offspring growth from the combined group. It was noteworthy that multiple molecular disturbances caused by PFBS were antagonized by probiotic additive. Overall, the present study elucidated the intergenerational interaction between PFBS and probiotic on offspring growth and health after parental exposure.


Assuntos
Fluorcarbonetos/toxicidade , Lactobacillus rhamnosus , Larva/efeitos dos fármacos , Probióticos/farmacologia , Ácidos Sulfônicos/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Metabolismo Energético/efeitos dos fármacos , Feminino , Sistema Hipotálamo-Hipofisário , Larva/crescimento & desenvolvimento , Masculino , Proteômica
13.
Methods Mol Biol ; 2259: 59-75, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33687709

RESUMO

Anisakis simplex s.s. is a parasitic nematode that causes anisakiasis in humans. L3 stage larvae, which are present in many fish species and cephalopods all over the globe, might be consumed and develop occasionally into the L4 stage but cannot reproduce. Anisakiasis is an emerging health problem and economic concern. In recent years, proteomic methods have gained greater acceptance among scientists involved in parasitology and food science. According to that, here, we present tandem mass tag (TMT)-based shotgun proteomics to define differences in proteomic composition between L3 and L4 development stages of A. simplex s.s.


Assuntos
Anisakis/crescimento & desenvolvimento , Proteínas de Helminto/análise , Proteômica/métodos , Animais , Anisaquíase/parasitologia , Anisakis/química , Anisakis/metabolismo , Cromatografia Líquida/métodos , Proteínas de Helminto/metabolismo , Humanos , Larva/química , Larva/crescimento & desenvolvimento , Larva/metabolismo , Espectrometria de Massas em Tandem/métodos
14.
Arch Insect Biochem Physiol ; 107(1): e21774, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690914

RESUMO

The expression levels of some intrinsic genes, protease activity, and regulation of signaling pathways were distinct during different growth and development stages in the silkworm, Bombyx mori. The silkworm mutant mini was discovered from the normal silkworm strain S8V, and the body-size of the mini mutant was smaller than the wild-type from the second-instar and the difference became more significant in the following stages. In this study, genetic analysis of mini mutant showed that mini mutant was controlled by a single recessive gene, manifested as homozygous lethal. Then, the transcriptome analysis of the mini mutant indicated that 2944 differentially expressed genes (DEGs) were identified from the silkworm in the 48 h of the second-instar, of which 1638 genes in the mini mutants were upregulated and 1306 genes were downregulated. These DEGs were mainly distributed in the biological process, cellular component, and molecular function. The functional annotation based on the KEGG database showed that these genes were mainly clustered in metabolic pathways, fatty acid metabolism pathways, ribosome biogenesis in eukaryotes, and so on. Further analysis indicated that some genes involved in the growth and metabolism including enzyme genes, juvenile hormone, and ecdysone exhibited different transcriptional levels. These results provided new experimental evidence regarding the mechanism of the underlying formation of mini mutants.


Assuntos
Bombyx , Mutação , Transcriptoma , Animais , Tamanho Corporal/genética , Bombyx/genética , Bombyx/crescimento & desenvolvimento , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Genes de Insetos , Proteínas de Insetos/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento
15.
Parasitol Res ; 120(5): 1727-1735, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33686502

RESUMO

Canine peritoneal larval cestodiasis (CPLC) is a little-known parasitological infestation of the peritoneal cavity of wild and domestic carnivores with Mesocestoides spp. larvae. While adult Mesocestoides tapeworms reside within the small intestine, the larvae occasionally penetrate the host's intestinal wall, causing a potentially life-threatening peritonitis. Severity of infection as well as the host response influences the prognosis significantly, and early diagnosis and treatment are essential. However, due to the lack of specific symptoms, this condition is underdiagnosed and, furthermore, no clear effective treatment has yet been described. The aim of this study is therefore to report two clinical cases of CPLC in dogs and to illustrate their clinical presentation and follow-up to serve as a reference for clinicians and researchers alike. Both animals were presented with abdominal distention as their main complaint. They underwent clinical examination, abdominal ultrasonography, abdominocentesis, and laparotomy followed by biochemical, cytological, parasitological, and molecular examination of the collected samples. After surgical lavage, the dogs received anthelmintic treatment with either fenbendazole (FBZ) or praziquantel (PZQ). Overall, timely and prolonged administration of high doses of FBZ seems to be the most effective treatment method. Irrespective, to date, no treatment capable of complete eradication of the infection and prevention of recurrence of disease has been found. In conclusion, further investigation into appropriate treatment plans as well as diagnostic development is needed.


