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Sample records for larvae diabrotica virgifera

  1. Synthetic feeding stimulants enhance insecticide activity against western corn rootworm larvae, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    In behavioral bioassays, the addition of a synthetic feeding stimulant blend improved the efficacy of the insecticide thiamethoxam against neonate western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae. In 4-h bioassays, the concentration of thiamethoxam required for 50% mortality (LC...

  2. Neonate larvae of the specialist herbivore Diabrotica virgifera virgifera do not exploit the defensive volatile (E)-ß-caryophyllene in locating maize roots

    Science.gov (United States)

    The behavior of the neonate larvae of Diabrotica virgifera virgifera LeConte (western corn rootworm, WCR) was assessed in presence of maize root constitutively emitting (E)-ß-caryophylene (EßC). This root volatile has been shown to attract both second instar WCR and insect-killing nematodes, offerin...

  3. Potential damage costs of Diabrotica virgifera virgifera infestation in Europe - the 'no control' scenario

    NARCIS (Netherlands)

    Wesseler, J.H.H.; Fall, E.H.

    2010-01-01

    he Western Corn Rootworm (WCR or Dvv., Diabrotica virgifera virgifera Le Conte) was first detected in Europe in the early nineties in Serbia. Since then the beetle has spread to more than 15 European countries. We assess the potential damage costs of the invasive species Diabrotica virgifera

  4. Management of Western Corn Rootworm (Diabrotica virgifera virgifera

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    Ivan Sivčev

    2012-01-01

    Full Text Available Western corn rootworm (WCR was registered for the first time in Europe near the Surčininternational airport in Serbia in 1992. The spread of WCR on the territory of Serbia and itspopulation density increased fast. The Serbian territory was entirely populated in the followingfew years, while major damages occurred on corn grown for two or more years inthe same field. Data on damages caused to over 140,000 ha under corn until 1999 were collectedby organized monitoring. After 2000 and 2003, population abundance of D.v. virgifera,as well as the number of damaged corn fields, significantly decreased due to droughtand application of crop rotation. Corn rootworm has one generation per year. It overwintersin the egg stage. Under the climatic conditions of Serbia larvae hatching starts aroundMay 15th. The highest number of larvae on root is observed around June 20th when feedingis most intensive and plants become lodged as they lose roots. First adults emerge bythe end of June. Their abundance increases during July and reaches maximum by the endof the month. From the second decade of August the abundance decreases. Adults arepresent in the field until the first frosts. Larvae are much more harmful and significant thanadults. Larvae feed on roots or into roots by boring. Roots can be entirely destroyed underheavy attack and the host plants lodged already at the end of June. Under our climatic andagrotechnical conditions, adults are sporadic pests. Adults are a threat only when sowing isdone after the optimal sowing date or in case of stubble corn sowing.Crop rotation is an efficient and most widespread means of WCR control. No damageon corn grown in crop rotation has been registered in Serbia for now. In the first year of productioncorn does not require protection from Diabrotica virgifera virgifera LeConte larvae.Several insecticides have performed high efficacy by application at sowing and havebeen registered for commercial use. On the other hand, soil

  5. Development of the Western corn rootworm, Diabrotica virgifera virgifera in soil

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    Ľudovít CAGÁŇ

    2016-12-01

    Full Text Available Monitoring of developmental stages of the Western corn rootworm (WCR (Diabrotica virgifera virgifera is an important aspect of its control. In the experiment there were analysed randomly selected plants of maize on six localities in western Slovakia, in the years 2008-2010 a 2014-2015. The aim of the study was to identify exact time of the emergence of the WCR adults in the consequence of different years and different localities and to find the best date for their eradication. The most of the WCR individuals at the northern locality were observed on 29 June and the first adults were found on 07 June, during colder year 2006. The development started about nine days earlier in the next year in southern Slovakia, because of extremely hot weather. The population of pest increased slower in 2008 than in previous years, and the highest appearance was monitored up-to 02 July. The first adults were monitored on 27 June in the years 2009-2010 as well as 2014-2015. Generally, the highest numbers of the first instar larvae were observed on 22 June at the locality Čiližská Radvaň. The second instar larvae and the most of adults was found on 20 June in Sokolce. On 29 June it was monitored the largest amount of the third instar larvae at the locality Čiližská Radvaň. The differences in the time of the emergence of adults depended on the year. Based on the monitoring in Slovakia, it can be expected the third instar larvae from second decade of June and the first adults in the last decade of June and in the first decade of July.

  6. CONTROL OF WESTERN CORN ROOTWORM (Diabrotica virgifera virgifera LeConte IN CORN PRODUCTION OF EASTERN CROATIA

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    Dražen Džoić

    2003-12-01

    Full Text Available A new insect pest - the western corn rootworm (Diabrotica virgifera virgifera LeConte was identified in Croatia in 1995. The first objective of this research was to determine the population density of all stages, except eggs in commercial cor fields. The second objective was to investigate the efficacy of three organophosphate insecticides on larvae. The experiment was conducted in Gunja, Croatia in 1999 and 2000. Treatments were commercial corn hybrids (OSSK 444, OSSK 552, Florencia, and three soil insecticides (terbuphos, chlorpyriphos-ethyl, chlormephos applied at planting. Results showed the highest number of larvae per plant (0.70 in the untreated plot of OSSK 552. In 1999, significant differences in larval numbers occurred among hybrids, but not among the insecticides. In 2000, larval numbers only differed statistically between the insecticide treatments. The highest beetles population counted per plant was 0.55 in 2000. This population level is very close to economic threshold of 0.70 beetles per plant. Significant differences in beetle numbers per plant between hybrids were only detected in 2000. Pheromone traps containing the lure, Csal♀m♂N, caught significantly more beetles than the Multigard yellow sticky-trap. Terbufos was the only soil insecticide providing a significant yield advantage to the hybrids. Based on the current value of corn and cost of insecticide, terbufos is the only soil insecticide cost-effective for growers. These studies should be conducted with other insecticides, and growers should avoid planting corn after corn in their fields.

  7. PROTECTION AGAINST WESTERN CORN ROOTWORM ADULTS (DIABROTICA VIRGIFERA VIRGIFERA LECONTE IN BARANYA COUNTY (HUNGARY

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    Veronika TÓTH

    2006-05-01

    Full Text Available With the settle of western corn rootworm (Diabrotica virgifera virgifera LeConte (from 1995, the spectrum of pests with potential damage in Hungary increased. The pest was followed by trapping (with sex-pheromone and colour traps. In 2000 the pest was found in whole Hungary (except Győr-Moson-Sopron, Vas and Szabolcs-Szatmár-Bereg county, in extremely fl uctuating number (1-700 pest/trap. In the southern region for maize production (Csongrád, Békés, Bács-Kiskun, Baranya, Tolna county, where the pest was found fi rst, the number of it increased in various centres. Based on these data, we carried out insecticide experiment.

  8. THE RESULTS OF INVESTIGATIONS OF WCR (Diabrotica virgifera virgifera Le Conte ATTACK ON THE AREA OF GUNJA IN 1999

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    Marija Ivezić

    2000-12-01

    Full Text Available Western Corn Rootworm (WCR (Diabrotica virgifera virgifera Le Conte is very important corn pest. The pest was spread in Croatia from 1995 to 1999 on 12,750 km2 . In the area of Stara Gunja, hybrid OSSK 444 was sown in order to investigate the possibilities of controls WCR with below ground insecticides - Counter G-5, Dursban G-7,5 and Dotan G-5. With checking root for larvae and cocoons 0.02 larvae was estimated on treated plots and 0.05 larvae on untreated plots. The number of cocoons was 0.12 in treated, and 0.25 on untreated plots. The number of imagoes on silk was 0.05–0.10 per plant. The imagoes of the WCR were caught with Pheromone and Multigard traps from the third decade of June until the first decade of October. On the traps settled on the treated plot (336 m2 , 1,376 imagoes were caught, compared to untreated plot (112 m2 where 431 imagoes were caught. The yield of corn was 8.03 t/ha in treatment with Dotan, 8.44 t/ha in treatment with Dursban, and 8.72 t/ha in treatment with Counter, while the lowest 7.98 t/ha was in control plot was. Low number of caught imagoes per plant, shows that, for now, the implementation of chemical preparations wasn’t justified. This kind of investigations should be continuing in the future, and the checking of corn roots must be done earlier in order to determine correct number of larvae on roots and the root damages.

  9. Impact of Cry3Bb1-expressing Bt maize on adults of the western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae).

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    Meissle, Michael; Hellmich, Richard L; Romeis, Jörg

    2011-07-01

    Genetically engineered maize producing insecticidal Cry3Bb1 protein from Bacillus thuringiensis (Bt) is protected from root damage by corn rootworm larvae. An examination was made to establish whether western corn rootworm (Diabrotica virgifera virgifera) adults are affected by Cry3Bb1-expressing maize (MON88017) when feeding on above-ground tissue. In laboratory bioassays, adult D. v. virgifera were fed for 7 weeks with silk, leaves or pollen from Bt maize or the corresponding near-isoline. Male, but not female, survival was reduced in the Bt-leaf treatment compared with the control. Female weight was lower when fed Bt maize, and egg production was reduced in the Bt-silk treatment. ELISA measurements demonstrated that beetles feeding on silk were exposed to higher Cry3Bb1 concentrations than beetles collected from Bt-maize fields in the United States. In contrast to silk and pollen, feeding on leaves resulted in high mortality and low fecundity. Females feeding on pollen produced more eggs than on silk. C:N ratios indicated that silk does not provide enough nitrogen for optimal egg production. Direct effects of Cry3Bb1 on adult beetles could explain the observed effects, but varietal differences between Bt and control maize are also possible. The impact of Bt maize on adult populations, however, is likely to be limited. Copyright © 2011 Society of Chemical Industry.

  10. Maize germplasm of eastern Croatia with native resistance to western corn rootworm (Diabrotica virgifera virgifera LeConte

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    Brkić Andrija

    2017-01-01

    Full Text Available The western corn rootworm (Diabrotica virgifera virgifera LeConte; WCR is a serious maize pest in Croatia. The species was first registered in Europe in the early 1990s and since then became one of the most dangerous maize pests, especially in parts of Central and Southeast Europe. Larvae that feed on the maize roots cause the most serious damages in maize fields. Management of this pest is difficult and expensive, with possible serious impact on the environment. Native (or host-plant resistance of maize against WCR could provide new economically and ecologically sustainable options in WCR management. Main goal of this study was to assess the variability of maize germplasm, correlations among resistance traits, and detect potential sources of resistance that could be used in breeding programs in order to develop hybrids with higher level of resistance against WCR. To our knowledge, the first native resistant hybrid is yet to be registered. Results showed great variability of estimated germplasm. Effect of the genotype was significant in all environments, as well as many interactions between genotype and the environment. Significant interactions emphasize the importance of the environment in WCR native resistance research. Significant positive correlations among all traits were detected. Several inbred lines were selected as a potentially useful germplasm for resistance breeding programs.

  11. On the influence of different host plants and of insecticide treatments on the population development of the western corn rootworm Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae

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    Fora, Ciprian George

    2014-02-01

    Full Text Available D. virgifera virgifera is classified as a quarantine pest in Germany, therefore the trials, presented in this paper, were performed in the western part of Romania, where the pest is well established since more than ten years. The field tests were carried out in close collaboration with Banat’s University of Agricultural Sciences and Veterinary Medicine, Timişoara. On sites highly infested by D. virgifera virgifera, 1 m² plots in four replications per variable were planted with maize for the chemical treatments and alternative crops (cereals and weeds. Gauze covered hatch cages were used for weekly counts of the emerged adult Diabrotica during the hatch period from mid of June to mid of August. It could be asserted that matured cereals are no host-plants for the western corn rootworm. In four years of trials not even one adult beetle hatched in the related cages. Setaria viridis and Digitaria sanguinalis reduced the number of hatched imagines significantly, nevertheless some individuals survived. Therefore an effective herbicide management against grass weeds in maize is recommended to limit the chance of survival of the pest. Clothianidin and Tefluthrin are effective against D. virgifera virgifera. 20% to 100% efficiency was assessed in the trials, strongly depending on precipitation and soil moisture in time of application. The insecticides decreased the maize root injury caused by larvae of the western corn rootworm significantly.

  12. A Maize Inbred Exhibits Resistance Against Western Corn Rootwoorm, Diabrotica virgifera virgifera.

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    Castano-Duque, Lina; Loades, Kenneth W; Tooker, John F; Brown, Kathleen M; Paul Williams, W; Luthe, Dawn S

    2017-12-01

    Insect resistance against root herbivores like the western corn rootworm (WCR, Diabrotica virgifera virgifera) is not well understood in non-transgenic maize. We studied the responses of two American maize inbreds, Mp708 and Tx601, to WCR infestation using biomechanical, molecular, biochemical analyses, and laser ablation tomography. Previous studies performed on several inbreds indicated that these two maize genotypes differed in resistance to pests including fall armyworm (Spodoptera frugiperda) and WCR. Our data confirmed that Mp708 shows resistance against WCR, and demonstrates that the resistance mechanism is based in a multi-trait phenotype that includes increased resistance to cutting in nodal roots, stable root growth during insect infestation, constitutive and induced expression of known herbivore-defense genes, including ribosomal inhibitor protein 2 (rip2), terpene synthase 23 (tps23) and maize insect resistance cysteine protease-1 (mir1), as well high constitutive levels of jasmonic acid and production of (E)-β-caryophyllene. In contrast, Tx601 is susceptible to WCR. These findings will facilitate the use of Mp708 as a model to explore the wide variety of mechanisms and traits involved in plant defense responses and resistance to herbivory by insects with several different feeding habits.

  13. Characterizing the mechanism of action of double-stranded RNA activity against western corn rootworm (Diabrotica virgifera virgifera LeConte.

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    Renata Bolognesi

    Full Text Available RNA interference (RNAi has previously been shown to be effective in western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte larvae via oral delivery of synthetic double-stranded RNA (dsRNA in an artificial diet bioassay, as well as by ingestion of transgenic corn plant tissues engineered to express dsRNA. Although the RNAi machinery components appear to be conserved in Coleopteran insects, the key steps in this process have not been reported for WCR. Here we characterized the sequence of events that result in mortality after ingestion of a dsRNA designed against WCR larvae. We selected the Snf7 ortholog (DvSnf7 as the target mRNA, which encodes an essential protein involved in intracellular trafficking. Our results showed that dsRNAs greater than or equal to approximately 60 base-pairs (bp are required for biological activity in artificial diet bioassays. Additionally, 240 bp dsRNAs containing a single 21 bp match to the target sequence were also efficacious, whereas 21 bp short interfering (si RNAs matching the target sequence were not. This result was further investigated in WCR midgut tissues: uptake of 240 bp dsRNA was evident in WCR midgut cells while a 21 bp siRNA was not, supporting the size-activity relationship established in diet bioassays. DvSnf7 suppression was observed in a time-dependent manner with suppression at the mRNA level preceding suppression at the protein level when a 240 bp dsRNA was fed to WCR larvae. DvSnf7 suppression was shown to spread to tissues beyond the midgut within 24 h after dsRNA ingestion. These events (dsRNA uptake, target mRNA and protein suppression, systemic spreading, growth inhibition and eventual mortality comprise the overall mechanism of action by which DvSnf7 dsRNA affects WCR via oral delivery and provides insights as to how targeted dsRNAs in general are active against insects.

  14. Histopathological Effects of Bt and TcdA Insecticidal Proteins on the Midgut Epithelium of Western Corn Rootworm Larvae (Diabrotica virgifera virgifera

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    Andrew J. Bowling

    2017-05-01

    Full Text Available Western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte is a major corn pest in the United States, causing annual losses of over $1 billion. One approach to protect against crop loss by this insect is the use of transgenic corn hybrids expressing one or more crystal (Cry proteins derived from Bacillus thuringiensis. Cry34Ab1 and Cry35Ab1 together comprise a binary insecticidal toxin with specific activity against WCR. These proteins have been developed as insect resistance traits in commercialized corn hybrids resistant to WCR feeding damage. Cry34/35Ab1 is a pore forming toxin, but the specific effects of Cry34/35Ab1 on WCR cells and tissues have not been well characterized microscopically, and the overall histopathology is poorly understood. Using high-resolution resin-based histopathology methods, the effects of Cry34/35Ab1 as well as Cry3Aa1, Cry6Aa1, and the Photorhabdus toxin complex protein TcdA have been directly visualized and documented. Clear symptoms of intoxication were observed for all insecticidal proteins tested, including swelling and sloughing of enterocytes, constriction of midgut circular muscles, stem cell activation, and obstruction of the midgut lumen. These data demonstrate the effects of these insecticidal proteins on WCR midgut cells, and the collective response of the midgut to intoxication. Taken together, these results advance our understanding of the insect cell biology and pathology of these insecticidal proteins, which should further the field of insect resistance traits and corn rootworm management.

  15. Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte) Populations in Western Nebraska and Kansas.

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    Pereira, Adriano E; Wang, Haichuan; Zukoff, Sarah N; Meinke, Lance J; French, B Wade; Siegfried, Blair D

    2015-01-01

    Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99) was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial). For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99) were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed.

  16. Evidence of Field-Evolved Resistance to Bifenthrin in Western Corn Rootworm (Diabrotica virgifera virgifera LeConte Populations in Western Nebraska and Kansas.

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    Adriano E Pereira

    Full Text Available Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99 was determined and used to test adults of both laboratory and field populations. Larval susceptibility was also tested using both laboratory and field populations. Significant differences were recorded in adult and larval susceptibility among WCR field and laboratory populations. The highest LC50 for WCR adults was observed in populations from Keith 2 and Chase Counties, NE, with LC50s of 2.2 and 1.38 μg/vial, respectively, and Finney County 1, KS, with 1.43 μg/vial, as compared to a laboratory non-diapause population (0.24 μg/vial. For larvae, significant differences between WCR field and laboratory populations were also recorded. Significant differences in mortalities at the diagnostic bifenthrin concentration (LC99 were observed among WCR adult populations with western Corn Belt populations exhibiting lower susceptibility to bifenthrin, especially in southwestern Nebraska and southwestern Kansas. This study provides evidence that resistance to bifenthrin is evolving in field populations that have been exposed for multiple years to pyrethroid insecticides. Implications to sustainable rootworm management are discussed.

  17. Field efficacy of Heterorhabditis bacteriophora (Nematoda: Heterorhabditidae), Metarhizium brunneum (Hypocreales: Clavicipitaceae), and chemical insecticide combinations for Diabrotica virgifera virgifera larval management

    DEFF Research Database (Denmark)

    Rauch, Hannes; Steinwender, Bernhardt Michael; Mayerhofer, Johanna

    2017-01-01

    A two-year field study using a blend of entomopathogens in conjunction with chemical insecticides was carried out to determine to which extent they affect western corn rootworm (WCR), Diabrotica virgifera virgifera, survival, maize root damages, and grain yield and to assess the potential for sid...... is considerably higher than the stipulated economic threshold under favourable growing conditions, but a systematic crop rotation is recommended as an integral part of the WCR management both as a prophylaxis and as a background for the best treatment....

  18. EFFECT OF DIFFERENT TRAPS ON CAPTURES OF ADULT CORN ROOTWORM BEETLES (Diabrotica virgifera virgifera LeConte IN EAST SLAVONIA

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    Marija Ivezić

    2002-12-01

    Full Text Available In 1995 the corn rootworm (Diabrotica virgifera virgifera LeConte was detected for the first time in east Slavonia, Croatia. Its expansion to the west part has been very fast and from year to year populations of the pest are higher, especially when corn is planted after corn. The aim of this investigation was to find the best trap for monitoring Diabrotica. The studies were conducted by using three types of traps: the USA Trece lure trap, Multigard yellow sticky trap and Hungarian pheromone trap. The treatments were replicated four times in a maize field located in the east of Croatia, very near to the Yugoslavia border. The traps were placed in the field on the 23rd of June and the experiment continued until the 15th of September. Pheromone and Multigard sticky traps were replaced with new ones each month. Traps were positioned 60 m apart within a row and 70 m apart across maize rows. Silking occurred from 30 June to 8 August (exposed silk thoroughly brown and dry. This year was extremely dry, and the first beetles were noticed on the 15th of June. It was 20 days earlier than in 1999. Adult rootworm beetles were removed from the traps once weekly. Pheromone traps captured the most beetles (2263, Multigard sticky traps caught the second most (214 and lure traps the fewest (182 for the whole period. After the replacement of pheromone and Multigard traps, the capture of beetles increased. Of the total number of beetles caught, 85.10% was caught by the pheromone traps, 8.05% by the Multigard sticky traps and 6.85% by the lure traps. Due to this year’s dryness (50% less rainfall than the 20 year average, the investigation should be continued in the future to get more precise results.

  19. Secondary Contact and Admixture between Independently Invading Populations of the Western Corn Rootworm, Diabrotica virgifera virgifera in Europe

    Science.gov (United States)

    Bermond, Gérald; Ciosi, Marc; Lombaert, Eric; Blin, Aurélie; Boriani, Marco; Furlan, Lorenzo; Toepfer, Stefan; Guillemaud, Thomas

    2012-01-01

    The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i) genetic variation is greater in the contact zone than in the parental outbreaks; ii) several signs of admixture were detected in some Venetian samples, in a Bayesian analysis of the population structure and in an approximate Bayesian computation analysis of historical scenarios and, finally, iii) allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed. PMID:23189184

  20. Monitoring Diabrotica v. virgifera (Col.: Chrysomelidae) in southeastern Slovenia: increasing population trend and host spectrum expansion.

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    Ulrichs, C; Dinnesen, S; Nedelev, T; Hummel, H E; Modic, S; Urek, G

    2008-01-01

    Ever since the western corn rootworm (WCR) (Diabrotica virgifera virgifera), an alien invasive species from North America, has been introduced into Europe on at least 3 separate occasions, it spread within 15 years over the entire area of south-eastern and central Europe (except Denmark). Until quite recently, Zea mays L. was the only known host plant whereas in North America WCR also attacks members of the plant family Cucurbitaceae. In August of 2006, we were able to validate these findings also in the Old World by observing WCR visiting blossoms of oil pumpkin (Cucurbita pepo L.). Beside this first report of WCR on this regionally and economically important crop, a population increase in Gaberje near Lendava, Eastern Slovenia, was observed. Some future consequences of multiple hosts for integrated pest management (IPM) of WCR are being discussed.

  1. The importance of the western corn rootworm (Diabrotica virgifera virgifera LeConte in Bavaria – local relevance and economic impact on single farms

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    Köhler, Katrin

    2014-02-01

    Full Text Available The western corn rootworm (Diabrotica virgifera virgifera LeConte, holding a quarantine status in the European Union, was first discovered in 2007 in southern Bavaria. In the course of Diabrotica Research Program of Germany and the states of Bavaria and Baden-Württemberg, an economic accompanying research is conducted at single farm level in Bavaria. This aims to evaluate different adaptation measures concerning the eradication and containment strategies economically. The focus of the analysis is mainly the crop rotation and the reduction of the proportion of maize at farm level. InVeKoS-data are analyzed, in order to assess the economic relevance of the pest in Bavaria in a better way. These enable detailed information on the development of maize production and cropping intensity. Subsequently research regions are defined with a high maize density, expecting enhanced damage from the beetle. In these selected areas single farms are selected. For considerations on single farm level, farms with different farm types are chosen by which adaptation measures are evaluated and realistic impact assessment could be made. For the evaluation of the economic impacts a whole-farm simulation has been used to include indirect effects of different adoption strategies. Additional, semi-structured interviews were conducted at selected farms in order to prove the results of the case study, obtain more information about the consequences on farm level and to evaluate the proposed cultivation alternatives for maize. A benefit-cost analysis and the comparative analysis of possible damage caused by the beetle and cost adjustments complete the study.

  2. Characterisation of cysteine proteinases responsible for digestive proteolysis in guts of larval Western corn rootworm (Diabrotica virgifera) by expression in the yeast Pichia pastoris

    NARCIS (Netherlands)

    Bown, D.P.; Wilkinson, H.S.; Jongsma, M.A.; Gatehouse, J.A.

    2004-01-01

    Cysteine proteinases are the major class of enzymes responsible for digestive proteolysis in western corn rootworm (Diabrotica virgifera), a serious pest of maize. A larval gut extract hydrolysed typical cathepsin substrates, such as Z-phe-arg-AMC and Z-arg-arg-AMC, and hydrolysis was inhibited by

  3. Distribution of MCA-coated grits in maize fields after high wheel tractor application for disrupting orientation of Diabrotica virgifera virgifera LeConte.

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    Wennemann, Ludger; Hummel, Hans E

    2002-01-01

    High wheel tractor applications of 4-methoxycinnamaldehyde (MCA)-coated corn granules ('grits') were conducted in Ruski Krstur (Serbia) in summer 2001 in a 5 ha corn field. Grits are a by-product after corn is harvested and separated from the cob and used as a carrier medium to disseminate MCA into the corn field. MCA is a kairomone mimic derived form Cucurbita maxima (Duchesne) used to disrupt orientation of Diabrotica virgifera virgifera LeConte towards different MCA and pheromone baited traps. The ultimate goal is to investigate the use of MCA as a mating disruptant. MCA was dissolved in an organic solvent and mixed in a cement machine with the grits. Grits were applied at rates of 17.39, 17.1 and 12.45 kg/ha on July 4th, July 19th and August 3rd. Before the impact of MCA as a disruptant can be addressed, the distribution patterns of MCA coated grits have to be thoroughly investigated. They were evaluated by counting girts deposited in 16 or 20 plastic dishes of 30-cm diameter positioned along 2 rows through the field directly after the grit application by tractor. Additionally, grits deposited on corn plant surface such as leaves, leaf axils and corn cobs were counted. Total number of grits collected in plastic dishes revealed even application rates at the first and second application but not on the third application date. Number of grits collected on plant surfaces were significantly different from each other regarding each application date. Altogether, grit distribution in the dishes as well as on the plant surface was variable. However, distribution patterns achieved so far hold promise to disseminate MCA coated grits into corn fields for orientation disruption or mating disruption of D. virgifera virgifera.

  4. Containment of the western corn rootworm Diabrotica v.virgifera: continued successful management 2008 in southern Switzerland by monitoring and crop rotation.

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    Hummel, Hans E; Bertossa, M

    2009-01-01

    Diabrotica virgifera virgifera LeConte (Col.: Chrysomelidae), known as western corn rootworm (WCR) and endemic in North America, invaded Europe about two decades ago. Various unsuccessful attempts have been made to eradicate it from the Old World. Management with a variety of strategies is the option now remaining. WCR management in Southern Switzerland by a unique containment approach has been practiced successfully since 2003 using biotechnical means. Without any chemical pesticides or GMO input, the Swiss government mandated adherence to strict crop rotation. In addition to the economic benefits of this relatively simple approach, the environment was saved a considerable burden of pesticide applications. Other countries are invited to follow this example of sustainable pest management.

  5. Orientation disruption of Diabrotica virgifera virgifera in maize by a liquid MCA formulation released from paper squares in the Banat region of Serbia and Montenegro.

    Science.gov (United States)

    Hummel, H E; Baca, F I; Erski, P

    2003-01-01

    Serbia-Montenegro, formerly the Republic of Yugoslavia, is the first European Country where Diabrotica virgifera virgifera Le Conte (Col.: Chrysomelidae) (D.v.v.) was reported in 1992 as an invasive alien pest species, Baca (1993), Camprag and Baca, (1995): From a focal point near Belgrade airport, the maize pest quickly spread in all directions reaching the economic threshold in a number of surrounding countries around 1995. The field experiments described took place in the Banat region east of Belgrade in July of 2002. The plant kairomone mimic 4-methoxycinnamaldehyde (MCA) dissolved in acetone was slowly volatilized from paper squares. It permeated a maize field of known D.v.v. history of 0.5 ha size 3 km north of the village of Crepaja. With release rates of 266 g/ha, max. orientation disruption levels of 55% were achieved. The total amount of MCA was distributed in two manual applications. Readings of orientation levels were continued for eleven days during the latter part of July and into early August of 2002.

  6. Time of planting and choice of maize hybrids in controlling WCR (Diabrotica virgifera virgifera Le Conte) in Serbia and Montenegro.

    Science.gov (United States)

    Baca, F; Videnovic, Z; Erski, P; Stankovic, R; Dobrikovic, Danica

    2003-01-01

    increased from 16.0 to 63.9%. To successfully decrease the size and intensity of attacks of the Diabrotica v. virgifera population under conditions of applying insecticides or not, it is necessary to use maize hybrids of the earliest possible maturity group and to plant the seed on the earliest date possible in the first year of growing maize, if maize is to be followed by maize in the next year.

  7. Successful application of entomopathogenic nematodes for the biological control of western corn rootworm larvae in Europe – a mini review

    Directory of Open Access Journals (Sweden)

    Toepfer, Stefan

    2014-02-01

    Full Text Available 10 years of joint efforts in research and development have led to a nematode-based biological control solution for one of the most destructive maize pests, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae. Commercially mass-produced Heterorhabditis species of beneficial entomopathogenic nematodes are ready to use. They can be applied into the soil during sowing of maize for controlling the subsequently hatching larvae of D. virgifera virgifera thus preventing root feeding and damage to maize. Policy bodies, decision makers and farmers are advised to consider biological control as one of the alternatives to synthetic pesticides in maize production, and according to the EC Directive on the sustainable use of pesticides and implementation of integrated pest management.

  8. A promising biotechnical approach to pest management of Diabrotica virgifera virgifera in Illinois maize fields under kairomonal shielding with the new MSD technique.

    Science.gov (United States)

    Hummel, H E; Shaw, J T; Hein, D F

    2005-01-01

    Environmentally compatible and sustainable plant protection requires novel approaches to pest management characterized by minimal emphasis on toxicants. Classical toxicants traditionally dominated economic entomology for half a century. But worldwide problems with environmental pollution and with increasing resistance levels in all major pesticide classes and in many key insect species including Diabrotica virgifera virgifera (D.v.v.) strongly advocate a rethinking and a change in management paradigms used. Soft, minimally invasive, biological, biotechnical and cultural approaches should replace hard pesticides which are in favor up to now. Fortunately, pheromones, kairomones, plant attractants, better traps, new plant varieties and cultural methods like crop rotation, in short more sophisticated methods are now available as pressure for finding and exploring novel strategies increases. Facing this situation, a new biotechnical approach of population reduction of D.v.v., called "MSD" technique, is introduced. MSD is characterized as an approach combining mass trapping, shielding and deflecting of adult insects along an invisible odor barrier of synthetic kairomone which diminishes the flux of insects across a high capacity trap line baited with kairomone, thus reducing both the population fluctuation and number and its reproductive success within the shielded area. In the case of D.v.v. in Zea mays fields, effects realized by the MSD technique have been measured simultaneously by a number of independent criteria during the summers of 2003 and 2004 at 2 different locations in Illinois maize fields of up to one half hectare size. Results observed are statistically significant and cannot be explained by mass trapping alone. There is also an additional shielding and deflection, in short "diversion" effect whose basic sensory and behavioral mechanisms call for future exploration.

  9. PREDICTING THE EMERGENCE OF CORN ROOTWORM (Diabrotica virgifera virgifera LeConte IN ESTERN SLAVONIA

    Directory of Open Access Journals (Sweden)

    Dražen Đoić

    2009-12-01

    Full Text Available Corn (Zea mays L. is one of the most important field crops in Croatia, country as well as in the world. It is subjected to many pests, among which is corn rootworm. Corn rootworms (Diabrotica virgifera virgifera LeConte are economically significant pests of corn, especially at successive growing of corn or single culture growing. In our corn fields, corn rootworm was a pest since its first appearance in 1995, and more significant damages were detected in 2002. The monitoring of the corn rootworm population enables the development of more efficient models for predicting adult corn rootworm emergence and the control of these pests. The objective of this thesis is to determine the influence of row spacing to corn rootworm population, larval root damages and grain yield. Then, to develop models to predict adult corn rootworm emergence in Eastern Slavonia, based on accumulated degree-days for air temperature, and to determine optimum time for monitoring and for possible control of adult cron rootworms based on ovarian development of the gravid females. The researches were conducted in 2004 and in 2005 in Gunja and Soljani, with two sowing models, row spacing of 50 cm and 70 cm. Hybrid corn OSSK 552 was sown in four repetitions at both sites. Cages and pheromone traps were placed in order to estimate the first day of corn rootworm emergence (the biofix and to monitor the total population number. Predicting of the adult corn rootworm emergence was based on degree–days for air temperature from the biofix. In mid–July, evaluation of the larval damage was made according to the scale from 0–3. Ovarian development was determined by dissection of the gravid females, whereas the complete female gravidity and optimum time for scouting were determined based on degree–days accumulated from the biofix. The larval population was not significantly increased at the reduced row spacing. The number of the larvae per a plant was 24% higher on the average at 50

  10. Dietary risk assessment of v-ATPase A dsRNAs on monarch butterfly larvae

    Science.gov (United States)

    The goal of this study is to assess the risks of RNA interference (RNAi)-based genetically engineered crops on a non-target arthropod, monarch butterfly, Danaus plexippus. We hypothesize that an insecticidal double-stranded (ds) RNA targeting western corn rootworm, Diabrotica virgifera virgifera, ha...

  11. Host Recognition Responses of Western (Family: Chrysomelidae) Corn Rootworm Larvae to RNA Interference and Bt Corn.

    Science.gov (United States)

    Zukoff, Sarah N; Zukoff, Anthony L

    2017-01-01

    Western corn rootworm Diabrotica virgifera virgifera LeConte is an important pest of corn whose larvae exhibit particular quantifiable patterns of locomotion after exposure to, and removal from, host roots and nonhost roots. Using EthoVision software, the behavior and locomotion of the western corn rootworm larvae was analyzed to determine the level of host recognition to germinated roots of differing corn hybrids containing either rootworm targeted Bt genes, RNA interference (RNAi) technology, the stack of both Bt and RNAi, or the isoline of these. The behavior of the rootworm larvae indicated a significant host preference response to all corn hybrids (with or without insecticidal traits) compared to the filter paper and oat roots. A weaker host response to the RNAi corn roots was observed in the susceptible larvae when compared to the resistant larvae, but not for the Bt + RNAi vector stack. Additionally, the resistant larvae demonstrated a weaker host response to the isoline corn roots when compared to the susceptible larvae. Although weaker, these host responses were significantly different from those observed in the negative controls, indicating that all hybrids tested do contain the contact cues necessary to elicit a host preference response by both Cry3Bb1-resistant and Cry3Bb1-susceptible larvae that would work to hinder resistance development in refuge in a bag fields. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  12. A new artificial diet for western corn rootworm larvae is compatible with and detects resistance to all current Bt toxins

    Science.gov (United States)

    Insect resistance to transgenic crops expressing one or more genes from Bacillus thuringiensis Berliner (Bt) is a growing concern for farmers, regulatory agencies, the seed industry, and researchers alike. Western corn rootworm (Diabrotica virgifera virgifera LeConte) is a pest of corn (Zea mays L.)...

  13. Introduction of Diabrotica virgifera virgifera into the Old World and its consequences: a recently acquired invasive alien pest species on Zea mays from North America.

    Science.gov (United States)

    Hummel, H E

    2003-01-01

    Diabrotica v. virgifera LeConte (Coleoptera: Chrysomelidae), (in short D.v.v.), with common name western corn rootworm, is endemic to the New World. Originating in the regions from South America to Mexico where it was in biological equilibrium with its natural enemies, predators and pathogens, it moved north with its food plants. Probably due to human agricultural farm practices with preference for monoculture of maize, the insect found open niches for expanding to the midwestern US where LeConte first described the species in Nebraska in 1867. Cyclodiene insecticide resistance, discovered in 1961, accelerated its spread and movement across the Great Plaines to the Atlantic Coast where it arrived around 1980. D.v.v. is a costly adversary to maize, to cucurbit, and, because of recent hostshifts, a threat to soybean production. Booming air travel and shipments of goods by air provided opportunities for D.v.v., without its natural enemies, to invade Europe where the insect was first described by F. Baca in 1993 near Belgrade airport (Baca 1993, Camprag & Baca 1995). From this focal point, D.v.v. expanded its range in all directions. Ten years later, in 2002, most of southeastern Europe has D.v.v. populations, some of them reaching economic damage levels such as those in Serbia, Croatia, and Hungary. New spot infestations in Northern Italy (Veneto, Lombardy, Piemonte) and in the Ticino region of Southern Switzerland, but also in Austria, Slovakia, Czechia, the Ukraine, even France, signal the final arrival of D.v.v. in Central Europe. The Alps, formerlyconsidered a natural barrier, might be circumvented or trespassed via air and road traffic. Model calculations by Baufeld and Enzian (2003) show that climatic and survival conditions are favorable for D.v.v. in all of Central Europe. Yet, in spite of well known annual losses of one billion dollars in the US, an effective and sustainable European strategy for keeping D.v.v. in check is still missing.

  14. Soil application of an encapsulated CO2 source and its potential for management of western corn rootworm larvae.

    Science.gov (United States)

    Schumann, M; Patel, A; Vidal, S

    2014-02-01

    Western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae use carbon dioxide (CO2) to locate the roots of their hosts. This study investigated whether an encapsulated CO2 source (CO2-emitting capsules) is able to outcompete CO2 gradients established by corn root respiration in the soil. Furthermore, the following two management options with the capsules were tested in semifield experiments (0.5- to 1-m2 greenhouse plots): the disruption of host location and an "attract-and-kill" strategy in which larvae were lured to a soil insecticide (Tefluthrin) between the corn rows. The attract-and-kill strategy was compared with an application of Tefluthrin in the corn rows (conventional treatment) at 33 and 18% of the standard field application rate. Application of the CO2-emitting capsules 30 cm from the plant base increased CO2 levels near the application point for up to 20 d with a peak at day 10. Both the disruption of host location and an attract-and-kill strategy caused a slight but nonsignificant reduction in larval densities. The disruption of host location caused a 17% reduction in larval densities, whereas an attract-and-kill strategy with Tefluthrin added at 33 and 18% of the standard application rate caused a 24 and 27% reduction in larval densities, respectively. As presently formulated, the CO2-emitting capsules, either with or without insecticide, do not provide adequate control of western corn rootworm.

  15. Oviposition Behaviors in Relation to Rotation Resistance in the Western Corn Rootworm

    NARCIS (Netherlands)

    Knolhoff, L.M.; Glas, J.J.; Spencer, J.L.; Berenbaum, M.R.

    2010-01-01

    Across a large area of the midwestern United States Corn Belt, the western corn rootworm beetle (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) exhibits behavioral resistance to annual crop rotation. Resistant females exhibit increased locomotor activity and frequently lay eggs

  16. Direct and indirect plant defenses are not suppressed by endosymbionts of a specialist root herbivore

    Science.gov (United States)

    Insect endosymbionts influence many important metabolic and developmental processes of their host. It has been speculated that they may also help to manipulate and suppress plant defenses to the benefit of herbivores. Recently, endosymbionts of the root herbivore Diabrotica virgifera virgifera have ...

  17. Vliv pěstování GM kukuřice na vybrané necílové druhy členovců

    Czech Academy of Sciences Publication Activity Database

    Skoková Habuštová, Oxana; Svobodová, Zdeňka

    2012-01-01

    Roč. 60, č. 9 (2012), s. 29-32 ISSN 0139-6013 R&D Projects: GA MZe QH91093 Grant - others:GA JU(CZ) 04-062/2011/P Institutional research plan: CEZ:AV0Z50070508 Keywords : Diabrotica virgifera virgifera Subject RIV: EH - Ecology, Behaviour

  18. Quantitative trait loci mapping of western corn rootworm (Coleoptera: Chrysomelidae) host plant resistance in two populations of doubled haploid lines in maize (Zea mays L.)

    Science.gov (United States)

    Over the last 70 years, more than 12,000 maize accessions have been screened for their level of resistance to western corn rootworm, Diabrotica virgifera virgifera LeConte, larval feeding. Less than 1% of this germplasm was selected for initiating recurrent selection or other breeding programs. Sele...

  19. Heterorhabditis sp. (Nematoda: Heterorhabditidae): A Nematode Parasite Isolated from the Banded Cucumber Beetle Diabrotica balteata

    Science.gov (United States)

    Creighton, C. S.; Fassuliotis, G.

    1985-01-01

    A nematode identified as Heterorhabditis sp. was discovered in June 1982 in larval cadavers of the banded cucumber beetle, Diabrotica balteata, in soil on wooded land. Effective beetle control (over 95%) was obtained when larvae were exposed to potted soil containing infective stage nematode juveniles or infected larval cadavers. The nematode was propagated in vivo on larvae of D. balteata, Diaphania nitidalis (the pickleworm), and Galleria mellonella (the greater wax moth). This Heterorhabditis sp. has promising potential as a biocontrol agent for the banded cucumber beetle. PMID:19294074

  20. Effectiveness of corn rootworm (Coleoptera: Chrysomelidae) areawide pest management in South Dakota.

    Science.gov (United States)

    French, B Wade; Chandler, Laurence D; Riedell, Walter E

    2007-10-01

    Diabrotica barberi Smith & Lawrence and Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) are serious pests of maize, Zea mays L. To reduce the amount of toxicants released into the environment, the Agricultural Research Service implemented a 5-yr (1997-2001) areawide pest management program in five geographic locations, including one in South Dakota. The objective was to use integrated pest management tactics to suppress adult Diabrotica populations over a broad geographic area by using aerially applied semiochemical-baited insecticides. Suppressed populations theoretically should reduce oviposition, limit larval feeding damage to maize roots, and result in fewer beetles emerging in subsequent years. We used emergence cages, sticky traps, and CRW lure traps to monitor adult D. barberi and D. v. virgifera populations. We sampled for Diabrotica eggs, and we determined damage to maize roots. We sampled in several maize fields (control) located near the areawide site. The baited insecticides were effective in reducing adult populations 1 and 2 wk after application, and most remained low for the duration of the maize growing season. Fewer beetles were captured in both sticky and lure traps in the areawide site than in the control site. With a few exceptions, egg counts, adult emergence, and maize root damage were similar between the areawide and control sites; however, maize roots had greater fresh weight in the control site. Although not all goals were accomplished, when considering the amount of toxicant released into the environment, using semiochemical-baited insecticides to suppress adult pest Diabrotica populations seems to be an effective areawide management tool.

  1. Assessment of Inheritance and Fitness Costs Associated with Field-Evolved Resistance to Cry3Bb1 Maize by Western Corn Rootworm.

    Science.gov (United States)

    Paolino, Aubrey R; Gassmann, Aaron J

    2017-05-11

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is among the most serious insect pests of maize in North America. One strategy used to manage this pest is transgenic maize that produces one or more crystalline (Cry) toxins derived from the bacterium Bacillus thuringiensis (Bt). To delay Bt resistance by insect pests, refuges of non-Bt maize are grown in conjunction with Bt maize. Two factors influencing the success of the refuge strategy to delay resistance are the inheritance of resistance and fitness costs, with greater delays in resistance expected when inheritance of resistance is recessive and fitness costs are present. We measured inheritance and fitness costs of resistance for two strains of western corn rootworm with field-evolved resistance to Cry3Bb1 maize. Plant-based and diet-based bioassays revealed that the inheritance of resistance was non-recessive. In a greenhouse experiment, in which larvae were reared on whole maize plants in field soil, no fitness costs of resistance were detected. In a laboratory experiment, in which larvae experienced intraspecific and interspecific competition for food, a fitness cost of delayed larval development was identified, however, no other fitness costs were found. These findings of non-recessive inheritance of resistance and minimal fitness costs, highlight the potential for the rapid evolution of resistance to Cry3Bb1 maize by western corn rootworm, and may help to improve resistance management strategies for this pest.

  2. Assessment of Inheritance and Fitness Costs Associated with Field-Evolved Resistance to Cry3Bb1 Maize by Western Corn Rootworm

    Directory of Open Access Journals (Sweden)

    Aubrey R. Paolino

    2017-05-01

    Full Text Available The western corn rootworm, Diabrotica virgifera virgifera LeConte, is among the most serious insect pests of maize in North America. One strategy used to manage this pest is transgenic maize that produces one or more crystalline (Cry toxins derived from the bacterium Bacillus thuringiensis (Bt. To delay Bt resistance by insect pests, refuges of non-Bt maize are grown in conjunction with Bt maize. Two factors influencing the success of the refuge strategy to delay resistance are the inheritance of resistance and fitness costs, with greater delays in resistance expected when inheritance of resistance is recessive and fitness costs are present. We measured inheritance and fitness costs of resistance for two strains of western corn rootworm with field-evolved resistance to Cry3Bb1 maize. Plant-based and diet-based bioassays revealed that the inheritance of resistance was non-recessive. In a greenhouse experiment, in which larvae were reared on whole maize plants in field soil, no fitness costs of resistance were detected. In a laboratory experiment, in which larvae experienced intraspecific and interspecific competition for food, a fitness cost of delayed larval development was identified, however, no other fitness costs were found. These findings of non-recessive inheritance of resistance and minimal fitness costs, highlight the potential for the rapid evolution of resistance to Cry3Bb1 maize by western corn rootworm, and may help to improve resistance management strategies for this pest.

  3. New species of Diabrotica Chevrolat (Coleoptera: Chrysomelidae: Galerucinae and a key to Diabrotica and related genera: results of a synopsis of North and Central American Diabrotica species

    Directory of Open Access Journals (Sweden)

    Alexander Derunkov

    2015-02-01

    Full Text Available The following 18 new species of Diabrotica are described and illustrated as a result of the synopsis of North and Central American species: D. barclayi sp. nov., Guatemala; D. caveyi sp. nov., Costa Rica; D. costaricensis sp. nov., Costa Rica; D. dmitryogloblini sp. nov., Mexico; D. duckworthorum sp. nov., Honduras; D. hartjei sp. nov., Panama; D. josephbalyi sp. nov., Costa Rica; D. lawrencei sp. nov., Mexico; D. mantillerii sp. nov., Panama; D. martinjacobyi sp. nov., Honduras; D. mitteri sp. nov., Panama; D. perkinsi sp. nov., Guatemala; D. redfordae sp. nov., Costa Rica; D. reysmithi sp. nov., Costa Rica; D. salvadorensis sp. nov., El Salvador; D. sel sp. nov., Panama; D. spangleri sp. nov., Costa Rica; D. waltersi sp. nov., Panama. In addition, a key to separate Diabrotica from related genera is presented.

  4. Germline transformation of the western corn rootworm, Diabrotica virgifera virgifera.

    Science.gov (United States)

    Chu, F; Klobasa, W; Wu, P; Pinzi, S; Grubbs, N; Gorski, S; Cardoza, Y; Lorenzen, M D

    2017-08-01

    The western corn rootworm (WCR), a major pest of maize, is notorious for rapidly adapting biochemically, behaviourally and developmentally to a variety of control methods. Despite much effort, the genetic basis of WCR adaptation remains a mystery. Since transformation-based applications such as transposon tagging and enhancer trapping have facilitated genetic dissection of model species such as Drosophila melanogaster, we developed a germline-transformation system for WCR in an effort to gain a greater understanding of the basic biology of this economically important insect. Here we report the use of a fluorescent-marked Minos element to create transgenic WCR. We demonstrate that the transgenic strains express both an eye-specific fluorescent marker and piggyBac transposase. We identified insertion-site junction sequences via inverse PCR and assessed insertion copy number using digital droplet PCR (ddPCR). Interestingly, most WCR identified as transgenic via visual screening for DsRed fluorescence proved to carry multiple Minos insertions when tested via ddPCR. A total of eight unique insertion strains were created by outcrossing the initial transgenic strains to nontransgenic WCR mates. Establishing transgenic technologies for this beetle is the first step towards bringing a wide range of transformation-based tools to bear on understanding WCR biology. © 2017 The Royal Entomological Society.

  5. Assessment of potential risks of dietary RNAi to a soil micro-arthropod, Sinella curviseta Brook (Collembola: Entomobryidae

    Directory of Open Access Journals (Sweden)

    Huipeng Pan

    2016-07-01

    Full Text Available RNAi-based genetically engineered (GE crops for the management of insect pests are likely to be commercialized by the end of this decade. Without a workable framework for conducting the ecological risk assessment (ERA and a standardized ERA protocol, however, the utility of RNAi transgenic crops in pest management remains uncertain. The overall goal of this study is to assess the risks of RNAi-based GE crops on a non-target soil micro-arthropod, Sinella curviseta, which could be exposed to plant-protected dsRNAs deposited in crop residues. Based on the preliminary research, we hypothesized that insecticidal dsRNAs targeting at the western corn rootworm, Diabrotica virgifera virgifera, a billion-dollar insect pest, has no adverse impacts on S. curviseta, a soil decomposer. Following a tiered approach, we tested this risk hypothesis using a well-designed dietary RNAi toxicity assay. To create the worst-case scenario, the full-length cDNA of v-ATPase subunit A from S. curviseta were cloned and a 400 bp fragment representing the highest sequence similarity between target pest and non-target arthropods was selected as the template to synthesize insecticidal dsRNAs. Specifically, 10-day old S. curviseta larvae were subjected to artificial diets containing v-ATPase A dsRNAs from both D. v. virgifera (dsDVV and S. curviseta (dsSC, respectively, a dsRNA control, β-glucuronidase, from plant (dsGUS, and a vehicle control, H2O. The endpoint measurements included gene expression profiles, survival, and life history traits, such as developmental time, fecundity, hatching rate, and body length. Although S. curviseta larvae developed significantly faster under the treatments of dsDVV and dsSC than the vehicle control, the combined results from both temporal RNAi effect study and dietary RNAi toxicity assay support the risk hypothesis, suggesting that the impacts of ingested arthropod-active dsRNAs on this representative soil decomposer are negligible.

  6. Gene silencing in Tribolium castaneum as a tool for the targeted identification of candidate RNAi targets in crop pests.

    Science.gov (United States)

    Knorr, Eileen; Fishilevich, Elane; Tenbusch, Linda; Frey, Meghan L F; Rangasamy, Murugesan; Billion, Andre; Worden, Sarah E; Gandra, Premchand; Arora, Kanika; Lo, Wendy; Schulenberg, Greg; Valverde-Garcia, Pablo; Vilcinskas, Andreas; Narva, Kenneth E

    2018-02-01

    RNAi shows potential as an agricultural technology for insect control, yet, a relatively low number of robust lethal RNAi targets have been demonstrated to control insects of agricultural interest. In the current study, a selection of lethal RNAi target genes from the iBeetle (Tribolium castaneum) screen were used to demonstrate efficacy of orthologous targets in the economically important coleopteran pests Diabrotica virgifera virgifera and Meligethes aeneus. Transcript orthologs of 50 selected genes were analyzed in D. v. virgifera diet-based RNAi bioassays; 21 of these RNAi targets showed mortality and 36 showed growth inhibition. Low dose injection- and diet-based dsRNA assays in T. castaneum and D. v. virgifera, respectively, enabled the identification of the four highly potent RNAi target genes: Rop, dre4, ncm, and RpII140. Maize was genetically engineered to express dsRNA directed against these prioritized candidate target genes. T 0 plants expressing Rop, dre4, or RpII140 RNA hairpins showed protection from D. v. virgifera larval feeding damage. dsRNA targeting Rop, dre4, ncm, and RpII140 in M. aeneus also caused high levels of mortality both by injection and feeding. In summary, high throughput systems for model organisms can be successfully used to identify potent RNA targets for difficult-to-work with agricultural insect pests.

  7. RELATIONS AMONG WESTERN CORN ROOTWORM RESISTANCE TRAITS AND ELEMENTS CONCENTRATION IN MAIZE GERMPLASM ROOTS

    Directory of Open Access Journals (Sweden)

    Andrija Brkić

    2015-06-01

    Full Text Available Western corn rootworm – WCR (Diabrotica virgifera virgifera LeConte is an important maize pest in Croatia. Using native resistance of maize germplasm could reduce chemical treatments and other costs in maize production. Objectives of this study were: i to assess variability of WCR resistance traits (root injury, regrowth and size and concentrations of nine elements in roots of 128 maize genotypes, and ii to determine correlations among the traits and ion concentrations. Results revealed high variability of maize genotypes for both WCR resistance traits and ion concentrations. Significant moderate negative correlations (>-0.4 were detected between root injury and boron as well as between root regrowth and iron, manganese and zinc concentrations in root. Consequently, ion concentration in maize roots might have an impact on WCR resistance research.

  8. Developing an in vivo toxicity assay for RNAi risk assessment in honey bees, Apis mellifera L.

    Science.gov (United States)

    Vélez, Ana María; Jurzenski, Jessica; Matz, Natalie; Zhou, Xuguo; Wang, Haichuan; Ellis, Marion; Siegfried, Blair D

    2016-02-01

    Maize plants expressing dsRNA for the management of Diabrotica virgifera virgifera are likely to be commercially available by the end of this decade. Honey bees, Apis mellifera, can potentially be exposed to pollen from transformed maize expressing dsRNA. Consequently, evaluation of the biological impacts of RNAi in honey bees is a fundamental component for ecological risk assessment. The insecticidal activity of a known lethal dsRNA target for D. v. virgifera, the vATPase subunit A, was evaluated in larval and adult honey bees. Activity of both D. v. virgifera (Dvv)- and A. mellifera (Am)-specific dsRNA was tested by dietary exposure to dsRNA. Larval development, survival, adult eclosion, adult life span and relative gene expression were evaluated. The results of these tests indicated that Dvv vATPase-A dsRNA has limited effects on larval and adult honey bee survival. Importantly, no effects were observed upon exposure of Am vATPase-A dsRNA suggesting that the lack of response involves factors other than sequence specificity. The results from this study provide guidance for future RNAi risk analyses and for the development of a risk assessment framework that incorporates similar hazard assessments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Impact of the nutrients N and K and soluble sugars on Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) and Agrotis ipsilon (Hufnagel) (Lepidoptera, Noctuidae) populations in potato crops, Solanum tuberosum L. (Solanaceae)

    International Nuclear Information System (INIS)

    Azeredo, Edson Henrique de; Lima, Eduardo; Cassino, Paulo Cesar Rodrigues

    2004-01-01

    Impact of the nutrients N and K and soluble sugars on Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) and Agrotis ipsilon (Huefnagel) (Lepidoptera, Noctuidae) populations in potato crops, Solanum tuberosum L. (Solanaceae). The occurrence of Diabrotica speciosa (Germar, 1824) and Agrotis ipsilon (Huefnagel, 1767) on the potato cultivars Achat and Monalisa, influenced by nitrogen and potassium dosage, and minimum quantity of soluble sugars, was studied. The following parameters were evaluated: concentration of mineral nutrient and sugar in green leaf, senescent leaf, leaf in abscission, stem, tubercle and total plant using extracts of infusion in ethanol 80%. The largest infestation of D. speciosa larvae was on Monalisa cultivar at 150 kg.ha -1 of N + K with 27.03% at P -1 , in the absence of potassium. On the other hand, high dosage of K reduced the damages by A. ipsilon on Monalisa cultivar. However, it did not influence the storage of soluble sugar. The results indicated that in Achat cultivar the accumulated soluble sugar was reduced, probably sensitized by elevation of potassic fertilization dosing, differing from Monalisa cultivar, in which the influence was by nitrogen dosing. (author)

  10. Quantitative Trait Loci Mapping of Western Corn Rootworm (Coleoptera: Chrysomelidae) Host Plant Resistance in Two Populations of Doubled Haploid Lines in Maize (Zea mays L.).

    Science.gov (United States)

    Bohn, Martin O; Marroquin, Juan J; Flint-Garcia, Sherry; Dashiell, Kenton; Willmot, David B; Hibbard, Bruce E

    2018-02-09

    Over the last 70 yr, more than 12,000 maize accessions have been screened for their level of resistance to western corn rootworm, Diabrotica virgifera virgifera (LeConte; Coleoptera: Chrysomelidae), larval feeding. Less than 1% of this germplasm was selected for initiating recurrent selection or other breeding programs. Selected genotypes were mostly characterized by large root systems and superior root regrowth after root damage caused by western corn rootworm larvae. However, no hybrids claiming native (i.e., host plant) resistance to western corn rootworm larval feeding are currently commercially available. We investigated the genetic basis of western corn rootworm resistance in maize materials with improved levels of resistance using linkage disequilibrium mapping approaches. Two populations of topcrossed doubled haploid maize lines (DHLs) derived from crosses between resistant and susceptible maize lines were evaluated for their level of resistance in three to four different environments. For each DHL topcross an average root damage score was estimated and used for quantitative trait loci (QTL) analysis. We found genomic regions contributing to western corn rootworm resistance on all maize chromosomes, except for chromosome 4. Models fitting all QTL simultaneously explained about 30 to 50% of the genotypic variance for root damage scores in both mapping populations. Our findings confirm the complex genetic structure of host plant resistance against western corn rootworm larval feeding in maize. Interestingly, three of these QTL regions also carry genes involved in ascorbate biosynthesis, a key compound we hypothesize is involved in the expression of western corn rootworm resistance. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Blended Refuge and Insect Resistance Management for Insecticidal Corn

    Science.gov (United States)

    Crespo, Andre L B; Pan, Zaiqi; Crain, Philip R; Thompson, Stephen D; Pilcher, Clinton D; Sethi, Amit

    2018-01-01

    Abstract In this review, we evaluate the intentional mixing or blending of insecticidal seed with refuge seed for managing resistance by insects to insecticidal corn (Zea mays). We first describe the pest biology and farming practices that will contribute to weighing trade-offs between using block refuges and blended refuges. Case studies are presented to demonstrate how the trade-offs will differ in different systems. We compare biological aspects of several abstract models to guide the reader through the history of modeling, which has played a key role in the promotion or denigration of blending in various scientific debates about insect resistance management for insecticidal crops. We conclude that the use of blended refuge should be considered on a case-by-case basis after evaluation of insect biology, environment, and farmer behavior. For Diabrotica virgifera virgifera, Ostrinia nubilalis, and Helicoverpa zea in the United States, blended refuge provides similar, if not longer, delays in the evolution of resistance compared to separate block refuges. PMID:29220481

  12. Impact of the nutrients N and K and soluble sugars on Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) and Agrotis ipsilon (Hufnagel) (Lepidoptera, Noctuidae) populations in potato crops, Solanum tuberosum L. (Solanaceae); Impacto dos nutrientes N e K e de acucares soluveis sobre populacoes de Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) e Agrotis ipsilon (Hufnagel) (Lepidoptera, Noctuidae) na cultura da batata, Solanum tuberosum L. (Solanaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Azeredo, Edson Henrique de [Universidade Federal Fluminense (UFF), Pinheiral, RJ (Brazil). Pro-Reitoria de Extensao], e-mail: edsonhenrique.azeredo@bol.com.br; Lima, Eduardo [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Inst. de Agronomia. Dept. de Solos; Cassino, Paulo Cesar Rodrigues [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Inst. de Biologia. Centro Integrado de Manejo de Pragas C.R.G.

    2004-03-15

    Impact of the nutrients N and K and soluble sugars on Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) and Agrotis ipsilon (Huefnagel) (Lepidoptera, Noctuidae) populations in potato crops, Solanum tuberosum L. (Solanaceae). The occurrence of Diabrotica speciosa (Germar, 1824) and Agrotis ipsilon (Huefnagel, 1767) on the potato cultivars Achat and Monalisa, influenced by nitrogen and potassium dosage, and minimum quantity of soluble sugars, was studied. The following parameters were evaluated: concentration of mineral nutrient and sugar in green leaf, senescent leaf, leaf in abscission, stem, tubercle and total plant using extracts of infusion in ethanol 80%. The largest infestation of D. speciosa larvae was on Monalisa cultivar at 150 kg.ha{sup -1} of N + K with 27.03% at P< 0,05. It was observed that the effect of the dosage of N + K in the increment of the concentration of soluble sugars increased the damages in the tubercles and stems by A. ipsilon. The infestation by these species increased to 58.82% on the Monalisa cultivar, when the nitrogen dosage increased from zero to 150 kg.ha{sup -1}, in the absence of potassium. On the other hand, high dosage of K reduced the damages by A. ipsilon on Monalisa cultivar. However, it did not influence the storage of soluble sugar. The results indicated that in Achat cultivar the accumulated soluble sugar was reduced, probably sensitized by elevation of potassic fertilization dosing, differing from Monalisa cultivar, in which the influence was by nitrogen dosing. (author)

  13. Transgenic Bt Corn, Soil Insecticide, and Insecticidal Seed Treatment Effects on Corn Rootworm (Coleoptera: Chrysomelidae) Beetle Emergence, Larval Feeding Injury, and Corn Yield in North Dakota.

    Science.gov (United States)

    Calles-Torrez, Veronica; Knodel, Janet J; Boetel, Mark A; Doetkott, Curt D; Podliska, Kellie K; Ransom, Joel K; Beauzay, Patrick; French, B Wade; Fuller, Billy W

    2018-02-09

    Northern, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae), and western, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), corn rootworms are economic pests of corn, Zea mays L. in North America. We measured the impacts of corn hybrids incorporated with Cry3Bb1, Cry34/35Ab1, and pyramided (Cry3Bb1 + Cry34/35Ab1) Bacillus thuringiensis Berliner (Bt) proteins, tefluthrin soil insecticide, and clothianidin insecticidal seed treatment on beetle emergence, larval feeding injury, and corn yield at five locations from 2013 to 2015 in eastern North Dakota. In most cases, emergence was significantly lower in Bt-protected corn than in non-Bt corn hybrids. Exceptions included Wyndmere, ND (2013), where D. barberi emergence from Cry34/35Ab1 plots was not different from that in the non-Bt hybrid, and Arthur, ND (2013), where D. v. virgifera emergence from Cry3Bb1 plots did not differ from that in the non-Bt hybrid. Bt hybrids generally produced increased grain yield compared with non-Bt corn where rootworm densities were high, and larval root-feeding injury was consistently lower in Bt-protected plots than in non-Bt corn. The lowest overall feeding injury and emergence levels occurred in plots planted with the Cry3Bb1 + Cry34/35Ab1 hybrid. Time to 50% cumulative emergence of both species was 5-7 d later in Bt-protected than in non-Bt hybrids. Tefluthrin and clothianidin were mostly inconsequential in relation to beetle emergence and larval root injury. Our findings could suggest that some North Dakota populations could be in early stages of increased tolerance to some Bt toxins; however, Bt corn hybrids currently provide effective protection against rootworm injury in eastern North Dakota. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Manejo de Diabrotica speciosa com atrativos naturais em horta orgânica Natural attractios for management of Diabrotica speciosa in a organic home garden

    OpenAIRE

    João José Stüpp; Mari Inês C Boff; Paulo Antonio de S Gonçalves

    2006-01-01

    O controle de insetos associados ao cultivo de hortaliças é predominantemente realizado através de pesticidas sintéticos. Entretanto, os riscos do uso indiscriminado dos pesticidas sobre a saúde humana e o meio ambiente deve ser considerado. O objetivo deste trabalho foi estudar a eficácia de atrativos naturais no controle da vaquinha Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae), uma praga de importância econômica na América Latina. Os seguintes tratamentos foram testados: raiz de...

  15. Impacto dos nutrientes N e K e de açúcares solúveis sobre populações de Diabrotica speciosa (Germar (Coleoptera, Chrysomelidae e Agrotis ipsilon (Hüfnagel (Lepidoptera, Noctuidae na cultura da batata, Solanum tuberosum L. (Solanaceae Impact of the nutrients N and K and soluble sugars on Diabrotica speciosa (Germar (Coleoptera, Chrysomelidae and Agrotis ipsilon (Hüfnagel (Lepidoptera, Noctuidae populations in potato crops, Solanum tuberosum L. (Solanaceae

    Directory of Open Access Journals (Sweden)

    Edson Henrique de Azeredo

    2004-03-01

    Full Text Available Foi estudada a ocorrência de Diabrotica speciosa (Germar, 1824 (Coleoptera, Chrysomelidae e de Agrotis ipsilon (Hüfnagel, 1767 (Lepidoptera, Noctuidae em plantas de batata, cultivares Achat e Monalisa, influenciadas por dosagens de nitrogênio e potássio, e teor mínimo de açúcares solúveis. Os seguintes parâmetros foram avaliados: concentração de nutrientes minerais e açúcar em folha verde, folha senescente, folha em abcisão, haste, tubérculo e planta total usando extratos de infusão em etanol 80%. A maior infestação por larvas de D. speciosa foi na cultivar Monalisa a 150 kg.ha-1 de N + K com 27,03% a PThe occurrence of Diabrotica speciosa (Germar, 1824 and Agrotis ipsilon (Hüfnagel, 1767 on the potato cultivars Achat and Monalisa, influenced by nitrogen and potassium dosage, and minimum theor of soluble sugars, was studied. The following parameters were evaluated: concentration of mineral nutrient and sugar in green leaf, senescent leaf, leaf in abscission, stem, tubercle and total plant using extracts of infusion in ethanol 80%. The largest infestation of D. speciosa larvae was on Monalisa cultivar at 150 kg.ha-1 of N + K with 27.03% at P< 0,05. It was observed that the effect of the dosage of N + K in the increment of the concentration of soluble sugars increased the damages in the tubercles and stems by A. ipsilon. The infestation by these species increased to 58.82% on the Monalisa cultivar, when the nitrogen dosage increased from zero to 150 kg.ha-1, in the absence of potassium. On the other hand, high dosage of K reduced the damages by A. ipsilon on Monalisa cultivar. However, it did not influence the storage of soluble sugar. The results indicated that in Achat cultivar the accumulated soluble sugar was reduced, probably sensibilized by elevation of potassic fertilization dosing, differing from Monalisa cultivar, in which the influence was by nitrogen dosing.

  16. Attraction of Diabrotica barberi Smith and Lawrence (Coleoptera: Chrysomelidae) to eugenol-baited traps in soybean

    Science.gov (United States)

    Diabrotica barberi Smith and Lawrence (the northern corn rootworm) is a native North American leaf beetle and a major pest of corn. However, adult D. barberi forage in various habitats outside of corn, including soybean, roadside vegetation, and prairie. Eugenol is a common floral volatile that ha...

  17. A novel interaction between plant-beneficial rhizobacteria and roots: colonization induces corn resistance against the root herbivore Diabrotica speciosa.

    Science.gov (United States)

    Santos, Franciele; Peñaflor, Maria Fernanda G V; Paré, Paul W; Sanches, Patrícia A; Kamiya, Aline C; Tonelli, Mateus; Nardi, Cristiane; Bento, José Mauricio S

    2014-01-01

    A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E)-β-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM) program for the protection of corn against the South American corn rootworm, D. speciosa, is considered.

  18. A novel interaction between plant-beneficial rhizobacteria and roots: colonization induces corn resistance against the root herbivore Diabrotica speciosa.

    Directory of Open Access Journals (Sweden)

    Franciele Santos

    Full Text Available A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E-β-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM program for the protection of corn against the South American corn rootworm, D. speciosa, is considered.

  19. Medicinal plant extracts on the control of Diabrotica speciosa (Coleoptera: Chrysomelidae Extratos de plantas medicinais no controle de Diabrotica speciosa (Coleoptera: Chrysomelidae

    Directory of Open Access Journals (Sweden)

    F.S. Barbosa

    2013-01-01

    Full Text Available The aim of this study was to evaluate the insecticidal effect of aqueous, alcoholic, and oil extracts from leaves of eight medicinal plants against Diabrotica speciosa prepared at five concentrations. The extracts that used commercial soybean oil as solvent showed the highest D. speciosa mortality due to the solvent itself, regardless of the used plants and their concentrations. Thus, commercial soybean oil was discarded as solvent since at these volumes it would cause serious phytotoxicity problems. After 24 hours of exposure of the pest to the extracts, the highest D. speciosa mortality values were observed for Copaifera langsdorfii and Chenopodium ambrosioides extracts, both in 5% alcohol, and Artemisia verlotorum, in 10% water. However, in the last mortality assessment (48 h, C. langsdorfii extract in 5% alcohol showed higher mortality of this pest, followed by C. ambrosioides extract in 5% alcohol, compared to the remaining plants.O objetivo deste trabalho foi avaliar o efeito inseticida de extratos aquosos, alcoólicos e oleosos de folhas de oito plantas medicinais contra Diabrotica speciosa preparadas em cinco concentrações. Os extratos que utilizaram óleo de soja comercial como solvente apresentaram as maiores mortalidades de D. speciosa em função do próprio óleo, independentemente das plantas utilizadas em suas concentrações. Sendo assim, o óleo de soja comercial foi descartado como solvente, pois nestes volumes acarretaria sérios problemas de fitotoxidade. Após 24 horas de exposição da praga aos extratos, os maiores valores de mortalidade de D. speciosa foram observados nos extratos de Copaifera Langsdorfii e de Chenopodium ambrosioides, ambos em álcool 5%, e de Artemisia verlotorum, em água 10%. Entretanto, na última avaliação de mortalidade (48 h, o extrato de C. langsdorfii em álcool a 5% apresentou maior mortalidade dessa praga, seguida pelo extrato alcoólico a 5% de C. ambrosioides comparada às demais plantas.

  20. Historical and contemporary population genetics of the invasive western corn rootworm (Coleoptera: Chrysomelidae) in Croatia.

    Science.gov (United States)

    Lemic, D; Mikac, K M; Bažok, R

    2013-08-01

    Classical population genetic analyses were used to investigate populations of the western corn rootworm, Diabrotica virgifera virgifera LeConte, in Croatia in 1996 and 2009. The number of alleles was low in both 1996 and 2009; however, more alleles were found in the putative populations surveyed in 2009. Croatia had only 51% of the alleles recorded from the United States and 69% from Europe. However, 10 private (unique) alleles were found in Croatia, which were not found previously in Europe. Most populations were out of Hardy-Weinberg equilibrium, although no linkage disequilibrium was found. Low to no genetic differentiation was found between population pairwise comparisons in 1996, with a greater level of differentiation found between populations sampled in 2009. Using the program STRUCTURE, a single genetic cluster was found for populations sampled in 1996 and 2009. However, two genetic clusters were detected when the 1996 and 2009 data were combined, indicating significant temporal differentiation. Isolation by distance pattern of gene flow characterized populations sampled in 2009 only when the most distant population of Ogulin (the head of the expansion front) was included in the analysis. When Ogluin was excluded from the 2009 analysis no isolation by distance pattern was found. The possible impact that control practices have had on the population genetics of D. v. virgifera in Croatia from 1996 to 2009 are discussed in light of the temporal genetics differences found.

  1. A Simple and Sensitive Plant-Based Western Corn Rootworm Bioassay Method for Resistance Determination and Event Selection.

    Science.gov (United States)

    Wen, Zhimou; Chen, Jeng Shong

    2018-05-26

    We report here a simple and sensitive plant-based western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), bioassay method that allows for examination of multiple parameters for both plants and insects in a single experimental setup within a short duration. For plants, injury to roots can be visually examined, fresh root weight can be measured, and expression of trait protein in plant roots can be analyzed. For insects, in addition to survival, larval growth and development can be evaluated in several aspects including body weight gain, body length, and head capsule width. We demonstrated using the method that eCry3.1Ab-expressing 5307 corn was very effective against western corn rootworm by eliciting high mortality and significantly inhibiting larval growth and development. We also validated that the method allowed determination of resistance in an eCry3.1Ab-resistant western corn rootworm strain. While data presented in this paper demonstrate the usefulness of the method for selection of events of protein traits and for determination of resistance in laboratory populations, we envision that the method can be applied in much broader applications.

  2. Risk assessment of genetically engineered maize resistant to Diabrotica spp.: Influence on above-ground arthropods in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, W. D.; Hussein, Hany; Sehnal, František

    2015-01-01

    Roč. 10, č. 6 (2015), e0130656 E-ISSN 1932-6203 R&D Projects: GA MZe QH91093 Institutional support: RVO:60077344 Keywords : Diabrotica Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 3.057, year: 2015 http:// journal s.plos.org/plosone/article?id=10.1371/ journal .pone.0130656

  3. Agriculture sows pests: how crop domestication, host shifts, and agricultural intensification can create insect pests from herbivores.

    Science.gov (United States)

    Bernal, Julio S; Medina, Raul F

    2018-04-01

    We argue that agriculture as practiced creates pests. We use three examples (Corn leafhopper, Dalbulus maidis; Western corn rootworm, Diabrotica virgifera virgifera; Cotton fleahopper, Pseudatomoscelis seriatus) to illustrate: firstly, how since its origins, agriculture has proven conducive to transforming selected herbivores into pests, particularly through crop domestication and spread, and agricultural intensification, and; secondly, that the herbivores that became pests were among those hosted by crop wild relatives or associates, and were pre-adapted either as whole species or component subpopulations. Two of our examples, Corn leafhopper and Western corn rootworm, illustrate how following a host shift to a domesticated host, emergent pests 'hopped' onto crops and rode expansion waves to spread far beyond the geographic ranges of their wild hosts. Western corn rootworm exemplifies how an herbivore-tolerant crop was left vulnerable when it was bred for yield and protected with insecticides. Cotton fleahopper illustrates how removing preferred wild host plants from landscapes and replacing them with crops, allows herbivores with flexible host preferences to reach pest-level populations. We conclude by arguing that in the new geological epoch we face, the Anthropocene, we can improve agriculture by looking to our past to identify and avoid missteps of early and recent farmers. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Field Trial Performance of Herculex XTRA (Cry34Ab1/Cry35Ab1) and SmartStax (Cry34Ab1/Cry35Ab1 + Cry3Bb1) Hybrids and Soil Insecticides Against Western and Northern Corn Rootworms (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Johnson, K D; Campbell, L A; Lepping, M D; Rule, D M

    2017-06-01

    Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), and northern corn rootworm, Diabrotica barberi Smith and Lawrence (Coleoptera: Chrysomelidae), are important insect pests in corn, Zea mays L. For more than a decade, growers have been using transgenic plants expressing proteins from the bacterium Bacillus thuringiensis (Bt) to protect corn roots from feeding. In 2011, western corn rootworm populations were reported to have developed resistance to Bt hybrids expressing Cry3Bb1 and later found to be cross-resistant to hybrids expressing mCry3A and eCry3.1Ab. The identification of resistance to Cry3 (Cry3Bb1, mCry3A, and eCry3.1Ab) hybrids led to concerns about durability and efficacy of products with single traits and of products containing a pyramid of a Cry3 protein and the binary Bt proteins Cry34Ab1 and Cry35Ab1. From 2012 to 2014, 43 field trials were conducted across the central United States to estimate root protection provided by plants expressing Cry34Ab1/Cry35Ab1 alone (Herculex RW) or pyramided with Cry3Bb1 (SmartStax). These technologies were evaluated with and without soil-applied insecticides to determine if additional management measures provided benefit where Cry3 performance was reduced. Trials were categorized for analysis based on rootworm damage levels on Cry3-expressing hybrids and rootworm feeding pressure within each trial. Across scenarios, Cry34Ab1/Cry35Ab1 hybrids provided excellent root protection. Pyramided traits provided greater root and yield protection than non-Bt plus a soil-applied insecticide, and only in trials where larval feeding pressure exceeded two nodes of damage did Cry34Ab1/Cry35Ab1 single-trait hybrids and pyramided hybrids show greater root protection from the addition of soil-applied insecticides. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Sterilization of males Diabrotica speciosa (Coleoptera: Chrysomelidae) with gamma irradiation for control in cultures of economic importance

    International Nuclear Information System (INIS)

    Araujo, Marcio Martins

    2017-01-01

    Diabrotica speciosa (Germar, 1824), causes direct and indirect damage on crops by feeding and acting as virus vector for diverse groups of plants. The main control form is the use of agrochemicals so, aiming to manage the population without environment impact, the present work had as objective to determine the dose of gamma radiation that provides male sterility, its foliar consumption and gonads histological changes. Adult males were submitted to gamma radiation ( 60 Co) on the third day after emergence at doses of 0, 25, 50, 75 and 100 Gy at 0,808 KGy/ hour rate, totaling 20 replicates/ dose. The sterilizing dose was based on the fertility of sexually mature non-irradiated females mated by irradiated males. The couples were individualized in 'arenas' and fed with leaflets Phaseolus vulgaris L. with black gauze moistened for oviposition. Eggs were treated and arranged in plastic containers lined with filter paper. After hatching, larvae were transferred to a larger container with a cover cap containing fine vermiculite and maize seedlings (Zea mays L.), which were replaced every 10 days, until adult emergence. After the 4 th day of irradiation, a leaf disc with 3.2 cm in diameter was available for 24 hours for each couple. The discs were scanned and analyzed in ImageJ software. To evaluate the gonads, 3 males with 8 days of age were used per dose. They were dissected in PBS, through the Hematoxylin-Eosin technique the laminas were evaluated under an optical microscope. We observed that male sterility occurred from 75 Gy and the average longevity of this group was of 12.5 days. Consumption of the leaf area by couples composed by a sterile male was 42.9% and the testicular histological analysis demonstrated tissue disorganisation and gaps between germ cells at the highest doses of 75 Gy and 100 Gy. (author)

  6. Physiological time model for predicting adult emergence of western corn rootworm (Coleoptera: Chrysomelidae) in the Texas High Plains.

    Science.gov (United States)

    Stevenson, Douglass E; Michels, Gerald J; Bible, John B; Jackman, John A; Harris, Marvin K

    2008-10-01

    Field observations at three locations in the Texas High Plains were used to develop and validate a degree-day phenology model to predict the onset and proportional emergence of adult Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) adults. Climatic data from the Texas High Plains Potential Evapotranspiration network were used with records of cumulative proportional adult emergence to determine the functional lower developmental temperature, optimum starting date, and the sum of degree-days for phenological events from onset to 99% adult emergence. The model base temperature, 10 degrees C (50 degrees F), corresponds closely to known physiological lower limits for development. The model uses a modified Gompertz equation, y = 96.5 x exp (-(exp(6.0 - 0.00404 x (x - 4.0), where x is cumulative heat (degree-days), to predict y, cumulative proportional emergence expressed as a percentage. The model starts degree-day accumulation on the date of corn, Zea mays L., emergence, and predictions correspond closely to corn phenological stages from tasseling to black layer development. Validation shows the model predicts cumulative proportional adult emergence within a satisfactory interval of 4.5 d. The model is flexible enough to accommodate early planting, late emergence, and the effects of drought and heat stress. The model provides corn producers ample lead time to anticipate and implement adult control practices.

  7. Monitoring presence and advance of the alien invasive western corn rootworm beetle in eastern Slovenia with highly sensitive Metcalf traps.

    Science.gov (United States)

    Hummel, H E; Urek, G; Modic, S; Hein, D F

    2005-01-01

    The American Chrysomelid beetle Diabrotica virgifera virgifera LeConte (D.v.v.), also called the western corn rootworm, spread from the location of its original introduction into Europe, Belgrade airport (BACA 1993), in all directions. Within a decade it occupied almost all countries of South-eastern and Central Europe. However, it reached Slovenia as late as 2003: Only 19 specimen were found in maize fields of the eastern and also western provinces. Already in the summer of 2004, their number had risen to 386 which were mainly found in the eastern provinces near the borders to Croatia, Austria and Hungary. For their monitoring, a simple trap is being described which can be acquired in high numbers at a very low price and can guaranty a most sensitive detection of beetles. The Metcalf cup trap which in Slovenia so far has been unknown performed the task of monitoring quite well at five locations. It will also facilitate the future search for new and increasing infestations. Comparing 2004 with the year 2003, D.v.v. expanded its range in eastern Slovenia by about 15 km. These new infestations will include territories in which fields of the regionally Important oil seed pumpkin Cucurbita pepo are located. With important traffic connections between South-eastern and Central Europe, Slovenia will occupy a bridgehead function in the preventive protection of maize from D.v.v. spreading into more northerly European regions including western Austria and southern Germany.

  8. The effect of nitrogen rate on transgenic corn Cry3Bb1 protein expression.

    Science.gov (United States)

    Marquardt, Paul T; Krupke, Christian H; Camberato, James J; Johnson, William G

    2014-05-01

    Combining herbicide-resistant and Bacillus thuringiensis (Bt) traits in corn (Zea mays L.) hybrids may affect insect resistance management owing to volunteer corn. Some Bt toxins may be expressed at lower levels by nitrogen-deficient corn roots. Corn plants with sublethal levels of Bt expression could accelerate the evolution of Bt resistance in target insects. The present objective was to quantify the concentration of Bt (Cry3Bb1) in corn root tissue with varying tissue nitrogen concentrations. Expression of Cry3Bb1 toxin in root tissue was highly variable, but there were no differences in the overall concentration of Cry3Bb1 expressed between roots taken from Cry3Bb1-positive volunteer and hybrid corn plants. The nitrogen rate did affect Cry3Bb1 expression in the greenhouse, less nitrogen resulted in decreased Cry3Bb1 expression, yet this result was not documented in the field. A positive linear relationship of plant nitrogen status on Cry3Bb1 toxin expression was documented. Also, high variability in Cry3Bb1 expression is potentially problematic from an insect resistance management perspective. This variability could create a mosaic of toxin doses in the field, which does not fit into the high-dose refuge strategy and could alter predictions about the speed of evolution of resistance to Cry3Bb1 in western corn rootworm Diabrotica virgifera virgifera LeConte. © 2013 Society of Chemical Industry.

  9. Sterilization of males Diabrotica speciosa (Coleoptera: Chrysomelidae) with gamma irradiation for control in cultures of economic importance; Esterilização de machos de Diabrotica speciosa (Coleoptera: Chrysomelidae) com irradiação gama visando o controle em culturas de importância econômica

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Marcio Martins

    2017-07-01

    Diabrotica speciosa (Germar, 1824), causes direct and indirect damage on crops by feeding and acting as virus vector for diverse groups of plants. The main control form is the use of agrochemicals so, aiming to manage the population without environment impact, the present work had as objective to determine the dose of gamma radiation that provides male sterility, its foliar consumption and gonads histological changes. Adult males were submitted to gamma radiation ({sup 60}Co) on the third day after emergence at doses of 0, 25, 50, 75 and 100 Gy at 0,808 KGy/ hour rate, totaling 20 replicates/ dose. The sterilizing dose was based on the fertility of sexually mature non-irradiated females mated by irradiated males. The couples were individualized in 'arenas' and fed with leaflets Phaseolus vulgaris L. with black gauze moistened for oviposition. Eggs were treated and arranged in plastic containers lined with filter paper. After hatching, larvae were transferred to a larger container with a cover cap containing fine vermiculite and maize seedlings (Zea mays L.), which were replaced every 10 days, until adult emergence. After the 4{sup th} day of irradiation, a leaf disc with 3.2 cm in diameter was available for 24 hours for each couple. The discs were scanned and analyzed in ImageJ software. To evaluate the gonads, 3 males with 8 days of age were used per dose. They were dissected in PBS, through the Hematoxylin-Eosin technique the laminas were evaluated under an optical microscope. We observed that male sterility occurred from 75 Gy and the average longevity of this group was of 12.5 days. Consumption of the leaf area by couples composed by a sterile male was 42.9% and the testicular histological analysis demonstrated tissue disorganisation and gaps between germ cells at the highest doses of 75 Gy and 100 Gy. (author)

  10. IPM Use With the Deployment of a Non-High Dose Bt Pyramid and Mitigation of Resistance for Western Corn Rootworm (Diabrotica virgifera virgifera).

    Science.gov (United States)

    Martinez, J C; Caprio, M A

    2016-03-27

    Recent detection of western corn rootworm resistance to Bt (Bacillus thuringiensis) corn prompted recommendations for the use of integrated pest management (IPM) with planting refuges to prolong the durability of Bt technologies. We conducted a simulation experiment exploring the effectiveness of various IPM tools at extending durability of pyramided Bt traits. Results indicate that some IPM practices have greater merits than others. Crop rotation was the most effective strategy, followed by increasing the non-Bt refuge size from 5 to 20%. Soil-applied insecticide use for Bt corn did not increase the durability compared with planting Bt with refuges alone, and both projected lower durabilities. When IPM participation with randomly selected management tools was increased at the time of Bt commercialization, durability of pyramided traits increased as well. When non-corn rootworm expressing corn was incorporated as an IPM option, the durability further increased.For corn rootworm, a local resistance phenomenon appeared immediately surrounding the resistant field (hotspot) and spread throughout the local neighborhood in six generations in absence of mitigation. Hotspot mitigation with random selection of strategies was ineffective at slowing resistance, unless crop rotation occurred immediately; regional mitigation was superior to random mitigation in the hotspot and reduced observed resistance allele frequencies in the neighborhood. As resistance alleles of mobile pests can escape hotspots, the scope of mitigation should extend beyond resistant sites. In the case of widespread resistance, regional mitigation was less effective at prolonging the life of the pyramid than IPM with Bt deployment at the time of commercialization. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the United States.

  11. THE INVASIVE COLEOPTEROFAUNA FOR REPUBLIC OF MOLDOVA

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    Asea M. Timuş

    2015-07-01

    Full Text Available The invasive coleopterofauna for Republic of Moldova consists of the 100 species. After correlation local database with Fauna Europaea for our country registered are 31 of species, but for 69 mentioned with the „absent” and 38 „no date”. In the meantime 24 species were recorded for our country: Acanthoscelides abtectus, A.pallidipennis, Alphitobius diaperinus, Alphitophagus bifasciatus, Bruchus pisorum, B.rufimanus, Caulophilus latinasus, Diabrotica virgifera, Gnathocerus cornutus, Harmonia axyridis, Lasioderma serricorne, Leptinotarsa decemlineata, Lignyodes bischoffi, Lithocharis nigriceps, Oryzaephilus surinamensis, Rhyzopertha dominica, Sitophilus granarius, S. oryzae, S. zeamais, Tenebrio molitor, Tenebrioides mauritanicus, Tribolium castaneum, T. destructor, Trogoderma granarium. According periods penetration the invasive beetles it was found that 2 species have entered the XVIII century, 16 species in the XIX, 53 species in the XX and 29 species in the XXI century. The registration invasive beetles in countries of interest to the our country is in: Bulgaria – 54 species; Poland – 39; România – 3; other countries- 4.

  12. Biology of Paenibacillus larvae, a deadly pathogen of honey bee larvae.

    Science.gov (United States)

    Ebeling, Julia; Knispel, Henriette; Hertlein, Gillian; Fünfhaus, Anne; Genersch, Elke

    2016-09-01

    The gram-positive bacterium Paenibacillus larvae is the etiological agent of American Foulbrood of honey bees, a notifiable disease in many countries. Hence, P. larvae can be considered as an entomopathogen of considerable relevance in veterinary medicine. P. larvae is a highly specialized pathogen with only one established host, the honey bee larva. No other natural environment supporting germination and proliferation of P. larvae is known. Over the last decade, tremendous progress in the understanding of P. larvae and its interactions with honey bee larvae at a molecular level has been made. In this review, we will present the recent highlights and developments in P. larvae research and discuss the impact of some of the findings in a broader context to demonstrate what we can learn from studying "exotic" pathogens.

  13. Feeding for larvae of catfish Pangasionodon sp. larvae in different ages

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    Muhammad Agus Suprayudi

    2015-05-01

    Full Text Available ABSTRACT Sludge worm (Tubifex sp. as natural feed on catfish (Pangasionodon sp. larvae rearing is available in limited amount especially during rainy season. It becomes a constraint factor for larvae rearing sector. This research was conducted to evaluate the appropriate initial age of catfish larvae to get artificial feed as sludge worm replacement. Evaluation was conducted on the growth and survival of catfish larvae in 14 days of culture. There were four treatments of feeding in triplicates i.e. larvae were given natural feed without artificial feed, given artificial feed started from d3, d6, and d9 with three replications. The results showed that larvae fed on artificial feed on d3 had the lowest growth compared to the other treatments, whereas the survival was not significantly different (P>0.05 among the treatments. As a conclusion, artificial feed could be used to replace natural feed for catfish larvae started at the age of nine days. Keywords: sludge worm, catfish larvae, artificial feed  ABSTRAK Cacing sutra (Tubifex sp. tersedia dalam jumlah terbatas terutama pada musim penghujan sebagai pakan alami dalam usaha pembenihan ikan patin (Pangasionodon sp.. Ini menjadi kendala dalam usaha pembenihan. Penelitian ini dilakukan untuk mengevaluasi umur larva ikan patin yang tepat untuk mulai diberi pakan buatan menggantikan cacing sutra. Evaluasi dilakukan pada pertumbuhan dan kelangsungan hidup larva ikan patin umur 14 hari. Selama pemeliharaan, larva diberi pakan dengan empat perlakuan; pemberian pakan alami tanpa pakan buatan, pemberian pakan buatan mulai d3, d6, dan d9 dengan tiga ulangan untuk masing-masing perlakuan. Hasil penelitian menunjukkan bahwa perlakuan pemberian pakan buatan mulai d3 memiliki pertumbuhan panjang yang terkecil dibandingkan perlakuan lain, sedangkan tingkat kelangsungan hidup larva tidak berbeda nyata (P>0,05 antarperlakuan. Berdasarkan hasil penelitian, dapat disimpulkan bahwa pakan buatan dapat digunakan

  14. Evaluation of five methods for total DNA extraction from western corn rootworm beetles.

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    Hong Chen

    Full Text Available BACKGROUND: DNA extraction is a routine step in many insect molecular studies. A variety of methods have been used to isolate DNA molecules from insects, and many commercial kits are available. Extraction methods need to be evaluated for their efficiency, cost, and side effects such as DNA degradation during extraction. METHODOLOGY/PRINCIPAL FINDINGS: From individual western corn rootworm beetles, Diabrotica virgifera virgifera, DNA extractions by the SDS method, CTAB method, DNAzol reagent, Puregene solutions and DNeasy column were compared in terms of DNA quantity and quality, cost of materials, and time consumed. Although all five methods resulted in acceptable DNA concentrations and absorbance ratios, the SDS and CTAB methods resulted in higher DNA yield (ng DNA vs. mg tissue at much lower cost and less degradation as revealed on agarose gels. The DNeasy kit was most time-efficient but was the costliest among the methods tested. The effects of ethanol volume, temperature and incubation time on precipitation of DNA were also investigated. The DNA samples obtained by the five methods were tested in PCR for six microsatellites located in various positions of the beetle's genome, and all samples showed successful amplifications. CONCLUSION/SIGNIFICANCE: These evaluations provide a guide for choosing methods of DNA extraction from western corn rootworm beetles based on expected DNA yield and quality, extraction time, cost, and waste control. The extraction conditions for this mid-size insect were optimized. The DNA extracted by the five methods was suitable for further molecular applications such as PCR and sequencing by synthesis.

  15. Key to marine arthropod larvae

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    John A. Fornshell

    2012-03-01

    Full Text Available The scope of this key is restricted to the larvae of marine arthropods. The key is based solely on their morphology, patterns of body segmentation, numbers of appendages, and mode of locomotion. An effort has been made to treat all traditionally named larval forms, both planktonic and benthic. It is intended that this key be useful for a researcher working with archived museum specimens and therefore, does not include habitat information as a identifying trait, even though this information is usually available in the archived records. Within the phylum Arthropoda there are two sub-phyla and eleven classes having larval stages in the marineenvironment. Where feasible the original names of the various larval types have been used. Because this nomenclature is less commonly used today compared to the past, the more recent taxonomic affinities are included in parentheses after the original larval name. The key includes the following thirty-four larvae: Branchhiopoda nauplii; Cephalocarida nauplii; Mystacocarida nauplii; trilobite larva; protonymphon; hexapod larvae; Remipedia nauplii; nauplius - Y larvae; Cirripedia nauplii; Ascothoracida nauplii; Ostracoda nauplii; Euphausiacea nauplii; Penaeidea nauplii; Cyclopoida nauplii; Calanoida nauplii; Harpacticoida nauplii;Polyarthra nauplii; cypris larva; eryonecius larva; cypris-Y larva; elapthocaris larvae; mysis larvae; lucifer zoea; acetes zoea; acanthosoma larva; phyllosoma; antizoea larva; anomuran zoea; brachyuran zoea; calyptopis larvae; furcilia larva; crytopia larva; puerulus larva; alima larva.

  16. CONTROLE QUÍMICO DO PULGÃO VERDE (Myzus persicae Sulzer, 1776 E DA VAQUINHA (Diabrotica speciosa Germ., 1824 NA CULTURA DO TOMATE RASTEIRO CHEMICAL CONTROL OF THE GREEN PEACH APHID (Myzus persicae, SULZER AND TOMATO LEAF BEETLE (Diabrotica speciosa, GERMAR IN TOMATO PLANTS

    Directory of Open Access Journals (Sweden)

    Danilo Couto

    2007-09-01

    Full Text Available

    O efeito de cinco inseticidas aplicados no tomateiro (Lycopersicum sculentum Mill, visando ao controle do pulgão verde, Myzus persicae SULZER e de vaquinha, Diabrotica speciosa GERM, foi testado em um experimento realizado na área experimental do Departamento de Horticultura da Escota de Agronomia da Universidade Federal de Goiás, no período de maio a setembro de 1994. Os tratamentos foram aplicados via pulverização e constaram de Bulldock 125 SC (dosagem de 100 ml/ 100 1 de água; Bulldock 50 CE (25 e 30 ml/100 l de água; Tamaron BR (100 ml/ 100 l de água; Orthene 750 BR (100 ml/ l00 1 de água e Folidol 600 (100 ml/l00 1 de água; e ainda uma testemunha (sem inseticida. Os resultados obtidos mostraram que todos os tratamentos foram eficientes no controle de M. persicae até sete dias após a aplicação. Aos 14 dias após a aplicação, o Bulldock 50 CE na dosagem de 25 ml/ 100 l de água e o Folidol 600 a 100 ml/ 100 l de água não apresentaram eficiência satisfatória. Com relação à D. speciosa, todos esses produtos foram igualmente eficientes até sete dias após aplicação.

    PALAVRAS-CHAVE: Myzus persicae; diabrotica speciosa; tomateiro; controle químico.

    A trial to control the green peach aphid myzus persicae and tomato leaf beetle Diabrotica speciosa was carried out in Goi

  17. Larvae for layers

    DEFF Research Database (Denmark)

    Bjerrum, Lotte; Fischer, Christian Holst; Nordentoft, Steen

    2013-01-01

    Companies and researchers are in close collaboration developing a container- based system for cultivating fly larvae at organic poultry farms. In a one week process, manure will be converted to compost and the live larvae will be harvested and used for feeding laying hens. The larvae are expected...

  18. Larva migrans visceral: relato de caso Visceral larva migrans: case report

    Directory of Open Access Journals (Sweden)

    Alexandre Bortoli Machado

    2003-04-01

    Full Text Available Larva migrans visceral é doença infecciosa, adquirida por ingestão de ovos provenientes dos vermes Toxocara canis e/ou Toxocara cati que infestam cães e gatos; as larvas penetram a parede intestinal e migram através dos tecidos levando a alterações diversas, conseqüentes a uma resposta inflamatória imune.¹ Os autores descrevem um caso clínico de larva migrans visceral com apresentação clínica atípica.Visceral larva migrans is an infectious human disease that occurs following ingestion of eggs from the environment originating from roundworms which commonly infect dogs and cats, Toxocara canis and Toxocara cati. The larvae penetrate the gut wall and migrate through the tissues causing disorders consequent to an inflammatory immune response¹. The authors describe a clinical case of visceral larva migrans with an unusual clinical presentation and also its clinical aspects, diagnosis and treatment are reviewed.

  19. Trap attributes influencing capture of Diabrotica speciosa (Coleoptera: Chrysomelidae on common bean fields Atributos da armadilha influenciam captura de Diabrotica speciosa (Coleoptera: Chrysomelidae em feijoeiro

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    Maurício Ursi Ventura

    2005-08-01

    Full Text Available Refinements in trap characteristics may improve ability to monitor and mass-trap beetles. Field assays were conducted in common bean fields to assess responses of Diabrotica speciosa (Germar to some trap characteristics. Golden yellow plastic cups (750 mL traps caught more D. speciosa females and males than did clear traps. Carrot slices in Petri dishes baited with Lagenaria vulagaris L. powder (cucurbitacin source - 0.28% caught more beetles than did dishes with carrot alone. Dispensers for the floral volatile attractant 1,4-dimethoxybenze were also compared. Rubber septa dispenser attracted more beetles than did control (dental wicks saturated with acetone. Captures on dental wick, starch matrix and feminine pad dispensers were intermediate and did not differ from those on rubber septa and unbaited controls. Perforated bottle traps (2000 mL, when baited with the floral attractant, caught more beetles than did window bottle traps (both traps contained L. vulgaris powder in most assessments done from two to ten days after trap placement in the field. Traps with the insecticide carbaryl captured more beetles than did traps without it, 2-4 and 8-10 days after trap placement in the field, but not in the remaining periods (0-2, 4-6 and 6-8 days. Traps baited with 1,4-dimethoxybenzene captured more beetles than did the unbaited ones in all assessments (each other day from two to ten days after trap placement in the field. Finally, similar amounts of beetles were captured using plastic bottle traps (2000 mL: perforated, window (both with cucurbitacin and sticky (without cucurbitacin traps, when were baited with the floral attractant.Refinamentos em caraterísticas de armadilhas podem incrementar sua habilidade para monitorar e capturar em massa os insetos. Experimentos foram conduzidos em lavoura de feijoeiro para verificar as respostas de Diabrotica speciosa (Germar a algumas características de armadilhas. Armadilhas de copos plástico (750 m

  20. Genetic monitoring of western corn rootworm (Coleoptera: Chrysomelidae) populations on a microgeographic scale.

    Science.gov (United States)

    Ivkosic, S A; Gorman, J; Lemic, D; Mikac, K M

    2014-06-01

    Microsatellite and mitochondrial DNA genetic monitoring of the western corn rootworm, Diabrotica virgifera virgifera LeConte, was undertaken in Croatia and Serbia from 1996 to 2011 and in the United States in 2011. The seven U.S. populations displayed the greatest allelic diversity. In Europe, the highest number of alleles was found in Rugvica, Croatia, and Surčin, Serbia, the two sites closest to international airports. The highest number of mitochondrial (mt) DNA haplotypes was recorded from Croatia in 1996. From 2009 to 2011, haplotype diversity declined, and Croatia and Serbia had a single fixed haplotype. U.S. continuous maize locations had one haplotype, while three haplotypes were found at crop-rotated locations. Minimal temporal genetic differentiation was found within and between populations in Europe and the United States. Bayesian cluster analysis identified two genetic clusters that grouped western corn rootworm from Croatia and Serbia separately from U.S. populations; however, these clusters were not neat, and numerous U.S. individuals had both European and U.S. ancestry, suggesting bidirectional gene flow. Bottlenecks were identified within most Croatian populations sampled in 1996, only two populations in 2009, and in all populations in 2011. Bottlenecks were not identified from Serbia from 1996 to 2011 or from the United States in 2011. As suspected Serbia was identified as the geographic source of western corn rootworm in Croatia. The temporal genetic monitoring undertaken allowed a deeper understanding of the population genetics of western corn rootworm in Croatia, neighboring Serbia, and its geographic source in the United States. The data obtained can be used to inform western corn rootworm pest management strategies in Croatia and Europe.

  1. Isolamento de esporos de Paenibacillus larvae subsp. larvae no Brasil Detectionof Paenibacillus larvae subsp. larvae spores in Brazil

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    Dulce Maria Tocchetto Schuch

    2003-03-01

    Full Text Available Este trabalho objetivou detectar presença de esporos de Paenibacillus larvae subsp. larvae em produtos de um entreposto do interior do Estado do Rio Grande do Sul, a identificação de possíveis fontes de contaminação e a avaliação da possibilidade da transferência de esporos para colméias de apiários adjacentes a partir de produtos importados contaminados. Foram analisados mel e pólen importados disponíveis no entreposto, favo do ninho (crias, pólen e mel colhido de uma colméia sadia, mel estocado em um dos apiários e abelhas adultas. Os resultados foram positivosem relação ao mel e pólen importados, a três grupos de abelhas adultas e ao mel do favo.The objective of this work was to detect the presence of Paenibacillus larvae subsp. larvae spores in products from a warehouse located in Rio Grande do Sul State, Brazil, the identification of possible contamination sources, and the assessment of spores transference possibility from contaminated imported products from the warehouse to apiaries located in the surrounding area. Samples of imported pollen and bulk honey stocked in the warehouse, and honeycomb (brood, honey and pollen from a healthy hive, honey from one apiary and adult bees were analyzed. Imported honey and pollen, and three groups of adult bees and the honey collected from the honeycomb resulted positive.