Assuntos
Infecções por Cestoides/parasitologia , Doenças do Cão/parasitologia , Mesocestoides/isolamento & purificação , Peritônio/parasitologia , Animais , Anti-Helmínticos/uso terapêutico , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/tratamento farmacológico , Doenças do Cão/diagnóstico , Doenças do Cão/terapia , Cães , Feminino , Seguimentos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Mesocestoides/efeitos dos fármacos , Mesocestoides/crescimento & desenvolvimento , Resultado do Tratamento
16.
Parasitol Res ; 120(5): 1555-1561, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33655351

RESUMO

Sexually anomalous individuals, typically intersexes or gynandromorphs, bear a mixture of male and female traits. Twelve sexually anomalous individuals of the black fly Simulium (Gomphostilbia) trangense Jitklang, Kuvangkadilok, Baimai, Takaoka & Adler were discovered among 49 adults reared from pupae. All 12 sexually anomalous adults were parasitized by mermithid nematodes, although five additional parasitized adults had no overt external anomalies. Sequence analysis of the 18S rRNA gene revealed that the mermithids, possibly representing a new species, are related to Mesomermis spp., with genetic distances of 5.09-6.87%. All 12 anomalous individuals had female phenotypical traits on the head, thorax, forelegs, midlegs, and claws, but male features on the left and right hind basitarsi. One individual had mixed male and female genitalia. The findings are in accord with the trend that mermithid infections are associated with sexually anomalous adult black flies.


Assuntos
Mermithoidea/isolamento & purificação , Caracteres Sexuais , Simuliidae/parasitologia , Animais , Feminino , Larva/crescimento & desenvolvimento , Masculino , Mermithoidea/classificação , Mermithoidea/genética , Pupa/crescimento & desenvolvimento , RNA Ribossômico 18S/genética , Diferenciação Sexual/fisiologia
17.
J Med Entomol ; 58(2): 956-960, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33710312

RESUMO

Aedes aegypti (Linnaeus, 1762) is the insect vector that transmits several deadly human diseases. Although the egg stage is an important phase of its life cycle, the biology of mosquito egg remains poorly understood. Here, we report our investigations on the chemical factors that induced hatching of Ae. aegypti eggs. Commercial yeast extracts were able to increase egg hatching rate in a dose-dependent manner, with a hatching rate that ranged from approximately 10% with 1 g/liter to 80% with 20 g/liter of yeast extract. Notably, the addition of glutathione, a reducing agent that showed no significant effect on egg hatching by itself, enhanced and stabilized the activity of yeast extract for at least 70 h. Because dissolved oxygen in different treatments was maintained at high levels in a narrow range (92-95%), we proposed that yeast extract contains hatching inducing compound (HIC) which is able to trigger egg hatching independent of dissolved oxygen level. The HIC in yeast extract could prove to be a potential starting point to design an effective tool to forcefully induce mosquito eggs to hatch under unfavorable conditions, functioning as a novel method for vector control.