  2. ISOLASI BACILLUS THURINGIENSIS DARI LARVA DAN PENGUJIAN PATOGENISITASNYA TERHADAP LARVA NYAMUK VEKTOR

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    Blondine Ch. P.

    2012-09-01

    Full Text Available A study to evaluate pathogenic organisms as cause of mosquito larvae death was conducted at Wonokerto and Pabelan villages, Salatiga Luar Kota subdistrict, Semarang regency in Central Java from May 1991 through December 1991. Bacterial isolation from dead larvae showed that 31 B. thuringicnsis isolates were obtained from 31 larvae samples collected from 2 location e.g Wonokerto village (3 samples, Pabelan village (28 samples. Nineteen isolates (61,3% showed a pathogenicity of more than 50% to third toward instar larvae of Aedes aegypti and Culex quinquefasciatus respectively 24 hours after exposure. This study shows the possible use of B. thuringiensis for biologic control of mosquitoes which can act as vectors for human diseases.

  3. Lethal infection thresholds of Paenibacillus larvae for honeybee drone and worker larvae (Apis mellifera).

    Science.gov (United States)

    Behrens, Dieter; Forsgren, Eva; Fries, Ingemar; Moritz, Robin F A

    2010-10-01

    We compared the mortality of honeybee (Apis mellifera) drone and worker larvae from a single queen under controlled in vitro conditions following infection with Paenibacillus larvae, a bacterium causing the brood disease American Foulbrood (AFB). We also determined absolute P. larvae cell numbers and lethal titres in deceased individuals of both sexes up to 8 days post infection using quantitative real-time PCR (qPCR). Our results show that in drones the onset of infection induced mortality is delayed by 1 day, the cumulative mortality is reduced by 10% and P. larvae cell numbers are higher than in worker larvae. Since differences in bacterial cell titres between sexes can be explained by differences in body size, larval size appears to be a key parameter for a lethal threshold in AFB tolerance. Both means and variances for lethal thresholds are similar for drone and worker larvae suggesting that drone resistance phenotypes resemble those of related workers. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

  4. Amostragem por larva-única na vigilância de Aedes aegypti Single-larva sampling for Aedes aegypti surveillance

    Directory of Open Access Journals (Sweden)

    José Eduardo Bracco

    1995-04-01

    Full Text Available Com a finalidade de testar a metodologia de amostragem por larva-única na vigilância entomológica do Aedes aegypti, foram pesquisados domicílios do Município de Araraquara, SP (Brasil. Nos criadouros que continham larvas de Aedes uma delas foi coletada. Como controle, após a coleta da larva-única, todas as larvas foram coletadas para identificação posterior. Esse processo foi repetido no laboratório. Dos 447 domicílios visitados, apenas 12 foram considerados positivos e 20 criadouros foram identificados; destes, 13 continham larvas de Aedes; 5, larvas de Aedes e Culex e 2, larvas de Culex. Os resultados mostram o reconhecimento correto, no campo, de todos os criadouros, evidenciando que o método poderia ser utilizado na vigilância entomológica de municípios sem infestação domiciliar ou infestados apenas com uma única espécie de Aedes.Buildings in Araraquara city, Southeastern Brazil, were searched during a year for the presence of Aedes larvae using single larva sampling in order to check the single-larva methodology. In those breeding places in wich Aedes larvae were found, one of them was collected. As a control, after the single larva had been collected, all the larvae from the breeding place were collected for later identification. This process was repeated in the laboratory. Of the 447 domiciles searched, 12 were considered positive and 20 breeding places were found. Of the breeding places, 13 contained Aedes larvae, 5 both Aedes and Culex larvae and 2 Culex larvae only. The results show that all the breeding places in the field were properly recognited showing the method may be used for Aedes surveillance in cities infested with one species only or without any domiciliary infestation.

  5. THE IMPORTANCE OF WESTERN CORN ROOTWORM IN CONTINUOUS MAIZE

    Directory of Open Access Journals (Sweden)

    Marija Ivezić

    2006-06-01

    Full Text Available Western Corn Rootworm (Diabrotica virgifera virgifera LeConte is considered to be one of the most important and potentially most severe pest of maize worldwide. The pest was detected in Croatia for the first time in 1995. Since then it has been spread over all areas with maize production in Croatia. The economically most efficient and preventive control measure is crop rotation and growing maize hybrids that show tolerance to WCR. The trials were settled in the area near Dubosevica where in 2002 and 2003 the economic damages caused by WCR were up to 80%. The aim of this investigation is to determine damages on maize root caused by WCR and loss in grain yield on commercial maize hybrids in continuous farming. Pheromone traps, type Csal♀m♂N®, were used in order to monitor WCR population dynamics. In the period of two months, 366 WCR adult beetles in total were captured. Root damage was evaluated according to Iowa Node Injury Scale and grain yield was measured and corrected to 14% moisture. Furthermore, the plant lodging, as a consequence of larval feeding, was assessed. The results have shown that root damage for hybrid Bc 5982 was 1.15, and 0.73 damage was on Pr 35p 12 roots. The grain yield obtained from hybrid Bc 5982 was 11.7 t/ha, and Pr 35p 12 had 12.3 t/ha. Statistical analyses showed that there were no significant differences in root damage and losses in grain yield between the two investigated hybrids. Results of this investigation indicate that growing maize for 2 to 3 years in continuous farming, in the same field, would not cause economically significant loss in maize gain yield.

  6. Field-Evolved Resistance to Bt Maize by Western Corn Rootworm

    Science.gov (United States)

    Gassmann, Aaron J.; Petzold-Maxwell, Jennifer L.; Keweshan, Ryan S.; Dunbar, Mike W.

    2011-01-01

    Background Crops engineered to produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are planted on millions of hectares annually, reducing the use of conventional insecticides and suppressing pests. However, the evolution of resistance could cut short these benefits. A primary pest targeted by Bt maize in the United States is the western corn rootworm Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae). Methodology/Principal Findings We report that fields identified by farmers as having severe rootworm feeding injury to Bt maize contained populations of western corn rootworm that displayed significantly higher survival on Cry3Bb1 maize in laboratory bioassays than did western corn rootworm from fields not associated with such feeding injury. In all cases, fields experiencing severe rootworm feeding contained Cry3Bb1 maize. Interviews with farmers indicated that Cry3Bb1 maize had been grown in those fields for at least three consecutive years. There was a significant positive correlation between the number of years Cry3Bb1 maize had been grown in a field and the survival of rootworm populations on Cry3Bb1 maize in bioassays. However, there was no significant correlation among populations for survival on Cry34/35Ab1 maize and Cry3Bb1 maize, suggesting a lack of cross resistance between these Bt toxins. Conclusions/Significance This is the first report of field-evolved resistance to a Bt toxin by the western corn rootworm and by any species of Coleoptera. Insufficient planting of refuges and non-recessive inheritance of resistance may have contributed to resistance. These results suggest that improvements in resistance management and a more integrated approach to the use of Bt crops may be necessary. PMID:21829470

  7. A suite of models to support the quantitative assessment of spread in pest risk analysis.

    Science.gov (United States)

    Robinet, Christelle; Kehlenbeck, Hella; Kriticos, Darren J; Baker, Richard H A; Battisti, Andrea; Brunel, Sarah; Dupin, Maxime; Eyre, Dominic; Faccoli, Massimo; Ilieva, Zhenya; Kenis, Marc; Knight, Jon; Reynaud, Philippe; Yart, Annie; van der Werf, Wopke

    2012-01-01

    Pest Risk Analyses (PRAs) are conducted worldwide to decide whether and how exotic plant pests should be regulated to prevent invasion. There is an increasing demand for science-based risk mapping in PRA. Spread plays a key role in determining the potential distribution of pests, but there is no suitable spread modelling tool available for pest risk analysts. Existing models are species specific, biologically and technically complex, and data hungry. Here we present a set of four simple and generic spread models that can be parameterised with limited data. Simulations with these models generate maps of the potential expansion of an invasive species at continental scale. The models have one to three biological parameters. They differ in whether they treat spatial processes implicitly or explicitly, and in whether they consider pest density or pest presence/absence only. The four models represent four complementary perspectives on the process of invasion and, because they have different initial conditions, they can be considered as alternative scenarios. All models take into account habitat distribution and climate. We present an application of each of the four models to the western corn rootworm, Diabrotica virgifera virgifera, using historic data on its spread in Europe. Further tests as proof of concept were conducted with a broad range of taxa (insects, nematodes, plants, and plant pathogens). Pest risk analysts, the intended model users, found the model outputs to be generally credible and useful. The estimation of parameters from data requires insights into population dynamics theory, and this requires guidance. If used appropriately, these generic spread models provide a transparent and objective tool for evaluating the potential spread of pests in PRAs. Further work is needed to validate models, build familiarity in the user community and create a database of species parameters to help realize their potential in PRA practice.

  8. Baylisascaris Larva Migrans

    Science.gov (United States)

    Kazacos, Kevin R.; Abbott, Rachel C.; van Riper, Charles

    2016-05-26

    SummaryBaylisascaris procyonis, the common raccoon roundworm, is the most commonly recognized cause of clinical larva migrans (LM) in animals, a condition in which an immature parasitic worm or larva migrates in a host animal’s tissues, causing obvious disease. Infection with B. procyonis is best known as a cause of fatal or severe neurologic disease that results when the larvae invade the brain, the spinal cord, or both; this condition is known as neural larva migrans (NLM). Baylisascariasis is a zoonotic disease, that is, one that is transmissible from animals to humans. In humans, B. procyonis can cause damaging visceral (VLM), ocular (OLM), and neural larva migrans. Due to the ubiquity of infected raccoons around humans, there is considerable human exposure and risk of infection with this parasite. The remarkable disease-producing capability of B. procyonis in animals and humans is one of the most significant aspects of the biology of ascarids (large roundworms) to come to light in recent years. Infection with B. procyonis has important health implications for a wide variety of free-ranging and captive wildlife, zoo animals, domestic animals, as well as human beings, on both an individual and population level. This report, eighth in the series of U.S. Geological Survey Circulars on zoonotic diseases, will help us to better understand the routes of Baylisascaris procyonis infections and how best to adequately monitor this zoonotic disease.

  9. Visceral larva migrans: case report

    OpenAIRE

    Machado, Alexandre Bortoli; El Achkar, Marice Emanuela

    2003-01-01

    Larva migrans visceral é doença infecciosa, adquirida por ingestão de ovos provenientes dos vermes Toxocara canis e/ou Toxocara cati que infestam cães e gatos; as larvas penetram a parede intestinal e migram através dos tecidos levando a alterações diversas, conseqüentes a uma resposta inflamatória imune.¹ Os autores descrevem um caso clínico de larva migrans visceral com apresentação clínica atípica.Visceral larva migrans is an infectious human disease that occurs following ingestion of eggs...

  10. Feeding preference of Diabrotica speciosa (Ger. (Coleoptera: Chrysomelidae by broccoli leaves from natural, organic and conventional farming systems/ Preferência alimentar de Diabrotica speciosa (Ger. (Coleoptera: Chrysomelidae por folhas de brócolos cultivado em sistema natural, orgânico e convencional

    Directory of Open Access Journals (Sweden)

    Pedro Manuel O. J. Neves

    2006-06-01

    Full Text Available Multiple-choice laboratory tests were achieved to compare feeding preference of Diabrotica speciosa (Ger. to leaves of broccoli (Brassica oleraceae L. var. italica from natural, conventional and organic farming systems. Natural farming systems included incorporation of the elephant grass Pennisetum purpureum Schumacher cv. Napier (50 ton/ha, Bokashi compost (1.5 ton/ha and spray of EM 4 (Natural 1, or the incorporation of the Bokashi compost (1.5 ton /ha and spray of EM 4 (Natural 2, and in the conventional, NPK + borax were incorporated in the planting + dressing N and organic compost (1 kg/ plant was incorporated in the organic system. Organic compost was prepared using crop residues of corn (Zea mays L., soybean [Glycine max (L. Mer.], and cattle manure. Leaf discs were collected and placed in cages in multiple-choice tests. Beetles preferred mostly broccoli leaves from conventional farming system than leaves from Natural (1 and 2 and Organic farming systems. Feeding on leaves from Natural 1, Natural 2 and Organic farming system were 68, 67 and 57% of the feeding on leaves from Conventional farming system.Testes de múltipla escola foram realizados para comparar a preferência alimentar de Diabrotica speciosa (Ger. por folhas de brócolos (Brassica oleraceae L. var. italica cultivado em sistema natural, convencional e orgânico. No sistema natural de cultivo houve a incorporação de capim elefante Pennisetum purpureum Schumacher cv. Napier (50 ton/ha, composto Bokashi (1,5 ton/ha e pulverização de EM 4 (Natural 1, ou a incorporação do composto Bokashi (1,5 ton/ha e pulverização do EM 4 (Natural 2, no sistema convencional houve a incorporação do NPK + borax + N em cobertura, e no sistema orgânico incorporouse composto orgânico (1 kg/planta. O composto orgânico foi preparado utilizando-se resíduos de milho (Zea mays L. e soja [Glycine max (L. Mer.] e esterco de gado. Folhas foram retiradas das plantas das quais foram separados

  11. Extreme morphologies of mantis shrimp larvae

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    Carolin Haug

    Full Text Available ABSTRACT Larvae of stomatopods (mantis shrimps are generally categorized into four larval types: antizoea, pseudozoea (both representing early larval stages, alima and erichthus (the latter two representing later larval stages. These categories, however, do not reflect the existing morphological diversity of stomatopod larvae, which is largely unstudied. We describe here four previously unknown larval types with extreme morphologies. All specimens were found in the collections of the Zoological Museum, University of Copenhagen and were collected during the Danish Dana Expedition round the world 1928-30. These new larval types all represent erichthus-type larvae, especially differing in their shield morphologies. The shield morphology ranges from almost spherical to rather disc-like, with sometimes extremely elongated spines, but only a general systematic assignment of the larvae was possible. Further investigations of these larvae are crucial to understand their life habits and ecological impact, especially as stomatopod and other crustacean larvae might have a much more important position in the marine ecosystems than their corresponding adults.

  12. Self mixing of fly larvae during feeding

    Science.gov (United States)

    Shishkov, Olga; Johnson, Christopher; Hu, David

    How do we sustainably feed a growing world population? One solution of increasing interest is the use of black solider fly larvae, pea-sized grubs envisioned to transform hundreds of tons of food waste into a sustainable protein source. Although startups across the world are raising these larvae, a physical understanding of how they should be raised and fed remains missing. In this study, we present experiments measuring their feeding rate as a function of number of larvae. We show that larger groups of larvae have greater mixing which entrains hungry larvae around the food, increasing feeding rate. Feeding of larvae thus differs from feeding of cattle or other livestock which exhibit less self-mixing.

  13. Métodos de extração e concentrações no efeito inseticida de Ruta graveolens L., Artemisia verlotorum Lamotte e Petiveria alliacea L. a Diabrotica speciosa Germar Extraction methods and concentrations for the insecticidal effect of Ruta graveolens L., Artemisia verlotorum Lamotte, and Petiveria alliacea L. against Diabrotica speciosa Germar

    Directory of Open Access Journals (Sweden)

    F.S. Barbosa

    2009-01-01

    Full Text Available O objetivo deste trabalho foi determinar o melhor método de extração e concentração para Ruta graveolens L. (Rutaceae, Artemisia verlotorum Lamotte (Asteraceae e Petiveria alliacea L. (Phytolaccaceae quanto ao efeito inseticida a Diabrotica speciosa Germar (Coleoptera: Chrysomelidae. Os extratos que utilizaram óleo de soja comercial, pelo menos como um dos solventes, apresentaram maior mortalidade de D. speciosa em suas testemunhas (solvente = óleo, nas três plantas estudadas, em relação às suas concentrações. O extrato aquoso de R. graveolens, a 5% de concentração, apresentou maior mortalidade corrigida de D. speciosa (32,5% que os extratos de A. verlotorum em água (10% de concentração (20,3% e P. alliacea em álcool etílico (2% de concentração (12,5%. O método de extração com água é simples, sendo passível de utilização por pequenos agricultores. A R. graveolens é planta facilmente cultivada, sendo, portanto, boa alternativa de controle dessa praga.The aim of this work was to determine the best extraction method and concentration for Ruta graveolens L. (Rutaceae, Artemisia verlotorum Lamotte (Asteraceae and Petiveria alliacea L. (Phytolaccaceae concerning their insecticidal effect against Diabrotica speciosa Germar (Coleoptera: Chrysomelidae. Extracts using commercial soybean oil as at least one of the solvents resulted in higher D. speciosa mortality in controls (solvent = oil of the three studied plants, relative to their treatment concentrations. R. graveolens extract in water, at 5% concentration, showed higher D. speciosa corrected mortality (32.5% than A. verlotiorum extracts in water (10% concentration (20.3% and P. alliacea in ethanol (2% concentration (12.5%. The extraction method with water is simple and can be used by small farmers. R. graveolens is an easily cultivated plant and constitutes, therefore, a good alternative to control this plague.

  14. Acute toxicity of sodium metabisulphite in larvae and post-larvae of the land crab, Cardisoma guanhumi.

    Science.gov (United States)

    Galli, Orlando B S; Fujimoto, Rodrigo Y; Abrunhosa, Fernando A

    2012-08-01

    Sodium metabisulphite (SMB) is used in marine shrimp aquaculture to prevent the occurrence of black spot. The release SMB into the estuarine environment from shrimp farm pond effluents has been reported. This study evaluated the susceptibility of larvae and post-larvae of land crab, Cardisoma guanhumi to this salt. A decrease in dissolved oxygen and pH occurred with increasing concentration of SMB and exposure time. LC(50) values after 48 h of exposure were 34 ± 1.1 mg/L, 31.1 ± 1.9 mg/L, and 30.6 ± 0.5 mg/L for I zoea larvae, megalopa larvae and stage I juveniles, respectively.

  15. Transcriptional response of honey bee larvae infected with the bacterial pathogen Paenibacillus larvae.

    Science.gov (United States)

    Cornman, Robert Scott; Lopez, Dawn; Evans, Jay D

    2013-01-01

    American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and a general immunity is achieved by larvae as they age, the basis of which has not been identified. To quickly identify a pool of candidate genes responsive to P. larvae infection, we sequenced transcripts from larvae inoculated with P. larvae at 12 hours post-emergence and incubated for 72 hours, and compared expression levels to a control cohort. We identified 75 genes with significantly higher expression and six genes with significantly lower expression. In addition to several antimicrobial peptides, two genes encoding peritrophic-matrix domains were also up-regulated. Extracellular matrix proteins, proteases/protease inhibitors, and members of the Osiris gene family were prevalent among differentially regulated genes. However, analysis of Drosophila homologs of differentially expressed genes revealed spatial and temporal patterns consistent with developmental asynchrony as a likely confounder of our results. We therefore used qPCR to measure the consistency of gene expression changes for a subset of differentially expressed genes. A replicate experiment sampled at both 48 and 72 hours post infection allowed further discrimination of genes likely to be involved in host response. The consistently responsive genes in our test set included a hymenopteran-specific protein tyrosine kinase, a hymenopteran specific serine endopeptidase, a cytochrome P450 (CYP9Q1), and a homolog of trynity, a zona pellucida domain protein. Of the known honey bee antimicrobial peptides, apidaecin was responsive at both time-points studied whereas hymenoptaecin was more consistent in its level of change between biological replicates and had the greatest increase in expression by RNA-seq analysis.

  16. PERKEMBANGAN ENZIM PENCERNAAN LARVA IKAN PATIN, Pangasius hypophthalmus sp.

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    Irzal Effendi

    2003-05-01

    Full Text Available Development of digestive enzymes; protease, lipase and amylase were observed in patin catfish, Pangasius hypophthalmus, larvae.  The 1 day old larvae (day after hatching, with 3,37-3,97 mm length and 0,62-0,79 mg weight, were reared in aquarium 60x50x40 cm with stocking  density of 20 fish/l.  Larvae were fed  Artemia dan tubificid worms 2-8 dan 7-15 days after hatching (dAH,  respectively (schedule I;  2-6 and  5-15 dAH (schedule II; and 2-4 and 5-15 dAH (schedule III.  Chlorella was ready to eat by larvae at the entirely rearing.  For enzyme assay, larvae were sampled from each aquarium at stages of 1, 2, 3, 5, 7, 10 and 15 dAH.    Protease and lipase activity were detected in digestive tract of  1 dAH larvae.   Digestive enzymes development have a similar pattern in larvae for all feeding schedules.  Protease activity  decreased with the increasing of age until 3 dAH, then increased  until the larvae reached 7 dAH, and sharply decreased until 10 dAH and then slowly decreased thereafter. Lipase activity tended to increase slowly with age up to 3 dAH, and increased sharply until 5 dAH, and then decreased sharply until 7 dAH  before decreased again up to the end of rearing.  Amylase activity in larvae increased slowly with the increasing of age up to 5 dAH, then increased sharply until 7 dAH, and decreased thereafter.  In dimly lighted larvae, amylase activity decreased before increased up to 12 d AH, then decreased thereafter.  The amount of food organisms in larval gut, body weight and length, and survival rate of larvae were also measured and discussed.Key Words:  Digestive enzymes, development, larvae, patin catfish, Pangasius hypophthalmus ABSTRAKPenelitian ini bertujuan untuk mengetahui perkembangan enzim protease, lipase dan amilase saluran pencernaan larva ikan patin akibat perubahan skedul pemberian pakan.  Larva ikan patin (panjang 3,77–3,97 mm dan bobot 0,62-0,79 mg berumur 1 hari dipelihara di akuarium 60x

  17. First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera

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    Susana Trivinho-Strixino

    2012-09-01

    Full Text Available First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera. This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalopteran larvae had 24 Temnocephala sp. associated. Furthermore, eight of these Temnocephala worms had chironomid larvae in their gut contents, an interaction previously unknown. Gut content analyses revealed Corynoneura as the commonest chironomid, but larvae of Larsia, Rheotanytarsus and Tanytarsus were recorded as well. This study included Corydalus and Protochauliodes as hosts for Temnocephala, which might be important for this worm dispersion and population dynamics.

  18. Long-wavelength photosensitivity in coral planula larvae.

    Science.gov (United States)

    Mason, Benjamin M; Cohen, Jonathan H

    2012-04-01

    Light influences the swimming behavior and settlement of the planktonic planula larvae of coral, but little is known regarding the photosensory biology of coral at this or any life-history stage. Here we used changes in the electrical activity of coral planula tissue upon light flashes to investigate the photosensitivity of the larvae. Recordings were made from five species: two whose larvae are brooded and contain algal symbionts (Porites astreoides and Agaricia agaricites), and three whose larvae are spawned and lack algal symbionts (Acropora cervicornis, Acropora palmata,and Montastrea faveolata). Photosensitivity originated from the coral larva rather than from, or in addition to, its algal symbionts as species with and without symbionts displayed similar tissue-level electrical responses to light. All species exhibited as much (or more) sensitivity to red stimuli as to blue/green stimuli, which is consistent with a role for long-wavelength visible light in the preference for substrata observed during settlement and in facilitating vertical positioning of larvae in the water column.

  19. Descrição da larva de Erythemis mithroides (Brauer e notas sobre outras larvas conhecidas do gênero (Odonata, Libellulidae Description of the larva of Erythemis mithroides (Brauer and notes on other known larvae of the genus (Odonata, Libellulidae

    Directory of Open Access Journals (Sweden)

    J.M. Costa

    1993-01-01

    Full Text Available The last instar larva of Erythemis mithroides (Brauer, 1900 is described and figured based on exuviae of reared specimens. A comparative analysis of this immature stage and the known larvae of the genus are furnished according to the data available in the literature and of specimens of E credula (Hagen, 1861 and E. vesiculosa (Fab., 1775 permiting a diagnose for the larvae of the genus Erylhemis Hagen, 1861.

  20. Fate of pharmaceuticals and pesticides in fly larvae composting

    Energy Technology Data Exchange (ETDEWEB)

    Lalander, C., E-mail: cecilia.lalander@slu.se [Department of Energy and Technology, Swedish University of Agricultural Sciences (Sweden); Senecal, J.; Gros Calvo, M. [Department of Energy and Technology, Swedish University of Agricultural Sciences (Sweden); Ahrens, L.; Josefsson, S.; Wiberg, K. [Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (Sweden); Vinnerås, B. [Department of Energy and Technology, Swedish University of Agricultural Sciences (Sweden)

    2016-09-15

    A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (< 10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment. - Highlights: • Degradation of pharmaceuticals and pesticides in fly larvae composting (FLC). • Half-life considerably shorter in FLC than in control with no larvae. • Half-life of carbamazepine was less than two days in FLC. • No bioaccumulation in larvae detected. • FLC could impede the spreading of pharmaceuticals and pesticide in the environment.

  1. Fate of pharmaceuticals and pesticides in fly larvae composting

    International Nuclear Information System (INIS)

    Lalander, C.; Senecal, J.; Gros Calvo, M.; Ahrens, L.; Josefsson, S.; Wiberg, K.; Vinnerås, B.

    2016-01-01

    A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (< 10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment. - Highlights: • Degradation of pharmaceuticals and pesticides in fly larvae composting (FLC). • Half-life considerably shorter in FLC than in control with no larvae. • Half-life of carbamazepine was less than two days in FLC. • No bioaccumulation in larvae detected. • FLC could impede the spreading of pharmaceuticals and pesticide in the environment.

  2. Effects of various diets on the calcium and phosphorus composition of mealworms (Tenebrio molitor larvae) and superworms (Zophobas morio larvae).

    Science.gov (United States)

    Latney, La'Toya V; Toddes, Barbara D; Wyre, Nicole R; Brown, Dorothy C; Michel, Kathryn E; Briscoe, Johanna A

    2017-02-01

    OBJECTIVE To evaluate whether the nutritive quality of Tenebrio molitor larvae and Zophobas morio larvae, which are commonly cultured as live food sources, is influenced by 4 commercially available diets used as nutritional substrates; identify which diet best improved calcium content of larvae; and identify the feeding time interval that assured the highest calcium intake by larvae. ANIMALS 2,000 Zophobas morio larvae (ie, superworms) and 7,500 Tenebrio molitor larvae (ie, mealworms). PROCEDURES Larvae were placed in control and diet treatment groups for 2-, 7-, and 10-day intervals. Treatment diets were as follows: wheat millings, avian hand feeding formula, organic avian mash diet, and a high-calcium cricket feed. Control groups received water only. After treatment, larvae were flash-frozen live with liquid nitrogen in preparation for complete proximate and mineral analyses. Analyses for the 2-day treatment group were performed in triplicate. RESULTS The nutrient composition of the high-calcium cricket feed groups had significant changes in calcium content, phosphorus content, and metabolizable energy at the 2-day interval, compared with other treatment groups, for both mealworms and superworms. Calcium content and calcium-to-phosphorus ratios for larvae in the high-calcium cricket feed group were the highest among the diet treatments for all treatment intervals and for both larval species. CONCLUSIONS AND CLINICAL RELEVANCE A 2-day interval with the high-calcium cricket feed achieved a larval nutrient composition sufficient to meet National Research Council dietary calcium recommendations for nonlactating rats. Mealworm calcium composition reached 2,420 g/1,000 kcal at 48 hours, and superworm calcium composition reached 2,070g/1,000 kcal at 48 hours. These findings may enable pet owners, veterinarians, insect breeders, and zoo curators to optimize nutritive content of larvae fed to insectivorous animals.

  3. Image-based automatic recognition of larvae

    Science.gov (United States)

    Sang, Ru; Yu, Guiying; Fan, Weijun; Guo, Tiantai

    2010-08-01

    As the main objects, imagoes have been researched in quarantine pest recognition in these days. However, pests in their larval stage are latent, and the larvae spread abroad much easily with the circulation of agricultural and forest products. It is presented in this paper that, as the new research objects, larvae are recognized by means of machine vision, image processing and pattern recognition. More visional information is reserved and the recognition rate is improved as color image segmentation is applied to images of larvae. Along with the characteristics of affine invariance, perspective invariance and brightness invariance, scale invariant feature transform (SIFT) is adopted for the feature extraction. The neural network algorithm is utilized for pattern recognition, and the automatic identification of larvae images is successfully achieved with satisfactory results.

  4. Feeding behavior of giant gourami, Osphronemus gouramy (Lacepede larvae

    Directory of Open Access Journals (Sweden)

    Thumronk Amornsakun

    2014-06-01

    Full Text Available Feeding experiments were carried out in 15-liter glass aquaria with 10 liters of water containing 1000 larvae aged 1.5 days post-hatching (before mouth opening in three replicates. It was found that the feeding scheme of larval giant gourami aged 5-17 days (TL 8.36-13.40 mm consumed Moina. The larvae aged 14-17 days (TL 12.40-13.40 mm consumed both Moina and artificial pellet. Larvae aged more than 18-days (TL 13.60 mm consumed only artificial pellet. Daily food uptake by the larvae and juvenile were determined in a 15-liter aquaria (water volume 10 liters containing 500 larvae. The larvae were fed with Moina at density of 10 ind/ml. Aquaria without larvae were also set for a control of natural fluctuation in food density. The amount of food intake was calculated based on changes of food density in the aquarium with and without fish larvae. It was found the average uptake of Moina in digestive tract per day of larvae aged 5, 8, 11, 14 and 17 days old were 38, 52, 182, 205 and 266 individual/larva, respectively at density of 1.27, 1.73, 6.07, 6.83, and 8.87 individual/ml, respectively.

  5. Refuge or reservoir? The potential impacts of the biofuel crop Miscanthus x giganteus on a major pest of maize.

    Directory of Open Access Journals (Sweden)

    Joseph L Spencer

    Full Text Available BACKGROUND: Interest in the cultivation of biomass crops like the C4 grass Miscanthus x giganteus (Miscanthus is increasing as global demand for biofuel grows. In the US, Miscanthus is promoted as a crop well-suited to the Corn Belt where it could be cultivated on marginal land interposed with maize and soybean. Interactions (direct and indirect of Miscanthus, maize, and the major Corn Belt pest of maize, the western corn rootworm, (Diabrotica virgifera virgifera LeConte, WCR are unknown. Adding a perennial grass/biomass crop to this system is concerning since WCR is adapted to the continuous availability of its grass host, maize (Zea mays. METHODOLOGY/PRINCIPAL FINDINGS: In a greenhouse and field study, we investigated WCR development and oviposition on Miscanthus. The suitability of Miscanthus for WCR development varied across different WCR populations. Data trends indicate that WCR populations that express behavioural resistance to crop rotation performed as well on Miscanthus as on maize. Over the entire study, total adult WCR emergence from Miscanthus (212 WCR was 29.6% of that from maize (717 WCR. Adult dry weight was 75-80% that of WCR from maize; female emergence patterns on Miscanthus were similar to females developing on maize. There was no difference in the mean no. of WCR eggs laid at the base of Miscanthus and maize in the field. CONCLUSIONS/SIGNIFICANCE: Field oviposition and significant WCR emergence from Miscanthus raises many questions about the nature of likely interactions between Miscanthus, maize and WCR and the potential for Miscanthus to act as a refuge or reservoir for Corn Belt WCR. Responsible consideration of the benefits and risks associated with Corn Belt Miscanthus are critical to protecting an agroecosystem that we depend on for food, feed, and increasingly, fuel. Implications for European agroecosystems in which Miscanthus is being proposed are also discussed in light of the WCR's recent invasion into Europe.

  6. The Identification of Congeners and Aliens by Drosophila Larvae.

    Directory of Open Access Journals (Sweden)

    Francisco Del Pino

    Full Text Available We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b, Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles.

  7. Larva migrans visceral: relato de caso

    OpenAIRE

    Machado Alexandre Bortoli; El Achkar Marice Emanuela

    2003-01-01

    Larva migrans visceral é doença infecciosa, adquirida por ingestão de ovos provenientes dos vermes Toxocara canis e/ou Toxocara cati que infestam cães e gatos; as larvas penetram a parede intestinal e migram através dos tecidos levando a alterações diversas, conseqüentes a uma resposta inflamatória imune.¹ Os autores descrevem um caso clínico de larva migrans visceral com apresentação clínica atípica.

  8. Efektivitas Bacillus thuringiensis dalam Pengendalian Larva Nyamuk Anopheles sp.

    Directory of Open Access Journals (Sweden)

    Citra Inneke Wibowo

    2017-08-01

    Full Text Available Nyamuk Anopheles sp adalah vektor penyakit malaria. Pengendalian vektor penyakit malaria dapat dilakukan secara biologis yaitu dengan menggunakan Bacillus thuringiensis. Tujuan penelitian adalah untuk mengetahui efektivitas konsentrasi Bacillus thuringiensis dalam pengendalian larva nyamuk Anopheles sp.Penelitian ini dilakukan secara eksperimental menggunakan Rancangan Acak Lengkap Faktorial (RAL Faktorial yang terdiri atas dua faktor yaitu konsentrasi Bacillus thuringiensis dan stadia larva Anopheles dengan pengulangan tiga kali.Perlakuan yang dicobakan adalahkonsentrasi Bacillus thuringiensis (A yang terdiri atas 5 taraf:A0: konsentrasi B.thuringiensis 0 CFU.mL-1, A1: konsentrasi B.thuringiensis 102 CFU.mL-1, A2: konsentrasi B.thuringiensis 104 CFU.mL-1, A3: konsentrasi B.thuringiensis 106CFU.mL-1, A4: konsentrasi B.thuringiensis 108CFU.mL-1. Perlakuan tahapan instar larva Anopheles sp. (B adalah sebagai berikut:B1: stadia larva instar I, B2: stadia larva instar II, B3: stadia larva instar III, B4: stadia larva instar IVsehingga terdapat 60 satuan percobaan. Hasil penelitian  menunjukkan konsentrasi B. thuringiensis isolat CK dan IPB CC yang paling berpengaruh dalam pengendalian larva Anopheles sp adalah 108 CFU.mL-1 . Instar larva yang paling peka terhadap B. thuringiensis isolat IPB CC adalah instar I dan II sedangkan instar yang peka terhadap isolat CK adalah instar II, Perlakuan konsentrasi isolat B. thuringiensis dan tingkat instar larva yang paling baik dalam pengendalian larva Anopheles sp. adalah 108 CFU.mL-1, dan instar I dan II.

  9. Biofilms and Marine Invertebrate Larvae: What Bacteria Produce That Larvae Use to Choose Settlement Sites

    Science.gov (United States)

    Hadfield, Michael G.

    2011-01-01

    Communities of microorganisms form thin coats across solid surfaces in the sea. Larvae of many marine invertebrates use biofilm components as cues to appropriate settlement sites. Research on the tube-dwelling polychaete worm Hydroides elegans, a globally common member of biofouling communities, is described to exemplify approaches to understanding biofilm bacteria as a source of settlement cues and larvae as bearers of receptors for bacterial cues. The association of species of the bacterial genus Pseudoalteromonas with larval settlement in many phyla is described, and the question of whether cues are soluble or surface-bound is reviewed, concluding that most evidence points to surface-bound cues. Seemingly contradictory data for stimulation of barnacle settlement are discussed; possibly both explanations are true. Paleontological evidence reveals a relationship between metazoans and biofilms very early in metazoan evolution, and thus the receptors for bacterial cues of invertebrate larvae are very old and possibly unique. Finally, despite more than 60 years of intense investigation, we still know very little about either the bacterial ligands that stimulate larval settlement or the cellular basis of their detection by larvae.

  10. Survival of mayfly larvae under mine acid conditions

    Energy Technology Data Exchange (ETDEWEB)

    Napier, S. Jr.; Hummon, W.D.

    1976-01-01

    Mayfly larvae were abundant and diverse in riffle zones of three control streams in southeastern Ohio. But none were found in such zones of three streams having current or past histories of mine acid pollution, despite vegetative recovery of reclaimed land bordering two of the streams. Laboratory studies showed stepwise increases in non-predatory mortality of mayfly larvae with increased mine acidity. Dragonfly larvae predation on mayfly larvae was constant at pH 8.1 to 4.1, but decreased at pH 3.1 despite tolerance of dragonfly larvae to low pH conditions. Extensive acid mine pollution thus may threaten aquatic biota through removal of food sources or reduced feeding rates as well as through direct mortality.

  11. Freshly squeezed: anaphylaxis caused by drone larvae juice.

    Science.gov (United States)

    Stoevesandt, J; Trautmann, A

    2017-11-30

    Drone larvae are mostly considered a by-product of beekeeping, but have recently been advo-cated as a high-protein source of food. There are as yet no data concerning their allergenic po-tential. We report on a 29-year old bee keeper who experienced an anaphylactic reaction following the consumption of a freshly prepared beverage from raw drone larvae. Larvae-specific sensitization was confirmed by prick-to-prick and basophil activation testing. Bee stings and classical bee products including honey and royal jelly were tolerated. This is the hitherto first report on IgE-mediated allergy to drone larvae. We suggest that a certain awareness towards the allergenicity of bee larvae is required.

  12. [Biotechnological aspects in "loco" larvae].

    Science.gov (United States)

    Inestrosa, N C; Labarca, R; Perelman, A; Campos, E O; Araneda, R; González, M; Brandan, E; Sánchez, J P; González-Plaza, R

    1990-10-01

    The biology of planktotrophic larvae of Concholepas concholepas is the main bottleneck towards developing biotechnologies to rear this muricid. Data concerning planktonic larvae development, diets and environmental signals triggering larval settlement and recruitment is scarce. We have begun the study of the molecular and cell biology of embryos, larvae and recruits having as a final goal, the development of appropriate biotechnologies to rear this gastropod. First, an inverse ratio between BuChE and AChE enzyme activities was established. This ratio may be a precise developmental marker for this species. Second, for the first time a phosphoinositide related regulatory pathway is reported in a muricid, opening a new approach to the biotechnological management of larvae. Third, the relation between sulfate in sea water and larval motility was studied. Concentrations below 125 microM sulfate decreases larval motility. The sulfate is incorporated in proteoglycans which participate in different developmental phenomena. Lastly, a genomic Concholepas concholepas DNA sequence, similar to that of a human growth hormone probe was detected. This is very interesting since growth factors are key molecules during development, growth and are involved in food conversion rates in fish and also, in a variety of marine invertebrates.

  13. SEBARAN LARVA IKAN DAN KAITANNYA DENGAN KONDISI OSEANOGRAFI LAUT SULAWESI

    Directory of Open Access Journals (Sweden)

    Khairul Amri

    2015-06-01

    Full Text Available Laut Sulawesi diketahui sebagai daerah penangkapan ikan yang potensial sekaligus diduga sebagai lokasi pemijahan. Berbagai jenis larva ikan pelagis maupun demersal ditemukan di perairan ini. Kelimpahan dan sebaran larva ikan di suatu perairan sangat dipengaruhi oleh kondisi oseanografi seperti temperatur, salinitas dan sejumlah parameter lainnya termasuk ketersediaan pakan. Untuk mengetahui pengaruh parameter oseanografi terhadap kelimpahan dan sebaran spasial larva ikan di Laut Sulawesi, telah dilakukan penelitian menggunakan kapal riset KR Baruna Jaya VII pada Oktober 2012. Parameter oseanografi yaitu temperatur dan salinitas diukur menggunakan iCTD dan sampling larva menggunakan bonggo net pada 18 stasiun pengukuran. Analisa hubungan kondisi oseanografi dengan sebaran larva dilakukan secara deskriptif dan pemetaan sebarannya dilakukan secara spasial. Hasil menunjukan keterkaitan sejumlah parameter oseanografi dengan kelimpahan dan sebaran spasial larva ikan. Sebaran larva famili Scombroidae dominan berada pada perairan bersalinitas tinggi karena merupakan jenis ikan oseanik. Larva ikan demersal banyak ditemukan di perairan sekitar Kep.Sangihe Talaud. Kelimpahan larva tertinggi ditemukan di perairan bagian utara dan barat lokasi penelitian dimana kelimpahan plankton tinggi ditemukan.   Celebes Sea is known as a potential fishing and spawning grounds for several pelagic fish species. Abundance and distribution of fish larvae are allegedly linked to oceanographic conditions such as temperature, salinity and others oceanographic parameters including food availablity. To see the effect of oceanographic on the abundance and spatial distribution of fish larvae in the Celebes Sea, has conducted a research in October 2012using the research vessel KR Baruna Jaya VII. The measurement of oceanographic parameters including temperature and salinity and larval sampling were done respectively by using iCTD and Bonggo net at 18 measuring stations. The

  14. Tools for automating the imaging of zebrafish larvae.

    Science.gov (United States)

    Pulak, Rock

    2016-03-01

    The VAST BioImager system is a set of tools developed for zebrafish researchers who require the collection of images from a large number of 2-7 dpf zebrafish larvae. The VAST BioImager automates larval handling, positioning and orientation tasks. Color images at about 10 μm resolution are collected from the on-board camera of the system. If images of greater resolution and detail are required, this system is mounted on an upright microscope, such as a confocal or fluorescence microscope, to utilize their capabilities. The system loads a larvae, positions it in view of the camera, determines orientation using pattern recognition analysis, and then more precisely positions to user-defined orientation for optimal imaging of any desired tissue or organ system. Multiple images of the same larva can be collected. The specific part of each larva and the desired orientation and position is identified by the researcher and an experiment defining the settings and a series of steps can be saved and repeated for imaging of subsequent larvae. The system captures images, then ejects and loads another larva from either a bulk reservoir, a well of a 96 well plate using the LP Sampler, or individually targeted larvae from a Petri dish or other container using the VAST Pipettor. Alternative manual protocols for handling larvae for image collection are tedious and time consuming. The VAST BioImager automates these steps to allow for greater throughput of assays and screens requiring high-content image collection of zebrafish larvae such as might be used in drug discovery and toxicology studies. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

  15. Regional distribution of Paenibacillus larvae subspecies larvae, the causative organism of American foulbrood, in honey bee colonies of the Western United States.

    Science.gov (United States)

    Eischen, Frank A; Graham, R Henry; Cox, Robert

    2005-08-01

    We examined honey bee, Apis mellifera L., colonies pollinating almonds in California during February 2003 for Paenibacillus larvae subsp. Larvae, the causative organism of the virulent brood disease American foulbrood. Colonies originating from the Rocky Mountain area and California had significantly higher numbers (P bees, respectively) than colonies from the upper Midwest (1.28). Colonies from the northwestern, central, and southwestern United States had intermediate CFU or bacterial colony levels. Operations positive for P. larvae larvae were relatively uniform at approximately 70-80%, and no regional significant differences were found. Percentages of colonies with high CFUs (> or = 400 per 30 bees) differed significantly, with those from the Rocky Mountain region having 8.73% compared with those of the upper Midwest with 0%. The significance of CFU levels was evaluated by inoculating healthy colonies with diseased immatures and sampling adult bees. The number of CFUs detected per diseased immature was conservatively estimated to be approximately 399 CFUs per 30 adult bees. We defined this spore level as 1 disease equivalent. Based on this, 3.86% colonies in our survey had 1 or more disease equivalent number of P. larvae larvae CFUs. Operations with high P. larvae larvae spore levels in their colonies will likely observe American foulbrood if prophylaxis is not practiced diligently.

  16. Effect of gamma rays on the larvae of Rhipicephalus bursa

    International Nuclear Information System (INIS)

    Gecheva, G.

    1979-01-01

    Rhipicephalus bursa larvae were exposed to a single acute gamma-irradiation from cobalt 60 source in doses from 0.5 to 40 kiloroentgen (kr). Doses higher than 20 kr rilled the larvae, lower than 10 kr produced disturbances in tick development, dependent on radiation; larvae irradiated with 2 to 3 kr started sucking blood as larvae ordinarily do, but could not undergo metamorphosis; larvae irradiated with lower doses (0.5 and 1 kr) had a prolonged metamorphosis, the onset of oviposition was delayed and the percentage of hatched second generation larvae was reduced. (A.B.)

  17. A Madurella mycetomatis Grain Model in Galleria mellonella Larvae.

    Directory of Open Access Journals (Sweden)

    Wendy Kloezen

    Full Text Available Eumycetoma is a chronic granulomatous subcutaneous infectious disease, endemic in tropical and subtropical regions and most commonly caused by the fungus Madurella mycetomatis. Interestingly, although grain formation is key in mycetoma, its formation process and its susceptibility towards antifungal agents are not well understood. This is because grain formation cannot be induced in vitro; a mammalian host is necessary to induce its formation. Until now, invertebrate hosts were never used to study grain formation in M. mycetomatis. In this study we determined if larvae of the greater wax moth Galleria mellonella could be used to induce grain formation when infected with M. mycetomatis. Three different M. mycetomatis strains were selected and three different inocula for each strain were used to infect G. mellonella larvae, ranging from 0.04 mg/larvae to 4 mg/larvae. Larvae were monitored for 10 days. It appeared that most larvae survived the lowest inoculum, but at the highest inoculum all larvae died within the 10 day observation period. At all inocula tested, grains were formed within 4 hours after infection. The grains produced in the larvae resembled those formed in human and in mammalian hosts. In conclusion, the M. mycetomatis grain model in G. mellonella larvae described here could serve as a useful model to study the grain formation and therapeutic responses towards antifungal agents in the future.

  18. Coral larvae move toward reef sounds

    NARCIS (Netherlands)

    Vermeij, M.J.A.; Marhaver, K.L.; Huijbers, C.M.; Nagelkerken, I.; Simpson, S.D.

    2010-01-01

    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm) that influence settlement success are difficult to

  19. Complete Genome Sequence of Paenibacillus larvae MEX14, Isolated from Honey Bee Larvae from the Xochimilco Quarter in Mexico City.

    Science.gov (United States)

    Peréz de la Rosa, D; Pérez de la Rosa, J J; Cossio-Bayugar, R; Miranda-Miranda, E; Lozano, L; Bravo-Díaz, M A; Rocha-Martínez, M K; Sachman-Ruiz, B

    2015-08-27

    Paenibacillus larvae strain MEX14 is a facultative anaerobic endospore-forming bacterium that infects Apis mellifera larvae. Strain MEX14 was isolated from domestic bee larvae collected in a backyard in Mexico City. The estimated genome size was determined to be 4.18 Mb, and it harbors 4,806 protein coding genes (CDSs). Copyright © 2015 Peréz de la Rosa et al.

  20. Sun-Compass Orientation in Mediterranean Fish Larvae.

    Science.gov (United States)

    Faillettaz, Robin; Blandin, Agathe; Paris, Claire B; Koubbi, Philippe; Irisson, Jean-Olivier

    2015-01-01

    Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history, larvae of coastal species have to head back to the shore at the end of their pelagic episode, to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence of coast-related cues on orientation. In this study we quantified the in situ orientation behavior of settlement-stage larvae in a temperate region, with a continuous coast and a dominant along-shore current, and inspected both coast-dependent and independent cues. We tested six species: one Pomacentridae, Chromis chromis, and five Sparidae, Boops boops, Diplodus annularis, Oblada melanura, Spicara smaris and Spondyliosoma cantharus. Over 85% of larvae were highly capable of keeping a bearing, which is comparable to the orientation abilities of tropical species. Sun-related cues influenced the precision of bearing-keeping at individual level. Three species, out of the four tested in sufficient numbers, oriented significantly relative to the sun position. These are the first in situ observations demonstrating the use of a sun compass for orientation by wild-caught settlement-stage larvae. This mechanism has potential for large-scale orientation of fish larvae globally.

  1. Sun-Compass Orientation in Mediterranean Fish Larvae.

    Directory of Open Access Journals (Sweden)

    Robin Faillettaz

    Full Text Available Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history, larvae of coastal species have to head back to the shore at the end of their pelagic episode, to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence of coast-related cues on orientation. In this study we quantified the in situ orientation behavior of settlement-stage larvae in a temperate region, with a continuous coast and a dominant along-shore current, and inspected both coast-dependent and independent cues. We tested six species: one Pomacentridae, Chromis chromis, and five Sparidae, Boops boops, Diplodus annularis, Oblada melanura, Spicara smaris and Spondyliosoma cantharus. Over 85% of larvae were highly capable of keeping a bearing, which is comparable to the orientation abilities of tropical species. Sun-related cues influenced the precision of bearing-keeping at individual level. Three species, out of the four tested in sufficient numbers, oriented significantly relative to the sun position. These are the first in situ observations demonstrating the use of a sun compass for orientation by wild-caught settlement-stage larvae. This mechanism has potential for large-scale orientation of fish larvae globally.

  2. PERKEMBANGAN AWAL LARVA KERAPU KERTANG (Epinephelus lanceolatus

    Directory of Open Access Journals (Sweden)

    Philip Teguh Imanto

    2016-11-01

    Full Text Available Observasi pada larva kerapu kertang (E. lanceolatus dilaksanakan di Balai Besar Riset Perikanan Budidaya Laut (BBRPBL, Gondol-Bali, untuk mengumpulkan informasi dasar tentang perkembangan awal morfologi larva yang penting untuk menunjang keberhasilan pembenihannya. Larva berasal dari telur hasil pemijahan yang dirangsang dengan hormon (di Taiwan dan ditransportasikan segera setelah menetas (D-0 melalui transportasi udara ke laboratotium pembenihan BBRPBL, Gondol. Pengamatan dilakukan dengan memanfaatkan fasilitas tangki 500 L dengan sistem air resirkulasi. Dari data yang dihimpun diketahui bahwa rata-rata panjang total larva (D-1 2,48 mm; D-8 3,17 mm; dan tumbuh dengan cepat mencapai 10,79 mm pada D-19. Kuning telur larva yang berumur sehari (D-1 rata-rata bervolume 150,3 x 10-4 mm3 dan pada hari ketiga terserap 42,61% dan habis pada hari keempat (D-4. Butir minyak larva D-1 sebesar 41,9 x 10-4 mm3 dan masih tersisa sebesar 0,34 x 10-4 mm3 sampai dengan D-6. Mulut larva diperhitungkan sudah mencapai lebar sebesar 200 μm pada D-2. dan mampu untuk memangsa rotifer sejalan dengan pigmentasi mata yang mulai terjadi pada D-2 dan sempurna pada D-3. Dari analisis pertumbuhan terjadi titik belok (flexion point pada D-8 dan setelah itu terjadi kurva pertumbuhan yang cepat y= 0,6747x-2,5508. Berdasarkan hasil observasi tersebut maka pemberian pakan awal untuk larva kerapu kertang sudah bisa diberikan pada D-2 akhir (sore, pada D-8 komposisi pakan alami sudah harus diubah dengan memberikan pakan yang lebih besar dan bernutrisi tinggi. Observation on early development of E. lanceolatus larvae have been conducted in laboratory condition at Gondol Research Institute for Mariculture (GRIM Bali; the purpose was to gain basic data mainly on the larval development stage to support both larval rearing and aquaculture technique of this species. The larvae from egg were produced by induced spawning technique and transported on D-0 to GRIM. Observation have been

  3. Radiosensitivity of spores of Paenibacillus larvae ssp. larvae in honey

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Wanderley Mendes de [Ministerio da Agricultura, Pecuaria e Abastecimento, Rio de Janeiro, RJ (Brazil). Servico de Inspecao de Produtos de Origem Animal]. E-mail: sipa-rj@agricultura.gov.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito CTEx, Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear]. E-mail: vital@ctex.eb.br; Schuch, Dulce Maria Tocchetto [Ministerio da Agricultura, Pecuaria e Abastecimento, Porto Alegre, RS (Brazil)]. E-mail: micro-lara-rs@agricultura.gov.br

    2007-07-01

    Irradiation, usually used in combination with other conventional methods of conservation, has been proven to be an efficient tool to ensure the safety of many types of foods by destroying pathogenic microorganisms and extending their shelf-lives. This work has investigated the efficacy of gamma irradiation to inactivate spores of the bacterium Paenibacillus larvae that causes the 'American foulbrood', a highly contagious disease still exotic in Brazil that kills bees and contaminates honey, preventing its commercialization and causing great economical losses. In this study, 60 g samples of two types of honey inoculated with 3.5x10{sup 3} spores/mL of that bacterium were irradiated with doses of 0, 5, 7.5, 10, 12.5 and 15 kGy and counted. The analyses indicated a mean reduction of 97.5{+-}0.7% in the number of viable spores exposed to 5 kGy. The application of doses of 7.5 kGy or higher yielded no viable spores above the detection threshold (10/mL). In addition the value of D{sub 10} (3.1{+-}0.3 kGy) was estimated and the logarithm of the population of viable spores of Paenibacillus larvae subsp. larvae was determined as linear and quadratic polynomial functions of the radiation dose. The results indicated that the dose of 10 kGy could be insufficient to assure complete sterilization of honey in some cases while suggesting that 25 kGy would perform such task adequately. (author)

  4. Radiolabeling of infective third-stage larvae of Strongyloides stercoralis by feeding [75Se]selenomethionine-labeled Escherichia coli to first- and second-stage larvae

    International Nuclear Information System (INIS)

    Aikens, L.M.; Schad, G.A.

    1989-01-01

    A technique is described for radiolabeling Strongyloides stercoralis larvae with [ 75 Se]selenomethionine. Cultures of an auxotrophic methionine-dependent stain of Escherichia coli were grown in a medium containing Dulbecco's modified Eagle's medium supplemented with 5% nutrient broth, amino acids, and [ 75 Se]selenomethionine. When the 75 Se-labeled bacterial populations were in the stationary phase of growth, cultures were harvested and the bacteria dispersed on agar plates to serve as food for S. stercoralis larvae. Use of nondividing bacteria is important for successful labeling because the isotope is not diluted by cell division and death of larvae attributable to overgrowth by bacteria is prevented. First-stage S. stercoralis larvae were recovered from feces of infected dogs and reared in humid air at 30 C on agar plates seeded with bacteria. After 7 days, infective third-stage larvae were harvested. The mean specific activity of 6 different batches of larvae ranged from 75 to 330 counts per min/larva with 91.8 +/- 9.5% of the population labeled sufficiently to produce an autoradiographic focus during a practicable, 6-wk period of exposure. Labeled infective larvae penetrated the skin of 10-day-old puppies and migrated to the small intestine, where the developed to adulthood

  5. Alimentação e comportamento de larvas de pacu, Piaractus mesopotamicus (Holmberg, 1887 Feeding and behavior of pacu, Piaractus mesopotamicus (Holmberg, 1887 larvae

    Directory of Open Access Journals (Sweden)

    Eduardo Lopes Beerli

    2004-02-01

    Full Text Available Conduziu-se este trabalho com o objetivo de avaliar o efeito da utilização de dietas naturais e artificiais sobre o desempenho e comportamento de larvas de pacu (Piaractus mesopotamicus, entre o 2º e o 10º dia de vida. Foram utilizadas 30 caixas plásticas, cada uma com 30 litros de água e renovação contínua, onde as larvas foram mantidas durante o período experimental. Cada caixa recebeu 10 larvas por litro, totalizando 300 larvas/caixa. Foram testados 6 tratamentos, cada qual com 5 repetições. Os tratamentos foram: T1-ração, T2-plâncton, T3-artêmia, T4-plâncton + ração, T5-artêmia + ração e T6-artêmia + plâncton. As larvas foram alimentadas 6 vezes ao dia, nos horários de 4, 8, 12, 16, 20 e 24 horas. A temperatura da água foi mantida constante a 27ºC, o oxigênio dissolvido permaneceu na faixa de 6,16 ± 0,34 e o pH, entre 7,16 ± 0,22. Aos 2, 4, 6, 8 e 10 dias de vida, foram coletadas amostras de 30 larvas para determinação do comprimento total e peso. No final do experimento (10º dia, as larvas que receberam artêmia + plâncton (T6 alcançaram os maiores valores de comprimento total (8,35 mm e peso corporal (3518 µg, em relação a todas as outras dietas testadas. As larvas devem permanecer em laboratório por um período de 6 dias após a eclosão, recebendo alimento do terceiro ao sexto dia. A partir do sexto dia, as larvas estão com a vesícula gasosa completamente inflada e apresentam nado contínuo.The objective of this research was to evaluate the effect of natural and artificial diets on the development and behavior of pacu (Piaractus mesopotamicus larvae, between the 2nd and 10th day post hatch. The larvaes were kept in 30L - plastic boxes (n = 30 boxes, in constant flow-through. The larvae density was 10 post-larvae/L (300 larvae/box. Six diets with 4 sampling days (4, 6, 8 and 10 days post-hatch, n = 30 larvae using 5 repetitions were tested. The diets were: T1- commercial feed, T2- plancton, T3

  6. Effect of gamma radiation on the Mediterranean flour moth, Ephestia Kuehniella, mature larvae and acceptability of irradiated larvae by Bracon hebetor females

    International Nuclear Information System (INIS)

    Mansour, M.

    2011-06-01

    Mediterranean flour moth, Ephestia kuehniella, mature 5 t h instar larvae were exposed to gamma radiation dosages ranging from 50-350 Gy at 50 Gy increment and the effects of gamma radiation on pupation, adult emergence and sex ratio were investigated. In addition, effects of irradiation on the rate of development to pupae and adults and the acceptance of irradiated larvae by B. hebetor females were examined. Results showed that the radio-sensitivity of E. kuehniella larvae increased with increasing dose. Pupation was significantly affected at 100 Gy dose, and completely prevented at 350 Gy dose. Adult emergence was only slightly different from pupation; emergence was significantly affected at 100 Gy dose and completely prevented at 300 Gy dose. Irradiation also negatively affected the rate of development of larvae to pupae and adults. While more than 98% of control larvae pupated within 10 days of treatment, this ratio decreased to about 79% in larvae exposed to 50 Gy and less than 4% in larvae exposed to 100 Gy dose. The rate of development to the adult stage was also similarly affected. While 97% of control insects emerged as adults in the 1st 20 days of treatment, this ratio decreased to about 53, 2 and zero percent in larvae exposed to 50, 100 and 150 Gy dose respectively. In addition, irradiation significantly affected male: female ratio; sex ratio was skewed in favor of males, and at 250 Gy dose all emerged moths were males. Furthermore, irradiation had no adverse effect on the degree of acceptance of mature larvae to parasitization; irradiated insects were as acceptable to B. hebetor females as unirradiated ones. (author)

  7. Effect of gamma radiation on the Mediterranean flour moth, Ephestia Kuehniella, mature larvae and acceptability of irradiated larvae by Bracon hebetor female

    International Nuclear Information System (INIS)

    Mansour, M.

    2012-01-01

    Mediterranean flour moth, Ephestia kuehniella, mature 5 t h instar larvae were exposed to gamma radiation dosages ranging from 50-350 Gy at 50 Gy increment and the effects of gamma radiation on pupation, adult emergence and sex ratio were investigated. In addition, effects of irradiation on the rate of development to pupae and adults and the acceptance of irradiated larvae by B. hebetor females were examined. Results showed that the radio-sensitivity of E. kuehniella larvae increased with increasing dose. Pupation was significantly affected at 100 Gy dose, and completely prevented at 350 Gy dose. Adult emergence was only slightly different from pupation; emergence was significantly affected at 100 Gy dose and completely prevented at 300 Gy dose. Irradiation also negatively affected the rate of development of larvae to pupae and adults. While more than 98% of control larvae pupated within 10 days of treatment, this ratio decreased to about 79% in larvae exposed to 50 Gy and less than 4% in larvae exposed to 100 Gy dose. The rate of development to the adult stage was also similarly affected. While 97% of control insects emerged as adults in the 1st 20 days of treatment, this ratio decreased to about 53, 2 and zero percent in larvae exposed to 50, 100 and 150 Gy dose respectively. In addition, irradiation significantly affected male: female ratio; sex ratio was skewed in favor of males, and at 250 Gy dose all emerged moths were males. Furthermore, irradiation had no adverse effect on the degree of acceptance of mature larvae to parasitization; irradiated insects were as acceptable to B. hebetor females as unirradiated ones. (author)

  8. Self-heating by large insect larvae?

    Science.gov (United States)

    Cooley, Nikita L; Emlen, Douglas J; Woods, H Arthur

    2016-12-01

    Do insect larvae ever self-heat significantly from their own metabolic activity and, if so, under what sets of environmental temperatures and across what ranges of body size? We examine these questions using larvae of the Japanese rhinoceros beetle (Trypoxylus dichotomus), chosen for their large size (>20g), simple body plan, and underground lifestyle. Using CO 2 respirometry, we measured larval metabolic rates then converted measured rates of gas exchange into rates of heat production and developed a mathematical model to predict how much steady state body temperatures of underground insects would increase above ambient depending on body size. Collectively, our results suggest that large, extant larvae (20-30g body mass) can self-heat by at most 2°C, and under many common conditions (shallow depths, moister soils) would self-heat by less than 1°C. By extending the model to even larger (hypothetical) body sizes, we show that underground insects with masses >1kg could heat, in warm, dry soils, by 1.5-6°C or more. Additional experiments showed that larval critical thermal maxima (CT max ) were in excess of 43.5°C and that larvae could behaviorally thermoregulate on a thermal gradient bar. Together, these results suggest that large larvae living underground likely regulate their temperatures primarily using behavior; self-heating by metabolism likely contributes little to their heat budgets, at least in most common soil conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Efecto de la temperatura sobre la viabilidad de larvas de Trichinella spiralis Effect of temperature on the viability of Trichinella spiralis larvae

    Directory of Open Access Journals (Sweden)

    Viviana R Randazzo

    2011-12-01

    Full Text Available El objetivo de este estudio fue determinar el efecto de diferentes temperaturas sobre la viabilidad de larvas libres y enquistadas de Trichinella spiralis aisladas en el sudoeste de la provincia de Buenos Aires, Argentina. Se trataron larvas libres y enquistadas a diferentes temperaturas (-30 °C, -20 °C, 4 °C, 20 °C, calentamiento gradual entre 0-100 °C. Se determinó el tiempo necesario para matar el 100 % de las larvas. Durante los primeros días, la mortalidad larvaria en todos los tratamientos con frío aumentó signifcativamente en función del tiempo. En todos los casos, las larvas libres sobrevivieron menor cantidad de días que las enquistadas. A -30 °C, -20 °C y 20 °C no se observaron diferencias signifcativas entre las curvas de mortalidad de cada estadio larvario, pero a 4 °C la mortalidad fue menos intensa entre las larvas enquistadas. El calentamiento disminuyó la viabilidad, sin observarse diferencias entre estadios larvarios. La totalidad de las larvas libres y enquistadas había muerto a los 61 y 95 días (-30 °C, a los 160 y 180 días (-20 °C, a los 280 y 330 días (4° C, y a los 460 y 590 días (20 °C, respectivamente. Fue necesaria una cocción durante 15 minutos a 90 °C para matar al 100 % de las larvas libres y a 100 °C para lograr igual mortalidad de las enquistadas. Nuestros resultados indican que la temperatura y los tiempos tradicionalmente utilizados para tratar productos cárnicos con potencial de transmisión de T. spiralis no serían los más efectivos para lograr la inactivación de la totalidad de larvas vivas de este parásito.The aim of this work was to study the effect of temperature on the viability of free and encysted larvae of Trichinella spiralis from southwest Buenos Aires province, Argentina. Larvae were treated at variable temperatures (-30 °C, -20 °C, 4 °C, 20 °C, gradual heating between 0-100 °C. The time necessary to kill 100 % of larvae was calculated. During the frst days of

  10. Bacteria Present in Comadia redtenbacheri Larvae (Lepidoptera: Cossidae).

    Science.gov (United States)

    Hernández-Flores, L; Llanderal-Cázares, C; Guzmán-Franco, A W; Aranda-Ocampo, S

    2015-09-01

    The external and internal culturable bacterial community present in the larvae of Comadia redtenbacheri Hammerschmidt, an edible insect, was studied. Characterization of the isolates determined the existence of 18 morphotypes and phylogenetic analysis of the 16S rRNA gene revealed the existence of Paenibacillus sp., Bacillus safensis, Pseudomonas sp., Bacillus pseudomycoides, Corynebacterium variabile, Enterococcus sp., Gordonia sp., Acinetobacter calcoaceticus, Arthrobacter sp., Micrococcus sp., and Bacillus cereus. Greater diversity of bacteria was found in those larvae obtained from vendors than in those directly taken from Agave plants in nature. Many of the larvae obtained from vendors presented signs of potential disease, and after the analysis, results showed a greater bacterial community compared with the larvae with a healthy appearance. This indicates that bacterial flora can vary in accordance with how the larvae are handled during extraction, collection, and transport. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Antibacterial properties of grapefruit seed extract against Paenibacillus larvae subsp. larvae.

    Science.gov (United States)

    Semprini, P; Langella, V; Pasini, B; Falda, M T; Calvarese, S

    2004-01-01

    Twenty-one samples of grapefruit seed extract (GSE) either from marketed products or provided by an apiculturist were analysed to verify their inhibition activity, in particular against Paenibacillus larvae subsp. larvae, responsible for American foulbrood. The bactericide capacity of GSE has been measured in Bacillus subtilis BGA, Bacillus cereus 11778, Bacillus cereus K250 and Micrococcus luteus 9341a; these bacteria are normally used in the laboratory to study inhibitors. The results showed that not all GSE have the same inhibitory activity and two of those analysed do not inhibit the five bacteria used. Considering that 19 samples inhibited American foulbrood bacillus, the authors conclude that the use of a natural product (such as GSE) to control this important disease of bees, can be used as a substitute for chemotherapeutic products, after appropriate expedients.

  12. Feeding frequency and caste differentiation in Bombus terrestris larvae

    NARCIS (Netherlands)

    Ribeiro, M.F.; Velthuis, H.H.W.; Duchateau, Marie José; Tweel, I. van der

    1998-01-01

    The frequency with which bumble bee larvae are fed during their development was studied using video-recordings. The behaviour of the workers while feeding worker, male and queen larvae of Bombus terrestris was recorded. At the beginning of development, female larvae of both castes were fed at a

  13. Fish larvae from the Canary region in autumn

    Directory of Open Access Journals (Sweden)

    J. M. Rodríguez

    2000-03-01

    Full Text Available In this paper, the taxonomic composition of the fish larvae community in the Canary region in autumn 1991 is presented. In total, 8699 larvae belonging to 58 fish families were studied. 176 taxonomic groups were identified, 149 at species level and the rest were identified at a higher level. The most numerous family and the one that presented the greatest number of species was Myctophidae. The most frequently caught species was Cyclothone braueri. The taxonomic composition (at family level of the fish larvae community, dominated by four mesopelagic families, was typical of oceanic regions of warm waters. The most remarkable feature of the fish larvae community was its high specific diversity.

  14. Analysis of feeding behavior of Drosophila larvae on liquid food.

    Science.gov (United States)

    Shen, Ping

    2012-05-01

    The food responses of Drosophila larvae offer an excellent opportunity to study the genetic and neural regulation of feeding behavior. Compared with fed larvae, hungry larvae are more likely to display aggressive foraging, rapid food intake, compensatory feeding, and stress-resistant food procurement. Behavioral assays have been developed to quantitatively assess particular aspects of the hunger-driven food response. In combination, these assays help define the specific role of signaling molecules or neurons in the regulation of feeding behavior in foraging larvae. This protocol describes the analysis of larvae feeding on liquid food. The test is designed for quantitative assessment of the food ingestion rate of individual larvae under different energy states. It provides a simple and reliable way to measure the graded modification of the baseline feeding rate of larvae as food deprivation is prolonged. The test is applicable to routine functional testing and larger-scale screening of genetic mutations and biologics that might affect food consumption.

  15. Abscisic acid enhances cold tolerance in honeybee larvae.

    Science.gov (United States)

    Ramirez, Leonor; Negri, Pedro; Sturla, Laura; Guida, Lucrezia; Vigliarolo, Tiziana; Maggi, Matías; Eguaras, Martín; Zocchi, Elena; Lamattina, Lorenzo

    2017-04-12

    The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee ( Apis mellifera ). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro -reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin , and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects. © 2017 The Author(s).

  16. Abscisic acid enhances cold tolerance in honeybee larvae

    Science.gov (United States)

    Sturla, Laura; Guida, Lucrezia; Vigliarolo, Tiziana; Maggi, Matías; Eguaras, Martín; Zocchi, Elena; Lamattina, Lorenzo

    2017-01-01

    The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee (Apis mellifera). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro-reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin, and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects. PMID:28381619

  17. Effect of gut bacterial isolates from Apis mellifera jemenitica on Paenibacillus larvae infected bee larvae.

    Science.gov (United States)

    Al-Ghamdi, Ahmad; Ali Khan, Khalid; Javed Ansari, Mohammad; Almasaudi, Saad B; Al-Kahtani, Saad

    2018-02-01

    The probiotic effects of seven newly isolated gut bacteria, from the indegenous honey bees of Saudi Arabia were investigated. In vivo bioassays were used to investigate the effects of each gut bacterium namely, Fructobacillus fructosus (T1), Proteus mirabilis (T2), Bacillus licheniformis (T3), Lactobacillus kunkeei (T4), Bacillus subtilis (T5), Enterobacter kobei (T6), and Morganella morganii (T7) on mortality percentage of honey bee larvae infected with P. larvae spores along with negative control (normal diet) and positive control (normal diet spiked with P. larvae spores). Addition of gut bacteria to the normal diet significantly reduced the mortality percentage of the treated groups. Mortality percentage in all treated groups ranged from 56.67% up to 86.67%. T6 treated group exhibited the highest mortality (86.67%), whereas T4 group showed the lowest mortality (56.67%). Among the seven gut bacterial treatments, T4 and T3 decreased the mortality 56.67% and 66.67%, respectively, whereas, for T2, T6, and T7 the mortality percentage was equal to that of the positive control (86.67%). Mortality percentages in infected larval groups treated with T1, and T5 were 78.33% and 73.33% respectively. Most of the mortality occurred in the treated larvae during days 2 and 3. Treatments T3 and T4 treatments showed positive effects and reduced mortality.

  18. Workbook on Identification of Aedes Aegypti Larvae.

    Science.gov (United States)

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable yellow fever control workers to identify the larvae of "Aedes aegypti." The morphological features of mosquito larvae are illustrated in this partially programed text, and the distinguishing features of "A. aegypti" indicated. A glossary is included. (AL)

  19. Larvas migrans ganglionar: Presentación de un caso

    Directory of Open Access Journals (Sweden)

    María del Carmen Luis Álvarez

    2003-04-01

    Full Text Available Las larvas migrans visceral cuya causa radica en la infestación con larvas de toxocara canis o cati, ocurre más frecuentemente en niños menores de 10 años. Se presenta el caso de un niño de 8 años de edad en el cual se diagnosticó larvas migrans ganglionar. Se comentan aspectos etioepidemiológicos de la enfermedad, su cuadro clínico y evolución. Se hace énfasis en las medidas higiénicas sanitarias de control y manipulación de excretas de animales domésticos, en este caso de perros y gatos.Visceral larvae migrans caused by the infestation with larvae of toxocara canis or cati are more frequent among children under 10. The case of an 8-year-old boy who was diagnosed ganglionar larva migrans is presented. Comments are made on some etioepidemiological aspects of the disease, as well as on his clinical picture and evolution. Emphasis is made on the hygienic and sanitary measures of control and manipulation of stools from pegs as dogs and cats. Las larvas migrans visceral cuya causa radica en la infestación con larvas de toxocara canis o cati, ocurre más frecuentemente en niños menores de 10 años. Se presenta el caso de un niño de 8 años de edad en el cual se diagnosticó larvas migrans ganglionar. Se comentan aspectos etioepidemiológicos de la enfermedad, su cuadro clínico y evolución. se hace énfasis en las medidas higiénicas sanitarias de control y manipulación de excretas de animales domésticos, en este caso de perros y gatos.

  20. Fish larvae at fronts: Horizontal and vertical distributions of gadoid fish larvae across a frontal zone at the Norwegian Trench

    DEFF Research Database (Denmark)

    Munk, Peter

    2014-01-01

    The reproduction and early life history of many fish species are linked to the physical and biological characteristics of fronts. In order to ascertain linkages between frontal physics and fish larvae, we investigated distributional differences among gadoid fish larvae comparing these to both...... the vertical and horizontal distributions of each species. However, the three-dimensional pattern of distribution differed significantly among species of larvae and species of copepods. The study underlines the complexity of bio-physical interrelationships in the frontal zone, and indicates that the zone...

  1. Effects of the Liquids Used to Kill Larvae on the Length of Forensically Important Blow Fly Lucilia sericata Meigen (Diptera: Calliphoridae Larvae

    Directory of Open Access Journals (Sweden)

    Halide Nihal Açıkgöz

    2017-12-01

    Full Text Available Forensic entomological practices rely upon accurate larval identification and measurement of larval length, for the estimation of post-mortem intervals. The methods used for killing larvae may affect the length of larvae. In the autopsy hall, corpses which are contain entomological remains have been washed with grape vinegar. Besides, while collecting and killing the larvae on corpses, crime scene teams use alcohol 70% because it is practical. The aim of this study was to determine which of hot water (90°C, cold vinegar and cold alcohol 96 % method, preserved the best the length of larvae. To achieve this aim, third instar larvae which are reared on 200 g of veal meat were killed using hot water, cold vinegar and cold alcohol. Before killing and after killing the maggots, their length was measured. To determine the difference between the groups to be compared ANOVA test, to reliability and validity analyses Kruskal-Wallis and whether there was any difference between the groups were made with Tukey’s Honestly Significant Difference (Tukey’s HSD Hot water was found to preserve the length of the larvae more accurately than cold vinegar and alcohol.

  2. Intraguild predation and cannibalism among larvae of detritivorous caddisflies in subalpine wetlands

    Science.gov (United States)

    Wissinger, S.A.; Sparks, G.B.; Rouse, G.L.; Brown, W.S.; Steltzer, Heidi

    1996-01-01

    Comparative data from subalpine wetlands in Colorado indicate that larvae of the limnephilid caddisflies, Asynarchus nigriculus and Limnephilus externus, are reciprocally abundant among habitats - Limnephilus larvae dominate in permanent waters, whereas Asynarchus larvae dominate in temporary basins. The purpose of this paper is to report on field and laboratory experiments that link this pattern of abundance to biotic interactions among larvae. In the first field experiment, growth and survival were compared in single and mixed species treatments in littoral enclosures. Larvae, which eat mainly vascular plant detritus, grew at similar rates among treatments in both temporary and permanent habitats suggesting that exploitative competition is not important under natural food levels and caddisfly densities. However, the survival of Limnephilus larvae was reduced in the presence of Asynarchus larvae. Subsequent behavioral studies in laboratory arenas revealed that Asynarchus larvae are extremely aggressive predators on Limnephilus larvae. In a second field experiment we manipulated the relative sizes of larvae and found that Limnephilus larvae were preyed on only when Asynarchus larvae had the same size advantage observed in natural populations. Our data suggest that the dominance of Asynarchus larvae in temporary habitats is due to asymmetric intraguild predation (IGP) facilitated by a phenological head start in development. These data do not explain the dominance of Limnephilus larvae in permanent basins, which we show elsewhere to be an indirect effect of salamander predation. Behavioral observations also revealed that Asynarchus larvae are cannibalistic. In contrast to the IGP on Limnephilus larvae, Asynarchus cannibalism occurs among same-sized larvae and often involves the mobbing of one victim by several conspecifics. In a third field experiment, we found that Asynarchus cannibalism was not density-dependent and occurred even at low larval densities. We

  3. Dynamics of Social Behavior in Fruit Fly Larvae

    Science.gov (United States)

    Durisko, Zachary; Kemp, Rebecca; Mubasher, Rameeshay; Dukas, Reuven

    2014-01-01

    We quantified the extent and dynamics of social interactions among fruit fly larvae over time. Both a wild-type laboratory population and a recently-caught strain of larvae spontaneously formed social foraging groups. Levels of aggregation initially increased during larval development and then declined with the wandering stage before pupation. We show that larvae aggregated more on hard than soft food, and more at sites where we had previously broken the surface of the food. Groups of larvae initiated burrowing sooner than solitary individuals, indicating that one potential benefit of larval aggregations is an improved ability to dig and burrow into the food substrate. We also show that two closely related species, D. melanogaster and D. simulans, differ in their tendency to aggregate, which may reflect different evolutionary histories. Our protocol for quantifying social behavior in larvae uncovered robust social aggregations in this simple model, which is highly amenable to neurogenetic analyses, and can serve for future research into the mechanisms and evolution of social behavior. PMID:24740198

  4. Mating Success, Longevity, and Fertility of Diabrotica virgifera virgifera LeConte (Chrysomelidae: Coleoptera in Relation to Body Size and Cry3Bb1-Resistant and Cry3Bb1-Susceptible Genotypes

    Directory of Open Access Journals (Sweden)

    Bryan Wade French

    2015-11-01

    Full Text Available Insect resistance to population control methodologies is a widespread problem. The development of effective resistance management programs is often dependent on detailed knowledge regarding the biology of individual species and changes in that biology associated with resistance evolution. This study examined the reproductive behavior and biology of western corn rootworm beetles of known body size from lines resistant and susceptible to the Cry3Bb1 protein toxin expressed in transgenic Bacillus thuringiensis maize. In crosses between, and within, the resistant and susceptible genotypes, no differences occurred in mating frequency, copulation duration, courtship duration, or fertility; however, females mated with resistant males showed reduced longevity. Body size did not vary with genotype. Larger males and females were not more likely to mate than smaller males and females, but larger females laid more eggs. Moderately strong, positive correlation occurred between the body sizes of successfully mated males and females; however, weak correlation also existed for pairs that did not mate. Our study provided only limited evidence for fitness costs associated with the Cry3Bb1-resistant genotype that might reduce the persistence in populations of the resistant genotype but provided additional evidence for size-based, assortative mating, which could favor the persistence of resistant genotypes affecting body size.

  5. Paenilarvins: Iturin family lipopeptides from the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Sood, Sakshi; Steinmetz, Heinrich; Beims, Hannes; Mohr, Kathrin I; Stadler, Marc; Djukic, Marvin; von der Ohe, Werner; Steinert, Michael; Daniel, Rolf; Müller, Rolf

    2014-09-05

    The bacterium Paenibacillus larvae has been extensively studied as it is an appalling honey bee pathogen. In the present work, we screened crude extracts derived from fermentations of P. larvae genotypes ERIC I and II for antimicrobial activity, following the detection of four putative secondary metabolite gene clusters that show high sequence homology to known biosynthetic gene clusters for the biosynthesis of antibiotics. Low molecular weight metabolites produced by P. larvae have recently been shown to have toxic effects on honey bee larvae. Moreover, a novel tripeptide, sevadicin, was recently characterized from laboratory cultures of P. larvae. In this study, paenilarvins, which are iturinic lipopeptides exhibiting strong antifungal activities, were obtained by bioassay-guided fractionation from cultures of P. larvae, genotype ERIC II. Their molecular structures were determined by extensive 2D NMR spectroscopy, high resolution mass spectrometry, and other methods. Paenilarvins are the first antifungal secondary metabolites to be identified from P. larvae. In preliminary experiments, these lipopeptides also affected honey bee larvae and might thus play a role in P. larvae survival and pathogenesis. However, further studies are needed to investigate their function. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Nutritional condition and vertical distribution of Baltic cod larvae

    DEFF Research Database (Denmark)

    Grønkjær, P.; Clemmesen, C.; St. John, Michael

    1997-01-01

    Newly hatched Baltic cod Gadus morhua larvae are typically found at depths >60 m. This is a region of low light and prey availability, hence generating the hypothesis that larvae have to migrate from hatching depth to the surface layer to avoid starvation and improve their nutritional condition...... aged 2-25 days (median 10 days) ranged from 0.4 to 6.2, corresponding to levels exhibited by starving and fast growing larvae in laboratory calibration studies (starvation, protein growth rate, G(pi)=-12.2% day(-1); fast-growing larvae, G(pi)=14.1% day(-1)) respectively. Seventy per cent of the field...

  7. Extreme morphologies of mantis shrimp larvae

    OpenAIRE

    Haug, Carolin; Ahyong, Shane T.; Wiethase, Joris H.; Olesen, Jørgen; Haug, Joachim T.

    2016-01-01

    ABSTRACT Larvae of stomatopods (mantis shrimps) are generally categorized into four larval types: antizoea, pseudozoea (both representing early larval stages), alima and erichthus (the latter two representing later larval stages). These categories, however, do not reflect the existing morphological diversity of stomatopod larvae, which is largely unstudied. We describe here four previously unknown larval types with extreme morphologies. All specimens were found in the collections of the Zoolo...

  8. Effect of gut bacterial isolates from Apis mellifera jemenitica on Paenibacillus larvae infected bee larvae

    Directory of Open Access Journals (Sweden)

    Ahmad Al-Ghamdi

    2018-02-01

    Full Text Available The probiotic effects of seven newly isolated gut bacteria, from the indegenous honey bees of Saudi Arabia were investigated. In vivo bioassays were used to investigate the effects of each gut bacterium namely, Fructobacillus fructosus (T1, Proteus mirabilis (T2, Bacillus licheniformis (T3, Lactobacillus kunkeei (T4, Bacillus subtilis (T5, Enterobacter kobei (T6, and Morganella morganii (T7 on mortality percentage of honey bee larvae infected with P. larvae spores along with negative control (normal diet and positive control (normal diet spiked with P. larvae spores. Addition of gut bacteria to the normal diet significantly reduced the mortality percentage of the treated groups. Mortality percentage in all treated groups ranged from 56.67% up to 86.67%. T6 treated group exhibited the highest mortality (86.67%, whereas T4 group showed the lowest mortality (56.67%. Among the seven gut bacterial treatments, T4 and T3 decreased the mortality 56.67% and 66.67%, respectively, whereas, for T2, T6, and T7 the mortality percentage was equal to that of the positive control (86.67%. Mortality percentages in infected larval groups treated with T1, and T5 were 78.33% and 73.33% respectively. Most of the mortality occurred in the treated larvae during days 2 and 3. Treatments T3 and T4 treatments showed positive effects and reduced mortality.

  9. Development of Digestive Enzyme of Patin Pangasius hypohthalmus Larvae

    Directory of Open Access Journals (Sweden)

    I. Effendi

    2007-01-01

    Full Text Available Culture of patin Pangasius hypophthalmus especially larval rearing  very depends on the supply of natural food as energy source.  Artemia is the main natural food for fish larvae as a starter food, but its price is high.  To reduce production cost, farmers tend to reduce the feeding frequency and shorten  the Artemia feeding period.  Altering feeding regime however may reduce fry quality. This relate to the availability of digestive enzymes.  The objective of this study was  to examine digestive enzymes activity in patin larvae fed with  different feeding regime.  By shorten feeding period with Artemia to 2-4 days and Tubifex,substitution, the enzymes activity of protease, lipase and amylase were revealed similar pattern   The enzymes activity tends to increase and reach the peak at day 7 , and decrease later on until day 15 after hatching.  Survival rate of fish were varied for each treatment, and the highest survival rate was obtained when larvae were fed by Artemia for 8 days.  Blood worm were not fully digested by patin larvae at early stage. Keywords: enzyme, digestion, patin, Pangasius hypophthalmus   ABSTRAK Proses budidaya ikan patin, Pangasius hypophthalmus terutama pembenihan sangat tergantung oleh ketersediaan pakan alami sebagai sumber energinya. Artemia merupakan pakan alami yang banyak diberikan pada saat larva ikan mulai makan, namun harganya relatif tinggi. Untuk menekan biaya produksi, petani ikan patin cenderung mengurangi frekuensi pemberian Artemia dan mempersingkat waktu pemberiannya. Penggeseran jadwal ini diduga mengakibatkan penurunan kualitas benih ikan patin yang dihasilkan yang berhubungan dengan kesiapan enzim pencernaannya. Penelitian ini dilakukan untuk mengetahui aktivitas enzim pada larva ikan patin dengan jadwal pemberian pakan yang berbeda. Dengan memotong waktu pemberian Artemia 2 - 4 hari dan disubstitusi dengan Tubifex, aktifitas enzim protease, lipase dan amilase pada larva ikan patin, memiliki

  10. Nonsensical choices? Fall armyworm moths choose seemingly best or worst hosts for their larvae, but neonate larvae make their own choices.

    Directory of Open Access Journals (Sweden)

    Julio C Rojas

    Full Text Available Selecting optimal host plants is critical for herbivorous insects, such as fall armyworm (Spodoptera frugiperda, an important maize pest in the Americas and Africa. Fall armyworm larvae are presumed to have limited mobility, hence female moths are presumed to be largely responsible for selecting hosts. We addressed host selection by fall armyworm moths and neonate and older (3rd-instar larvae, as mediated by resistance and herbivory in maize plants. Thus, we compared discrimination among three maize cultivars with varying degrees of resistance to fall armyworm, and between plants subjected or not to two types of herbivory. The cultivars were: (i susceptible, and deficient in jasmonic acid (JA production and green leaf volatiles (GLV emissions (inbred line B73-lox10; (ii modestly resistant (B73, and; (iii highly resistant (Mp708. The herbivory types were: (i ongoing (= fall armyworm larvae present, and; (ii future (= fall armyworm eggs present. In choice tests, moths laid more eggs on the highly resistant cultivar, and least on the susceptible cultivar, though on those cultivars larvae performed poorest and best, respectively. In the context of herbivory, moths laid more eggs: (i on plants subject to versus free of future herbivory, regardless of whether plants were deficient or not in JA and GLV production; (ii on plants subject versus free of ongoing herbivory, and; (iii on plants not deficient in compared to deficient in JA and GLV production. Neonate larvae dispersed aerially from host plants (i.e. ballooned, and most larvae colonized the modestly resistant cultivar, and fewest the highly resistant cultivar, suggesting quasi-directional, directed aerial descent. Finally, dispersing older larvae did not discriminate among the three maize cultivars, nor between maize plants and (plastic model maize plants, suggesting random, visually-oriented dispersal. Our results were used to assemble a model of host selection by fall armyworm moths and

  11. Suppressing bullfrog larvae with carbon dioxide

    Science.gov (United States)

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  12. [Toxicity and influencing factors of liquid chlorine on chironomid larvae].

    Science.gov (United States)

    Sun, Xing-Bin; Cui, Fu-Yi; Zhang, Jin-Song; Guo, Zhao-Hai; Xu, Feng; Liu, Li-Jun

    2005-09-01

    The excessive propagation of Chironomid larvae (red worm) in the sedimentation tanks is a difficult problem for the normal function of waterworks. The toxic effect of liquid chlorine on the different instar larvae of Chironomid was studied using distilled water as test sample. Furthermore, the effect of pH value, organic matter content, ammonia nitrogen, and algae content on toxicity of liquid chlorine was observed. The results show that the tolerance of Chironomid larvae to liquid chlorine is strengthened with the increase in instar. The 24h semi-lethal concentration (LC50) of liquid chlorine to the 4th instar larvae of Chironomid is 3.39 mg/L. Low pH value and high algae content are helpful to improve the toxic effect of liquid chlorine to Chironomid larvae. In neutral water body, the increase in organic matter content results in the decrease in the death rate of Chironomid larvae. The toxicity of liquid chlorine differs greatly in different concentrations of ammonia nitrogen. The death rate of the 4th instar larvae of Chironomid in raw water is higher by contrast with that in sedimentation tanks water for 24h disposal with various amount of liquid chlorine.

  13. Bothid larvae (Pleuronectiformes-Pisces) of the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    the Indian Ocean, their regional, seasonal as well as diurnal variations. Engyprosopon grandisquamis dominated contributing to 23.2% of the total larvae. Numerically the incidence of bothid larvae suggested a uniform pattern of distribution during the two...

  14. Analysis of feeding behavior of Drosophila larvae on solid food.

    Science.gov (United States)

    Shen, Ping

    2012-05-01

    The food responses of Drosophila larvae offer an excellent opportunity to study the genetic and neural regulation of feeding behavior. Compared with fed larvae, hungry larvae are more likely to display aggressive foraging, rapid food intake, compensatory feeding, and stress-resistant food procurement. Behavioral assays have been developed to quantitatively assess particular aspects of the hunger-driven food response. In combination, these assays help define the specific role of signaling molecules or neurons in the regulation of feeding behavior in foraging larvae. This protocol is designed for quantitative assessment of the willingness of individual larvae to procure solid food under different energy states. It provides a simple and reliable way to measure the graded modification of the baseline feeding rate of larvae as the period of food deprivation is increased. The test is applicable to routine functional testing and larger-scale screening of genetic mutations and biologics that might affect food consumption.

  15. Manejo de Diabrotica speciosa com atrativos naturais em horta orgânica Natural attractios for management of Diabrotica speciosa in a organic home garden

    Directory of Open Access Journals (Sweden)

    João José Stüpp

    2006-12-01

    Full Text Available O controle de insetos associados ao cultivo de hortaliças é predominantemente realizado através de pesticidas sintéticos. Entretanto, os riscos do uso indiscriminado dos pesticidas sobre a saúde humana e o meio ambiente deve ser considerado. O objetivo deste trabalho foi estudar a eficácia de atrativos naturais no controle da vaquinha Diabrotica speciosa (Germar (Coleoptera: Chrysomelidae, uma praga de importância econômica na América Latina. Os seguintes tratamentos foram testados: raiz de taiuiá (Cayaponia sp, frutos verdes de porongo/cuia (Lagenaria sp, extrato de folhas de couve-chinesa (Brassica pekinensis, fermentado de frutas, vinagre tinto e água como testemunha. O delineamento foi inteiramente ao acaso, com seis repetições. Os preparados foram acondicionados em armadilhas com garrafas PET de 2.000 ml, com oito aberturas laterais e distribuídas aleatoriamente na área experimental. Frutos verdes de porongo apresentaram captura de adultos de D. speciosa 5,4 vezes maior que raízes de taiuiá e as raízes de taiuiá capturaram 19,7 vezes mais adultos do que a testemunha. Ambas as iscas foram acondicionadas na forma sólida, suspensas internamente na garrafa PET. A menor atratividade foi apresentada pelo extrato aquoso de couve-chinesa, que não diferiu da testemunha. Independentemente do atrativo utilizado, o pico populacional da D. speciosa ocorreu nos meses de fevereiro e março.The control of insects associated with home garden vegetable crops is usually done by sintetic pesticides. However, the risks of the indiscriminate use of pesticides on human health and the environment need to be considered. The objective of this work was to study the attractive efficacy of natural substances on D. speciosa, a very important pest in Latin America. The following treatments were tested: roots of Cayaponia sp., green fruits of Lagenaria sp., water extract of Brassica pekinensis, extract of fermented fruits, red vinegar and water as a

  16. External Ophthalmomyiasis Caused by a Rare Infesting Larva, Sarcophaga argyrostoma

    Directory of Open Access Journals (Sweden)

    Shmuel Graffi

    2013-01-01

    Full Text Available Purpose. External ophthalmomyiasis (EO is caused by infesting larvae belonging to various species of flies. Most documented cases result from sheep (Oestrus ovis and Russian (Rhinoestrus purpureus botfly larvae, but we recently discovered a rare case of EO caused by flesh fly (Sarcophaga argyrostoma larvae. Here, we report the case of a patient with EO who had been hospitalized and sedated for 1 week because of unrelated pneumonia. Methods. Case report. Results. A total of 32 larvae were removed from the adnexae of both eyes. Larvae identification was confirmed through DNA analysis. Treatment with topical tobramycin resulted in complete resolution of EO. Conclusion. EO can be caused by S. argyrostoma, and the elderly and debilitated may require extra ocular protection against flies during sedation.

  17. Decapod larvae from the nearshore waters of Karwar

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Paulinose, V.T.

    Abundance of decapod larvae at three stations in Binge Bay, Karwar has been reported based on surface collections taken during the period October 1975 to September 1976. The larvae were very common in the Bay and the postmonsoon months sustained...

  18. Effects of the Liquids Used to Kill Larvae on the Length of Forensically Important Blow Fly Lucilia sericata Meigen (Diptera: Calliphoridae) Larvae

    OpenAIRE

    Halide Nihal Açıkgöz; Ali Açıkgöz

    2017-01-01

    Forensic entomological practices rely upon accurate larval identification and measurement of larval length, for the estimation of post-mortem intervals. The methods used for killing larvae may affect the length of larvae. In the autopsy hall, corpses which are contain entomological remains have been washed with grape vinegar. Besides, while collecting and killing the larvae on corpses, crime scene teams use alcohol 70% because it is practical. The aim of this study was to determine which...

  19. Mananoligossacarídeo em dietas para larvas de tilápia Mannanoligosaccharides in diets for tilapia larvae

    Directory of Open Access Journals (Sweden)

    Kátia Kalko Schwarz

    2011-12-01

    Full Text Available Este experimento foi realizado para avaliar níveis crescentes de mananoligossacarídeo (MOS na dieta de larvas de tilápias-do-nilo (linhagem Supreme® na fase de reversão sexual durante 30 dias. Larvas de tilápia-do-nilo (n=1500, P=0,01 g ± 0,001 g foram distribuídas aleatoriamente em 30 tanques de 100 litros. Os peixes foram distribuídos em delineamento inteiramente casualizado, composto por seis tratamentos e cinco repetições. A dieta controle (isenta de MOS foi elaborada para conter aproximadamente 35% de proteína bruta e 3.100 kcal de ED/kg. As demais foram suplementadas com 0; 0,15; 0,30; 0,45; 0,60 e 0,75% de MOS em substituição ao milho da dieta controle. Com o aumento nos níveis de MOS nas dietas, foi observado aumento linear sobre o comprimento do intestino, a altura das vilosidades intestinais e a densidade dos vilos. Não houve diferença na composição corporal, no ganho em peso, no peso final, no comprimento final, no fator de condição, na taxa de sobrevivência e no número de células caliciformes do intestino das larvas. Os níveis de MOS tiveram efeito quadrático sobre a conversão alimentar, cujos melhores resultados foram obtidos com 0,34% de MOS. A utilização de MOS no nível de 0,34% em dietas para larvas de tilápia-do-nilo melhora a conversão alimentar e promove aumento do comprimento do intestino, da altura das vilosidades e da densidade de vilos intestinal.This experiment was conducted to evaluate increasing levels of mannanoligosaccharides (MOS in the diet of Nile tilapia larvae (Supreme® at the sex reversal stage for 30 days. Nile tilapia larvae (n = 1500, p = 0.01 ± 0.001 g, were randomly distributed in 30 tanks of 100 liters each, for 30 days. The fish were distributed in a randomized design with six treatments and five replicates. The control diet (no MOS was elaborated to contain approximately 35% of crude protein and 3,100 kcal DE/kg. Mannanoligosaccharides were included in the other diets

  20. Using Real-time PCR for Identification of Paenibacillus larvae

    Directory of Open Access Journals (Sweden)

    Vladimíra Kňazovická

    2011-05-01

    Full Text Available The aim of the study was identification of Paenibacillus larvae that causes American foulbrood disease (AFB in colony of bees (Apis mellifera. Bacterial isolates originated from honey samples, because presence of P. larvae in honey is treated as early diagnostic of AFB. Intense proteolytic activity and no catalase activity are typical for Gram positive rod-shaped bacteria P. larvae. We diluted honey (1:2, heated at 80 °C for 10 min and inoculated on semiselective medium MYPGP agar with nalidixic acid. Plates were cultivated at 37 °C for 48 – 72 h under the aerobic conditions. Selected colonies were transferred on MYT agar and cultivated 24 h. We analysed 30 honey samples and found 27 bacterial isolates. All isolates were Gram positive and mainly rod-shaped. No catalase activity was documented for 6 from 27 isolates. Identification was finished by real-time PCR to detect the 16S rRNA gene of Paenibacillus larvae with real-time cycler Rotor-Gene 6000. As DNA template we used genomic DNA isolated with commercial kit and DNA lysate obtaining by boiled cells. We used 2 strains of P. larvae from CCM (Czech Collection of Microorganisms as positive control. The reliable method of detection P. larvae has important rule for beekeeping.

  1. Structure and occurrence of cyphonautes larvae (Bryozoa, Ectoprocta)

    DEFF Research Database (Denmark)

    Nielsen, Claus; Worsaae, Katrine

    2010-01-01

    We have studied larvae of the freshwater ctenostome Hislopia malayensis with scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and LM of serial sections. Some additional observations on larvae of M. membranacea using SEM and CLSM are also reported. The overall configu...

  2. The method by which Cephenemyia trompe (Modeer larvae invade reindeer (Rangifer tarandus

    Directory of Open Access Journals (Sweden)

    John R. Anderson

    1990-09-01

    Full Text Available Laboratory electrostimulated C. trompe (Modeer females forcefully expelled (sprayed larvae for 5-20 cm. The watery spray consisted of about 20 tiny droplets containing two to several larvae. Crawling first-instar larvae exhibited negative geotactic and phototropic responses; they were subject to rapid desiccation and became immobile as the tiny droplets dried within a few seconds. When 5-50 larvae from dissectedfemales were dropped in physiological saline onto different areas of the muzzle of restrained reindeer, only larvae placed deep within the nostrils and on the lips crawled out-of-sight down the nostril passage or into the mouth. Drops of larvae placed elsewhere quickly desiccated and the larvae became immobile. Larvae deposited by wild females onto a COz-baited reindeer model with the muzzle, lips and nostrils coated with insect trapping adhesive all were stuck only along the dorsal lip below the philtrum. All experimental evidence supports a natural per os mode of invasion.

  3. Parasites of fish larvae: do they follow metabolic energetic laws?

    Science.gov (United States)

    Muñoz, Gabriela; Landaeta, Mauricio F; Palacios-Fuentes, Pamela; George-Nascimento, Mario

    2015-11-01

    Eumetazoan parasites in fish larvae normally exhibit large body sizes relative to their hosts. This observation raises a question about the potential effects that parasites might have on small fish. We indirectly evaluated this question using energetic metabolic laws based on body volume and the parasite densities. We compared the biovolume as well as the numeric and volumetric densities of parasites over the host body volume of larval and juvenile-adult fish and the average of these parasitological descriptors for castrator parasites and the parasites found in the fish studied here. We collected 5266 fish larvae using nearshore zooplankton sampling and 1556 juveniles and adult fish from intertidal rocky pools in central Chile. We considered only the parasitized hosts: 482 fish larvae and 629 juvenile-adult fish. We obtained 31 fish species; 14 species were in both plankton and intertidal zones. Fish larvae exhibited a significantly smaller biovolume but larger numeric and volumetric densities of parasites than juvenile-adult fish. Therefore, fish larvae showed a large proportion of parasite biovolume per unit of body host (cm(3)). However, the general scaling of parasitological descriptors and host body volume were similar between larvae and juvenile-adult fish. The ratio between the biovolume of parasites and the host body volume in fish larvae was similar to the proportion observed in castrator parasites. Furthermore, the ratios were different from those of juvenile-adult fish, which suggests that the presence of parasites implies a high energetic cost for fish larvae that would diminish the fitness of these small hosts.

  4. The larva of Paracapnia disala (Jewett) (Plecoptera: Capniidae)

    Science.gov (United States)

    Kenneth W. Stewart

    2010-01-01

    The larva of Paracapnia disala (Jewett) was associated from two first order headwater streams in the H.J. Andrews Experimental Forest, Oregon, U.S.A. Larvae of this first western Paracapnia species to be associated, were studied and compared morphologically with those of the eastern Paracapnia angulata...

  5. Composition, Abundance and Distribution of Brachyuran Larvae in ...

    African Journals Online (AJOL)

    ... Ocypodidae, Grapsidae and Xanthidae. Abundance of brachyuran larvae was significantly positively correlated with total zooplankton abundance (r2 = 0.8) and salinity (r2 = 0.71). Keywords: Brachyuran larvae, abundance, composition, Mida creek, Kenya West Indian Ocean Journal of Marine Science Vol. 3 (2) 2004: pp.