Assuntos
Aedes/crescimento & desenvolvimento , Aedes/efeitos dos fármacos , Animais , Glutationa/farmacologia , Controle de Insetos/métodos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/crescimento & desenvolvimento , Oviposição/efeitos dos fármacos , Leveduras/metabolismo
18.
Vet Rec ; 188(5): e73, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33666960

RESUMO

BACKGROUND: Nematodirus battus infection is a major health concern in lambs. Development and hatch of infective larvae on pastures is temperature dependent, making model-based risk forecasting a useful tool for disease control. METHODS: Air and 30 cm soil temperature-based risk models were used to predict hatch dates using meteorological data from 2019 and compared to infection dates, estimated from the first appearance of N. battus eggs, on 18 sheep farms distributed across Great Britain. RESULTS: The air temperature model was more accurate in its predictions than the soil temperature model on 12 of the 18 farms, but tended to predict late hatch dates in the early part of the season. CONCLUSION: Overall, the air temperature model appears the more appropriate choice for predicting N. battus peak hatch in the UK in terms of accuracy and practicality, but some adjustment might be needed to account for microclimatic variations at the soil-air interface.


Assuntos
Modelos Estatísticos , Nematodirus , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Infecções por Strongylida/veterinária , Ar , Animais , Fazendas , Larva/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Risco , Estações do Ano , Ovinos , Solo , Infecções por Strongylida/epidemiologia , Temperatura , Reino Unido/epidemiologia
19.
Nat Commun ; 12(1): 942, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574256

RESUMO

The mosquito microbiota impacts the physiology of its host and is essential for normal larval development, thereby influencing transmission of vector-borne pathogens. Germ-free mosquitoes generated with current methods show larval stunting and developmental deficits. Therefore, functional studies of the mosquito microbiota have so far mostly been limited to antibiotic treatments of emerging adults. In this study, we introduce a method to produce germ-free Aedes aegypti mosquitoes. It is based on reversible colonisation with bacteria genetically modified to allow complete decolonisation at any developmental stage. We show that, unlike germ-free mosquitoes previously produced using sterile diets, reversibly colonised mosquitoes show no developmental retardation and reach the same size as control adults. This allows us to uncouple the study of the microbiota in larvae and adults. In adults, we detect no impact of bacterial colonisation on mosquito fecundity or longevity. In larvae, data from our transcriptome analysis and diet supplementation experiments following decolonisation suggest that bacteria support larval development by contributing to folate biosynthesis and by enhancing energy storage. Our study establishes a tool to study the microbiota in insects and deepens our knowledge on the metabolic contribution of bacteria to mosquito development.


Assuntos
Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Mosquitos Vetores/microbiologia , Aedes/genética , Aedes/crescimento & desenvolvimento , Aedes/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Ácido Fólico , Alimentos Fortificados , Trato Gastrointestinal/microbiologia , Regulação da Expressão Gênica , Vida Livre de Germes , Larva/genética , Larva/crescimento & desenvolvimento , Larva/microbiologia , Metabolismo dos Lipídeos , Mosquitos Vetores/crescimento & desenvolvimento , RNA Ribossômico 16S
20.
J Insect Sci ; 21(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560355

RESUMO

In order to investigate a low-cost and sustainable food source, the present study evaluated the use of poultry litter for rearing Tenebrio molitor Linnaeus, 1758 (Coleoptera: Tenebrionidae). The experiment was performed with five diets containing increasing levels of poultry litter (0, 25, 50, 75, and 100%) replacing the control diet and five replicates with 50 larvae per sample unit. Larval growth and development were evaluated and the chemical compositions of diet and T. molitor larvae were determined. Larval development and reproduction efficiency of T. molitor were similar in all treatments. The sole use of poultry litter to feed T. molitor reduced the crude protein of flour by only 8%. Including 50% or more poultry litter in the standard diet is the best-suited formulation for larvae production and incorporation of minerals in the larvae. Mealworm can be grown successfully on diets composed by poultry litter, the diet did not affect survival, growth, and development; however, studies spanning several insect generations should be performed to determine the effects of diet composition on adult fecundity. The knowledge acquired using poultry litter to feed T. molitor will be useful to carry out new research, in addition to evidencing the possibility of low-cost mass rearing of these larvae.


Assuntos
Ração Animal/análise , Tenebrio/química , Animais , Dieta , Larva/química , Larva/crescimento & desenvolvimento , Aves Domésticas , Tenebrio/crescimento & desenvolvimento
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