  6. How to kill the honey bee larva: genomic potential and virulence mechanisms of Paenibacillus larvae.

    Directory of Open Access Journals (Sweden)

    Marvin Djukic

    Full Text Available Paenibacillus larvae, a Gram positive bacterial pathogen, causes American Foulbrood (AFB, which is the most serious infectious disease of honey bees. In order to investigate the genomic potential of P. larvae, two strains belonging to two different genotypes were sequenced and used for comparative genome analysis. The complete genome sequence of P. larvae strain DSM 25430 (genotype ERIC II consisted of 4,056,006 bp and harbored 3,928 predicted protein-encoding genes. The draft genome sequence of P. larvae strain DSM 25719 (genotype ERIC I comprised 4,579,589 bp and contained 4,868 protein-encoding genes. Both strains harbored a 9.7 kb plasmid and encoded a large number of virulence-associated proteins such as toxins and collagenases. In addition, genes encoding large multimodular enzymes producing nonribosomally peptides or polyketides were identified. In the genome of strain DSM 25719 seven toxin associated loci were identified and analyzed. Five of them encoded putatively functional toxins. The genome of strain DSM 25430 harbored several toxin loci that showed similarity to corresponding loci in the genome of strain DSM 25719, but were non-functional due to point mutations or disruption by transposases. Although both strains cause AFB, significant differences between the genomes were observed including genome size, number and composition of transposases, insertion elements, predicted phage regions, and strain-specific island-like regions. Transposases, integrases and recombinases are important drivers for genome plasticity. A total of 390 and 273 mobile elements were found in strain DSM 25430 and strain DSM 25719, respectively. Comparative genomics of both strains revealed acquisition of virulence factors by horizontal gene transfer and provided insights into evolution and pathogenicity.

  7. How to kill the honey bee larva: genomic potential and virulence mechanisms of Paenibacillus larvae.

    Science.gov (United States)

    Djukic, Marvin; Brzuszkiewicz, Elzbieta; Fünfhaus, Anne; Voss, Jörn; Gollnow, Kathleen; Poppinga, Lena; Liesegang, Heiko; Garcia-Gonzalez, Eva; Genersch, Elke; Daniel, Rolf

    2014-01-01

    Paenibacillus larvae, a Gram positive bacterial pathogen, causes American Foulbrood (AFB), which is the most serious infectious disease of honey bees. In order to investigate the genomic potential of P. larvae, two strains belonging to two different genotypes were sequenced and used for comparative genome analysis. The complete genome sequence of P. larvae strain DSM 25430 (genotype ERIC II) consisted of 4,056,006 bp and harbored 3,928 predicted protein-encoding genes. The draft genome sequence of P. larvae strain DSM 25719 (genotype ERIC I) comprised 4,579,589 bp and contained 4,868 protein-encoding genes. Both strains harbored a 9.7 kb plasmid and encoded a large number of virulence-associated proteins such as toxins and collagenases. In addition, genes encoding large multimodular enzymes producing nonribosomally peptides or polyketides were identified. In the genome of strain DSM 25719 seven toxin associated loci were identified and analyzed. Five of them encoded putatively functional toxins. The genome of strain DSM 25430 harbored several toxin loci that showed similarity to corresponding loci in the genome of strain DSM 25719, but were non-functional due to point mutations or disruption by transposases. Although both strains cause AFB, significant differences between the genomes were observed including genome size, number and composition of transposases, insertion elements, predicted phage regions, and strain-specific island-like regions. Transposases, integrases and recombinases are important drivers for genome plasticity. A total of 390 and 273 mobile elements were found in strain DSM 25430 and strain DSM 25719, respectively. Comparative genomics of both strains revealed acquisition of virulence factors by horizontal gene transfer and provided insights into evolution and pathogenicity.

  8. Chironomidae bloodworms larvae as aquatic amphibian food.

    Science.gov (United States)

    Fard, Mojdeh Sharifian; Pasmans, Frank; Adriaensen, Connie; Laing, Gijs Du; Janssens, Geert Paul Jules; Martel, An

    2014-01-01

    Different species of chironomids larvae (Diptera: Chironomidae) so-called bloodworms are widely distributed in the sediments of all types of freshwater habitats and considered as an important food source for amphibians. In our study, three species of Chironomidae (Baeotendipes noctivagus, Benthalia dissidens, and Chironomus riparius) were identified in 23 samples of larvae from Belgium, Poland, Russia, and Ukraine provided by a distributor in Belgium. We evaluated the suitability of these samples as amphibian food based on four different aspects: the likelihood of amphibian pathogens spreading, risk of heavy metal accumulation in amphibians, nutritive value, and risk of spreading of zoonotic bacteria (Salmonella, Campylobacter, and ESBL producing Enterobacteriaceae). We found neither zoonotic bacteria nor the amphibian pathogens Ranavirus and Batrachochytrium dendrobatidis in these samples. Our data showed that among the five heavy metals tested (Hg, Cu, Cd, Pb, and Zn), the excess level of Pb in two samples and low content of Zn in four samples implicated potential risk of Pb accumulation and Zn inadequacy. Proximate nutritional analysis revealed that, chironomidae larvae are consistently high in protein but more variable in lipid content. Accordingly, variations in the lipid: protein ratio can affect the amount and pathway of energy supply to the amphibians. Our study indicated although environmentally-collected chironomids larvae may not be vectors of specific pathogens, they can be associated with nutritional imbalances and may also result in Pb bioaccumulation and Zn inadequacy in amphibians. Chironomidae larvae may thus not be recommended as single diet item for amphibians. © 2014 Wiley Periodicals, Inc.

  9. Quantification of vestibular-induced eye movements in zebrafish larvae

    Directory of Open Access Journals (Sweden)

    Mo Weike

    2010-09-01

    Full Text Available Abstract Background Vestibular reflexes coordinate movements or sensory input with changes in body or head position. Vestibular-evoked responses that involve the extraocular muscles include the vestibulo-ocular reflex (VOR, a compensatory eye movement to stabilize retinal images. Although an angular VOR attributable to semicircular canal stimulation was reported to be absent in free-swimming zebrafish larvae, recent studies reveal that vestibular-induced eye movements can be evoked in zebrafish larvae by both static tilts and dynamic rotations that tilt the head with respect to gravity. Results We have determined herein the basis of sensitivity of the larval eye movements with respect to vestibular stimulus, developmental stage, and sensory receptors of the inner ear. For our experiments, video recordings of larvae rotated sinusoidally at 0.25 Hz were analyzed to quantitate eye movements under infrared illumination. We observed a robust response that appeared as early as 72 hours post fertilization (hpf, which increased in amplitude over time. Unlike rotation about an earth horizontal axis, rotation about an earth vertical axis at 0.25 Hz did not evoke eye movements. Moreover, vestibular-induced responses were absent in mutant cdh23 larvae and larvae lacking anterior otoliths. Conclusions Our results provide evidence for a functional vestibulo-oculomotor circuit in 72 hpf zebrafish larvae that relies upon sensory input from anterior/utricular otolith organs.

  10. CalCOFI Larvae Counts, Scientific Names CI to CO

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  11. CalCOFI Larvae Counts, Scientific Names DH to EC

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  12. CalCOFI Larvae Counts, Scientific Names TF to U

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  13. CalCOFI Larvae Counts, Scientific Names HJ to ID

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  14. CalCOFI Larvae Counts, Scientific Names AN to AR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  15. CalCOFI Larvae Counts, Scientific Names SJ to ST

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  16. CalCOFI Larvae Counts, Scientific Names CP to DE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  17. CalCOFI Larvae Counts, Scientific Names C to CE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  18. CalCOFI Larvae Counts, Scientific Names EV to GN

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  19. CalCOFI Larvae Counts, Scientific Names V to Z

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  20. CalCOFI Larvae Counts, Scientific Names ED to EU

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  1. CalCOFI Larvae Counts, Scientific Names SD to SI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  2. CalCOFI Larvae Counts, Scientific Names MB to MO

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  3. CalCOFI Larvae Counts, Scientific Names LJ to MA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  4. CalCOFI Larvae Counts, Scientific Names AS to BA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  5. CalCOFI Larvae Counts, Scientific Names SB to SC

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  6. CalCOFI Larvae Counts, Scientific Names MP to NA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  7. CalCOFI Larvae Counts, Scientific Names SU to TE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  8. CalCOFI Larvae Counts, Scientific Names PL to PO

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  9. CalCOFI Larvae Counts, Scientific Names IE to LA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  10. CalCOFI Larvae Counts, Scientific Names A to AM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  11. CalCOFI Larvae Counts, Scientific Names HB to HI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  12. CalCOFI Larvae Counts, Scientific Names OM to OX

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  13. CalCOFI Larvae Counts, Scientific Names Q to SA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  14. CalCOFI Larvae Counts, Scientific Names PP to PZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  15. CalCOFI Larvae Counts, Scientific Names GO to HA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  16. CalCOFI Larvae Counts, Scientific Names NB to OL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  17. CalCOFI Larvae Counts, Scientific Names LB to LI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  18. CalCOFI Larvae Counts, Scientific Names BCE to BZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  19. CalCOFI Larvae Counts, Scientific Names CD to CH

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  20. CalCOFI Larvae Counts, Scientific Names OY to PI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  1. The use of fly larvae for organic waste treatment.

    Science.gov (United States)

    Čičková, Helena; Newton, G Larry; Lacy, R Curt; Kozánek, Milan

    2015-01-01

    The idea of using fly larvae for processing of organic waste was proposed almost 100 years ago. Since then, numerous laboratory studies have shown that several fly species are well suited for biodegradation of organic waste, with the house fly (Musca domestica L.) and the black soldier fly (Hermetia illucens L.) being the most extensively studied insects for this purpose. House fly larvae develop well in manure of animals fed a mixed diet, while black soldier fly larvae accept a greater variety of decaying organic matter. Blow fly and flesh fly maggots are better suited for biodegradation of meat processing waste. The larvae of these insects have been successfully used to reduce mass of animal manure, fecal sludge, municipal waste, food scrapes, restaurant and market waste, as well as plant residues left after oil extraction. Higher yields of larvae are produced on nutrient-rich wastes (meat processing waste, food waste) than on manure or plant residues. Larvae may be used as animal feed or for production of secondary products (biodiesel, biologically active substances). Waste residue becomes valuable fertilizer. During biodegradation the temperature of the substrate rises, pH changes from neutral to alkaline, ammonia release increases, and moisture decreases. Microbial load of some pathogens can be substantially reduced. Both larvae and digested residue may require further treatment to eliminate pathogens. Facilities utilizing natural fly populations, as well as pilot and full-scale plants with laboratory-reared fly populations have been shown to be effective and economically feasible. The major obstacles associated with the production of fly larvae from organic waste on an industrial scale seem to be technological aspects of scaling-up the production capacity, insufficient knowledge of fly biology necessary to produce large amounts of eggs, and current legislation. Technological innovations could greatly improve performance of the biodegradation facilities and

  2. Crustacean Larvae-Vision in the Plankton.

    Science.gov (United States)

    Cronin, Thomas W; Bok, Michael J; Lin, Chan

    2017-11-01

    We review the visual systems of crustacean larvae, concentrating on the compound eyes of decapod and stomatopod larvae as well as the functional and behavioral aspects of their vision. Larval compound eyes of these macrurans are all built on fundamentally the same optical plan, the transparent apposition eye, which is eminently suitable for modification into the abundantly diverse optical systems of the adults. Many of these eyes contain a layer of reflective structures overlying the retina that produces a counterilluminating eyeshine, so they are unique in being camouflaged both by their transparency and by their reflection of light spectrally similar to background light to conceal the opaque retina. Besides the pair of compound eyes, at least some crustacean larvae have a non-imaging photoreceptor system based on a naupliar eye and possibly other frontal eyes. Larval compound-eye photoreceptors send axons to a large and well-developed optic lobe consisting of a series of neuropils that are similar to those of adult crustaceans and insects, implying sophisticated analysis of visual stimuli. The visual system fosters a number of advanced and flexible behaviors that permit crustacean larvae to survive extended periods in the plankton and allows them to reach acceptable adult habitats, within which to metamorphose. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  3. Observations of the sound producing organs in achelate lobster larvae

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2017-06-01

    Full Text Available The Achelata, lobsters lacking claws and having a phyllosoma larva, are divided into two families, the Palinuridae or spiny lobsters and the Scyllaridae or slipper lobsters. Within the Palinuridae adults of two groups were identified by Parker (1884, the Stridentesthat are capable of producing sounds, and the Silentesthat are not known to produce sounds. The Stridentes employ a file-like structure on the dorsal surface of the cephalon and a plectrum consisting of a series of ridges on the proximal segment of the second antenna to produce their sounds. All species of Achelata hatch as an unpigmented thin phyllosoma larva. The phyllosoma larva of the Stridentes have a presumptive file-like structure on the dorsal cephalon. A similar file-like structure is found on the cephalon of one species of Silentes, Palinurellus wienckki, and some but not all of the phyllosoma larvae of the Scyllaridae. No presumptive plectrum is found on the second antenna of any of the phyllosoma larvae. Presence of a presumptive file-like structure on phyllosoma larvae of Silentes and Scyllaridae suggests that the ability to produce sounds may have been lost secondarily in the Silentes and Scyllaridae.

  4. Identification of tissue-embedded ascarid larvae by ribosomal DNA sequencing.

    Science.gov (United States)

    Ishiwata, Kenji; Shinohara, Akio; Yagi, Kinpei; Horii, Yoichiro; Tsuchiya, Kimiyuki; Nawa, Yukifumi

    2004-01-01

    Polymerase chain reaction (PCR) was applied to identify tissue-embedded ascarid nematode larvae. Two sequences of the internal transcribed spacer (ITS) regions of ribosomal DNA (rDNA), ITS1 and ITS2, of the ascarid parasites were amplified and compared with those of ascarid-nematodes registered in a DNA database (GenBank). The ITS sequences of the PCR products obtained from the ascarid parasite specimen in our laboratory were compatible with those of registered adult Ascaris and Toxocara parasites. PCR amplification of the ITS regions was sensitive enough to detect a single larva of Ascaris suum mixed with porcine liver tissue. Using this method, ascarid larvae embedded in the liver of a naturally infected turkey were identified as Toxocara canis. These results suggest that even a single larva embedded in tissues from patients with larva migrans could be identified by sequencing the ITS regions.

  5. Starvation-Induced Dietary Behaviour in Drosophila melanogaster Larvae and Adults.

    Science.gov (United States)

    Ahmad, Muhammad; Chaudhary, Safee Ullah; Afzal, Ahmed Jawaad; Tariq, Muhammad

    2015-09-24

    Drosophila melanogaster larvae are classified as herbivores and known to feed on non-carnivorous diet under normal conditions. However, when nutritionally challenged these larvae exhibit cannibalistic behaviour by consuming a diet composed of larger conspecifics. Herein, we report that cannibalism in Drosophila larvae is confined not only to scavenging on conspecifics that are larger in size, but also on their eggs. Moreover, such cannibalistic larvae develop as normally as those grown on standard cornmeal medium. When stressed, Drosophila melanogaster larvae can also consume a carnivorous diet derived from carcasses of organisms belonging to diverse taxonomic groups, including Musca domestica, Apis mellifera, and Lycosidae sp. While adults are ill-equipped to devour conspecific carcasses, they selectively oviposit on them and also consume damaged cadavers of conspecifics. Thus, our results suggest that nutritionally stressed Drosophila show distinct as well as unusual feeding behaviours that can be classified as detritivorous, cannibalistic and/or carnivorous.

  6. Phylogenetics links monster larva to deep-sea shrimp.

    Science.gov (United States)

    Bracken-Grissom, Heather D; Felder, Darryl L; Vollmer, Nicole L; Martin, Joel W; Crandall, Keith A

    2012-10-01

    Mid-water plankton collections commonly include bizarre and mysterious developmental stages that differ conspicuously from their adult counterparts in morphology and habitat. Unaware of the existence of planktonic larval stages, early zoologists often misidentified these unique morphologies as independent adult lineages. Many such mistakes have since been corrected by collecting larvae, raising them in the lab, and identifying the adult forms. However, challenges arise when the larva is remarkably rare in nature and relatively inaccessible due to its changing habitats over the course of ontogeny. The mid-water marine species Cerataspis monstrosa (Gray 1828) is an armored crustacean larva whose adult identity has remained a mystery for over 180 years. Our phylogenetic analyses, based in part on recent collections from the Gulf of Mexico, provide definitive evidence that the rare, yet broadly distributed larva, C. monstrosa, is an early developmental stage of the globally distributed deepwater aristeid shrimp, Plesiopenaeus armatus. Divergence estimates and phylogenetic relationships across five genes confirm the larva and adult are the same species. Our work demonstrates the diagnostic power of molecular systematics in instances where larval rearing seldom succeeds and morphology and habitat are not indicative of identity. Larval-adult linkages not only aid in our understanding of biodiversity, they provide insights into the life history, distribution, and ecology of an organism.

  7. Competência de peixes como predadores de larvas de Aedes aegypti, em condições de laboratório Efficacy of fish as predators of Aedes aegypti larvae, under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Luciano Pamplona de Góes Cavalcanti

    2007-08-01

    Full Text Available OBJETIVO: Avaliar a competência de peixes na predação de larvas de Aedes aegypti, em condições de laboratório. MÉTODOS: Foram testados machos e fêmeas de cinco espécies de peixe. Os testes de predação duravam cinco semanas para cada espécie. Cada ensaio compreendia quatro caixas testes e quatro caixas controles. Das caixas controle, duas tinham somente um peixe e as outras duas, apenas larvas. Cada caixa teste continha um peixe e larvas. Na primeira semana foram expostas 100 larvas em cada caixa, e a cada semana acrescentavam-se 100 larvas por caixa/dia, até se obter um máximo de 500 larvas/dia. Comprimento e peso dos peixes foram medidos semanalmente. RESULTADOS: Foram utilizadas 369.000 larvas no total. O Trichogaster trichopteros foi a única espécie em que ambos os sexos predaram 100% das larvas oferecidas. O Betta splendens deixou de predar apenas 15 larvas. Machos do Poecilia reticulata apresentaram baixa capacidade larvófaga quando comparados às fêmeas da mesma espécie. Em relação ao peso e tamanho o Betta splendens mostrou-se capaz de predar 523 larvas/grama/dia. CONCLUSÕES: Fêmeas e machos de Trichogaster trichopteros e de Astyanax fasciatus, e fêmeas de Betta splendens e de Poecillia sphenops foram os peixes que apresentaram maior competência para predar as larvas. Embora com competência menor, machos de Poecillia sphenops e fêmeas de Poecilia reticulata foram capazes de eliminar o número de larvas de Aedes aegypti que possam emergir durante 24 horas num criadouro, em condições naturais. Machos de Poecilia reticulata não foram predadores eficazes.OBJECTIVE: To evaluate the efficacy of fish as predators of the Aedes aegypti larvae in laboratory conditions. METHODS: The male and female of five different fish were included in the experiment. The tests to measure their consumption ability lasted five weeks for each species. Each trial involved four test tanks and four control tanks. Two control tanks

  8. Weight changes and organ pathology in rats given edible larvae of ...

    African Journals Online (AJOL)

    Processing the larvae by boiling and sun-drying reduced the toxicity on the liver and heart but not in the kidney. More research is needed on the toxicological aspects of the consumption of Cirina forda larva. Keywords: insect larvae, processing, entomophagy, histopathology, rats. African Journal of Biomedical Research Vol.

  9. DISTRIBUSI, KELIMPAHAN DAN VARIASI UKURAN LARVA IKAN DI ESTUARIA SUNGAI MUSI

    Directory of Open Access Journals (Sweden)

    Eko Prianto

    2016-03-01

    Full Text Available Penelitian tentang distribusi, kelimpahan dan ukuran larva ikan dilakukan pada bulan Maret, Mei, Juni dan Oktober 2011. Stasiun pengambilan contoh meliputi Muara Delta Upang (stasiun 1, Muara Sungai Musi (stasiun 2 dan Pulau Payung (stasiun 3. Pengambilan larva pada siang hari menggunakan Bongo net yang berukuran mata jaring 250 µm. Hasil identifikasi diperoleh 13 famili ditinjau menurut musim, pada bulan Mei dan Oktober masing-masing diperoleh 7 famili, dan pada bulan juni sebanyak 3 famili. Kelimpahan larva ikan berkisar antara 9-46 ind/m3 dengan jumlah yang tertinggi (46 ind/m3 pada bulan Mei dan terendah pada bulan Juni (9 ind/m3. Larva ikan dari famili Gobiidae memiliki sebaran yang cukup luas baik spasial maupun temporal. Variasi ukuran larva ikan menurut famili setiap bulannya memiliki variasi ukuran yang hampir sama.  Research about the distribution, abundance and size of fish larvae was conducted in March, May, June and October 2011. Sampling stations encompasses Delta Upang (station 1, Muara Sungai Musi (station 2 and Pulau Payung (station 3. Larvae taken during the daytime using a Bongo net with mesh size of 250 µm. Identification results obtained 13 families based on the season, in May and October respectively 7 families, and in June as many as 3 families. Abundance of fish larval around 9-46 ind/m3 with the highest number (46 ind/m3 in May and the lowest in June (9 ind/m3. Larvae of Gobiidae family have a large distribution on spatial and temporal. The variation in size of fish larvae by family on each month are the same.

  10. PREVALENCE OF ANISAKID NEMATODE LARVAE INFECTING SOME MARINE FISHES FROM THE LIBYAN COAST.

    Science.gov (United States)

    Kassem, Hamed H; Bowashi, Salem Mohamed

    2015-12-01

    This study examined eight hundred ninety six marine fishes belonging to nine different fish species; Synodus saurus; Merluccius merluccius; Trachurus mediterraneus; Serranus cabrilla; Mullus surmuletus; Diplodus annularis; Spicara maena; Siganus rirulatus and Liza ramada. The fishes were bought from fish markets at five different sites on Libyan coast, from January to December 2013, for study the anisakids larvae among them. The results showed that 344/896 fishes (38.4%) were infected with Anisakids larvae. S. saurus was the highly infected (80.9%), followed by T mediterraneus (77.5%) but, S. cabrilla, S. maena, M merluccius, M surmuletus, and D. annularis were least anisakid infected showed rates of 58.2%, 53.8%, 43.7%, 36.7% & 3.6%, respectively. No parasites were in S. rirulatus and L, ramada. Ten species of Anisakids larvae was detected during the present study. Two Pseudoterranova sp. Larvae, two types of Anisakis larvae, Anisakis simplex larva and Anisakis sp. Larva, two types of Contracaecum sp. Larvae and four Hysterothylacium larvae. Females showed higher prevalence than males. The number of anisakid larvae varied according to body length and weight of infected fish, without significant difference between prevalence and seasons, but, a significant difference was between prevalence and regions.

  11. Lagrangian Observations and Modeling of Marine Larvae

    Science.gov (United States)

    Paris, Claire B.; Irisson, Jean-Olivier

    2017-04-01

    Just within the past two decades, studies on the early-life history stages of marine organisms have led to new paradigms in population dynamics. Unlike passive plant seeds that are transported by the wind or by animals, marine larvae have motor and sensory capabilities. As a result, marine larvae have a tremendous capacity to actively influence their dispersal. This is continuously revealed as we develop new techniques to observe larvae in their natural environment and begin to understand their ability to detect cues throughout ontogeny, process the information, and use it to ride ocean currents and navigate their way back home, or to a place like home. We present innovative in situ and numerical modeling approaches developed to understand the underlying mechanisms of larval transport in the ocean. We describe a novel concept of a Lagrangian platform, the Drifting In Situ Chamber (DISC), designed to observe and quantify complex larval behaviors and their interactions with the pelagic environment. We give a brief history of larval ecology research with the DISC, showing that swimming is directional in most species, guided by cues as diverse as the position of the sun or the underwater soundscape, and even that (unlike humans!) larvae orient better and swim faster when moving as a group. The observed Lagrangian behavior of individual larvae are directly implemented in the Connectivity Modeling System (CMS), an open source Lagrangian tracking application. Simulations help demonstrate the impact that larval behavior has compared to passive Lagrangian trajectories. These methodologies are already the base of exciting findings and are promising tools for documenting and simulating the behavior of other small pelagic organisms, forecasting their migration in a changing ocean.

  12. Annual and spatial variability in endo- and ectoparasite infections of North Sea cod (Gadus morhua Linnaeus, 1758) larvae, post-larvae and juveniles

    DEFF Research Database (Denmark)

    Mehrdana, Foojan; Bahlool, Qusay Z. M.; Skovgaard, Alf

    2014-01-01

    A parasitological investigation was performed on a total of 5380 Atlantic cod larvae, post-larvae and small juveniles sampled from the North Sea during a period of five years. The copepod Caligus elongatus (Von Nordmann, 1832) and the nematode Hysterothylacium aduncum (Rudolphi, 1802) were found ...

  13. Three different agglomerations of blood cells in a Caliroa limacina larva

    NARCIS (Netherlands)

    Barendrecht, G.

    1949-01-01

    Some time ago in our laboratory a number of larvae of Caliroa limacina Retz., the well known slug like sawfly larva of the pear, were fixed in toto and sectioned into complete series, which were coloured with EHRLICH’S or HEIDENHAIN’S haematoxylin and counterstained with eosin. Most of these larvae

  14. Chrysomya megacephala (Fabricius) larvae: A new biodiesel resource

    International Nuclear Information System (INIS)

    Li, Zhuoxue; Yang, Depo; Huang, Miaoling; Hu, Xinjun; Shen, Jiangang; Zhao, Zhimin; Chen, Jianping

    2012-01-01

    Highlights: ►Chrysomya megacephala larvae oil as a new resource transforming to biodiesel. ► Larvae were grown up on restaurant garbage for five days then oil was extracted. ► Oil content in larvae was 24.40 wt% to 26.29 wt% comparing to soybean of 20 wt%. ► Utilization of garbage reduces pollution and makes economic recycle possible. ► The properties of ultimately FAME reach the ASTM D6751 and EN 14124 standards. -- Abstract: The current energy crisis greatly affects worldwide economic development. Therefore, identifying for new energy resources is critically important. In this study, we introduce a potential biodiesel source: Chrysomya megacephala (Fabricius) larvae (CML), which are proliferative and can be fed with a variety of low cost materials, such as manure, wheat bran, rotted meat and decayed vegetation. The potential of C. megacephala (Fabricius) larvae oil (CMLO) for biodiesel applications was explored. Oil was extracted from the CML raised by feeding on restaurant garbage for five days. The oil content obtained from the dehydrated CML ranged from 24.40% to 26.29% since restaurant garbage varies in composition day to day. The acid value of the CMLO was tested to be 1.10 mg KOH/g. Four factors were subsequently considered to optimize the transesterification of CMLO to biodiesel. The optimized conditions included a 6:1 methanol to oil molar ratio, 1.6% KOH catalyst, a reaction temperature of 55 °C and a reaction time of 30 min. Under these conditions, the maximum yield of fatty acid methyl esters (FAME) from CMLO was 87.71%. Finally, properties of the FAME were within the specifications of ASTM D6751 and EN 14214 biodiesel standards. Therefore, we concluded that C. megacephala (Fabricius) larvae represent a potential alternative feedstock for biodiesel production.

  15. Vaccination of lambs with irradiated larvae of Bunostomum trigonocephalum

    International Nuclear Information System (INIS)

    Srivastava, V.K.; Singh, K.S.; Subramanian, G.

    1987-01-01

    Vaccination with a single dose of 2,000 infective larvae of Bunostomum trigonocephalum, irradiated at 40 kR, caused 80 per cent reduction in worm establishment and such lambs withstood a challenge infection which was otherwise fatal to non-vaccinated lambs. The female worms, which developed from irradiated larvae, were irregular in shape, had cuticular thickening at the genital opening and in many male worms the copulatory bursa was rudimentary. The sex ratio was adversely affected in worms developing from irradiated larvae. The population had preponderant sterile females and a very few male worms. (author)

  16. Morphological and behavioral development of the piracanjuba larvae Desenvolvimento morfológico e comportamental de larvas de piracanjuba

    Directory of Open Access Journals (Sweden)

    Cláudia Maria Reis Raposo Maciel

    2010-05-01

    Full Text Available The objective of this work was to study the morphologic development and the swimming and feeding behaviors of piracanjuba larvae, Brycon orbignyanus Valenciennes (1849 (Characiformes, Characidae, Bryconinae, during the period from zero to 172 hours after hatching (standard length = 3.62 - 11.94 mm. The morphological analyses were accomplished by using a trinocular stereo microscope, while the behavioral analyses were performed through periodic observations. In 28 hours after hatching, the larvae (standard length = 6.25 ± 0.13 mm showed the following structural and behavioral characteristics that made them become active predators able to overcome a larval critical phase, the beginning of exogenous feeding: presence of pigmented eyes, terminal and wide mouth, developed oral dentition, developing digestive tube, yolk sac reduction, fins and swim bladder formation, horizontal swimming, cannibalism, and predation. Intense cannibalism among larvae was verified from 26 to 72 hours. At the end of the metamorphosis - 172 hours after hatching - the larvae measuring 11.94 + 0.80 mm in standard length presented a flexed notochord, caudal fin bifurcation, dorsal and anal fin formation, synchronized movements, and formation of shoals, characteristics that together allow enhanced perception and locomotio in exploration of the environment, determining the best moment for transfering to the fishponds. New studies can contribute to commercial fish farming by improving feeding management, performance, survival, and productivity of this species.Objetivou-se estudar o desenvolvimento morfológico e os comportamentos natatório e alimentar de larvas de piracanjuba, Brycon orbignyanus Valenciennes (1849 (Characiformes, Characidae, Bryconinae no período de 0 a 172 horas após a eclosão (comprimento-padrão = 3,62 - 11,94 mm. As análises morfológicas foram realizadas com auxílio de um microscópio estereoscópico trinocular e as comportamentais, por meio de

  17. Assessment of Clarias gariepinus as a biological control agent against mosquito larvae.

    Science.gov (United States)

    Chala, Buze; Erko, Berhanu; Animut, Abebe; Degarege, Abraham; Petros, Beyene

    2016-05-31

    The emergence and spread of insecticide resistant mosquitoes renewed interest in investigating the use of larvivorous fish as a biological control agent. The potential of Clarias gariepinus fish in controlling Anopheles arabiensis and culicine larvae was assessed under laboratory and semi-field conditions. Small size (15-20 cm) C. gariepinus fish consumed greater number of mosquito larvae than the large size fish (25-40 cm) in the multivariate regression model (β = 13.36, 95 % CI = 4.57, 22.15). The Anopheles larvae consumed was greater in number than the culicines larvae consumed by the fish (β = 12.10, 95 % CI = 3.31, 20.89). The number of larvae consumed was greater during the night hours than during the light hours (β = 30.06, 95 % CI = 21.27, 38.85). Amount of supplementary fish food did not cause significant differences in the number of mosquito larvae consumed by the fish among different groups. C. gariepinus was observed to feed on mosquito larvae under laboratory and semi-field conditions. C. gariepinus fed on the larvae of An. arabiensis and culicines readily. Hence, it can be used as an alternative mosquito control agent in Ethiopia where the breeding habitats are small and localized.

  18. Oesophagostomum columbianum : immunization of young lambs using gamma ray attenuated inefective larvae

    International Nuclear Information System (INIS)

    Sharma, R.L.; Dhar, D.N.

    1987-01-01

    Infective Oesophagostomum columbianum larvae were successfully attenuated by exposing them to a gamma radiation dose levels of either 40 or 50 Krad. Lambs receiving a single vaccination dose of 2000 infective larvae attenuated at 40 Krad developed partial protection, whereas those vaccinated with similar dose of infection with 50 Krad irradiated larvae failed to develop any protection. A double vaccination schedule comprising of 500 and 2000 gamma attenuated (40 Krad) infective larvae induced a significantly higher level of protection against the challenge dose. The possible use of radiation attenuated larvae as vaccine for immunoprophylaxis against ovine Oesophagostomiasis has been discussed. (author). 11 refs., 2 tables

  19. Sun-Compass Orientation in Mediterranean Fish Larvae

    OpenAIRE

    Faillettaz , Robin; Blandin , Agathe; Paris , Claire B.; Koubbi , Philippe; Irisson , Jean-Olivier

    2015-01-01

    International audience; Mortality is very high during the pelagic larval phase of fishes but the factors that determine recruitment success remain unclear and hard to predict. Because of their bipartite life history , larvae of coastal species have to head back to the shore at the end of their pelagic episode , to settle. These settlement-stage larvae are known to display strong sensory and motile abilities, but most work has been focused on tropical, insular environments and on the influence...

  20. Activity of R(+ limonene against Anisakis larvae

    Directory of Open Access Journals (Sweden)

    Filippo Giarratana

    2015-12-01

    Full Text Available The aim of this work is to evaluate the activity of R(+ limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showing a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+ limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status.

  1. Characterization of the metabolic transformation of thiamethoxam to clothianidin in Helicoverpa armigera larvae by SPE combined UPLC-MS/MS and its relationship with the toxicity of thiamethoxam to Helicoverpa armigera larvae.

    Science.gov (United States)

    Fan, Yinjun; Shi, Xueyan

    2017-09-01

    In order to characterize the metabolic transformation of thiamethoxam (TMX) to clothianidin (CLO) in Helicoverpa armigera larvae and clarify its relationship with the insecticidal toxicity of TMX, method for determination of TMX and its metabolite clothianidin (CLO) residues in H. armigera larvae by solid phase extraction (SPE) combined UPLC-MS/MS was established. Following acetonitrile extraction and purification by SPE on florisil cartridge and C 18 cartridge sequently, and cleanup by PSA adsorption, TMX and CLO residues in H. armigera larvae were successfully determined by UPLC-MS/MS. By using the established method, the concentration-time curves of TMX and its metabolite CLO in H. armigera larvae in vivo and metabolism of TMX by microsome of H. armigera larvae midguts in vitro were studied. TMX was quickly eliminated from H. armigera larvae with the elimination half-life as 4.2h. Meanwhile, only a small amount of CLO was formed from TMX metabolism, with the maximum CLO level in H. armigera larvae only accounts for the metabolic transformation of 7.99% of TMX, at 10h after intravenous TMX administration. Our results suggested that the low insecticidal efficacy of TMX against H. armigera larvae was related with the rapidly elimination of TMX from H. armigera larvae, meanwhile, CLO as TMX metabolite at a very low level in vivo didn't contribute to TMX toxicity to H. armigera larvae. In H. armigera larvae, TMX didn't act as proinsecticide for CLO in insecticidal efficacy of TMX. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Production of live prey for marine fish larvae

    OpenAIRE

    Kraul, S

    1989-01-01

    Tropical marine fish larvae vary in their requirements for live planktonic food. Selection of live prey species for culture depends on larval size and larval tolerance of water quality. This report describes some of the cultured prey species, and their uses and limits as effective food for fish larvae. Methods are presented for the culture of phytoplankton, rotifers, copepods, and other live feeds.

  3. Larvacidal Effect of Imperata Cylindrical Root Decoction against Culex sp. Larvae

    Directory of Open Access Journals (Sweden)

    Afini Tiara Resi

    2014-08-01

    Full Text Available Background: Filariasis is one of the neglected tropical diseases. About 337 of 401 districts in Indonesia are endemic areas for filariasis, especially in Sumatera, Kalimantan, and Papua. Culex sp. is one of the lymphatic filariasis vectors which can be controlled by insecticide, including larvacide. This study was conducted to determine the larvacidal effect of Imperata cylindrical root decoction against Culex sp. larvae. Methods: This study was conducted at the Laboratory of Parasitology, Faculty of Medicine, Universitas Padjadjaran during the period of September to November 2012. The study object was Culex sp. larvae III/IV instars. The design of this study was experimental laboratory using true experimental approach. The larvae were divided into three groups: negative control (distilled water, reference (Abate®, and decoction. The number of larvae in each group was 25 larvae, and the effects were evaluated by the total number of dead larvae in 48 hours under observation. The data were then analyzed by Mann-Whitney test and Probit test. Results: The result of the Mann-Whitney test to compare Imperata cylindrica root decoction treatment to distilled water as control was significant (p<0.05. However, Abate® gave a better result. The Probit test resultwas LC50: 63% and LC90: 489%. Conclusions: Imperata cylindrical root decoction has a larvacidal effect against Culex sp. larvae.

  4. Preliminary study of killing the larva of plodia interpunella by irradiation

    International Nuclear Information System (INIS)

    Wang Jide; Ma Xiaoping

    1994-01-01

    The results of killing the larva of plodia interpunella in the fruit by 60 Co γ-irradiation are described. The lowest effective dose for killing larva by irradiation is ca. 2000 Gy; the effective dose for immediately killing larva is 3000 Gy. The method is simple and easy and also suitable for the study of commercial irradiation of dry-fruit

  5. Helminths Parasite Larvae collected from Arabian Gulf Fish. 4. Description of four Larvae including two Metacercarae, one Didymozoid and one Acanthocephalan from Emirati Coasts

    International Nuclear Information System (INIS)

    Kardousha, M.M.

    2005-01-01

    Four helminth larvae from different fish hosts caught from Emirate coasts are described. Two are metacercariae related to genus Southampton's, type (I) and (II). Type (I) was found encysted in body cavities of the Indian halibut Psettodes erumei and the areolate grouper Epinephelus areolatusu and type (II) in the golden stripped goatfish Mulloides flavolineatus. The third larva is related to Acanthocephala and identified as Serrasentis sagittifer. It was collected from the body cavity of the spotted lizard fish Saurida undosquamius. The fourth larva belongs to the didymozoid trematodes, and was found infecting the kidneys of different hosts, such as Saurida undosquamis, the Jack pomfret Parastromateus niger and mackerel tuna Euthynnus affins. The larva related to Stephanostomum type (I) and type (II) and the dydimozoid type are described for the first time in the Arabian Gulf. (author)

  6. Effect of electronic beam irradiation on last instar larvae of lasioderma serricorne fabricius

    International Nuclear Information System (INIS)

    Chen Yuntang; Guo Dongquan; Lu Xiaohua; Zhang Jianwei; Yang Baoan; Du Yueguang; Liu Jiangyu; Tian Zhanjun; Zhang Xiaoyan

    2010-01-01

    The electronic beam irradiation effects on the last instar larvae of cigarette beetle (Lasioderma serricorne Fabricius) in tobacco were studied, and the mortality in 42 days, lethal time, pupation rate, emergence rate and reproductive capacity after irradiation were measured. The results showed that the mortality increased with the increase of irradiation dosage, but the larvae did not dead immediately. The last instar larvae irradiated by the dosages higher than 480 Gy could prevent the development of larvae to adults. No new generation was found after 300 Gy treatment of the last instar larvae. So 300 Gy irradiation could be considered as a suitable dose to prevent the reproduction of cigarette beetle of the last instar larvae in the tobacco. (authors)

  7. Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Stacey M Williams

    2010-10-01

    Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.Este estudio describe patrones de abundancia temporal y espacial de larvas de

  8. Developmental Toxicity of Dextromethorphan in Zebrafish Embryos/Larvae

    Science.gov (United States)

    Xu, Zheng; Williams, Frederick E.; Liu, Ming-Cheh

    2012-01-01

    Dextromethorphan is widely used in over-the-counter cough and cold medications. Its efficacy and safety for infants and young children remains to be clarified. The present study was designed to use the zebrafish as a model to investigate the potential toxicity of dextromethorphan during the embryonic and larval development. Three sets of zebrafish embryos/larvae were exposed to dextromethorphan at 24 hours post fertilization (hpf), 48 hpf, and 72 hpf, respectively, during the embryonic/larval development. Compared with the 48 and 72 hpf exposure sets, the embryos/larvae in the 24 hpf exposure set showed much higher mortality rates which increased in a dose-dependent manner. Bradycardia and reduced blood flow were observed for the embryos/larvae treated with increasing concentrations of dextromethorphan. Morphological effects of dextromethorphan exposure, including yolk sac and cardiac edema, craniofacial malformation, lordosis, non-inflated swim bladder, and missing gill, were also more frequent and severe among zebrafish embryos/larvae exposed to dextromethorphan at 24 hpf. Whether the more frequent and severe developmental toxicity of dextromethorphan observed among the embryos/larvae in the 24 hpf exposure set, as compared with the 48 and 72 hpf exposure sets, is due to the developmental expression of the Phase I and Phase II enzymes involved in the metabolism of dextromethorphan remains to be clarified. A reverse transcription-polymerase chain reaction (RT-PCR) analysis, nevertheless, revealed developmental stage-dependent expression of mRNAs encoding SULT3 ST1 and SULT3 ST3, two enzymes previously shown to be capable of sulfating dextrorphan, an active metabolite of dextromethorphan. PMID:20737414

  9. Distribution and elimination of Norfloxacin in Fenneropenaeus chinensis larvae

    Science.gov (United States)

    Sun, Ming; Li, Jian; Zhao, Fazhen; Li, Jitao; Chang, Zhiqiang

    2013-09-01

    This study examined the distribution and elimination of Norfloxacin (NFLX) in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10 mg L-1 NFLX for 2 or 5 d. Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography (HPLC). Results showed that NFLX residue accumulated in F. chinensis eggs after the parental exposure, with the highest residue detected in ovary. To examine the fate of NFLX residue in larvae, we further determined the concentration of NFLX residue in F. chinensis eggs and larvae at 4 different developmental stages after 24-h exposure. From the newly metamorphosed larvae (0 h post-metamorphosis, h.p.m), samples were taken at different time intervals to 72 h.p.m. HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10 mg L-1 NFLX were the highest at 1.5 h, i.e., 0.332 and 0.454 μg g-1, respectively. At the two NFLX exposure levels, the elimination time of half NFLX (half life) in nauplius was 45.36 and 49.85 h, respectively, followed by that in zoea (31.68 and 33.13 h), mysis larvae (42.24 and 47.28 h) and postlarvae (24.48 and 30.96 h). Both NFLX exposure levels had a germicidal effect. The distribution and elimination of NFLX residue in F. chinensis tissue, eggs and larvae correlated well with the drug exposure level. The disappearance of NFLX residue coincided with the larval growth, and the half-life of NFLX decreased with the larval development.

  10. Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Stacey M Williams

    2010-10-01

    Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.

  11. Cutaneous larva migrans: a bad souvenir from the vacation.

    Science.gov (United States)

    Criado, Paulo Ricardo; Belda, Walter; Vasconcellos, Cidia; Silva, Cristiana Silveira

    2012-06-15

    Cutaneous larva migrans (CLM) is a common endemic disease in tropical and subtropical countries. This condition is caused by skin-penetrating larvae of nematodes, mainly of the hookworm Ancylostoma braziliense and other nematodes of the family Ancylostomidae. We report three cases of CLM acquired during vacations in different regions of Brazil.

  12. Ecological Factors Determining Abundance of Parasitic Mites on Aedes spp. Larvae

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    Nurhadi Eko Firmansyah

    2017-12-01

    Full Text Available Ability to infestation and abundance of parasitic mites in Aedes spp. larvae cannot be separated from the influence of various factors. Ecological factors have been suggested to play a role determine the presence of parasitic mites that under certain conditions become a key factor in determining the abundance of parasitic mites on Aedes spp. larvae. The aim of this study to determine the ecological factors affect the abundance of parasitic mites on Aedes spp. larvae in Bogor Regency. Capturing of Aedes spp. larvae was performed directly on the habitats found in indoor and outdoor. Capturing mites in the body of Aedes spp. larvae was performed using insect forceps. Ecological factors measured were dissolved oxygen (DO, pH, temperature, and total dissolved solid (TDS. The influence of ecological factors was analyzed using regression and correlation analysis. The result of mite identification has been obtained three species of mites that are Halacarus sp., Histiostoma sp., and Hydrozetes sp. The result indicated that total dissolved solid (TDS and temperature was the factors that determined the abundance of mites. The factors of pH, and dissolved oxygen (DO did not determine the abundance of parasitic mites of Aedes spp. larvae. The research result can be further developed as a new alternative to Dengue Hemorraghic Fever control and provide information on parasitic mites that infest Aedes spp. larvae. In addition, this results become an early step in controlling of Aedes spp. strategy platform by the parasitic mites.

  13. Description of the third instar larva of Megadytes latus (Fabricius (Coleoptera, Dytiscidae, with an identification key for described larvae of the genus Descrição da larva de terceiro ínstar de Megadytes latus (Fabricius (Coleoptera, Dytiscidae

    Directory of Open Access Journals (Sweden)

    Nelson Ferreira-Jr

    2006-09-01

    Full Text Available The last instar larva of M. latus (Fabricius, 1801 is described and figured, based on reared specimens from Serra dos Órgãos, Teresópolis, state of Rio de Janeiro, Brazil. Some notes on the biotope are provided.A larva de terceiro ínstar de M. latus (Fabricius, 1801 é descrita e ilustrada, baseado em espécimes criados da Serra dos Órgãos, Teresópolis, Rio de Janeiro, Brasil. Algumas notas acerca do biótopo onde as larvas foram coletadas são incluídas.

  14. Infective larvae of Rhabdiasidae (Nematoda): comparative morphology of seven European species.

    Science.gov (United States)

    Kuzmin, Yuriy; Junker, Kerstin; Bain, Odile

    2014-03-01

    The morphology of infective third-stage larvae of Rhabdias bufonis, R. rubrovenosa, R. sphaerocephala, R. fuscovenosa, R. elaphe, Entomelas entomelas and E. dujardini is described. The sheath structure in the studied larvae appeared to be similar to that described in other species of the family Rhabdiasidae, its chequered aspect being caused by a combination of outer longitudinal striations and inner longitudinal as well as transverse ridges. The larvae were similar in general morphology but differed in the presence/absence of anterior apical protuberances (pseudolabia), the shape and ornamentation of the tail tip, and the structure of lateral alae in the caudal region of the body. No relationship between the morphological characters of the larvae of the studied species and their taxonomic position or specificity of adult parasites to a particular host group was observed. Regardless, the larvae of each species can be identified by a combination of morphological peculiarities in the anterior and caudal regions of the body.

  15. Distribution and abundance of skipjack (Katsuwonus pelamis larvae in eastern Brazilian waters

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    Yasunobu Matsuura

    1982-01-01

    Full Text Available Based on data from two ichthyoplankton surveys carried out off the eastern Brazilian coast in June and November-December 1978, the larval distribution of skipjack is discussed. Skipjack larvae were more abundant in the November-December cruise (southern hemisphere spring. They occurred mainly at stations near the margin of the continental shelf or over seamounts. Out of 240 specimens of scombrid larvae collected in this area, skipjack larvae comprised only 10.4% (25 specimens, whereas the most abundant larvae were Thunnus spp. with 68.8% (165 specimens.

  16. Experimental infection in Notodiaptomus sp. (Crustacea: Calanoida with larvae of Camallanus sp. (Nematoda: Camallanidae Infecção experimental em Notodiaptomus sp. (Crustacea: Calanoida com larvas de Camallanus sp. (Nematoda: Camallanidae

    Directory of Open Access Journals (Sweden)

    M.L. Martins

    2007-04-01

    Full Text Available This trial registered the experimental infection viability with nematode larvae Camallanus sp. in Notodiaptomus sp., a crustacean, which can be an intermediate host. Adult females of nematode were dissected from the intestines of Xiphophorus maculatus (Osteichthyes: Poeciliidae, at a fish farm in the State of São Paulo. Females were slightly compressed for larvae release, collected with Pasteur pipette and separated on Petri dishes with 9ml filtered water at 28.1ºC, from zooplankton culture. Treatments consisted of Petri dishes with 60 and 105 copepods, in which 120, 150 and 210 larvae of nematode were added in four replications. Twenty-four and 36h after exposition to the larvae, the copepods were fixed in 70% alcohol to record the amount of fixed larvae. Twenty four hours after exposition, 60 copepods group with 120 larvae showed significantly higher prevalence (46.5% when compared to 105 copepods and 120 larvae (33.2%. Thus, these answers suggested that 120 larvae were enough for a successful infectivity. Experimental infection was available and so, it was used as a pattern to life cycle studies of camallanid nematodes and hosts susceptibility tests.A viabilidade da infecção experimental com larvas do nematóide Camallanus sp. em Notodiaptomus sp., crustáceo com potencial para hospedeiro intermediário foi avaliada. Fêmeas adultas do nematóide foram extraídas de Xiphophorus maculatus (Osteichthyes: Poeciliidae, provenientes de piscicultura de peixes ornamentais no estado de São Paulo. As fêmeas foram ligeiramente pressionadas para liberar as larvas, coletadas com pipeta Pasteur e separadas em placas de Petri contendo 9ml de água filtrada a 28,1ºC do próprio cultivo de zooplâncton. Os tratamentos consistiram de placas contendo 60 e 105 copépodes onde se adicionou 120, 150 e 210 larvas de nematóides em quatro repetições. Nos tempos de 24 e 36h após a exposição às larvas, os copépodes foram fixados em álcool 70% para

  17. Microplastic ingestion in fish larvae in the western English Channel.

    Science.gov (United States)

    Steer, Madeleine; Cole, Matthew; Thompson, Richard C; Lindeque, Penelope K

    2017-07-01

    Microplastics have been documented in marine environments worldwide, where they pose a potential risk to biota. Environmental interactions between microplastics and lower trophic organisms are poorly understood. Coastal shelf seas are rich in productivity but also experience high levels of microplastic pollution. In these habitats, fish have an important ecological and economic role. In their early life stages, planktonic fish larvae are vulnerable to pollution, environmental stress and predation. Here we assess the occurrence of microplastic ingestion in wild fish larvae. Fish larvae and water samples were taken across three sites (10, 19 and 35 km from shore) in the western English Channel from April to June 2016. We identified 2.9% of fish larvae (n = 347) had ingested microplastics, of which 66% were blue fibres; ingested microfibers closely resembled those identified within water samples. With distance from the coast, larval fish density increased significantly (P < 0.05), while waterborne microplastic concentrations (P < 0.01) and incidence of ingestion decreased. This study provides baseline ecological data illustrating the correlation between waterborne microplastics and the incidence of ingestion in fish larvae. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. High magnetic field induced otolith fusion in the zebrafish larvae.

    Science.gov (United States)

    Pais-Roldán, Patricia; Singh, Ajeet Pratap; Schulz, Hildegard; Yu, Xin

    2016-04-11

    Magnetoreception in animals illustrates the interaction of biological systems with the geomagnetic field (geoMF). However, there are few studies that identified the impact of high magnetic field (MF) exposure from Magnetic Resonance Imaging (MRI) scanners (>100,000 times of geoMF) on specific biological targets. Here, we investigated the effects of a 14 Tesla MRI scanner on zebrafish larvae. All zebrafish larvae aligned parallel to the B0 field, i.e. the static MF, in the MRI scanner. The two otoliths (ear stones) in the otic vesicles of zebrafish larvae older than 24 hours post fertilization (hpf) fused together after the high MF exposure as short as 2 hours, yielding a single-otolith phenotype with aberrant swimming behavior. The otolith fusion was blocked in zebrafish larvae under anesthesia or embedded in agarose. Hair cells may play an important role on the MF-induced otolith fusion. This work provided direct evidence to show that high MF interacts with the otic vesicle of zebrafish larvae and causes otolith fusion in an "all-or-none" manner. The MF-induced otolith fusion may facilitate the searching for MF sensors using genetically amenable vertebrate animal models, such as zebrafish.

  19. Cutaneous larva migrans – a threat to divers in the tropics

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    Olszański Romuald

    2016-09-01

    Full Text Available The article presents a dermatosis that occurs in tropical and subtropical countries. Though the definitive hosts of the cutaneous larva migrans parasite are animals, humans can become accidental hosts and they are infected when their skin comes into contact with damp soil, most frequently sand. The disease is only present in the epidermis where an itch is brought about by the mining activity of the larva. Sunbathers and divers who put on their gear on a beach, on account of the epidermis maceration caused by a prolonged exposure to water, are particularly susceptible to the penetrative activities of the larva. In Poland the cutaneous larva migrans is in most cases mistaken for nettle rash or eczema.

  20. Morphogenesis of Strongyloides stercoralis infective larvae requires the DAF-16 ortholog FKTF-1.

    Directory of Open Access Journals (Sweden)

    Michelle L Castelletto

    2009-04-01

    Full Text Available Based on metabolic and morphological similarities between infective third-stage larvae of parasitic nematodes and dauer larvae of Caenorhabditis elegans, it is hypothesized that similar genetic mechanisms control the development of these forms. In the parasite Strongyloides stercoralis, FKTF-1 is an ortholog of DAF-16, a forkhead transcription factor that regulates dauer larval development in C. elegans. Using transgenesis, we investigated the role of FKTF-1 in S. stercoralis' infective larval development. In first-stage larvae, GFP-tagged recombinant FKTF-1b localizes to the pharynx and hypodermis, tissues remodeled in infective larvae. Activating and inactivating mutations at predicted AKT phosphorylation sites on FKTF-1b give constitutive cytoplasmic and nuclear localization of the protein, respectively, indicating that its post-translational regulation is similar to other FOXO-class transcription factors. Mutant constructs designed to interfere with endogenous FKTF-1b function altered the intestinal and pharyngeal development of the larvae and resulted in some transgenic larvae failing to arrest in the infective stage. Our findings indicate that FKTF-1b is required for proper morphogenesis of S. stercoralis infective larvae and support the overall hypothesis of similar regulation of dauer development in C. elegans and the formation of infective larvae in parasitic nematodes.

  1. Irradiation effect of electronic beam on older larvae of Lasioderma serricorne (Fabricius)

    International Nuclear Information System (INIS)

    Chen Yuntang; Guo Dongquan; Zhang Jianwei; Yang Baoan

    2010-01-01

    Cigarette beetle [ Lasioderma serricorne (Fabricius) ] is an important pest of stored tobacco distributing over the world, and it is also one of the most serious pests in the tobacco warehouse. The larvae is the most serious detriment in the four states of cigarette beetle. The objective of this study was to control the damage on tobacco from cigarette beetle. The irradiation effects of electronic beam on the older larvae of cigarette beetle in tobacco were studied. The results showed that the older larvae irradiated by the doses higher than 480 Gy could prevent the development to adults; and no new generation was found after 300 Gy irradiation for older larvae. Thus 300Gy irradiation could prevent the reproduction of cigarette beetle for the older larvae in the tobacco. (authors)

  2. Activity of Selected Formulated Biorational and Synthetic Insecticides Against Larvae of Helicoverpa armigera (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Vivan, L M; Torres, J B; Fernandes, P L S

    2017-02-01

    This work studied 17 insecticides belonging to nucleopolyhedrovirus (NPV), Bacillus thuringiensis (Bt kurstaki and Bt aizawai), benzoylureas (insect growth regulators [IGRs]), carbamates, organophosphates, spinosyns, and diamides against larvae of Helicoverpa armigera (Hübner), invasive species in the South American continent. Larvae of different instars were fed for 7 d with untreated or insecticide-treated diets. Mortality was recorded daily for 7 d, and surviving larvae were individually weighed on the seventh day. The NPV and Bt insecticides caused 100% mortality of first-instar larvae and first-instar and second-instar larvae, respectively. However, both NPV and Bt-based products caused low mortality of third-instar larvae and did not kill older larvae. The IGR lufenuron was highly effective against all three ages of larvae tested, whereas teflubenzuron and triflumuron produced maximum 60% mortality of second-instar larvae and lower than 50% to older larvae. Thiodicarb, chlorantraniliprole, indoxacarb, chlorpyrifos, and chlorfenapyr, irrespective of tested age, caused 100% mortality of larvae, with the last two insecticides reaching 100% mortality within 2 d of feeding on the treated diet. Flubendiamide caused lower mortality but significantly affected the weight of surviving larvae, whereas neither spinosad nor methomyl produced significant mortality or affected the weight of larvae. Based on the results, the age of H. armigera larvae plays an important role in the recommendation of NPV and Bt insecticides. Furthermore, there are potential options between biological and synthetic insecticides tested against H. armigera, and recording larval size during monitoring, in addition to the infestation level, should be considered when recommending biological-based insecticides to control this pest. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Effects of benzylisoquinoline alkaloids on the larvae of polyphagous Lepidoptera.

    Science.gov (United States)

    Miller, James S; Feeny, Paul

    1983-06-01

    Six benzylisoquinoline alkaloids were fed to the larvae of three polyphagous Lepidoptera species: Hyphantria cunea, Spodoptera eridania, and Lymantria dispar. Exposure of last instar larvae to alkaloid-containing diets over a 24-h period resulted in reduced feeding rates and reduced growth efficiencies. Lymantria dispar larvae reared from eggs on alkaloid diets took longer to reach the fifth instar, attained lower larval weights, and showed reduced survivorship. The benzylisoquinolines tested were not equally effective as toxins or feeding inhibitors. Some produced dramatic effects while others produced no effects. The relative responses of the three caterpillar species to the six alkaloids were similar. Those benzylisoquinolines with a methylene-dioxyphenyl (1,3-benzodioxole) group were consistently the most toxic or repellent while laudanosine, a relatively simple benzylisoquinoline, was generally innocuous. Available host records indicate that benzylisoquinoline-containing plants are avoided by the larvae of these moth species.

  4. Habitat stability and occurrences of malaria vector larvae in western Kenya highlands

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    Atieli Harrysone

    2009-10-01

    Full Text Available Abstract Background Although the occurrence of malaria vector larvae in the valleys of western Kenya highlands is well documented, knowledge of larval habitats in the uphill sites is lacking. Given that most inhabitants of the highlands actually dwell in the uphill regions, it is important to develop understanding of mosquito breeding habitat stability in these sites in order to determine their potential for larval control. Methods A total of 128 potential larval habitats were identified in hilltops and along the seasonal streams in the Sigalagala area of Kakamega district, western Kenya. Water availability in the habitats was followed up daily from August 3, 2006 to February 23, 2007. A habitat is defined as stable when it remains aquatic continuously for at least 12 d. Mosquito larvae were observed weekly. Frequencies of aquatic, stable and larvae positive habitats were compared between the hilltop and seasonal stream area using χ2-test. Factors affecting the presence/absence of Anopheles gambiae larvae in the highlands were determined using multiple logistic regression analysis. Results Topography significantly affected habitat availability and stability. The occurrence of aquatic habitats in the hilltop was more sporadic than in the stream area. The percentage of habitat occurrences that were classified as stable during the rainy season is 48.76% and 80.79% respectively for the hilltop and stream area. Corresponding frequencies of larvae positive habitats were 0% in the hilltop and 5.91% in the stream area. After the rainy season, only 23.42% of habitat occurrences were stable and 0.01% larvae positive habitats were found in the hilltops, whereas 89.75% of occurrences remained stable in the stream area resulting in a frequency of 12.21% larvae positive habitats. The logistic regression analysis confirmed the association between habitat stability and larval occurrence and indicated that habitat surface area was negatively affecting the

  5. Inhibitory effect of indole analogs against Paenibacillus larvae, the causal agent of American foulbrood disease.

    Science.gov (United States)

    Alvarado, Israel; Margotta, Joseph W; Aoki, Mai M; Flores, Fernando; Agudelo, Fresia; Michel, Guillermo; Elekonich, Michelle M; Abel-Santos, Ernesto

    2017-09-01

    Paenibacillus larvae, a Gram-positive bacterium, causes American foulbrood (AFB) in honey bee larvae (Apis mellifera Linnaeus [Hymenoptera: Apidae]). P. larvae spores exit dormancy in the gut of bee larvae, the germinated cells proliferate, and ultimately bacteremia kills the host. Hence, spore germination is a required step for establishing AFB disease. We previously found that P. larvae spores germinate in response to l-tyrosine plus uric acid in vitro. Additionally, we determined that indole and phenol blocked spore germination. In this work, we evaluated the antagonistic effect of 35 indole and phenol analogs and identified strong inhibitors of P. larvae spore germination in vitro. We further tested the most promising candidate, 5-chloroindole, and found that it significantly reduced bacterial proliferation. Finally, feeding artificial worker jelly containing anti-germination compounds to AFB-exposed larvae significantly decreased AFB infection in laboratory-reared honey bee larvae. Together, these results suggest that inhibitors of P. larvae spore germination could provide another method to control AFB. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  6. Simulating the impact of the entrainment of winter flounder larvae

    International Nuclear Information System (INIS)

    Hess, K.W.; Sissenwine, M.P.; Saila, S.B.

    1975-01-01

    The transport of winter flounder larvae around the Millstone Point, Conn. Area by the action of tidal currents and diffusion was simulated by computer to predict the numbers which could be entrained during the operation of a local nuclear power station. A tidal hydrodynamic model with variable depth was employed to simulate currents and water levels. These techniques provided input to a transport model which simulated the concentration of larvae. A larval source in a tributary river was simulated for twenty tidal cycles, with and without entrainment. The results indicated that the reduction in winter flounder larvae near Millstone Point at the end of the pelagic stage (period during which larvae are likely to be entrained) was less than 1 percent when it was assumed that larvae have little chance of returning once lost from Millstone bight. In order to assess the effect of a 1 percent reduction in recruitment of winter flounder larvae to the benthic phase of their life cycle, the local population was simulated by a model in which year-classes and the total egg production were represented by compartments. Each year-class grew, produced eggs, suffered natural and fishing mortality according to information derived from the literature. The effect of power plant entrainment was incorporated by reducing the number of recruits to year-class I that would normally result from a specific level of egg production. For a 1 percent reduction in recruitment due to power plant entrainment, a potential 6 percent decrease in total population size following 35 years of operation was indicated. (U.S.)

  7. Studies on immunization with irradiated larvae against dictyocaulus filaria in guinea-pigs

    International Nuclear Information System (INIS)

    Akyol, F.; Cerci, H.; Duzgun, A.

    1986-01-01

    In this study, 32 guinea-pigs were immunized orally with two doses of infective D. filaria attenuated by exposure to 40 krad (group I) and 50 krad (group II) of Cs-137 source at 15 days interval. The first dose was administrated as 1000 larvae and the second was 2000 larvae. After 15 days of the second infection they were challenged with 5000 non-irradiated infective larvae. Eight guinea-pigs were used as control (group III). The control group received the challenge only. The controls developed signs of lungworm disease and 3 animals died after 10 days of challenge. The vaccinated animals showed no clinical signs. All of the surviving animals were killed 12 days after challenge and their lungs were carefully examined for detailed parasitological and pathomorphological examinations. At autopsy, an average of 91 worms was recovered from the lungs of control groups. Four worms recovered from animals given larvae irradiated at 40 krad and the pathological changes were the lightest in this group. It was established that gamma rays at 50 krad attenuated infective larvae of D. filaria to such a degree that their administration did not cause any serious pathomorphological effect in the lungs of the animals. A higher degree of protection against challenge with infective D. filaria larvae was confered on the guinea-pigs by double dose of irradiated larvae. (auhtor)

  8. Development Of Enzyme Digestive Activity Of Blue Crab Portunus Pelagicus Larvae

    OpenAIRE

    Nikhlani, Andi; Sukarti, Komsanah

    2017-01-01

    Seed production continuity of Portunus pelagicus larvae had been conducted but the results were still un-consistent Digestive activity was known to be associated with the type of feed consumed by larvae. Amylase, lipase, and trypsin enzymes were used as a biological indicators to measure the digestion of feed. The aim of this study was to describe the activity of digestive enzymes in blue swimming crab larvae. Digestive enzyme activity data obtained was presented in graphical form and anal...

  9. Chemical Composition and Food Potential of Pachymerus nucleorum Larvae Parasitizing Acrocomia aculeata Kernels.

    Directory of Open Access Journals (Sweden)

    Ariana Vieira Alves

    Full Text Available Insect consumption as food is culturally practiced in various regions of the world. In Brazil, there are more than 130 species of edible insects registered, from nine orders, among which stands out the Coleoptera. The larva of the beetle Pachymerus nucleorum Fabricius, 1792, grows into the bocaiuva fruit (Acrocomia aculeata (Jacq. Lodd. Ex Mart., 1845, which has proven nutritional quality. The aim of this work was to evaluate the nutritional potential of P. nucleorum larvae compared to bocaiuva kernels for human consumption. Proteins were the second largest portion of the larvae nutritional composition (33.13%, with percentage higher than the bocaiuva kernels (14.21%. The larval lipid content (37.87% was also high, very close to the kernels (44.96%. The fraction corresponding to fatty acids in the oil extracted from the larvae was 40.17% for the saturated and 46.52% for the unsaturated. The antioxidant activity value was 24.3 uM trolox/g of oil extracted from larvae. The larvae tryptic activity was 0.032±0.006 nmol BAPNA/min. Both the larvae and the bocaiuva kernel presented absence of anti-nutritional factors. These results favor the use of P. nucleorum larvae as food, which are a great protein and lipid sources with considerable concentrations of unsaturated fatty acids compared to the bocaiuva kernel.

  10. Cultivation of sponge larvae: settlement, survival, and growth of juveniles

    NARCIS (Netherlands)

    Caralt, de S.; Otjens, H.; Uriz, M.J.; Wijffels, R.H.

    2007-01-01

    The aim of this study was to culture sponge juveniles from larvae. Starting from larvae we expected to enhance the survival and growth, and to decrease the variation in these parameters during the sponge cultures. First, settlement success, morphological changes during metamorphosis, and survival of

  11. Effects of coded-wire-tagging on stream-dwelling Sea Lamprey larvae

    Science.gov (United States)

    Johnson, Nicholas; Swink, William D.; Dawson, Heather A.; Jones, Michael L.

    2016-01-01

    The effects of coded wire tagging Sea Lamprey Petromyzon marinus larvae from a known-aged stream-dwelling population were assessed. Tagged larvae were significantly shorter on average than untagged larvae from 3 to 18 months after tagging. However, 30 months after tagging, the length distribution of tagged and untagged larvae did not differ and tagged Sea Lampreys were in better condition (i.e., higher condition factor) and more likely to have undergone metamorphosis than the untagged population. The reason why tagged larvae were more likely to metamorphose is not clear, but the increased likelihood of metamorphosis could have been a compensatory response to the period of slower growth after tagging. Slower growth after tagging was consistent across larval size-classes, so handling and displacement from quality habitat during the early part of the growing season was likely the cause rather than the tag burden. The tag effects observed in this study, if caused by displacement and handling, may be minimized in future studies if tagging is conducted during autumn after growth has concluded for the year.

  12. Pengaruh ukuran tubuh ikan Poecilia reticulata pada daya pemangsaannya terhadap larva Culex quinquefasciatus

    Directory of Open Access Journals (Sweden)

    Noer Moehammadi

    1999-06-01

    Full Text Available The research aimed to know the influence of poecilia reticulata body size, in the feeding capacity on Culex quinquifasciatus larvae. The research was experimental method with Complete Random Design., each treatment with 5 replications. The taken body size of Poecilia reticulata were; 1,50 cm; 2.50 cm; and 3.50 cm. the size of fish €™s body was measured from the tip of snout up to the end of fin (cm. The feeding capacity was determined by subtracting the first amount of larvae which was given the rest of larvae after 24 hours. The result showed that the difference of size of Poecilia reticulate body was significantly different in the feeding capacity on Culex quinquifasciatus larvae. The fish whose body size was 1.50 cm had the lowest feeding capacity by eating 77.2 larvae for average, and the highest one was the fist which body size was 2.50 cm by eating 113.6 larvae for average, subsequently the feeding capacity decrease to the fish which body size was 3.50 cm because of eating 100,6 larvae for 24 hours.

  13. Direct Effects of Microalgae and Protists on Herring (Clupea harengus Yolk Sac Larvae.

    Directory of Open Access Journals (Sweden)

    Björn Illing

    Full Text Available This study investigated effects of microalgae (Rhodomonas baltica and heterotrophic protists (Oxyrrhis marina on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus larvae from hatch, through the end of the endogenous (yolk sac period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW. In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin and nutritional condition (RNA-DNA ratio markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish.

  14. Direct Effects of Microalgae and Protists on Herring (Clupea harengus) Yolk Sac Larvae.

    Science.gov (United States)

    Illing, Björn; Moyano, Marta; Niemax, Jan; Peck, Myron A

    2015-01-01

    This study investigated effects of microalgae (Rhodomonas baltica) and heterotrophic protists (Oxyrrhis marina) on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus) larvae from hatch, through the end of the endogenous (yolk sac) period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier) and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW). In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin) and nutritional condition (RNA-DNA ratio) markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish.

  15. Tadpoles of three common anuran species from Thailand do not prey on mosquito larvae.

    Science.gov (United States)

    Weterings, Robbie

    2015-12-01

    Tadpoles are often considered to be predators of mosquito larvae and are therefore beneficial for the control of certain disease vectors. Nevertheless, only a few species have actually been recorded to prey on mosquito larvae. The mosquito larvae predation rates of tadpoles of three common Thai anuran species (Bufo melanostictus, Kaloula pulchra and Hylarana raniceps) were experimentally tested. Tadpoles in varying developmental stages were used to assess a size/age effect on the predation rate. In addition, different instars of Culex quinquefasciatus were used in order to assess a prey size effect on the predation rates. All three species failed to show any evidence of mosquito larvae predation. Neither small nor large tadpoles fed on mosquito larvae. Prey size also did not affect predation. Although tadpoles do not feed on mosquito larvae, there may be other direct or indirect inter-specific interactions that adversely impact the development of larvae in shared habitats with tadpoles. © 2015 The Society for Vector Ecology.

  16. PENGARUH PAKAN ALAMI Chaetoceros spp. TERHADAP PERKEMBANGAN DAN SINTASAN LARVA UDANG WINDU, Penaeus monodon

    Directory of Open Access Journals (Sweden)

    Samuel Lante

    2015-09-01

    Full Text Available Pakan alami berupa mikroalga merupakan salah satu faktor pendukung dalam keberhasilan usaha pembenihan udang windu, Penaeus monodon. Penelitian ini bertujuan untuk mengetahui jenis pakan alami, Chaetoceros spp., yang dapat meningkatkan pertumbuhan dan sintasan larva udang windu. Penelitian ini menggunakan 15 buah bak fiber berukuran 60 cm x 40 cm x 50 cm dengan volume 120 liter yang disi air sebanyak 100 liter. Kepadatan naupli adalah 90 ekor/liter atau 9.000 ekor/bak dan lima jenis pakan alami Chaetoceros spp. yang diuji yaitu: Chaetoceros simplex, Chaetoceros ceratosporum, Chaetoceros calcitrans, Chaetoceros amami, dan Chaetoceros gracilis. Hasil penelitian menunjukkan bahwa aplikasi kelima jenis pakan alami memberikan laju perkembangan larva yang relatif sama sampai stadia PL-1. Aplikasi Chaetoceros gracilis memberikan sintasan larva udang windu tertinggi yaitu 41,48% dan dengan Chaetoceros simplex memberikan sintasan larva terendah (28,02%. Hasil penelitian ini mengindikasikan bahwa aplikasi Chaetoceros spp. yang berbeda pada pemeliharaan larva berpengaruh terhadap sintasan larva udang windu, namun tidak berpengaruh terhadap laju metamorfosis larva. Aplikasi Chaetoceros gracilis sebagai pakan alami adalah terbaik untuk sintasan larva udang windu.

  17. Rapid bioassay to screen potential biopesticides in Tenebrio molitor larvae

    Science.gov (United States)

    A simplified assay was devised to evaluate the response of Tenebrio molitor larvae to potential insect control products. The assay incorporates punched disks of flattened whole-grain bread placed in 96-well plates, with treatments applied topically, and neonate larvae added to each well. To evalua...

  18. c-orfi and Tnpnin crnssiceps Larvae I Department of Pharmaceutical ...

    African Journals Online (AJOL)

    satisfactorily. The putative first intermediate host is a ground-dwelling coprophagous arthropod that ingests oncospheres and accommodates the development of larvae. It is presumed that vertebrates become hosts for the larvae after ingestion of infected arthropods. This is followed by penetration of the small intestine by a.

  19. Production of the catechol type siderophore bacillibactin by the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Hertlein, Gillian; Müller, Sebastian; Garcia-Gonzalez, Eva; Poppinga, Lena; Süssmuth, Roderich D; Genersch, Elke

    2014-01-01

    The Gram-positive bacterium Paenibacillus larvae is the etiological agent of American Foulbrood. This bacterial infection of honey bee brood is a notifiable epizootic posing a serious threat to global honey bee health because not only individual larvae but also entire colonies succumb to the disease. In the recent past considerable progress has been made in elucidating molecular aspects of host pathogen interactions during pathogenesis of P. larvae infections. Especially the sequencing and annotation of the complete genome of P. larvae was a major step forward and revealed the existence of several giant gene clusters coding for non-ribosomal peptide synthetases which might act as putative virulence factors. We here present the detailed analysis of one of these clusters which we demonstrated to be responsible for the biosynthesis of bacillibactin, a P. larvae siderophore. We first established culture conditions allowing the growth of P. larvae under iron-limited conditions and triggering siderophore production by P. larvae. Using a gene disruption strategy we linked siderophore production to the expression of an uninterrupted bacillibactin gene cluster. In silico analysis predicted the structure of a trimeric trithreonyl lactone (DHB-Gly-Thr)3 similar to the structure of bacillibactin produced by several Bacillus species. Mass spectrometric analysis unambiguously confirmed that the siderophore produced by P. larvae is identical to bacillibactin. Exposure bioassays demonstrated that P. larvae bacillibactin is not required for full virulence of P. larvae in laboratory exposure bioassays. This observation is consistent with results obtained for bacillibactin in other pathogenic bacteria.

  20. Enantiomerization and enantioselective bioaccumulation of metalaxyl in Tenebrio molitor larvae.

    Science.gov (United States)

    Gao, Yongxin; Wang, Huili; Qin, Fang; Xu, Peng; Lv, Xiaotian; Li, Jianzhong; Guo, Baoyuan

    2014-02-01

    The enantiomerization and enantioselective bioaccumulation of metalaxyl by a single dose of exposure to Tenebrio molitor larvae under laboratory condition were studied by high-performance liquid chromatography tandem mass spectroscopy (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carbamate)] column. Exposure of enantiopure R-metalaxyl and S-metalaxyl in Tenebrio molitor larvae exhibited significant enantiomerization, with formation of the R enantiomers from the S enantiomers, and vice versa, which might be attributed to the chiral pesticide catalyzed by a certain enzyme in Tenebrio molitor larvae. Enantiomerization was not observed in wheat bran during the period of 21 d. In addition, bioaccumulation of rac-metalaxyl in Tenebrio molitor larvae was enantioselective with a preferential accumulation of S-metalaxyl. These results showed that enantioselectivity was caused not only by actual degradation and metabolism but also by enantiomerization, which was an important process in the environmental fate and behavior of metalaxyl enantiomers. Copyright © 2013 Wiley Periodicals, Inc.

  1. Cutaneous larva migrans in northern climates. A souvenir of your dream vacation.

    Science.gov (United States)

    Edelglass, J W; Douglass, M C; Stiefler, R; Tessler, M

    1982-09-01

    Three young women recently returned to the metropolitan Detroit area with cutaneous larva migrans. All three had vacationed at a popular club resort on the Caribbean island of Martinique. Cutaneous larva migrans is frequently seen in the southern United States, Central and South America, and other subtropical areas but rarely in northern climates. Several organisms can cause cutaneous larva migrans, or creeping eruption. The larvae of the nematode Ancylostoma braziliense are most often the causative organisms. Travel habits of Americans make it necessary for practitioners in northern climates to be familiar with diseases contracted primarily in warmer locations. The life cycle of causative organisms and current therapy are reviewed.

  2. The use of morphological and histological features as nutritional condition indices of Pagrus pagrus larvae

    Directory of Open Access Journals (Sweden)

    Marina Vera Diaz

    Full Text Available Morphometrical and histological techniques were employed to characterize Pagrus pagrus larvae nutritional condition. Larvae were reared in laboratory under controlled conditions with the main objective of testing whether these methodologies allowed finding differences between larvae from different feeding treatments. Once yolk was consumed (three days after hatching larvae were assigned to a feeding treatment: starved during the whole experiment; delayed feeding, starved during three days; fed during the entire experiment. Algae (Nannochloropsis oculata and rotifers (Brachionus plicatilis were provided to larvae for feed treatments. Larvae were fixed daily; for morphometrical purposes in 5% formaldehyde solution, and in Bouin for histological sections. Results herein obtained showed that both methodologies are sensitive enough to distinguish larvae characterized by different nutritional condition states obtained from the feeding treatments. Consequently, these methodologies could be employed in wild red porgy larvae in order to asses their nutritional condition. These techniques could also be employed to check larval quality obtained with aquaculture purposes to estimate the effects of changes in rearing protocols or kind of food supply and thus, to guaranty a higher survival of early developmental stages of reared larvae.

  3. Estuarine retention of larvae of the crab Rhithropanopeus harrisii

    Science.gov (United States)

    Cronin, Thomas W.

    1982-08-01

    Larvae of estuarine organisms continually face possible export from the parent estuary. Retention of larvae of the estuarine crab Rhithropanopeus harrisii was investigated in the upper Newport River estuary, North Carolina. All of the developmental stages occurred in the same area of the estuary with similar horizontal distributions, and the concentrations of intermediate and late stages were not greatly reduced from those of the first larval stage. This was strong evidence for the continuous retention of larvae in the upper estuary. To determine mechanisms by which retention might be effected, field studies of the vertical distributions and migrations of these larvae were made. The four zoeal stages had similar but complex vertical migration patterns, which varied from study to study. These migrations centered on the depth of no net flow, reducing longitudinal transport during development. Cross-spectral analysis of the larval migrations and the environmental cycles of light, salinity and current speed revealed that each of these external cycles affected larval depth. Megalopae of R. harrisii also migrated vertically, but they were present in much lower concentrations than the zoeal stages, an indication of a change to benthic existence in this final larval form.

  4. Nematode cysts and larvae found in Achatina fulica Bowdich, 1822.

    Science.gov (United States)

    Franco-Acuña, D O; Pinheiro, J; Torres, E J L; Lanfredi, R M; Brandolini, S V P B

    2009-02-01

    This study describes the morphology of the nematode cysts and larvae found in Achatina fulica (giant African snail) in Brazil. Sixty snails were collected in Mesquita, Rio de Janeiro State. Fourteen of the snails were naturally infected. The cysts were spherical, pink colored and measured 0.97 to 1.57 mm in diameter. In the majority of cases they had a single larvae involved in amorphous material. A total of 222 encysted larvae were recovered. Of these, 30 were utilized in the morphological study. The length of the larvae varied from 2.57 to 5.8 mm and they were classified as small--up to 3.5 mm; medium--from 3.53 to 4.5 mm; and large--greater than 4.52 mm. The average length of the larvae in the three groups was 2.85, 3.87 and 5.23 mm, respectively. The larval cuticle was white, shiny and transversally striated until the posterior end of the body. At the anterior end there is a mouth with three lips, with amphids and papillae, followed by a muscular esophagus with average length of 0.61 mm, terminating in an esophageal bulb and having a nerve ring in the middle third of the esophagus, and an intestine with an opening near the posterior end. The tail begins from this opening and has two types of ends: short and abrupt or long and gradually tapering. The difference in the tail end can suggest sexual dimorphism, although no primordial reproductive structures were observed. These characteristics were not sufficient to identify the larvae, so there is a need for further study.

  5. Seasonal occurrence and abundance of caridean shrimp larvae at Helgoland, German Bight

    Science.gov (United States)

    Wehrtmann, Ingo S.

    1989-03-01

    Plankton samples were collected from January 1985 to January 1986 three times per week at Helgoland to study seasonal occurrence and abundance of caridean shrimp larvae. A total of eleven species were obtained. Ninety-one % of all larvae collected during the sample period belonged to Crangon crangon L. and Crangon allmanni Kinahan, 6% to Philocheras trispinosus Hailstone and 3% to the remaining eight species. Collections were generally dominated by C. crangon larvae. However, C. allmanni larvae were most abundant in June coinciding with hatching activities of the population near Helgoland. C. allmanni was observed to have the highest density of all species with approximately 8 larvae per m3. Larvae of Eualus occultus (Lebour), Eualus pusiolus (Kroyer), Hippolyte varians Leach and Athanas nitescens Leach were most likely released by populations inhabiting the rocky intertidal zone around Helgoland. The presence of Processa modica Williamson & Rochanaburanon and Processa nouveli holthuisi Al-Adhub & Williamson in the German Bight was verified by observations of a series of different developmental stages. Larvae of the rare species Caridion steveni Lebour were also recorded. The observed shrimp species were placed into three different groups with respect to their seasonal occurrence. Possible advantages of the timing of larval dispersal relative to predation and food availability are given. The results on seasonal occurrence and relative abundance are discussed in relation to environmental factors (temperature, salinity) as well as to the geographical distribution of the species.

  6. Larvicidal activity of Cybistax antisyphilitica against Aedes aegypti larvae.

    Science.gov (United States)

    Rodrigues, A M S; de Paula, J E; Roblot, F; Fournet, A; Espíndola, L S

    2005-12-01

    The larvicidal activity against Aedes aegypti larvae of a stem wood hexane extract of Cybistax antisyphilitica was evaluated. Bioassay-guided fractionation of the crude extract, monitored by larvicidal assay, led to the isolation of a natural quinone identified as 2-hydroxy-3-(3-methyl-2-butenyl)-1.4-naphthoquinone (lapachol). This compound was quite potent against A. aegypti larvae (LC50 26.3 microg/ml).

  7. Occurrence of digenean larvae in freshwater snails in the Ruvu ...

    African Journals Online (AJOL)

    Occurrence of digenean larvae in freshwater snails in the Ruvu basin, Tanzania. G Nkwengulila, ESP Kigadye. Abstract. A survey was carried out on digenean larvae infecting freshwater snails in five habitats in Dar es Salaam, Ruvu and Morogoro. 9424 snails belonging to 12 species from five families were examined for ...

  8. Scanning electron microscope observations of brine shrimp larvae from space shuttle experiments

    Science.gov (United States)

    DeBell, L.; Paulsen, A.; Spooner, B.

    1992-01-01

    Brine shrimp are encysted as gastrula stage embryos, and may remain dehydrated and encysted for years without compromising their viability. This aspect of brine shrimp biology is desirable for studying development of animals during space shuttle flight, as cysts placed aboard a spacecraft may be rehydrated at the convenience of an astronaut, guaranteeing that subsequent brine shrimp development occurs only on orbit and not on the pad during launch delays. Brine shrimp cysts placed in 5 ml syringes were rehydrated with salt water and hatched during a 9 day space shuttle mission. Subsequent larvae developed to the 8th larval stage in the sealed syringes. We studied the morphogenesis of the brine shrimp larvae and found the larvae from the space shuttle experiments similar in rate of growth and extent of development, to larvae grown in sealed syringes on the ground. Extensive differentiation and development of embryos and larvae can occur in a microgravity environment.

  9. Predator response to releases of American shad larvae in the Susquehanna River basin

    Science.gov (United States)

    Johnson, James H.; Ringler, N.H.

    1998-01-01

    Predation on American shad (Alosa sapidissima) larvae within the first two hours of release was examined from 1989 to 1992 on 31 occasions at stocking sites in the Susquehanna River basin. Twenty-two fish species consumed shad larvae; the dominant predators were spotfin shiner (Cyprinella spiloptera), mimic shiner (Notropis volucellus) and juvenile smallmouth bass (Micropterus dolomieu). The number of shad larvae found in predator stomachs ranged from 0 to 900. Mortality of shad larvae at the stocking site was usually less than 2%. The greatest mortality (9.6%) occurred at the highest stocking level (1.5 million larvae). Highly variable predation rates and release levels of shad insufficient to achieve predator satiation hindered the ability to determine a specific type of functional response of predators. Predator numbers increased with stocking density, indicating short-term aggregation at the release site. Because of practical problems associated with releasing the large numbers of larvae that would be required to satiate predators, routine stocking at these levels is probably unreasonable. Releases of 400,000 to 700,000 larvae may reduce predation by offsetting depensatory mechanisms that operate on small releases and the effects of increased predation due to predator aggregation on large releases. Night stocking may reduce predation on larval shad at the release site.

  10. Clash of kingdoms or why Drosophila larvae positively respond to fungal competitors

    Directory of Open Access Journals (Sweden)

    Rohlfs Marko

    2005-01-01

    Full Text Available Abstract Background Competition with filamentous fungi has been demonstrated to be an important cause of mortality for the vast group of insects that depend on ephemeral resources (e.g. fruit, dung, carrion. Recent data suggest that the well-known aggregation of Drosophila larvae across decaying fruit yields a competitive advantage over mould, by which the larvae achieve a higher survival probability in larger groups compared with smaller ones. Feeding and locomotor behaviour of larger larval groups is assumed to cause disruption of fungal hyphae, leading to suppression of fungal growth, which in turn improves the chances of larval survival to the adult stage. Given the relationship between larval density, mould suppression and larval survival, the present study has tested whether fungal-infected food patches elicit communal foraging behaviour on mould-infected sites by which larvae might hamper mould growth more efficiently. Results Based on laboratory experiments in which Drosophila larvae were offered the choice between fungal-infected and uninfected food patches, larvae significantly aggregated on patches containing young fungal colonies. Grouping behaviour was also visible when larvae were offered only fungal-infected or only uninfected patches; however, larval aggregation was less strong under these conditions than in a heterogeneous environment (infected and uninfected patches. Conclusion Because filamentous fungi can be deadly competitors for insect larvae on ephemeral resources, social attraction of Drosophila larvae to fungal-infected sites leading to suppression of mould growth may reflect an adaptive behavioural response that increases insect larval fitness and can thus be discussed as an anti-competitor behaviour. These observations support the hypothesis that adverse environmental conditions operate in favour of social behaviour. In a search for the underlying mechanisms of communal behaviour in Drosophila, this study highlights

  11. Attempts at immunization against Malayan filariasis using X-irradiated infective larvae

    International Nuclear Information System (INIS)

    Ramachandran, C.P.

    1975-01-01

    Recent studies on immunity to helminthic infections have shown that some degree of protective immunity may be stimulated by inoculations of attenuated living worms or their metabolites. Although much on these lines has been done with several helminths, little if any has been done with filarial infections in general. Experiments were designed to observe the effects of attempted immunization in the rhesus monkey as well as the domestic cat by the use of attenuated infective larvae of Brugia malayi. The sub-periodic strain of Brugia malayi, the major filarial parasite of man in Malaysia, maintained in the laboratory on experimentally infected cats and rhesus monkeys were used for the preparation of X-irradiated vaccines as well as for challenge inoculations. Third-stage infective larvae of Brugia malayi were obtained from experimentally fed Aedes togoi mosquitoes. Infective larvae were irradiated by X-rays, using a Dermopan X-ray unit at exposures between 10 - 40 kR. Rhesus monkeys and cats were inoculated twice with 100 - 400 attenuated larvae per inoculation at 2 week intervals and challenged about a month later by inoculation of 100 normal larvae. Control animals for each vaccination dose as well as for challenge doses were maintained. In rhesus monkeys persistent immunity to challenge infections (expressed as failure to cause microfilaraemia) were obtained in animals vaccinated with 200 infective larvae attenuated by X-irradiation at 20000 R. Encouraged with the results obtained on rhesus monkeys, similar experiments on an enlarged scale using varying strengths of the vaccines were carried out on the domestic cat, which is a more receptive animal host for Brugia malayi. However, all cats vaccinated when challenged came down with patent infection indicating lack of any definite immunity. In all these experiments, results of vaccine control animals showed that inoculation of irradiated larvae was not followed by the infection of microfilaria in the blood, indicating

  12. [Infestation of the human digestive system with beetle larvae (Coleoptera: Cantharidae): a case report].

    Science.gov (United States)

    Yılmaz, Hasan; Taş Cengiz, Zeynep; Dülger, Ahmet Cumhur; Ekici, Pınar

    2014-12-01

    This study was conducted to report the digestive system infestation caused by the larvae of Coleoptera in a female pediatric patient. She was admitted to our hospital with the complaints of emergence of insect larvae from her vomit and feces, abdominal pain, inguinal pain, lack of appetite, hair loss, excessive cleaning behavior, extreme irritability, and distractibility. The larvae observed typically had the morphology of the larvae of insects related to the Cantharidae family in the Coleoptera order. For treatment, a single dose of albendazole (400 mg) was used. Consequently, in the present case, it was seen that the larvae of Coleoptera incidentally taken orally could continue to live for a period in the digestive tract of people, without losing vitality, and the larvae caused a variety of symptoms due to both their toxic agents and the possible irritation they caused.

  13. Infestation of a bird and two cats by larvae of Plodia interpunctella (Lepidoptera: Pyralidae).

    Science.gov (United States)

    Pinckney, R D; Kanton, K; Foster, C N; Steinberg, H; Pellitteri, P

    2001-09-01

    The larvae of Plodia interpunctella (Hübner), commonly known as the Indian meal moth, often cause enormous losses in stored food supplies. We present three clinical case reports of accidental infestation by P. interpunctella larvae in two domestic cats and one parakeet. A larva gained entry into the avian host and subsequently migrated to the brain. It was alive, covered with "silk-like" fibers and confirmed to be a fourth instar. Plodia interpunctella larvae were excised with forceps from the subcutaneous tissues of the ear and neck of two cats in a different household. Previous reports of infestation by P. interpunctella larvae in vertebrates are unknown.

  14. Feeding ecology of lake whitefish larvae in eastern Lake Ontario

    Science.gov (United States)

    Johnson, James H.; McKenna, James E.; Chalupnicki, Marc A.; Wallbridge, Tim; Chiavelli, Rich

    2009-01-01

    We examined the feeding ecology of larval lake whitefish (Coregonus clupeaformis) in Chaumont Bay, Lake Ontario, during April and May 2004-2006. Larvae were collected with towed ichthyoplankton nets offshore and with larval seines along the shoreline. Larval feeding periodicity was examined from collections made at 4-h intervals over one 24-h period in 2005. Inter-annual variation in diet composition (% dry weight) was low, as was spatial variation among collection sites within the bay. Copepods (81.4%), primarily cyclopoids (59.1%), were the primary prey of larvae over the 3-year period. Cladocerans (8.1%; mainly daphnids, 6.7%) and chironomids (7.3%) were the other major prey consumed. Larvae did not exhibit a preference for any specific prey taxa. Food consumption of lake whitefish larvae was significantly lower at night (i.e., 2400 and 0400 h). Substantial variation in diet composition occurred over the 24-h diel study. For the 24-h period, copepods were the major prey consumed (50.4%) and their contribution in the diet ranged from 29.3% (0400 h) to 85.9% (1200 h). Chironomids made up 33.4% of the diel diet, ranging from 8.0% (0800 h) to 69.9% (0400 h). Diel variation in the diet composition of lake whitefish larvae may require samples taken at several intervals over a 24-h period to gain adequate representation of their feeding ecology.

  15. A Single Swede Midge (Diptera: Cecidomyiidae) Larva Can Render Cauliflower Unmarketable.

    Science.gov (United States)

    Stratton, Chase A; Hodgdon, Elisabeth A; Zuckerman, Samuel G; Shelton, Anthony M; Chen, Yolanda H

    2018-05-01

    Swede midge, Contarinia nasturtii Kieffer (Diptera: Cecidomyiidae), is an invasive pest causing significant damage on Brassica crops in the Northeastern United States and Eastern Canada. Heading brassicas, like cauliflower, appear to be particularly susceptible. Swede midge is difficult to control because larvae feed concealed inside meristematic tissues of the plant. In order to develop damage and marketability thresholds necessary for integrated pest management, it is important to determine how many larvae render plants unmarketable and whether the timing of infestation affects the severity of damage. We manipulated larval density (0, 1, 3, 5, 10, or 20) per plant and the timing of infestation (30, 55, and 80 d after seeding) on cauliflower in the lab and field to answer the following questions: 1) What is the swede midge damage threshold? 2) How many swede midge larvae can render cauliflower crowns unmarketable? and 3) Does the age of cauliflower at infestation influence the severity of damage and marketability? We found that even a single larva can cause mild twisting and scarring in the crown rendering cauliflower unmarketable 52% of the time, with more larvae causing more severe damage and additional losses, regardless of cauliflower age at infestation.

  16. Infectivity of Trichinella spiralis larvae in pork buried in the ground

    Directory of Open Access Journals (Sweden)

    Jovic S.

    2001-06-01

    Full Text Available Time of survival and infectivity of Trichinella spiralis larvae in pig muscle tissue, buried at various depths in the ground were assessed. In the pork pieces the number of infective larvae was 250 ML/g. Meat originated from pig halves was divided in 39 equal pieces, 0.7 kg each, disposed in three groups of 1 3, and buried in depths of 30, 50, and 100 centimeters respectively. The pork was dug up at 13 intervals, approximately every week, until 91st day of the experiment. After each time interval, infectivity of larvae was assessed by bioassay on rats. The artificially infected rats were sacrificed on 42nd day after the infection and meat was examined by the following methods - artificial digestion and trichinoscopy. It was found that the larvae during all 90 days preserved infectivity in each depth.

  17. CalCOFI Larvae Counts Positive Tows

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for eggs captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  18. Preliminary screening of plant essential oils against larvae of Culex ...

    African Journals Online (AJOL)

    Preliminary screenings of 22 plant essential oils were tested for mortality of the mosquito larvae Culex quinquefasciatus under laboratory conditions. Percent (%) mortality of the mosquito larvae were obtained for each essential oil. At different exposure periods, viz. 1, 3, 6, 12 and 24 h among the 22 plant oils tested, eight ...

  19. Acute intestinal anisakiasis in Spain: a fourth-stage Anisakis simplex larva

    Directory of Open Access Journals (Sweden)

    Mª José Rosales

    1999-11-01

    Full Text Available A case of acute intestinal anisakiasis has been reported; a nematode larva being found in the submucosa of the ileum of a woman in Jaén (Spain. The source of infection was the ingestion of raw Engraulis encrasicholus. On the basis of its morphology, the worm has been identified as a fourth-stage larva of Anisakis simplex. In Spain, this is the ninth report of human anisakiasis and also probably the first case of anisakiasis caused by a fourth-stage larva of A. simplex.

  20. Maintained larval growth in mussel larvae exposed to acidified under-saturated seawater

    Science.gov (United States)

    Ventura, Alexander; Schulz, Sabrina; Dupont, Sam

    2016-03-01

    Ocean acidification (OA) is known to affect bivalve early life-stages. We tested responses of blue mussel larvae to a wide range of pH in order to identify their tolerance threshold. Our results confirmed that decreasing seawater pH and decreasing saturation state increases larval mortality rate and the percentage of abnormally developing larvae. Virtually no larvae reared at average pHT 7.16 were able to feed or reach the D-shell stage and their development appeared to be arrested at the trochophore stage. However larvae were capable of reaching the D-shell stage under milder acidification (pHT ≈ 7.35, 7.6, 7.85) including in under-saturated seawater with Ωa as low as 0.54 ± 0.01 (mean ± s. e. m.), with a tipping point for normal development identified at pHT 7.765. Additionally growth rate of normally developing larvae was not affected by lower pHT despite potential increased energy costs associated with compensatory calcification in response to increased shell dissolution. Overall, our results on OA impacts on mussel larvae suggest an average pHT of 7.16 is beyond their physiological tolerance threshold and indicate a shift in energy allocation towards growth in some individuals revealing potential OA resilience.

  1. Acute ecotoxicology of natural oil and gas condensate to coral reef larvae.

    Science.gov (United States)

    Negri, Andrew P; Brinkman, Diane L; Flores, Florita; Botté, Emmanuelle S; Jones, Ross J; Webster, Nicole S

    2016-02-19

    Risks posed by oil spills to coral reefs are difficult to evaluate, partially due to the absence of studies that adequately assess toxicity to relevant coral reef species. Here we experimentally tested the acute toxicity of condensate, representing a fraction of light crude oil, to coral (Acropora tenuis) and sponge (Rhopaloeides odorabile) larvae. The metamorphosis of coral larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations of water accommodated fractions (WAF) as low as 103 μg l(-1), similar to concentrations detected in seawater following large spills. The sensitivity of coral larvae increased by 40% when co-exposed to UV light that they might encounter in shallow reefal systems. Condensate WAF was more toxic to coral larvae than predicted by summing the toxicity of its main components (benzene, toluene, p-xylene and napthalene). In contrast, the sensitivity of sponge larvae to condensate WAF (>10,000 μg l(-1) TPAH) was far less than coral in the presence and absence of UV, but similar to that of other marine invertebrates. While these results highlight the relative sensitivity of coral larvae to oil, further research is needed to better understand and predict the impacts and risks posed by hydrocarbons to tropical reef systems.

  2. Effects of gamma radiation on the melanization process in larvae of stored product moths

    International Nuclear Information System (INIS)

    Lupa, D.

    1998-01-01

    Non-irradiated larvae of the Indian meal moth (Plodia interpunctella Hbn.), the Mediterranean flour moth (Ephestia (Anagasta) kuehniella Zell.), and the almond moth (Cadra cautella Wlk.) showed strong melanization after killing by freezing. However, there were some insects which showed lack of melanization or melanized only partly, sometimes like those that have been irradiated. A part of the larval body was dark black while the rest body was of natural color or only slightly gray. Also, black and gray patches were observed in the larvae. After the irradiation treatment, the number of non-melanized larvae and larvae exhibiting a slight melanization usually increased. The degree of melanization in the treated larvae was significantly different from the untreated insects. Generally, it decreased with increasing dose and time elapsed after the treatment. The melanization test for detecting irradiated moth larvae may produce inconsistent results because (a) irradiation does not completely prevent melanization in mature moth larvae, and (b) the untreated larvae, killed by freezing and examined at room temperature, often show incomplete melanization. An ideal method for detection of irradiated insects should be: (1 ) specific for irradiation and not influenced by other processes, (2) accurate and reproducible, (3) have a detection limit below the minimum dose likely to be applied to agricultural commodity as a quarantine treatment, (4) applicable to a range of pests, (5) quick and easy to perform, and (6) capable of providing an estimate of irradiation dose. The melanization test to detect irradiated larvae of the stored product moths fulfills only some of these requirements. Therefore, additional studies were performed to improve this test before it is recommended for quarantine inspection. Because visual assessment of the effects of irradiation on melanization of the moth larvae is very subjective and difficult to perform, a trial to determine the activity of

  3. Modulation of nutrient composition of black soldier fly (Hermetia illucens) larvae by feeding seaweed-enriched media.

    Science.gov (United States)

    Liland, Nina S; Biancarosa, Irene; Araujo, Pedro; Biemans, Daan; Bruckner, Christian G; Waagbø, Rune; Torstensen, Bente E; Lock, Erik-Jan

    2017-01-01

    Black soldier fly (Hermetia illucens) larvae are a promising source of protein and lipid for animal feeds. The nutritional composition of the BSF larvae depend partly on the composition of the feeding medium. The BSF lipid profile in part mimics the feeding media lipid profile, and micronutrients, like minerals and vitamins, can readily accumulate in black soldier fly larvae. However, investigative studies on bioconversion and accumulation of nutrients from media to black soldier fly larvae are scarce. Here we show that inclusion of the brown algae Ascophyllum nodosum in the substrate for black soldier fly larvae can introduce valuable nutrients, commonly associated with the marine environment, into the larvae. The omega-3 fatty acid eicosapentaenoic acid (20:5n-3), iodine and vitamin E concentrations increased in the larvae when more seaweed was included in the diet. When the feeding media consisted of more than 50% seaweed, the larvae experienced poorer growth, lower nutrient retention and lower lipid levels, compared to a pure plant based feeding medium. Our results confirm the plasticity of the nutritional make-up of black soldier fly larvae, allowing it to accumulate both lipid- and water-soluble compounds. A broader understanding of the effect of the composition of the feeding media on the larvae composition can help to tailor black soldier fly larvae into a nutrient profile more suited for specific feed or food purposes.

  4. Eficiência de extratos vegetais no controle de Diabrotica speciosa (Germar, 1824 (Coleoptera: Chrysomelidae, em laboratório

    Directory of Open Access Journals (Sweden)

    Junir Antonio Lutinski

    2010-04-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2010v23n1p83 Vulgarmente conhecida como “vaquinha”, Diabrotica speciosa (Germar, 1824 ocorre na maioria dos estados brasileiros, destacando-se como uma das mais importantes pragas do feijoeiro e do milho. Visando avaliar a atividade inseticida de extratos brutos aquosos de nove espécies vegetais sobre os adultos deste inseto, realizou-se este trabalho. O experimento, conduzido em laboratório, foi realizado sob delineamento completamente casualizado, com dez tratamentos e quatro repetições. Para tal, utilizou-se um frasco, contendo em seu interior cinco espécimes adultos e uma folha de feijoeiro (Phaseolus vulgaris Linnaeus previamente imersa no extrato, tampado com um recorte de pano poroso e fixado por uma borracha. A variável avaliada foi número de espécimes de D. speciosa vivos. Os tratamentos consistiram em extratos de salvia (Salvia officinalis Linnaeus, cravo (Eugenia caryophyllata Thunb, noz-moscada (Myristica fragans Houtt, cinamomo (Melia azedarach Linnaeus, timbó (Ateleia glazioveana Baill, eucalipto (Eucalyptus citriodora Hook, canela (Cinnamomum zeylanicum Blume, figueira (Ficus microcarpa Linnaeus f., alecrim (Rosmarinus officinalis Linnaeus e a testemunha (apenas água destilada. As avaliações de sobrevivência foram realizadas a cada 24 horas, durante 10 dias. Sobre o número de espécimes vivos efetuou-se a análise de variância em bifatorial (10 extratos x 11 horários após a aplicação. As médias foram agrupadas pelo teste de Duncan ao nível de 5% de probabilidade de erro. Os extratos mais eficientes foram o timbó, noz-moscada e cinamomo, com porcentagens de eficiência variando entre 80,4% e 100%.

  5. The hatching larva of the priapulid worm Halicryptus spinulosus

    OpenAIRE

    Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

    2009-01-01

    Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid developmen...

  6. DNA metabarcoding of fish larvae for detection of non-native fishes

    Science.gov (United States)

    Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection because...

  7. Feeding by larvae of intertidal invertebrates: assessing their position in pelagic food webs.

    Science.gov (United States)

    Vargas, Cristian A; Manríquez, Patricio H; Navarrete, Sergio A

    2006-02-01

    One of the leading determinants of the structure and dynamics of marine populations is the rate of arrival of new individuals to local sites. While physical transport processes play major roles in delivering larvae to the shore, these processes become most important after larvae have survived the perils of life in the plankton, where they usually suffer great mortality. The lack of information regarding larval feeding makes it difficult to assess the effects of food supply on larval survival, or the role larvae may play in nearshore food webs. Here, we examine the spectrum of food sizes and food types consumed by the larvae of two intertidal barnacle species and of the predatory gastropod Concholepas concholepas. We conducted replicated experiments in which larvae were exposed to the food size spectrum (phytoplankton, microprotozoan and autotrophic picoplankton) found in nearshore waters in central Chile. Results show that barnacle nauplii and gastropod veligers are omnivorous grazers, incorporating significant fractions of heterotrophs in their diets. In accordance with their feeding mechanisms and body size, barnacle nauplii were able to feed on autotrophic picoplankton (concholepas larvae also consumed picoplankton cells, while competent larvae of this species ingested mostly the largest phytoplankton cells and heterotrophic protozoans. Results suggest that persistent changes in the structure of pelagic food webs can have important effects on the species-specific food availability for invertebrate larvae, which can result in large-scale differences in recruitment rates of a given species, and in the relative recruitment success of the different species that make up benthic communities.

  8. Influence of UV-irradiation on the nauplius larvae of the barnacle Chthamalus sp

    International Nuclear Information System (INIS)

    Hori, Masayuki; Nagayama, Shougo; Kawabe, Atsushi; Yamashita, Keiji.

    1990-01-01

    The purpose of this study is to investigate the influence of UV-irradiation on the nauplius larvae of the barnacle and to use this as the basis for researching the possibility of UV-irradiation as a new method for anti-macrofouling control. The nauplius larvae in the petri dishes were exposed to UV-irradiation (λ max = 253.7 nm), then the larval states and behaviour were observed. UV-intensisties were 3.0 mW·cm -2 -7.0 mW·cm -2 and the exposure time was 15 sec -10 min. The water in the petri dishes was changed intermittently but the larvae were not fed. The results were as follows: 1) UV-irradiation may have a delayed lethal effect and metamorphosis-inhibitory effect on the nauplius larvae. 2) The lethal effect of the sum of the dosages of UV on the larvae may nearly equate each other despite differences in each UV-intensity. 3) Within ca. 72 hr, 100 % of UV-irradiated larvae were dead with the dosage of at least 672 mW·sec·cm -2 and were incapable of swimming with the dosage of at least 168 mW·sec·cm -2 . 4) UV-irradiated larvae could not exuviate with the dosage of at least 246 mW·sec·cm -2 and could only exuviate with the dosage of 45 mW·sec·cm -2 . 5) After UV-irradiation even the 'actively swimming' larvae may have suffered some sort of physiological damage. (author)

  9. Effect of bodily fluids from honey bee (Apis mellifera) larvae on growth and genome-wide transcriptional response of the causal agent of American Foulbrood disease (Paenibacillus larvae).

    Science.gov (United States)

    De Smet, Lina; De Koker, Dieter; Hawley, Alyse K; Foster, Leonard J; De Vos, Paul; de Graaf, Dirk C

    2014-01-01

    Paenibacillus larvae, the causal agent of American Foulbrood disease (AFB), affects honey bee health worldwide. The present study investigates the effect of bodily fluids from honey bee larvae on growth velocity and transcription for this Gram-positive, endospore-forming bacterium. It was observed that larval fluids accelerate the growth and lead to higher bacterial densities during stationary phase. The genome-wide transcriptional response of in vitro cultures of P. larvae to larval fluids was studied by microarray technology. Early responses of P. larvae to larval fluids are characterized by a general down-regulation of oligopeptide and sugar transporter genes, as well as by amino acid and carbohydrate metabolic genes, among others. Late responses are dominated by general down-regulation of sporulation genes and up-regulation of phage-related genes. A theoretical mechanism of carbon catabolite repression is discussed.

  10. An unprecedented role reversal: ground beetle larvae (Coleoptera: Carabidae lure amphibians and prey upon them.

    Directory of Open Access Journals (Sweden)

    Gil Wizen

    Full Text Available Amphibians often feed on beetle larvae, including those of ground beetles (Carabidae. Preliminary reports have detailed an unusual trophic interaction in which, in contrast, larvae of the ground beetle Epomis prey upon juvenile and adult amphibians. While it is known that these larvae feed exclusively on amphibians, how the predator-prey encounter occurs to the advantage of the beetle larvae had been unknown to date. Using laboratory observations and controlled experiments, we recorded the feeding behavior of Epomis larvae, as well as the behavior of their amphibian prey. Here we reveal that larvae of two species of Epomis (E. circumscriptus and E. dejeani lure their potential predator, taking advantage of the amphibian's predation behavior. The Epomis larva combines a sit-and-wait strategy with unique movements of its antennae and mandibles to draw the attention of the amphibian to the presence of a potential prey. The intensity of this enticement increases with decreasing distance between the larva and the amphibian. When the amphibian attacks, the larva almost always manages to avoid the predator's protracted tongue, exploiting the opportunity to attach itself to the amphibian's body and initiate feeding. Our findings suggest that the trophic interaction between Epomis larvae and amphibians is one of the only natural cases of obligatory predator-prey role reversal. Moreover, this interaction involves a small insect larva that successfully lures and preys on a larger vertebrate. Such role reversal is exceptional in the animal world, extending our perspective of co-evolution in the arms race between predator and prey, and suggesting that counterattack defense behavior has evolved into predator-prey role reversal.

  11. Impact of ultraviolet-B radiation on planktonic fish larvae: Alteration of the osmoregulatory function

    Energy Technology Data Exchange (ETDEWEB)

    Sucre, Elliott, E-mail: elliott.sucre@univ-montp2.fr [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Vidussi, Francesca [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Mostajir, Behzad [RESEAUX Team (Reseaux Planctoniques et Changement Environnemental), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc093, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France); Centre d' ecologie marine experimentale MEDIMEER (Mediterranean centre for Marine Ecosystem Experimental Research), Universite Montpellier 2-CNRS (UMS 3301), Station Mediterraneenne de l' Environnement Littoral, MEDIMEER, 2 Rue des Chantiers, 34200 Sete (France); Charmantier, Guy; Lorin-Nebel, Catherine [AEO Team (Adaptation Ecophysiologique et Ontogenese), UMR 5119 Ecosym UM2, CNRS, IRD, Ifremer, UM1, Universite Montpellier 2, cc092, Pl. Eugene Bataillon, 34095 Montpellier, Cx 05 (France)

    2012-03-15

    Coastal marine ecosystems are submitted to variations of several abiotic and biotic parameters, some of them related to global change. Among them the ultraviolet-B (UV-B) radiation (UVBR: 280-320 nm) may strongly impact planktonic fish larvae. The consequences of an increase of UVBR on the osmoregulatory function of Dicentrarchus labrax larvae have been investigated in this study. In young larvae of D. labrax, as in other teleosts, osmoregulation depends on tegumentary ion transporting cells, or ionocytes, mainly located on the skin of the trunk and of the yolk sac. As early D. labrax larvae passively drift in the top water column, ionocytes are exposed to solar radiation. The effect of UVBR on larval osmoregulation in seawater was evaluated through nanoosmometric measurements of the blood osmolality after exposure to different UV-B treatments. A loss of osmoregulatory capability occured in larvae after 2 days of low (50 {mu}W cm{sup -2}: 4 h L/20 h D) and medium (80 {mu}W cm{sup -2}: 4 h L/20 h D) UVBR exposure. Compared to control larvae kept in the darkness, a significant increase in blood osmolality, abnormal behavior and high mortalities were detected in larvae exposed to UVBR from 2 days on. At the cellular level, an important decrease in abundance of tegumentary ionocytes and mucous cells was observed after 2 days of exposure to UVBR. In the ionocytes, two major osmoeffectors were immunolocalized, the Na{sup +}/K{sup +}-ATPase and the Na{sup +}/K{sup +}/2Cl{sup -} cotransporter. Compared to controls, the fluorescent immunostaining was lower in UVBR-exposed larvae. We hypothesize that the impaired osmoregulation in UVBR-exposed larvae originates from the lower number of tegumentary ionocytes and mucous cells. This alteration of the osmoregulatory function could negatively impact the survival of young larvae at the surface water exposed to UVBR.

  12. The occurrence of digenean larvae in freshwater snails at Mbezi ...

    African Journals Online (AJOL)

    The occurrence of digenean larvae in freshwater snails at Mbezi-Temboni pond, Dar es Salaam. ESP Kigadye, G Nkwengulila. Abstract. The abundance of digenean larvae in snails at a pond in Mbezi-Temboni, Dar es Salaam, was investigated from July 1996 to June 1997. A total of 2,112 snails belonging to three species, ...

  13. Infectivity and development of X-irradiated third-stage larvae of Angiostrongylus cantonensis in rats

    International Nuclear Information System (INIS)

    Fujiu, Yoshinori

    1989-01-01

    Angiostrongylus cantonensis third-stage larvae were exposed to less than 10Krad of X-radiation and then given orally to white rats to examine the effects of X-radiation on infectivity and development of the irradiated third-stage larvae and on fecundity of adults developing from the irradiated third-stage larvae. The deleterious effects of X-radiation were observed at relatively lower dosage in the above three parameters. A degree in susceptibility on X-radiation was shown to be radiation-dose-dependent. Comparing to the irradiation of larvae in vitro, the irradiation of larvae in snails caused less deleterious effects at the same dose of X-irradiation. Application of X-radiation to food hygiene was also discussed. (author)

  14. Nursing protects honeybee larvae from secondary metabolites of pollen.

    Science.gov (United States)

    Lucchetti, Matteo A; Kilchenmann, Verena; Glauser, Gaetan; Praz, Christophe; Kast, Christina

    2018-03-28

    The pollen of many plants contains toxic secondary compounds, sometimes in concentrations higher than those found in the flowers or leaves. The ecological significance of these compounds remains unclear, and their impact on bees is largely unexplored. Here, we studied the impact of pyrrolizidine alkaloids (PAs) found in the pollen of Echium vulgare on honeybee adults and larvae. Echimidine, a PA present in E. vulgare pollen, was isolated and added to the honeybee diets in order to perform toxicity bioassays. While adult bees showed relatively high tolerance to PAs, larvae were much more sensitive. In contrast to other bees, the honeybee larval diet typically contains only traces of pollen and consists predominantly of hypopharyngeal and mandibular secretions produced by nurse bees, which feed on large quantities of pollen-containing bee bread. We quantified the transfer of PAs to nursing secretions produced by bees that had previously consumed bee bread supplemented with PAs. The PA concentration in these secretions was reduced by three orders of magnitude as compared to the PA content in the nurse diet and was well below the toxicity threshold for larvae. Our results suggest that larval nursing protects honeybee larvae from the toxic effect of secondary metabolites of pollen. © 2018 The Authors.

  15. Nursing protects honeybee larvae from secondary metabolites of pollen

    Science.gov (United States)

    Lucchetti, Matteo A.; Kilchenmann, Verena; Glauser, Gaetan; Praz, Christophe

    2018-01-01

    The pollen of many plants contains toxic secondary compounds, sometimes in concentrations higher than those found in the flowers or leaves. The ecological significance of these compounds remains unclear, and their impact on bees is largely unexplored. Here, we studied the impact of pyrrolizidine alkaloids (PAs) found in the pollen of Echium vulgare on honeybee adults and larvae. Echimidine, a PA present in E. vulgare pollen, was isolated and added to the honeybee diets in order to perform toxicity bioassays. While adult bees showed relatively high tolerance to PAs, larvae were much more sensitive. In contrast to other bees, the honeybee larval diet typically contains only traces of pollen and consists predominantly of hypopharyngeal and mandibular secretions produced by nurse bees, which feed on large quantities of pollen-containing bee bread. We quantified the transfer of PAs to nursing secretions produced by bees that had previously consumed bee bread supplemented with PAs. The PA concentration in these secretions was reduced by three orders of magnitude as compared to the PA content in the nurse diet and was well below the toxicity threshold for larvae. Our results suggest that larval nursing protects honeybee larvae from the toxic effect of secondary metabolites of pollen. PMID:29563265

  16. Structure of recombinant human carboxylesterase 1 isolated from whole cabbage looper larvae

    International Nuclear Information System (INIS)

    Greenblatt, Harry M.; Otto, Tamara C.; Kirkpatrick, Melanie G.; Kovaleva, Elena; Brown, Susan; Buchman, George; Cerasoli, Douglas M.; Sussman, Joel L.

    2012-01-01

    Large quantities of recombinant human carboxylesterase 1 have been produced in an economical whole insect larvae system. The crystal structure of this enzyme is essentially identical to that produced by cell culture techniques. The use of whole insect larvae as a source of recombinant proteins offers a more cost-effective method of producing large quantities of human proteins than conventional cell-culture approaches. Human carboxylesterase 1 has been produced in and isolated from whole Trichoplusia ni larvae. The recombinant protein was crystallized and its structure was solved to 2.2 Å resolution. The results indicate that the larvae-produced enzyme is essentially identical to that isolated from cultured Sf21 cells, supporting the use of this expression system to produce recombinant enzymes for crystallization studies

  17. First record of Naushonia sp. (Decapoda: Laomediidae) larva from the Equatorial Atlantic.

    Science.gov (United States)

    De Albuquerque Lira, Simone Maria; De Santana, Claudeilton Severino; Schwamborn, Ralf

    2018-02-26

    The first zoeal-stage larva of a possibly new species of mud shrimp Naushonia (Decapoda: Gebiidea: Laomediidae) was described from plankton samples taken off the Fernando de Noronha Archipelago, being the first occurrence at the oceanic islands of the Equatorial Atlantic. Five zoea I larvae were obtained and dissected for observation of mouthparts. This zoea I of Naushonia sp. is well distinguished from the first larvae of N. portoricensis (Rathbun 1901) from the Caribbean and N. cangronoides (Kingsley 1897) from the Northwest Atlantic in terms of development and setation of appendages, and possibly belongs to a new, undescribed species. The present study widens the knowledge on tropical oceanic decapod larvae and provides detailed drawings and new photographic illustrations with extended depth of field of these organisms.

  18. An improved brine shrimp larvae lethality microwell test method.

    Science.gov (United States)

    Zhang, Yi; Mu, Jun; Han, Jinyuan; Gu, Xiaojie

    2012-01-01

    This article described an improved brine shrimp larvae lethality microwell test method. A simply designed connecting vessel with alternative photoperiod was used to culture and collect high yield of active Artemia parthenogenetica nauplii for brine shrimp larvae lethality microwell test. Using this method, pure A. parthenogenetica nauplii suspension was easily cultured and harvested with high density about 100-150 larvae per milliliter and the natural mortality was reduced to near zero by elimination of unnecessary artificial disturbance. And its sensitivity was validated by determination of LC(50)-24 h of different reference toxicants including five antitumor agents, two pesticides, three organic pollutants, and four heavy metals salts, most of which exhibited LC(50)-24 h between 0.07 and 58.43 mg/L except for bleomycin and mitomycin C with LC(50)-24 h over 300 mg/L.

  19. [Effects of fermented cattle dung on the growth and development of Tenebrio molitor larvae].

    Science.gov (United States)

    Zeng, Xiang-Wei; Wang, Xia; Guo, Li-Yue; Zhan, Li-Jie; Bo, Wen-Jing; Li, Zhan; Wu, Guang-Lei; Jiang, Gao-Ming

    2012-07-01

    In order to make use of and industrialize the animal dung from large cattle farms, this paper explored the feasibility of using Tenebrio molitor to digest and utilize cattle dung. Cattle dung was mixed with the conventional feed (65% wheat bran, 30% corn flour, and 5% bean pulp) of T. molitor in definite proportions, and fermented with effective microorganisms (EM). The fermented products containing 60% and 80% of cattle dung (FD1 and FD2, respectively) were selected to feed T. molitor larvae, and the effects of the fermented products on the growth curve, death rate, pupation rate, and antioxidant system of the larvae were compared. Compared with CK (conventional deed), the FD1 made the developmental duration of the larvae prolonged by 10 days and the larvae's death rate upraised somewhat, but made the single larva's total food intake, average body mass, crude fat content, and ratio of unsaturated to saturated fat acids increased by 49%, 28%, 26%, and 32%, respectively (P molitor larvae had weak adaptability to FD2. Our findings suggested that using FD1 to feed the 3rd instar of T. molitor larvae would have good practical prospects in industrializing cattle dung.

  20. Modulation of nutrient composition of black soldier fly (Hermetia illucens larvae by feeding seaweed-enriched media.

    Directory of Open Access Journals (Sweden)

    Nina S Liland

    Full Text Available Black soldier fly (Hermetia illucens larvae are a promising source of protein and lipid for animal feeds. The nutritional composition of the BSF larvae depend partly on the composition of the feeding medium. The BSF lipid profile in part mimics the feeding media lipid profile, and micronutrients, like minerals and vitamins, can readily accumulate in black soldier fly larvae. However, investigative studies on bioconversion and accumulation of nutrients from media to black soldier fly larvae are scarce. Here we show that inclusion of the brown algae Ascophyllum nodosum in the substrate for black soldier fly larvae can introduce valuable nutrients, commonly associated with the marine environment, into the larvae. The omega-3 fatty acid eicosapentaenoic acid (20:5n-3, iodine and vitamin E concentrations increased in the larvae when more seaweed was included in the diet. When the feeding media consisted of more than 50% seaweed, the larvae experienced poorer growth, lower nutrient retention and lower lipid levels, compared to a pure plant based feeding medium. Our results confirm the plasticity of the nutritional make-up of black soldier fly larvae, allowing it to accumulate both lipid- and water-soluble compounds. A broader understanding of the effect of the composition of the feeding media on the larvae composition can help to tailor black soldier fly larvae into a nutrient profile more suited for specific feed or food purposes.

  1. Biological Role of Paenilarvins, Iturin-Like Lipopeptide Secondary Metabolites Produced by the Honey Bee Pathogen Paenibacillus larvae.

    Science.gov (United States)

    Hertlein, Gillian; Seiffert, Marlene; Gensel, Sebastian; Garcia-Gonzalez, Eva; Ebeling, Julia; Skobalj, Ranko; Kuthning, Anja; Süssmuth, Roderich D; Genersch, Elke

    2016-01-01

    The Gram-positive bacterium Paenibacillus larvae (P. larvae) is the causative agent of a deadly honey bee brood disease called American Foulbrood (AFB). AFB is a notifiable epizootic in most countries and, hence, P. larvae is of considerable relevance for veterinarians and apiculturists alike. Over the last decade, much progress has been made in the understanding of the (patho)biology of P. larvae. Recently, several non-ribosomally produced peptides (NRP) and peptide/polyketide (NRP/PK) hybrids produced by P. larvae were identified. Among these NRPs were iturin-like lipopeptides, the paenilarvins A-C. Iturins are known to exhibit strong anti-fungal activity; for some iturins, cytotoxic activity towards mammalian erythrocytes and human cancer cell lines are described. We here present our results on the analysis of the natural function of the paenilarvins during pathogenesis of P. larvae infections. We demonstrated production of paenilarvins in infected larvae. However, we could neither demonstrate cytotoxicity of paenilarvins towards cultured insect cells nor towards larvae in feeding assays. Accordingly, exposure bioassays performed with larvae infected by wild-type P. larvae and a knockout mutant of P. larvae lacking production of paenilarvins did not substantiate a role for the paenilarvins as virulence factor. Further experiments are necessary to analyze the relevance of the paenilarvins' anti-fungal activity for P. larvae infections in the presence of fungal competitors in the larval midgut or cadaver.

  2. Composting poultry manure by fly larvae (Musca domestica) eliminates Campylobacter jejuni from the manure

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Hald, Birthe

    2013-01-01

    study To monitor fly larvae composting of poultry manure artificially contaminated with C. jejuni, and to investigate a possible transmission route of C. jejuni from the manure through the fly larvae to the adult fly. Conclusions The addition of fly larvae both accelerated the degradation of manure...

  3. Use of liquid nitrogen and albendazole in successfully treating cutaneous larva migrans.

    Science.gov (United States)

    Kapadia, Naseema; Borhany, Tasneem; Farooqui, Maria

    2013-05-01

    To determine the efficacy of combination treatment of Albendazole along with liquid nitrogen in cutaneous larva migrans. Quasi-experimental study. Abbasi Shaheed Hospital and The Aga Khan Hospital, Karachi, from December 2008 to December 2010. Eighteen cases of cutaneous larva migrans were collected and divided into two groups. Group-A was administered oral Albendazole 400 mg once per day along with topical steroid and oral cetrizine 10 mg once at night for 7 days. Group-B also received oral Albendazole 400 mg once per day along with cetrizine 10 mg once at night but they also received single application of liquid nitrogen to freeze the larva. It was found that in Group-A only 2 out of 9 (22%) showed improvement whereas 78% had to be given liquid nitrogen cryotherapy 3 - 7 days after Albendazole to prevent migration of larva. In Group-B, the improvement was 100% and all 9 patients were successfully treated. Use of liquid nitrogen along with oral anti-helminths is very effective in treating cutaneous larva migrans than Albendazole alone.

  4. Performance of jundiá larvae, Rhamdia quelen, fed on probiotic supplemented diets

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    Vilson Borba Pinto

    2015-08-01

    Full Text Available Since probiotics have proved to be a viable alternative to antibiotics as enhancers of animal growth, the performance, uniformity and mortality rates of the jundiá (Rhamdia quelen larvae fed on diets with different probiotics were evaluated. Jundiá larvae, aged four days post hatching, were fed during 21 days with the following diets, in four replicates, namely, CO: control feed, without probiotics; PP: feed with Pichia pastoris; SB: feed with Saccharomyces boulardii; BT: feed with Bacillus cereus var. toyoi. Among the tested probiotic, Bacillus cereus var. toyoi had the best results due to the fact that the larvae were 25% heavier than CO at the end of the first week; the difference increased to 28% by the end of the trial. Further, BT also improved uniformity and Fulton’s condition factor. Larvae fed on Saccharomyces boulardii had the lowest body weight, whereas those fed on Pichia pastoris grew similarly to the control diet. Mortality rate was not affected by treatments. Bacillus cereus var. toyoi improves the performance and uniformity of the larvae, but does not affect mortality rate.

  5. Food web changes under ocean acidification promote herring larvae survival.

    Science.gov (United States)

    Sswat, Michael; Stiasny, Martina H; Taucher, Jan; Algueró-Muñiz, Maria; Bach, Lennart T; Jutfelt, Fredrik; Riebesell, Ulf; Clemmesen, Catriona

    2018-05-01

    Ocean acidification-the decrease in seawater pH due to rising CO 2 concentrations-has been shown to lower survival in early life stages of fish and, as a consequence, the recruitment of populations including commercially important species. To date, ocean-acidification studies with fish larvae have focused on the direct physiological impacts of elevated CO 2 , but largely ignored the potential effects of ocean acidification on food web interactions. In an in situ mesocosm study on Atlantic herring (Clupea harengus) larvae as top predators in a pelagic food web, we account for indirect CO 2 effects on larval survival mediated by changes in food availability. The community was exposed to projected end-of-the-century CO 2 conditions (~760 µatm pCO 2 ) over a period of 113 days. In contrast with laboratory studies that reported a decrease in fish survival, the survival of the herring larvae in situ was significantly enhanced by 19 ± 2%. Analysis of the plankton community dynamics suggested that the herring larvae benefitted from a CO 2 -stimulated increase in primary production. Such indirect effects may counteract the possible direct negative effects of ocean acidification on the survival of fish early life stages. These findings emphasize the need to assess the food web effects of ocean acidification on fish larvae before we can predict even the sign of change in fish recruitment in a high-CO 2 ocean.

  6. Temporal variability of fish larvae assemblages: influence of natural and anthropogenic disturbances

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    David A. Reynalte-Tataje

    Full Text Available Natural and induced disturbances greatly influence the temporal distribution of ichthyoplankton abundance. This study assesses and compares the temporal variability of fish larvae assemblages in controlled and free environments to determine the influence of environment variables on the main taxa in these systems. The study was conducted at the Chapecó (without dam impact and Ligeiro (with dam impact river mouths, which are located in the upper Uruguay River. Samples were made between October 2001 and March 2004 during three reproductive periods. The larvae assemblages were composed of small and medium-sized Characiformes and Siluriformes. The variation in the distribution of larvae was mainly temporal (>85%. When the three reproductive periods were compared, it was observed in the second period, characterized by a larger water flow and a lower temperature, that there was a reduction in abundance, a lower number of taxa, an absence of stages in post-flexion and a high dissimilarity in larvae assemblage structure. In general, the environmental variables of water flow and temperature most influenced the distribution of egg and larvae abundance. In the studied area, a smaller temporal variability was observed in the structure of larvae assemblages at the sampling sites in the Chapecó River mouth than in in the Ligeiro River mouth under the influence of dams.

  7. Caffeine taste signaling in Drosophila larvae

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    Anthi A Apostolopoulou

    2016-08-01

    Full Text Available The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal and ventral organ. However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative coreceptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s. This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviours.

  8. Keragaman Genetik Metarhizium anisopliae dan Virulensinya pada Larva Kumbang Badak (Oryctes rhinoceros

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    Aisyah Surya Bintang

    2015-07-01

    Full Text Available Rhinoceros beetle (Oryctes rhinoceros is one of the important pests of coconut tree. One of eco-friendly control applied for this pest is by using entomopathogenic fungiMetarhizium anisopliae. There is not much information about the variability and virulence of M. anisopliae toward O. rhinoceros. M. anisopliae isolates obtained from Biological Control Laboratory, Faculty of Agriculture, Universitas Gadjah Mada were cultured on PDA medium.M. anisopliae isolates was isolated from O. rhinoceros larvae (MaOr, Lepidiota stigma larvae (MaLs, Brontispa longissima beetle (MaBl.O. rhinoceros beetles were obtained from Kulon Progo, DIY. This study used molecular test, and virulence test toward 3rd stadium of O. rhinoceros larvae by using dipping method. Molecular test by sequence and phylogenetic analysis, showed that MaOr was located at different group (out group with MaLs and MaBr. On the density 107 conidium/ml MaOr and MaLs were more virulent than MaBl towards 3rd stadium of O. rhinoceros larvae. INTISARI Kumbang badak (Oryctes rhinoceros merupakan salah satu hama penting pada tanaman kelapa. Salah satu upaya pengendalian yang ramah lingkungan adalah dengan menggunakan jamur entomopatogen, yakni Metarhizium anisopliae. Belum banyak diketahui mengenai keragaman dan juga virulensi dari M. anisopliae terhadap O. rhinoceros. Tujuan dari penelitian ini adalah untuk mengetahui keragaman genetik M. anisopliae dan virulensinya pada larva kumbang badak. Isolat yang digunakan berasal dari Laboratorium Pengendalian Hayati, Fakultas Pertanian, Universitas Gadjah Mada dalam bentuk kultur murni pada medium PDA. Isolat yang gunakan diisolasi dari larvaOryctes rhinoceros (MaOr, larva Lepidiota stigma (MaLs, dan kumbang Brontispa longissima (MaBl. Serangga yang diuji berasal dari daerah Kulon Progo, DIY. Pengujian secara molekuler dengan analisis sekuensing dan filogenetik, menunjukkan bahwa isolat MaOr terletak pada grup yang berbeda dengan MaLs dan Ma

  9. Riceland mosquito management practices for Anopheles quadrimaculatus larvae.

    Science.gov (United States)

    Allen, R A; Wilkes, W W; Lewis, C N; Meisch, M V

    2008-12-01

    Two separate but related studies were conducted regarding management of Anopheles quadrimaculatus larval populations in commercial rice fields near Cleveland, MS, in 2004. Study 1 was to evaluate the effectiveness of 2 treatments of aerially applied ultra-low volume applications of Bacillus thuringiensis var. israelensis (Bti) against An. quadrimaculatus larvae in dense, high-canopy mid- to late-season rice crop. Study 2 was to investigate the effect of preflood treatments of lambda-cyhalothrin (Karate), which is commonly used against rice water weevil (Lissorhoptrus oryzophilus), on An. quadrimaculatus larvae. Excellent initial, but short residual control (>99% control 1 day after treatment) was observed in the Bti-treated fields in both mid- and late-season rice. Little or no effect on mosquito larvae was observed in the lambda-cyhalothrin-treated fields. Results indicate that Bti can be effectively used by mosquito management personnel to control larval populations of An. quadrimaculatus in late-season rice fields; however, lambda-cyhalothrin did not effectively control larval An. quadrimaculatus when applied preflood to rice fields.

  10. BIOLARVASIDA EKSTRAK ETANOL KULIT NANAS (Ananas comosus L. Merr TERHADAP LARVA NYAMUK Culex Sp.

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    Siti Juariah

    2017-10-01

    Full Text Available ABSTRAK   Nanas merupakan salah satu komoditi asal Provinsi Riau. Setiap tahun nanas mengalami peningkatan dengan semakin meningkatnya produksi nanas maka limbah yang dihasilkan akan semakin meningkat. Pada limbah kulit nanas diduga terdapat senyawa alkaloid yang dapat membunuh larva nyamuk Culex Sp. Nyamuk yang termasuk dalam genus Culex dikenal sebagai vektor penular arbovirus, demam kaki gajah, dan malaria pada unggas. Pengendalian serangga umumnya dilakukan menggunakan pestisida sintetik. Penggunaan senyawa kimia yang bersifat sintetik sangat berbahaya bagi pengguna yang terpajan. Tujuan dari penelitian ini adalah untuk menentukan efektifitas ekstrak etanol kulit nanas dan mengetahui jumlah larva yang mati dengan menentukan konsentrasi terbaik dari ekstrak etanol kulit nanas (AnanascomosusL. terhadap larva nyamuk culex Sp. Penelitian ini bersifat Eksperimen Laboratory, yaitu meneliti tentang uji mortalitas larva nyamuk Culex Sp setelah pemberian ekstrak etanol kulit nanas (AnanascomosusL.. Hasil penelitian yang didapatkan bahwa ekstrak etanol kulit nanas dapat dibuktikan pada tingkat konsentrasi 1% angka kematian larva nyamuk telah mencapai 72,5%. Sedangkan pada konsentrasi 4% telah mampu membunuh larva sebesar 97,5%. Kata Kunci        : Ekstraketanol, Kulit nanas, Culex Sp.   ABSTRACT                Pineapple is one of the commodities origin of Riau Province. Each year the pineapple increases with the increasing production of pineapple so the waste generated will increase. In pineapple leaf waste is suspected of alkaloid compounds that can kill the mosquito larvae Culex Sp. The mosquitoes belonging to the genus Culex are known as arbovirus-transmitting vectors, elephant leg fever, and malaria in poultry. Insect control is generally done using synthetic pesticides. The use of synthetic chemicals is very dangerous for exposed users. The purpose of this study was to determine the effectiveness of pineapple ethanol

  11. Hemocyte quantitative changes in Anticarsia gemmatalis (Lepidoptera: Noctuidae larvae infected by AgMNPV

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    Fábio Goulart de Andrade

    2010-04-01

    Full Text Available The initial effects of the infection by AgMNPV in the total and differential counts of the hemocytes in Anticarsia gemmatalis (Lepidoptera: Noctuidae larvae were studied. The total number of the hemocytes did not decrease in infected larvae, as it occurred in non infected larvae. In infected larvae, the hemocyte types showed the following frequencies: plasmatocytes - 47.8%, esferulocytes - 25.9%, granulocytes - 15.8%, oenocytoids - 7.2%, prohemocytes - 2.8%, vermicytes - 0,5%. Only the percentage of the granulocytes was different among infected and non infected larvae, indicating that these cells responded quickly to the initial viral infection. These results showed the effective role of the hemocytes in the response of the A. gemmatalis to the infection by AgMNPV. The comprehension of the immunological mechanisms of this insect is an important tool to understand its biological control.Os efeitos iniciais da infecção por AgMNPV nas contagens total e diferencial dos hemócitos em Anticarsia gemmatalis (Lepidoptera: Noctuidae foram estudados. O número total de hemócitos não diminuiu nas larvas infectadas, como ocorreu nas larvas não infectadas. Nas larvas infectadas, os tipos de hemócitos apresentaram as seguintes freqüências: plasmatócitos - 47,8%, esferulócitos - 25,9%, granulócitos - 15,8%, oenocitóides - 7,2%, prohemócitos - 2,8%, vermiformes - 0,5%. Apenas a porcentagem de granulócitos foi diferente entre larvas infectadas e não infectadas, indicando que estas células responderam rapidamente à infecção viral inicial. Estes resultados mostraram o papel efetivo que dos hemócitos na resposta de A. gemmatalis à infecção por AgMNPV. A compreensão dos mecanismos imunológicos deste inseto é uma ferramenta importante para compreender seu controle biológico.

  12. Toxocara cati larvae in the eye of a child: a case report

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    Mohammad Zibaei

    2014-05-01

    Full Text Available Toxocariasis is a consequence of human infection by Toxocara larvae. There are symptomatic (visceral, ocular and asymptomatic course of toxocariasis. The ocular form is very rare. We present a 6-year-old patient who developed an ocular form of toxocariasis caused by Toxocara cati. He demonstrated lesions in the peripheral retina of the right eye. White granuloma was present in the superior peripheral retina. A positive immunological assay for toxocariasis essentially completed the outcomes. On the basis of clinical manifestations and conducted examinations, a diagnosis of ocular form of toxocariasis was established. Albendazole and corticosteroids were applied in treatment. Current results clearly highlight the usefulness of excretory-secretory antigens derived from larvae of Toxocara cati for the fine diagnosis ocular larva migrans caused by Toxocara larvae.

  13. Sensory Flask Cells in Sponge Larvae Regulate Metamorphosis via Calcium Signaling.

    Science.gov (United States)

    Nakanishi, Nagayasu; Stoupin, Daniel; Degnan, Sandie M; Degnan, Bernard M

    2015-12-01

    The Porifera (sponges) is one of the earliest phyletic lineages to branch off the metazoan tree. Although the body-plan of sponges is among the simplest in the animal kingdom and sponges lack nervous systems that communicate environmental signals to other cells, their larvae have sensory systems that generate coordinated responses to environmental cues. In eumetazoans (Cnidaria and Bilateria), the nervous systems of larvae often regulate metamorphosis through Ca(2+)-dependent signal transduction. In sponges, neither the identity of the receptor system that detects an inductive environmental cue (hereafter "metamorphic cues") nor the signaling system that mediates settlement and metamorphosis are known. Using a combination of behavioral assays and surgical manipulations, we show here that specialized epithelial cells-referred to as flask cells-enriched in the anterior third of the Amphimedon queenslandica larva are most likely to be the sensory cells that detect the metamorphic cues. Surgical removal of the region enriched in flask cells in a larva inhibits the initiation of metamorphosis. The flask cell has an apical sensory apparatus with a cilium surrounded by an apical F-actin-rich protrusion, and numerous vesicles, hallmarks of eumetazoan sensory-neurosecretory cells. We demonstrate that these flask cells respond to metamorphic cues by elevating intracellular Ca(2+) levels, and that this elevation is necessary for the initiation of metamorphosis. Taken together, these analyses suggest that sponge larvae have sensory-secretory epithelial cells capable of converting exogenous cues into internal signals via Ca(2+)-mediated signaling, which is necessary for the initiation of metamorphosis. Similarities in the morphology, physiology, and function of the sensory flask cells in sponge larvae with the sensory/neurosecretory cells in eumetazoan larvae suggest this sensory system predates the divergence of Porifera and Eumetazoa. © The Author 2015. Published by Oxford

  14. Chemically mediated group formation in soil-dwelling larvae and pupae of the beetle Trypoxylus dichotomus

    Science.gov (United States)

    Kojima, Wataru; Ishikawa, Yukio; Takanashi, Takuma

    2014-09-01

    Many insects form groups through interactions among individuals, and these are often mediated by chemical, acoustic, or visual cues and signals. In spite of the diversity of soil-dwelling insects, their aggregation behaviour has not been examined as extensively as that of aboveground species. We investigated the aggregation mechanisms of larvae of the Japanese rhinoceros beetle Trypoxylus dichotomus, which live in groups in humus soil. In two-choice laboratory tests, 2nd- and 3rd-instar larvae gathered at conspecific larvae irrespective of the kinship. The ablation of maxillae, which bear chemosensilla, abolished aggregation behaviour. Intact larvae also exhibited aggregation behaviour towards a larval homogenate. These results suggest that larval aggregation is mediated by chemical cues. We also demonstrated that the mature larvae of T. dichotomus built their pupal cells close to a mesh bag containing a conspecific pupal cell, which indicated that larvae utilize chemical cues emanating from these cells to select the pupation site. Thus, the larvae of T. dichotomus may use chemical cues from the conspecifics in two different contexts, i.e. larval aggregation and pupation site selection. Using conspecific cues, larvae may be able to choose suitable locations for foraging or building pupal cells. The results of the present study highlight the importance of chemical information in belowground ecology.

  15. Biophysical processes leading to the ingress of temperate fish larvae into estuarine nursery areas: A review

    Science.gov (United States)

    Teodósio, Maria Alexandra; Paris, Claire B.; Wolanski, Eric; Morais, Pedro

    2016-12-01

    A series of complementary hypotheses have been proposed to explain the recruitment of marine and temperate pelagic fish larvae originated from pelagic eggs in coastal environments. In this review, we propose a new and complementary hypothesis describing the biophysical processes intervening in the recruitment of temperate fish larvae into estuaries. This new hypothesis, the Sense Acuity And Behavioral (SAAB) hypothesis, recognizes that recruitment is unlikely if the larvae drift passively with the water currents, and that successful recruitment requires the sense acuity of temperate fish larvae and their behavioral response to the estuarine cues present in coastal areas. We propose that temperate fish larvae use a hierarchy of sensory cues (odor, sound, visual and geomagnetic cues) to detect estuarine nursery areas and to aid during navigation towards these areas. The sensorial acuity increases along ontogeny, which coincides with increased swimming capabilities. The swimming strategies of post-flexion larvae differ from offshore areas to the tidal zone. In offshore areas, innate behavior might lead larvae towards the coast guided by a sun compass or by the earth's geomagnetic field. In areas under limited influence of estuarine plumes (either in energetic nearshore areas or offshore), post-flexion larvae display a searching swimming behavior for estuarine disconnected patches (infotaxis strategy). After finding an estuarine plume, larvae may swim along the increasing cue concentration to ingress into the estuary. Here, larvae exhibit a rheotaxis behavior and avoid displacement by longshore currents by keeping bearing during navigation. When larvae reach the vicinity of an estuary, merging diel rhythms with feeding and predator avoidance strategies with tidally induced movements is essential to increase their chances of estuarine ingress. A fish larva recruitment model developed for the Ria Formosa lagoon supports the general framework of the SAAB hypothesis. In

  16. Controle de larvas de Boophilus microplus por Metarhizium anisopliae em pastagens infestadas artificialmente Control of Boophilus microplus larvae by Metarhizium anisopliae in artificially infested pastures

    Directory of Open Access Journals (Sweden)

    Lúcia Mara de Souza Basso

    2005-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência do controle exercido por Metarhizium anisopliae na população de Boophilus microplus, em pastagens de Brachiaria brizantha, e do híbrido Tifton 85 (Cynodon spp., artificialmente infestadas com fêmeas ingurgitadas do carrapato. Trinta canteiros com 1 m² de área cada foram distribuídos aleatoriamente. Quinze foram pulverizados com esporos do fungo e quinze controles em cada forrageira, constituindo cinco repetições de cada tratamento, foram infestados com número e peso padronizados de fêmeas ingurgitadas do ácaro. Aplicou-se o fungo, na concentração de 1,8x10(8 conídios mL-1, em três situações: pulverização antes da infestação com o carrapato, após a infestação e posterioriormente à emergência das primeiras larvas nos capins. A ação do fungo foi avaliada no 35º, 38º, 41º, 48º, 55º e 61º dia pós-infestação, por meio da contagem de larvas recuperadas. Obteve-se controle de larvas do ácaro, que, nas avaliações realizadas entre o 35º e o 48º dia pós-infestação, variou entre 87% e 94%. As médias das contagens de estágios larvares do carrapato foram menores em todas as amostragens realizadas no capim-Tifton 85, indicando que houve efeito da pastagem na ação do fungo. A situação de aplicação influencia a atividade do fungo, com melhor resultado nas coletas realizadas entre o 41º e 55º dia após infestação em B. brizantha, e aplicação dos conídios logo após a emergência das primeiras larvas.The objective of this work was to evaluate the efficiency of Metarhizium anisopliae fungus against Boophilus microplus population in Brachiaria brizantha and Tifton 85 (Cynodon pastures, artificially infested with tick engorged females. Thirty plots of 1 m² each were randomly distributed in fifteen treated and fifteen control groups per type of grass, establishing five repetitions for each treatment. Pastures were infested with engorged tick females

  17. Thermal ecology of gregarious and solitary nettle-feeding nymphalid butterfly larvae.

    Science.gov (United States)

    Bryant, S R; Thomas, C D; Bale, J S

    2000-01-01

    Group-living in animal populations has many possible ecological and evolutionary explanations, including predator evasion and feeding facilitation. In insects, the thermal balance of solitary and gregarious larvae is likely to differ and may thus have important ecological consequences. The abilities of the larvae of four species of nettle-feeding nymphalid butterflies to thermoregulate were quantified in the field. Larval surface body temperatures of the gregarious Aglais urticae (small tortoiseshell) and Inachis io (peacock) and the solitary Polygonia c-album (comma) and Vanessa atalanta (red admiral) were measured for each instar, in both sunny and overcast conditions, over a seasonal range of temperatures. The results suggested two distinct larval thermal strategies. In the presence of direct sunlight, the exposed gregarious larvae of A. urticae and I. io regulated body temperatures at 32.5 and 31.5°C, respectively, while the temperatures of concealed larvae of P. c-album and V. atalanta were largely dependent on ambient temperatures. In the sun, the range of body temperatures recorded for A. urticae and I. io larvae was fairly narrow relative to ambient temperatures. This suggests a high degree of thermal control in these species. Modal body temperatures coincided with the temperature at which development rate is maximal. Regardless of whether changes in thermoregulation are a cause or consequence of the evolution of gregariousness, the combination of behavioural thermoregulation and gregariousness in larval insects has important implications for voltinism patterns and range extension (via increased development rates). Distributional responses of gregarious and solitary larvae to climatic warming may differ as a result of changes in cloud cover as well as changes in temperature.

  18. Extreme morphologies of mantis shrimp larvae

    DEFF Research Database (Denmark)

    Haug, Carolin; Ahyong, Shane T.; Wiethase, Joris H.

    2016-01-01

    Larvae of stomatopods (mantis shrimps) are generally categorized into four larval types: antizoea, pseudozoea (both representing early larval stages), alima and erichthus (the latt er two representing later larval stages). These categories, however, do not refl ect the existing morphological...

  19. Two alternating motor programs drive navigation in Drosophila larva.

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    Subhaneil Lahiri

    Full Text Available When placed on a temperature gradient, a Drosophila larva navigates away from excessive cold or heat by regulating the size, frequency, and direction of reorientation maneuvers between successive periods of forward movement. Forward movement is driven by peristalsis waves that travel from tail to head. During each reorientation maneuver, the larva pauses and sweeps its head from side to side until it picks a new direction for forward movement. Here, we characterized the motor programs that underlie the initiation, execution, and completion of reorientation maneuvers by measuring body segment dynamics of freely moving larvae with fluorescent muscle fibers as they were exposed to temporal changes in temperature. We find that reorientation maneuvers are characterized by highly stereotyped spatiotemporal patterns of segment dynamics. Reorientation maneuvers are initiated with head sweeping movement driven by asymmetric contraction of a portion of anterior body segments. The larva attains a new direction for forward movement after head sweeping movement by using peristalsis waves that gradually push posterior body segments out of alignment with the tail (i.e., the previous direction of forward movement into alignment with the head. Thus, reorientation maneuvers during thermotaxis are carried out by two alternating motor programs: (1 peristalsis for driving forward movement and (2 asymmetric contraction of anterior body segments for driving head sweeping movement.

  20. Successful determination of larval dispersal distances and subsequent settlement for long-lived pelagic larvae.

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    Pelayo Salinas-de-León

    Full Text Available Despite its importance, we still have a poor understanding of the level of connectivity between marine populations in most geographical locations. Taking advantage of the natural features of the southeast coast of New Zealand's North Island, we deployed a series of settlement stations and conducted plankton tows to capture recent settlers and planktonic larvae of the common intertidal gastropod Austrolittorina cincta (6-8 week larval period. Satellite image analysis and ground truthing surveys revealed the absence of suitable intertidal rocky shore habitat for A. cincta over a 100 km stretch of coastline between Kapiti Island to the south and Wanganui to the north. Fifteen settlement stations (3 replicates × 5 sites, which were used to mimic intertidal habitat suitable for A. cincta, were deployed for two months around and north of Kapiti Island (at 0.5, 1, 5, 15, 50 km. In addition, we also conducted plankton tows at each settlement station when the stations were first deployed to collect A. cincta larvae in the water column. On collection, all newly settled gastropods and larvae in the plankton samples were individually isolated, and a species-specific microsatellite marker was used to positively identify A. cincta individuals. Most of the positively identified A. cincta settlers and larvae were collected at the first three sampling stations (<5 km. However, low numbers of A. cincta settlers and larvae were also recorded at the two more distant locations (15 and 50 km. Dispersal curves modeled from our data suggested that <1% of gastropod larvae would travel more than 100 km. While our data show that most larvae are retained close to their natal populations (<5 km, a small proportion of larvae are able to travel much larger geographic distances. Our estimates of larval dispersal and subsequent settlement are one of only a few for marine species with a long-lived larva.

  1. Larva migrans cutánea en Lima. Reporte de 3 casos.

    OpenAIRE

    Legua, Pedro; Guerra, Jorge; Bussalleu, Alejandro

    2014-01-01

    Larva migrans cutánea o “erupción reptante” es una erupción cutánea causada por la migración de la larva de un nemátodo en forma errática en la piel. Ocurre usualmente como resultado de la exposición de la piel a las larvas filariformes infectantes de uncinarias propias de felinos y cánidos, que están presentes en suelos húmedos y arenosos en los que estos animales defecan (playas, jardines, parques, etc.).La larvainfectante no puede completar su ciclo vital en el hospedero humano y entonces ...

  2. Ontogenetic development of attack behaviour by turbot larvae when exposed to copepod prey

    DEFF Research Database (Denmark)

    Højgaard, Jacob K.; Bruno, Eleonora; Støttrup, Josianne Gatt

    2018-01-01

    offered small nauplii (129–202 μm), large nauplii (222–278 μm) and copepodites (342–542 μm), of the calanoid copepod Acartia tonsa. At 8 DPH, turbot larvae had the highest capture success (67%) when offered small nauplii, with a lower capture success of large nauplii (27%) but totally lacked...... by the larva on the copepod was examined, and the approach pattern of the larva was identified as a controlling mechanism for their strike distance, with the initial approach speed of larva at DPH 10 being significantly less than at DPH 8. In all successful attacks, the strike distance was less than 1.17 mm...

  3. Crown-of-Thorns Starfish Larvae Can Feed on Organic Matter Released from Corals

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    Ryota Nakajima

    2016-10-01

    Full Text Available Previous studies have suggested that Crown-of-Thorns starfish (COTS larvae may be able to survive in the absence of abundant phytoplankton resources suggesting that they may be able to utilize alternative food sources. Here, we tested the hypothesis that COTS larvae are able to feed on coral-derived organic matter using labeled stable isotope tracers (13C and 15N. Our results show that coral-derived organic matter (coral mucus and associated microorganisms can be assimilated by COTS larvae and may be an important alternative or additional food resource for COTS larvae through periods of low phytoplankton biomass. This additional food resource could potentially facilitate COTS outbreaks by reducing resource limitation.

  4. Development changes of cuticular hydrocarbons in Chrysomya rufifacies larvae: potential for determining larval age.

    Science.gov (United States)

    Zhu, G H; Ye, G Y; Hu, C; Xu, X H; Li, K

    2006-12-01

    Age determination is the basis of determining the postmortem interval using necrophagous fly larvae. To explore the potential of using cuticular hydrocarbons for determining the ages of fly larvae, changes of cuticular hydrocarbons in developing larvae of Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) were investigated using gas chromatography with flame-ionization detection and gas chromatography-mass spectrometry. This study showed that the larvae produced cuticular hydrocarbons typical of insects. Most of the hydrocarbons identified were alkanes with the carbon chain length of 21-31, plus six kinds of alkenes. The hydrocarbon composition of the larvae correlated with age. The statistical results showed that simple peak ratios of n-C29 divided by another eight selected peaks increased significantly with age; their relationships with age could be modelled using exponential or power functions with R(2) close to or > 0.80. These results suggest that cuticular hydrocarbon composition is a useful indicator for determining the age of larval C. rufifacies, especially for post-feeding larvae, which are difficult to differentiate by morphology.

  5. Use of liquid nitrogen and albendazole in successfully treating cutaneous larva migrans

    International Nuclear Information System (INIS)

    Kapadia, N.; Farooqui, M.; Borhany, T.

    2013-01-01

    Objective: To determine the efficacy of combination treatment of Albendazole along with liquid nitrogen in cutaneous larva migrans. Study Design: Quasi-experimental study. Place and Duration of Study: Abbasi Shaheed Hospital and The Aga Khan Hospital, Karachi, from December 2008 to December 2010. Methodology: Eighteen cases of cutaneous larva migrans were collected and divided into two groups. Group-A was administered oral Albendazole 400 mg once per day along with topical steroid and oral cetrizine 10 mg once at night for 7 days. Group-B also received oral Albendazole 400 mg once per day along with cetrizine 10 mg once at night but they also received single application of liquid nitrogen to freeze the larva. Results: It was found that in Group-A only 2 out of 9 (22%) showed improvement whereas 78% had to be given liquid nitrogen cryotherapy 3 - 7 days after Albendazole to prevent migration of larva. In Group-B, the improvement was 100% and all 9 patients were successfully treated. Conclusion: Use of liquid nitrogen along with oral anti-helminths is very effective in treating cutaneous larva migrans than Albendazole alone. (author)

  6. Abdominal Distension Associated with Luminal Fungi in the Intestines of Axolotl Larvae

    Directory of Open Access Journals (Sweden)

    Chiara Zullian

    2015-01-01

    Full Text Available Axolotls show a remarkable regeneration capacity compared with higher vertebrates, regenerating missing appendages such as limbs and tail as well as other body parts (i.e., apex of the heart, forebrain, and jaw after amputations which makes this animal a very interesting research model for tissue regeneration mechanisms. Larvae are individually housed in a 20% Holtfreter’s solution within clear plastic containers. The photoperiod light : darkness cycle is 12 : 12 h. Larvae with a total body length of less than 5 cm are fed once a day with large brine shrimp and blood worm. Albino larvae appeared to have a tendency to exhibit abdominal distention. No clinical signs of illness seemed to be associated with the condition; however, these animals exhibit a relatively slower growth rate. To better characterize this condition, we performed histological sectioning for cross sectional slide preparation on wild type and albino axolotl larvae following euthanasia. The only lesion seen in the albino larvae was a thickened gut wall and the presence of fungi within the intestines. We hypothesize that this may be due to a lower efficacy of the albino larvae’s immune system.

  7. AKTIVITAS INSEKTISIDA BAGIAN TUMBUHAN CALOPHYLLUM SOULTTRI BURM.F. (CLU IACEAE TERHADAP LARVA LEPIDOPTERA

    Directory of Open Access Journals (Sweden)

    Edy Syahputra

    2014-08-01

    Full Text Available The objective of this test was evaluate the insecticidal activity of ectract of some parts of Calophyllum soulattri (Clusiaceae against larvae of three species of Lepidoptera, i. e Crocidolomia pavonana, Plutella xylostela, and Pieris sp.. Extraction of plant materials was done by infusion method using ethanol. The bioassays were conducted by leaf-feeding method. Second-instar larvae were fed extract-treated broccoli leaves of 48 hours, then they were presented with untreated leaves until the surviving larvae larvae reached the fourth-instar stage. The number of dead larvae was recorded daily an larval mortality date were analyzed by probit method. The result showed the gummy bark exudates and bark extract of old and young C. soulattri plants were highly active against C. pavonana. The abrk extact of old C. soulattri plant was also effective against P. xilostella and Pieris sp. The gummy exudates possessed strong insecticidal activity against C. pavonana larvae with LC50 of 0.04% and prolonged the developmental time from second to fourth instar of C. soulattri 2.03-7.25 days compared with control. The bark excudate gave positive respon to alkaloid flavonoid, and tannin test. Futher studies are needed to identify insecticidal compound in those active extracts.

  8. Distribution and seasonal abundance of carangid larvae in the Arabian sea and Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Peter, K.J.; Balachandran, T.

    Carangid larvae were recorded from 8.8% of the International Indian Ocean Expedition (IIOE) stations in the Arabian Sea and 13.2% in the Bay of Bengal. Their total contribution was 1.1% of the total larvae collected. The highest number of larvae...

  9. Honey bees consider larval nutritional status rather than genetic relatedness when selecting larvae for emergency queen rearing.

    Science.gov (United States)

    Sagili, Ramesh R; Metz, Bradley N; Lucas, Hannah M; Chakrabarti, Priyadarshini; Breece, Carolyn R

    2018-05-16

    In honey bees and many other social insects, production of queens is a vital task, as colony fitness is dependent on queens. The factors considered by honey bee workers in selecting larvae to rear new queens during emergency queen rearing are poorly understood. Identifying these parameters is critical, both in an evolutionary and apicultural context. As female caste development in honey bees is dependent on larval diet (i.e. nutrition), we hypothesized that larval nutritional state is meticulously assessed and used by workers in selection of larvae for queen rearing. To test this hypothesis, we conducted a series of experiments manipulating the nutritional status of one day old larvae by depriving them of brood food for a four-hour period, and then allowing workers to choose larvae for rearing queens from nutritionally deprived and non-deprived larvae. We simultaneously investigated the role of genetic relatedness in selection of larvae for queen rearing. In all the experiments, significantly greater numbers of non-deprived larvae than deprived larvae were selected for queen rearing irrespective of genetic relatedness. Our results demonstrate that honey bees perceive the nutritional state of larvae and use that information when selecting larvae for rearing queens in the natural emergency queen replacement process.

  10. Warming and pCO2 effects on Florida stone crab larvae

    Science.gov (United States)

    Gravinese, Philip M.; Enochs, Ian C.; Manzello, Derek P.; van Woesik, Robert

    2018-05-01

    Greenhouse gas emissions are increasing ocean temperatures and the partial pressure of CO2 (pCO2), resulting in more acidic waters. It is presently unknown how elevated temperature and pCO2 will influence the early life history stages of the majority of marine coastal species. We investigated the combined effect of elevated temperature (30 °C control and 32 °C treatment) and elevated pCO2 (450 μatm control and 1100 μatm treatment) on the (i) growth, (ii) survival, (iii) condition, and (iv) morphology of larvae of the commercially important Florida stone crab, Menippe mercenaria. At elevated temperature, larvae exhibited a significantly shorter molt stage, and elevated pCO2 caused stage-V larvae to delay metamorphosis to post-larvae. On average, elevated pCO2 resulted in a 37% decrease in survivorship relative to the control; however the effect of elevated temperature reduced larval survivorship by 71%. Exposure to both elevated temperature and pCO2 reduced larval survivorship by 80% relative to the control. Despite this, no significant differences were detected in the condition or morphology of stone crab larvae when subjected to elevated temperature and pCO2 treatments. Although elevated pCO2 could result in a reduction in larval supply, future increases in seawater temperatures are even more likely to threaten the future sustainability of the stone-crab fishery.

  11. Identification of entomopathogenic Bacillus isolated from Simulium (Diptera, Simuliidae larvae and adults

    Directory of Open Access Journals (Sweden)

    Cavados CFG

    2001-01-01

    Full Text Available Entomopathogenic bacteria isolated from Simulium larvae and adults from breeding sites in the states of São Paulo and Rio de Janeiro, Brazil, were identified as 18 strains of Bacillus thuringiensis and one of B. sphaericus. Most of these strains were serotyped according to their flagellar antigens. However, nine of the B. thuringiensis samples, could not be serotyped and were designated as "autoagglutinating"; they were also shown to be toxic in preliminary tests against Aedes aegypti larvae. Additionally, B. sphaericus was also shown to be toxic towards Culex quinquefasciatus larvae.

  12. (Herklotsichthys quadrimaculatus) Larvae on Sofala Bank

    African Journals Online (AJOL)

    Abstract—Vertical larval fish movement influences their survival and dispersal, hence recruitment variability. This study presents the vertical behaviour of gold- spot herring (Herklotsichthys quadrimaculatus) larvae observed on the Sofala Bank. (Mozambique) throughout a 48-hour period when depth-stratified samples were.

  13. OCCURRENCE OF PHYTOPHAGOUS SCARABAEIDAE (INSECTA: COLEOPTERA LARVAE IN DIFFERENT SUCCESSION CROP SYSTEMS OCORRÊNCIA DE LARVAS DE SCARABAEIDAE FITÓFAGOS (INSECTA: COLEOPTERA EM DIFERENTES SISTEMAS DE SUCESSÃO DE CULTURAS

    Directory of Open Access Journals (Sweden)

    Elison Floriano Tiago

    2011-01-01

    Full Text Available Information about Scarabaeidae phytophagous are still rare for the Center-West Region of Brazil. Thus, in the experimental area of the Universidade Estadual do Mato Grosso do Sul, in Aquidauana, Mato Grosso do Sul State, Brazil, the succession of soybean, maize, and forage turnip was sowed from February 2004 to October 2005, when the larvae population dynamics was evaluated. From October 2006 to May 2008, nine succession systems were sowed, the larval density evaluated, and the identification of the current species was carried out. When the larvae were sampled for soybean, in January 2005 and 2006, the highest densities were found in the field (3.44 larvae m-2 and 4.19 larvae m-2, respectively. The forage turnip, sampled in October 2004 and 2005, showed the lowest densities (0.03 larvae m-2 and 0.02 larvae m-2, respectively. In the crop succession systems, the following species were found: Liogenys fuscus Blanchard (highest amount, Liogenys bidenticeps Moser, Anomala testaceipennis Blanchard, Paranomala inconstans (Burmeister, Geniates borelli Camerano, Cyclocephala forsteri Endrodi, Cyclocephala verticalis Burmeister, and Phyllophaga sp. For the succession systems with maize sowed at the traditional season, the highest larval densities were found, specially favoring the development of L. fuscus, while the succession systems with soybean, maize, and under fallow, and soybean, crotalaria, and forage turnip, as well as the three systems with cotton-plant, did not favor it.

    KEY-WORDS: Zea mays; Glycine max; Raphanus sativus; soil pests; larvae density.Informações sobre Scarabaeidae fitófagos são ainda escassas para a região Centro-Oeste do Brasil. Por esta razão, na área experimental da Universidade Estadual do Mato Grosso do Sul, em Aquidauana (MS, foi semeada, de fevereiro de 2004 a outubro de 2005, a sucessão de culturas soja, milho e nabo forrageiro, onde se avaliou a dinâmica da densidade larval. De outubro de 2006 a maio

  14. Distribution of Lepidopteran Larvae on Norway Spruce: Effects of Slope and Crown Aspect.

    Science.gov (United States)

    Kulfan, Ján; Dvořáčková, Katarína; Zach, Peter; Parák, Michal; Svitok, Marek

    2016-04-01

    Lepidoptera associated with Norway spruce, Picea abies (L.) Karsten, play important roles in ecosystem processes, acting as plant pests, prey for predators, and hosts for parasites and parasitoids. Their distribution patterns in spruce crowns and forests are only poorly understood. We examined how slope and crown aspect affect the occurrence and abundance of moth larvae on solitary spruce trees in a montane region in Central Europe. Moth larvae were collected from southern and northern crowns of trees growing on south- and north-facing slopes (four treatments) using emergence boxes at the end of winter and by the beating method during the growing season. Species responses to slope and crown aspect were not uniform. Treatment effects on moth larvae were stronger in the winter than during the growing season. In winter, the abundance of bud-boring larvae was significantly higher in northern than in southern crowns regardless of the slope aspect, while both slope and aspect had marginally significant effects on abundance of miners. During the growing season, the occurrence of free-living larvae was similar among treatments. Emergence boxes and beating spruce branches are complementary techniques providing valuable insights into the assemblage structure of moth larvae on Norway spruce. Due to the uneven distribution of larvae detected in this study, we recommend adoption of a protocol that explicitly includes sampling of trees from contrasting slopes and branches from contrasting crown aspect in all seasons. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

    Directory of Open Access Journals (Sweden)

    Zdeňka Svobodová

    Full Text Available Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize, confers resistance to corn rootworms (Diabrotica spp. and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009-2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G and two non-Bt reference hybrids (KIPOUS and PR38N86. Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05. Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017 and non-Bt (DK315 untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability.

  16. Seletividade de inseticidas utilizados em cultura cafeeira para larvas de Cryptolaemus montrouzieri Mulsant Selectivity of insecticides used in the coffee crop to larvae of Cryptolaemus montrouzieri Mulsant

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Dias Rocha

    2011-06-01

    Full Text Available Assim como a maioria dos cultivos, em cafeeiro, a associação de inimigos naturais com produtos fitossanitários seletivos é uma importante estratégia no manejo integrado de pragas (MIP. Dessa forma, este estudo objetivou avaliar a seletividade de agrotóxicos utilizados na cultura cafeeira sobre larvas de Cryptolaemus montrouzieri Mulsant, 1853 (Coleoptera: Coccinellidae, em laboratório. Os bioensaios foram realizados em condições controladas (25±2°C, UR de 70±10% e fotofase de 12 horas. Cada bioensaio consistiu em seis tratamentos e dez repetições, sendo cada parcela composta por duas larvas. Para as comparações das médias dos tratamentos, empregou-se um esquema fatorial inteiramente ao acaso de produtos x número de instares para os diferentes instares subsequentes à aplicação. Os inseticidas utilizados e suas respectivas dosagens de aplicação, em g de i.a. L-1 foram: tiametoxam (0,5, imidacloprido (0,7, óleo mineral (13,3, endossulfam (2,63 e dimetoato (0,48. A testemunha foi composta apenas por água destilada. A aplicação dos produtos foi realizada por meio de torre de Potter. Avaliaram-se a sobrevivência dos espécimes após serem contaminados com os produtos e os efeitos dos compostos sobre os parâmetros reprodutivos do predador. Tiametoxam (0,5, imidacloprido (0,7 e endossulfam (2,63 foram os mais prejudiciais, tendo sido observados, para os dois primeiros, 100% de mortalidade de larvas de primeiro e de segundo instares um dia após a aplicação e significativa redução na sobrevivência das larvas de terceiro e quarto instares. Dimetoato (0,48 foi nocivo para larvas de primeiro instar e levemente nocivo para larvas de quarto instar. Em função da seletividade apresentada pelo óleo mineral (13,3, este pode ser recomendado em compatibilização com o predador C. montrouzieri em programas de MIP na cultura cafeeira, sem prejuízo ao desempenho do inimigo natural.As well as most of the crops, in coffee crop, the

  17. Behavioural responses of Acroneuria lycoria (Ins. Plecopt. ) Larvae to acute and chronic acid exposure

    Energy Technology Data Exchange (ETDEWEB)

    McNichol, R.E.; Scherer, E.

    1987-01-01

    This study was designed to investigate the responses of a perlid stonefly, Acroneuria lycorias (Newman), to acute and chronic acid exposure. Larvae of this species are common in streams and rivers impacted by acidic precipitation. It is also a suggested standard toxicity test species, which in previous studies has proven to be very sensitive to some toxicants. The effects of acute and chronic acid exposure on the locomotor activity, microdistribution, and drift behaviour of the stonefly larvae were studied in laboratory streams. When subjected to a reduction in pH from 8.1 to 2.5 over an 8-h period, larvae showed little behavioural response down to pH 4.2. As the pH fell to 3.0, head-rubbing activity appeared and increased in frequency. At pH 3.0 and below, larvae showed increased gill-ventilatory movements and locomotor activity. Most larvae died within 14 h of exposure to pH 2.5; however, they did not abandon their preferred refuges before death. Larvae exposed to 5 pH levels between 4.5 and 8.2 for 30-50 d displayed no significant changes in locomotor activity, drift behaviour or microdistribution when compared to control animals. Results indicate that later instar larvae of this species are relatively acid tolerant. 29 refs 4 figs 1 tab

  18. Polarized light sensitivity and orientation in coral reef fish post-larvae.

    Directory of Open Access Journals (Sweden)

    Igal Berenshtein

    Full Text Available Recent studies of the larvae of coral-reef fishes reveal that these tiny vertebrates possess remarkable swimming capabilities, as well as the ability to orient to olfactory, auditory, and visual cues. While navigation according to reef-generated chemicals and sounds can significantly affect dispersal, the effect is limited to the vicinity of the reef. Effective long-distance navigation requires at least one other capacity-the ability to maintain a bearing using, for example, a sun compass. Directional information in the sun's position can take the form of polarized-light related cues (i.e., e-vector orientation and percent polarization and/or non-polarized-light related cues (i.e., the direct image of the sun, and the brightness and spectral gradients. We examined the response to both types of cues using commercially-reared post-larvae of the spine-cheeked anemonefish Premnas biaculeatus. Initial optomotor trials indicated that the post-larval stages are sensitive to linearly polarized light. Swimming directionality was then tested using a Drifting In-Situ Chamber (DISC, which allowed us to examine the response of the post-larvae to natural variation in light conditions and to manipulated levels of light polarization. Under natural light conditions, 28 of 29 post-larvae showed significant directional swimming (Rayleigh's test p<0.05, R = 0.74±0.23, but to no particular direction. Swimming directionality was positively affected by sky clarity (absence of clouds and haze, which explained 38% of the observed variation. Moreover, post-larvae swimming under fully polarized light exhibited a distinct behavior of tracking the polarization axis, as it rotated along with the DISC. This behavior was not observed under partially-polarized illumination. We view these findings as an indication for the use of sun-related cues, and polarized light signal in specific, by orienting coral-reef fish larvae.

  19. Polarized light sensitivity and orientation in coral reef fish post-larvae.

    Science.gov (United States)

    Berenshtein, Igal; Kiflawi, Moshe; Shashar, Nadav; Wieler, Uri; Agiv, Haim; Paris, Claire B

    2014-01-01

    Recent studies of the larvae of coral-reef fishes reveal that these tiny vertebrates possess remarkable swimming capabilities, as well as the ability to orient to olfactory, auditory, and visual cues. While navigation according to reef-generated chemicals and sounds can significantly affect dispersal, the effect is limited to the vicinity of the reef. Effective long-distance navigation requires at least one other capacity-the ability to maintain a bearing using, for example, a sun compass. Directional information in the sun's position can take the form of polarized-light related cues (i.e., e-vector orientation and percent polarization) and/or non-polarized-light related cues (i.e., the direct image of the sun, and the brightness and spectral gradients). We examined the response to both types of cues using commercially-reared post-larvae of the spine-cheeked anemonefish Premnas biaculeatus. Initial optomotor trials indicated that the post-larval stages are sensitive to linearly polarized light. Swimming directionality was then tested using a Drifting In-Situ Chamber (DISC), which allowed us to examine the response of the post-larvae to natural variation in light conditions and to manipulated levels of light polarization. Under natural light conditions, 28 of 29 post-larvae showed significant directional swimming (Rayleigh's test p<0.05, R = 0.74±0.23), but to no particular direction. Swimming directionality was positively affected by sky clarity (absence of clouds and haze), which explained 38% of the observed variation. Moreover, post-larvae swimming under fully polarized light exhibited a distinct behavior of tracking the polarization axis, as it rotated along with the DISC. This behavior was not observed under partially-polarized illumination. We view these findings as an indication for the use of sun-related cues, and polarized light signal in specific, by orienting coral-reef fish larvae.

  20. An appraisal of certain larval behavioural activities as affected by gamma irradiation of Spodoptera larvae

    International Nuclear Information System (INIS)

    Seth, R.K.; Sehgal, S.S.

    1987-01-01

    Gamma irradiation of Spodoptera litura larvae induced an abatement in their locomotor activity. The food perception range and feeding behaviour of the larvae were also impaired. Of various dosages tested, 4 Krad (the sterilizing dose for larvae) caused a decline in locomotor speed. The first instar larvae, for instance showed decline in a speed of 3.74 cm/min to 2.96 cm/min. Similarly at this dose, the third instar larvae exhibited a reduction in speed to the extent of 38 to 45 per cent, the normal speed being 8.02 cm/min. The reactive distances of the first and third instar normal larvae were 5.30 cm and 7.36, respectively. This reactive distance was reduced by about 25 per cent after irradiation at 4 Krad, thus decreasing the food perception capacity significantly. The feeding behaviour too was significantly affected whereas the dose range less than 4 Krad did not induce such a marked impact. (author). 9 refs., 2 tables

  1. Elemental concentrations of aquatic insect larvae and attached algae on tone surfaces in an uncontaminated stream

    International Nuclear Information System (INIS)

    Momoshima, N.; Sugihara, S.; Hibino, K.; Nakamura, Y.

    2009-01-01

    Elemental concentrations of aquatic insect larvae and attached algae in an uncontaminated river were analyzed by instrumental neutron activation analysis (INAA) via the k 0 -standardization method. The aquatic insect larvae found were all intolerant species. No significant difference was observed int he elemental concentrations of aquatic insect larvae and attached algae long the river. Similar elemental concentrations were observed in the aquatic insect larvae collected at a fixed sampling point for two years. An analysis by the ratio-matching technique indicated a higher generic relationship between aquatic insect larvae and attached algae than river water. (author)

  2. Cockchafer larvae smell host root scents in soil.

    Directory of Open Access Journals (Sweden)

    Sonja Weissteiner

    Full Text Available In many insect species olfaction is a key sensory modality. However, examination of the chemical ecology of insects has focussed up to now on insects living above ground. Evidence for behavioral responses to chemical cues in the soil other than CO(2 is scarce and the role played by olfaction in the process of finding host roots below ground is not yet understood. The question of whether soil-dwelling beetle larvae can smell their host plant roots has been under debate, but proof is as yet lacking that olfactory perception of volatile compounds released by damaged host plants, as is known for insects living above ground, occurs. Here we show that soil-dwelling larvae of Melolontha hippocastani are well equipped for olfactory perception and respond electrophysiologically and behaviorally to volatiles released by damaged host-plant roots. An olfactory apparatus consisting of pore plates at the antennae and about 70 glomeruli as primary olfactory processing units indicates a highly developed olfactory system. Damage induced host plant volatiles released by oak roots such as eucalyptol and anisol are detected by larval antennae down to 5 ppbv in soil air and elicit directed movement of the larvae in natural soil towards the odor source. Our results demonstrate that plant-root volatiles are likely to be perceived by the larval olfactory system and to guide soil-dwelling white grubs through the dark below ground to their host plants. Thus, to find below-ground host plants cockchafer larvae employ mechanisms that are similar to those employed by the adult beetles flying above ground, despite strikingly different physicochemical conditions in the soil.

  3. Programa de computador para reconhecimento da larva de Aedes aegypti e Aedes albopictus

    OpenAIRE

    São Thiago, André Iwersen de; Kupek, Emil; Ferreira Neto, Joaquim Alves; São Thiago, Paulo de Tarso

    2002-01-01

    Software for pattern recognition of the larvae of mosquitoes Aedes aegypti and Aedes albopictus, biological vectors of dengue and yellow fever, has been developed. Rapid field identification of larva using a digital camera linked to a laptop computer equipped with this software may greatly help prevention campaigns.Foi desenvolvido um programa de computador para reconhecimento da larva de Aedes aegypti e Aedes albopictus, vetores biológicos de dengue e febre amarela. O programa possibilita rá...

  4. 60Co accumulation from sediment and planktonic algae by midge larvae (Chironomus luridus)

    International Nuclear Information System (INIS)

    Baudin, J.P.; Nucho, R.

    1992-01-01

    This paper reports the results of several experiments carried out to evaluate uptake and retention by a limicolous midge larva of 60 Co retained in sediment, either adsorbed on mineral particles or bound to planktonic algae. In order to determine their relative contributions in radionuclide accumulation, the different vectors (water, algae and sediment) were first labelled individually and then simultaneously. 60 Co accumulation from water and from algae results in a maximum concentration factor of 30 and in a mean trophic transfer factor of 4·5 × 10 −3 . The level of contamination of midge larvae from sediment is markedly influenced by the presence of endogenous organic matter. Thus the radionuclide transfer factor is about twice as high for larvae placed in labelled raw sediment than for larvae placed in labelled incinerated sediment, in the presence as in the absence of contaminated planktonic algae. Irrespective of the contamination conditions, 60 Co depuration from midge larvae is a very rapid phenomenon that corresponds, in all cases, to a radionuclide half-life of only a few days

  5. 60Co accumulation from sediment and planktonic algae by midge larvae (Chironomus luridus)

    International Nuclear Information System (INIS)

    Baudin, J.P.; Nucho, R.

    1992-01-01

    This paper reports the results of several experiments carried out to evaluate uptake and retention by a limicolous midge larva of 60 Co retained in sediment, either adsorbed on mineral particles or bound to planktonic algae. In order to determine their relative contributions in radionuclide accumulation, the different vectors (water, algae and sediment) were first labelled individually and then simultaneously. 60 Co accumulation from water and from algae results in a maximum concentration factor of 30 and in a mean trophic transfer factor of 4.5 x 10 -3 . The level of contamination of midge larvae from sediment is markedly influenced by the presence of endogenous organic matter. Thus the radionuclide transfer factor is about twice as high for larvae placed in labelled raw sediment than for larvae placed in labelled incinerated sediment, in the presence as in the absence of contaminated planktonic algae. Irrespective of the contamination conditions, 60 Co depuration from midge larvae is a very rapid phenomenon that corresponds, in all cases, to a radionuclide half-life of only a few days. (author)

  6. Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.

    Science.gov (United States)

    Li, Yingying; Dou, Kai; Gao, Shigang; Sun, Jianan; Wang, Meng; Fu, Kehe; Yu, Chuanjin; Wu, Qiong; Li, Yaqian; Chen, Jie

    2015-08-03

    Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. First record of larvae of the water mite Hydrachna processifera Piersig, 1895 from Turkey (Acari, Hydrachnidia, Hydrachnidae

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    Medeni Aykut

    2018-02-01

    Full Text Available Larvae of water mite Hydrachna processifera Piersig, 1895 (Acari, Hydrachnidiae were reported on diving beetles Dytiscus marginalis Linnaeus, 1758 (Coleoptera, Dytiscidae from Turkey. The redescription of the larva was made. Earlier, the larva H. processifera was described as H. inermis, but it was subsequently synonymized with H. processifera. The larva of H. processifera is a new record for the Turkish fauna. All larvae of H. processifera were found on the mesosternum of the one specimens (prevalence = 16.7%.

  8. Reef odor: a wake up call for navigation in reef fish larvae.

    Directory of Open Access Journals (Sweden)

    Claire B Paris

    Full Text Available The behavior of reef fish larvae, equipped with a complex toolbox of sensory apparatus, has become a central issue in understanding their transport in the ocean. In this study pelagic reef fish larvae were monitored using an unmanned open-ocean tracking device, the drifting in-situ chamber (DISC, deployed sequentially in oceanic waters and in reef-born odor plumes propagating offshore with the ebb flow. A total of 83 larvae of two taxonomic groups of the families Pomacentridae and Apogonidae were observed in the two water masses around One Tree Island, southern Great Barrier Reef. The study provides the first in-situ evidence that pelagic reef fish larvae discriminate reef odor and respond by changing their swimming speed and direction. It concludes that reef fish larvae smell the presence of coral reefs from several kilometers offshore and this odor is a primary component of their navigational system and activates other directional sensory cues. The two families expressed differences in their response that could be adapted to maintain a position close to the reef. In particular, damselfish larvae embedded in the odor plume detected the location of the reef crest and swam westward and parallel to shore on both sides of the island. This study underlines the critical importance of in situ Lagrangian observations to provide unique information on larval fish behavioral decisions. From an ecological perspective the central role of olfactory signals in marine population connectivity raises concerns about the effects of pollution and acidification of oceans, which can alter chemical cues and olfactory responses.

  9. Metamorfosis del aparato digestivo de larvas carnívoras de Ceratophrys cranwelli (Anura: Leptodactylidae

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    Ulloa Kreisel, Zandra E.

    2000-12-01

    Full Text Available Las larvas carnívoras de Ceratophrys cranwelli presentan un tubo digestivo más corto que la mayoría de las larvas de anuros, tiene 6 veces la longitud del cuerpo del renacuajo y se caracteriza también por tener un estómago larval. El presente trabajo tiene como objetivo el determinar el grado de transformaciones en la cavidad bucofaríngea y tubo digestivo en larvas de esta especie durante la metamorfosis y comparar las estructuras digestivas estudiadas en otras especies de Leptodactylidae de la subfamilia Ceratophryinae y especies con otros hábitos alimenticios. Carnivorous larvae from Ceratophrys cranwelli present a digestive tube shorter than most of the anuran larvae, have 6 times a tadpole’s body length and they are also characterized by the presence of a larval stomach. The aim of this work is determine the grade of transformations in the buccopharyngeal cavity and digestive tube during the metamorphosis in larvae of this species and compare the digestive structures studied in other species of Leptodactylidae of the subfamily Ceratophryinae and another species with different diets.

  10. Fine structure of selected mouthpart sensory organs of gypsy moth larvae

    Science.gov (United States)

    Vonnie D.C. Shields

    2011-01-01

    Gypsy moth larvae, Lymantria dispar (L.), are major pest defoliators in most of the United States and destroy millions of acres of trees annually. They are highly polyphagous and display a wide host plant preference, feeding on the foliage of hundreds of plants, such as oak, maple, and sweet gum. Lepidopteran larvae, such as the gypsy moth, depend...

  11. Symbiotic Bacteria Enable Olive Fly Larvae to Overcome Host Defenses

    International Nuclear Information System (INIS)

    Ben-Yosef, Michael; Yuval, Boaz; Pasternak, Zohar; Jurkevitch, Edouard

    2016-01-01

    Ripe fruit offer readily available nutrients for many animals, including fruit fly larvae (Diptera: Tephritidae) and their associated rot-inducing bacteria. Yet, during most of their ontogeny, fruit remain chemically defended and effectively suppress herbivores and pathogens by high levels of secondary metabolites. Olive flies (Bactrocera oleae) are uniquely able to develop in unripe olives. Unlike other frugivorous tephritids, the larvae maintain bacteria confined within their midgut caeca. We examined the interaction between larvae, their associated bacteria, and fruit chemical defence, hypothesizing that bacterial contribution to larval development is contingent on the phenology of fruit defensive chemistry. We demonstrate that larvae require their natural complement of bacteria (Candidatus Erwinia dacicola: Enterobacteriaceae) in order to develop in unripe olives. Conversely, when feeding on ripe fruit, larval development proceeds independently of these bacteria. Our experiments suggest that bacteria counteract the inhibitory effect of oleuropein—the principal phenolic glycoside in unripe olives. In light of these results, we suggest that the unique symbiosis in olive flies, compared with other frugivorous tephritids, is understood by considering the relationship between the fly, bacteria and fruit chemistry. When applied in an evolutionary context, this approach may also point out the forces which shaped symbioses across the Tephritidae. (author)

  12. Density, Viability Conidia And Symptoms of Metarhizium anisopliae infection on Oryctes rhinoceros larvae

    Science.gov (United States)

    Indriyanti, D. R.; Putri, R. I. P.; Widiyaningrum, P.; Herlina, L.

    2017-04-01

    M. anisopliae is parasitic fungus on insect pests; it is used as a biocontrol agent. M. anisopliae can be propagated on maize or rice substrate. M. anisopliae is currently sold in the form of kaolin powder formulations. Before it is used to check the density, viability and pathogenicity of M. anisopliae. However the problem is the kaolin powder very soft, so it difficult to distinguish between kaolin and conidia. This article gives information on how to calculate conidia density, viability and symptoms of M. anisopliae infection on Oryctes rhinoceros larvae. The study was conducted in the laboratory to determine the density and viability. The pathogenicity testing was done using pots. The Pot is containing soil substrate mixed with M. Anispoliae and ten tails O. Rhinoceros larvae per pot. The results showed that the density of M. anisopliae conidia was 1.81 x 108 conidia mL-1 and the viability was 94% within 24 hours. The larval mortality began to emerge in the 1st week, and all larvae died at the sixth week. The symptom of M. anisopliae infection on Oryctes rhinoceros larvae, there was a black spot on the larval integument. The larvae movements become slow and poor appetite; it will die within 3-7 days. The larvae die hard, and the white hyphae grow on the body surface that turns green.

  13. Residual Effect of Pesticides used in Integrated Apple Production on Chrysoperlaexterna (Hagen (Neuroptera: Chrysopidae Larvae Efecto Residual de los Pesticidas utilizados en la Producción integrada de Manzanas en las Larvas de Chrysoperla externa (Hagen (Neuroptera: Chrysopidae

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    Alexandre P Moura

    2012-06-01

    Full Text Available Temperate fruit crops are an important economic activity for growers in southern Brazil. However, several pest species are associated to apple (Malus domestica Borkh. crops in Brazil. Pesticides are largely used to control them and one way to change this is to combine selective pesticides and predator insects. The goal of this research was to evaluate the effects of the abamectin, carbaryl, fenitrothion, methidathion, sulfur, and trichlorfon pesticides on the survival and stage length of larvae and pupae, adult oviposition from treated larvae, and hatched eggs of two Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae populations. The compounds were sprayed on glass plates in accordance with the International Organization for Biological Control (IOBC recommendations. First- and second-instar larvae were exposed to pesticide residues. Carbaryl, fenitrothion, and methidathion caused 100% mortality of first- and second-instar larvae. Changes in the number of eggs laid by females from first- and second-instar larvae exposed to residues of abamectin and sulfur, or abamectin, sulfur, and trichlorfon, respectively, were not observed. Only abamectin reduced the number of hatched eggs laid by females in Bento Gonçalves from treated first-instar larvae. Sulfur reduced the viability of C. externa eggs in Bento Gonçalves and Vacaria females from treated second-instar larvae, whereas trichlorfon and abamectin reduced the viability of eggs in Vacaria females. In conclusion, carbaryl, fenitrothion and methidathion were harmful to C. externa. Trichlorfon was harmful to first-instar larvae and slightly harmful to second-instar larvae. Abamectin and sulfur were slightly harmful to first-instar larvae and harmless to second-instar larvae.El cultivo de frutas de clima templado es una actividad económica importante para agricultores del Sur de Brasil. Sin embargo, varias especies de plagas están asociadas al cultivo de la manzana (Malus domestica Borkh. en

  14. Biological control of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps

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    Willian Marinho Dourado Coelho

    2017-08-01

    Full Text Available Mosquitoes can act as vectors of important diseases such as malaria, dengue, Zika virus, yellow fever, Chikungunya and Mayaro fever, in addition to filariasis. The use of insecticides, larvicides, bed nets and repellents, besides the use of drugs as chemoprevention and the treatment of the sick are currently the pillars of the control of these vectors. We studied the biological control against of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps of the species M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii. Larvae of mosquitoes were collected from the breeding environment and placed in a 500 and 1000 l tank containing 60 shrimps/m2. The predatory activity was evaluated for 30 days and, in all groups it was observed that 100% of the larvae were consumed in few minutes. In the environment, these same species of crustaceans were released in water bodies with the presence of larvae of these insects. In just 72 h there was a marked reduction of the larvae in the release sites of shrimps. Similarly, there was a reduction in the number of adult mosquitoes caught near the breeding sites, allowing to infer that, in places where the crustaceans were released, the predatory activity on the larvae of mosquitoes was sufficient to reduce the number of adult mosquitoes p ≤ 0,05. This is the first description of the predatory activity of M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii on An. darlingi, A. aegypti and C. quinquefasciatus larvae, constituting an important tool of biological control of these parasites-vectors.

  15. Influence of irradiation on development of Caribbean fruit fly (diptera: tephritidae) larvae

    International Nuclear Information System (INIS)

    Nation, J.L.; Milne, K.; Dykstra, T.M.

    1995-01-01

    Larvae of the Caribbean fruit fly, Anastrepha suspensa (Loew), were irradiated at hatching with 0, 5, 10, 20, 50, 75, 100 and 150 Gy doses from a Cesium-137 source and dissected for measurements of the supraesophageal ganglion (brain) and proventriculus (B/Prv) as mature third instars. Cross-sectional area of a plane through the brain and proventriculus, and simple dorsal width measurements of the two organs were evaluated as indicators of radiation exposure. Brain area, brain width, and brain/proventriculus (B/Prv) ratios were significantly different from controls in insects treated with a dose ≥20 Gy. Detailed dissections of hatching larvae exposed to 50 Gy revealed reductions in brain growth, small and misshapen compound eye and leg imaginal disks, and a ventral nerve cord that was elongated and sinuous. Larvae irradiated on the 1st d of each of the three instars had smaller brains, with the percentage of reduction in brain size being greater the younger the larvae were at the time of exposure. Brain and proventriculus measurements and calculated B/Prv values are indicative of irradiation in Caribbean fruit fly larvae, but the procedure may not be adaptable for routine use by quarantine inspectors. 14 refs., 4 figs., 2 tabs

  16. Monograph On Bothid Larvae (Pleuronectiformes - Pisces)

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    in the preparation of a descriptive document on the larvae of flat fishes from the Indian Ocean. However, study of the larval forms from the Indian Ocean has been made possible due to the availability of material from the Naga Expedition (1959-61) from the Gulf...

  17. Highly polygenic variation in environmental perception determines dauer larvae formation in growing populations of Caenorhabditis elegans.

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    James W M Green

    Full Text Available Determining how complex traits are genetically controlled is a requirement if we are to predict how they evolve and how they might respond to selection. This requires understanding how distinct, and often more simple, life history traits interact and change in response to environmental conditions. In order to begin addressing such issues, we have been analyzing the formation of the developmentally arrested dauer larvae of Caenorhabditis elegans under different conditions.We find that 18 of 22 previously identified quantitative trait loci (QTLs affecting dauer larvae formation in growing populations, assayed by determining the number of dauer larvae present at food patch exhaustion, can be recovered under various environmental conditions. We also show that food patch size affects both the ability to detect QTLs and estimates of effect size, and demonstrate that an allele of nath-10 affects dauer larvae formation in growing populations. To investigate the component traits that affect dauer larvae formation in growing populations we map, using the same introgression lines, QTLs that affect dauer larvae formation in response to defined amounts of pheromone. This identifies 36 QTLs, again demonstrating the highly polygenic nature of the genetic variation underlying dauer larvae formation.These data indicate that QTLs affecting the number of dauer larvae at food exhaustion in growing populations of C. elegans are highly reproducible, and that nearly all can be explained by variation affecting dauer larvae formation in response to defined amounts of pheromone. This suggests that most variation in dauer larvae formation in growing populations is a consequence of variation in the perception of the food and pheromone environment (i.e. chemosensory variation and in the integration of these cues.

  18. The hatching larva of the priapulid worm Halicryptus spinulosus.

    Science.gov (United States)

    Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

    2009-05-26

    Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

  19. Cutaneous larva migrans after a trip to the Caribean

    OpenAIRE

    García-Fernández, Lisset; Calderón, María

    2014-01-01

    La larva migrans cutánea es una parasitosis ocasionada por las larvas de Ancylostoma braziliense y Ancylostoma caninum, cuyo vehículo es la arena de playas infestadas. Los perros y gatos son los hospederos definitivos. Esta parasitosis es endémica en las costas del Caribe, África, Australia y Asia. Presentamos el caso clínico de una mujer de 27 años de edad, quien tras haber realizado un viaje al Caribe mexicano y haber estado en contacto con arena de playa, presentó unas lesiones en el pie d...

  20. Development of digestive enzymes in larvae of Mayancichlid Cichlasoma urophthalmus

    OpenAIRE

    López Ramírez, G.; Cuenca Soria, C.A.; Álvarez González, C.A.; Tovar Ramírez, D.; Ortiz Galindo, José Luis; Perales García, N.; Márquez Couturier, G.; Arias Rodríguez, L.; Indy, J.R.; Contreras Sánchez, W.M.; Gisbert, E.; Moyano, F.J.

    2011-01-01

    The development of digestive enzymes during the early ontogeny of the Mayan cichlid (Cichlasoma urophthalmus) was studied using biochemical and electrophoretic techniques. From yolk absorption (6 days after hatching: dah), larvae were fed Artemia nauplii until 15 dah, afterward they were fed with commercial microparticulated trout food (45% protein and 16% lipids) from 16 to 60 dah. Several samples were collected including yolk-sac larvae (considered as day 1 after hatching) and specimens up ...

  1. Luminous vibriosis in rock lobster Jasus verreauxi (Decapoda: Palinuridae) phyllosoma larvae associated with infection by Vibrio harveyi.

    Science.gov (United States)

    Diggles, B K; Moss, G A; Carson, J; Anderson, C D

    2000-11-14

    Studies were conducted to determine the cause of outbreaks of luminous vibriosis in phyllosoma larvae of the packhorse rock lobster Jasus verreauxi reared in an experimental culture facility. On 2 separate occasions mortalities of up to 75% over a period of 4 wk were observed in 4th to 5th and 8th to 10th instar phyllosomas at water temperatures of 20 and 23 degrees C, respectively. Affected larvae became opaque, exhibited small red spots throughout the body and pereiopods, and were faintly luminous when viewed in the dark. Histopathology showed that the gut and hepatopancreas tubules of moribund phyllosomas contained massive bacterial plaques. The hepatopancreas tubules of moribund larvae were atrophic and some contained necrotic cells sloughed into the lumen. Dense, pure cultures of a bacterium identified as Vibrio harveyi were isolated from moribund larvae. The disease syndrome was reproduced by in vivo challenge and V. harveyi was successfully reisolated from diseased larvae after apparently healthy larvae were exposed by immersion to baths of more than 10(4) V. harveyi ml(-1) at 24 degrees C. Injured larvae were more susceptible to infection than were healthy larvae. Survival of larvae experimentally and naturally exposed to V. harveyi was improved when antibiotics were administered via bath exposures.

  2. Morfologia do trato digestório e dieta de larvas de Bryconamericus aff. iheringii (Boulenger, 1887 (Osteichthyes, Characidae = Morphology of Digestive tract and diet of Bryconamericus aff. iheringii larvae (Boulenger, 1887 (Osteichthyes, Characidae

    Directory of Open Access Journals (Sweden)

    Renato Ziliani Borges

    2006-01-01

    Full Text Available Este trabalho teve como objetivo analisar alguns aspectos da alimentação de larvas de Bryconamericus aff. iheringii, capturadas nos meses de julho e novembro de 2001, nas regiões limnética e litorânea do reservatório de Santa Maria, rio Piquiri, Estado do Paraná. As larvas apresentaram boca subterminal durante todo o seu desenvolvimento. O tubo digestório se diferenciou em estômago e intestino apenas no estágio de pós-flexão. As larvas consumiram, principalmente, algas e microcrustáceos, o que permitiu caracterizá-las como planctófagas. A intensa modificação morfológica no trato digestório nos indivíduos em pósflexão coincidiu com o aumento na abundância de algas em relação aos itens de origemanimal; porém, de forma geral, a ocorrência aumentou para todos os itens. A análise do grau de digestão dos itens alimentares sugeriu que indivíduos em pré-flexão alimentaram-se, possivelmente, durante o dia, e os mais desenvolvidos, durante o entardecer e no períodonoturno.The aim of this study was to analyze some feeding treats of Bryconamericus aff. iheringii larvae, sampled in both the limnetic and littoral regions of the Piquiri River, in Santa Maria reservoir, between July and November 2001. The larvae presented sub-terminal mouth in larval period. The digestive tract differentiated in terms of stomach and intestine only in the postflexion larvae. The larvae fed mainly on algae and microcrustacea allowing to characterize them as planktivorous. The intense morphologic shift in the digestive tract in the postflexion larvae coincided with an increase in the abundance of algae in relation to animals items; however, in general, all the items had their occurrence increased. Analysis of the digestion stage suggested that preflexion larvae, possibly, fed themselves during the day, and those more developed, at dusk and night.

  3. Occurrence of viral pathogens in Penaeus monodon post-larvae from aquaculture hatcheries

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    Toms C. Joseph

    2015-09-01

    Full Text Available Viral pathogens appear to exert the most significant constraints on the growth and survival of crustaceans under culture conditions. The prevalence of viral pathogens White Spot Syndrome Virus (WSSV, Hepatopancreatic Parvo Virus (HPV, Monodon Baculo Virus (MBV and Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV in Penaeus monodon post-larvae was studied. Samples collected from different hatcheries and also samples submitted by farmers from Kerala were analyzed. Out of 104 samples collected, WSSV was detected in 12.5% of the post-larvae samples. Prevalence of concurrent infections by HPV, MBV and WSSV (either dual or triple infection was present in 60.6% of the total post-larvae tested. Out of the 51 double positives, 98% showed either HPV or IHHNV infection. HPV or IHHNV was detected in 11 post-larval samples showing triple viral infection. This is the first report of IHHNV from India. Result of this study reveals the lack of efficient screening strategies to eradicate viruses in hatchery reared post-larvae.

  4. Diphyllobothrium latum in Italy: plerocercoids larvae distribution in perch (Perca fluviatilis fillets

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    MariaLetizia Fioravanti

    2013-04-01

    Full Text Available Following the diffusion of new eating habits (consumption of uncooked, undercooked, marinated or cold-smoked fish, some cases of parasitic zoonosis from freshwater fish are recently reappeared in Italy. One of these is tapeworm Diphyllobothrium latum, whose final host could be human. This study aimed to individuate the position of plerocercoid larvae inside perch fillets (Perca fluviatilis caught in 4 different sites on Como lake in 2011. The fish analyzed were 390. The larvae totally isolated from 112 positive fishes were 164: 85 found in the right fillets and 79 in left ones. According to dorso-ventral disposition in fish, 144 larvae were individuated in dorsal muscles and 20 in ventral ones. Data collected confirm that plerocercoid larvae prefer the upper mass of perch muscle. Dietary education and sanitary care on fish supply are necessary to prevent the diffusion of tapeworm zoonosis in high-risk zones. European legislation establishes freezing to sanitize fish to be eaten raw, marinated or cold-smoked.

  5. Proteome response of Tribolium castaneum larvae to Bacillus thuringiensis toxin producing strains.

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    Estefanía Contreras

    Full Text Available Susceptibility of Tribolium castaneum (Tc larvae was determined against spore-crystal mixtures of five coleopteran specific and one lepidopteran specific Bacillus thuringiensis Cry toxin producing strains and those containing the structurally unrelated Cry3Ba and Cry23Aa/Cry37Aa proteins were found toxic (LC(50 values 13.53 and 6.30 µg spore-crystal mixture/µL flour disc, respectively. Using iTRAQ combined with LC-MS/MS allowed the discovery of seven novel differentially expressed proteins in early response of Tc larvae to the two active spore-crystal mixtures. Proteins showing a statistically significant change in treated larvae compared to non-intoxicated larvae fell into two major categories; up-regulated proteins were involved in host defense (odorant binding protein C12, apolipophorin-III and chemosensory protein 18 and down-regulated proteins were linked to metabolic pathways affecting larval metabolism and development (pyruvate dehydrogenase Eα subunit, cuticular protein, ribosomal protein L13a and apolipoprotein LI-II. Among increased proteins, Odorant binding protein C12 showed the highest change, 4-fold increase in both toxin treatments. The protein displayed amino acid sequence and structural homology to Tenebrio molitor 12 kDa hemolymph protein b precursor, a non-olfactory odorant binding protein. Analysis of mRNA expression and mortality assays in Odorant binding protein C12 silenced larvae were consistent with a general immune defense function of non-olfactory odorant binding proteins. Regarding down-regulated proteins, at the transcriptional level, pyruvate dehydrogenase and cuticular genes were decreased in Tc larvae exposed to the Cry3Ba producing strain compared to the Cry23Aa/Cry37Aa producing strain, which may contribute to the developmental arrest that we observed with larvae fed the Cry3Ba producing strain. Results demonstrated a distinct host transcriptional regulation depending upon the Cry toxin treatment. Knowledge

  6. Maggot Instructor: Semi-Automated Analysis of Learning and Memory in Drosophila Larvae

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    Urte Tomasiunaite

    2018-06-01

    Full Text Available For several decades, Drosophila has been widely used as a suitable model organism to study the fundamental processes of associative olfactory learning and memory. More recently, this condition also became true for the Drosophila larva, which has become a focus for learning and memory studies based on a number of technical advances in the field of anatomical, molecular, and neuronal analyses. The ongoing efforts should be mentioned to reconstruct the complete connectome of the larval brain featuring a total of about 10,000 neurons and the development of neurogenic tools that allow individual manipulation of each neuron. By contrast, standardized behavioral assays that are commonly used to analyze learning and memory in Drosophila larvae exhibit no such technical development. Most commonly, a simple assay with Petri dishes and odor containers is used; in this method, the animals must be manually transferred in several steps. The behavioral approach is therefore labor-intensive and limits the capacity to conduct large-scale genetic screenings in small laboratories. To circumvent these limitations, we introduce a training device called the Maggot Instructor. This device allows automatic training up to 10 groups of larvae in parallel. To achieve such goal, we used fully automated, computer-controlled optogenetic activation of single olfactory neurons in combination with the application of electric shocks. We showed that Drosophila larvae trained with the Maggot Instructor establish an odor-specific memory, which is independent of handling and non-associative effects. The Maggot Instructor will allow to investigate the large collections of genetically modified larvae in a short period and with minimal human resources. Therefore, the Maggot Instructor should be able to help extensive behavioral experiments in Drosophila larvae to keep up with the current technical advancements. In the longer term, this condition will lead to a better understanding of

  7. Responses of the metabolism of the larvae of Pocillopora damicornis to ocean acidification and warming.

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    Emily B Rivest

    Full Text Available Ocean acidification and warming are expected to threaten the persistence of tropical coral reef ecosystems. As coral reefs face multiple stressors, the distribution and abundance of corals will depend on the successful dispersal and settlement of coral larvae under changing environmental conditions. To explore this scenario, we used metabolic rate, at holobiont and molecular levels, as an index for assessing the physiological plasticity of Pocillopora damicornis larvae from this site to conditions of ocean acidity and warming. Larvae were incubated for 6 hours in seawater containing combinations of CO2 concentration (450 and 950 µatm and temperature (28 and 30°C. Rates of larval oxygen consumption were higher at elevated temperatures. In contrast, high CO2 levels elicited depressed metabolic rates, especially for larvae released later in the spawning period. Rates of citrate synthase, a rate-limiting enzyme in aerobic metabolism, suggested a biochemical limit for increasing oxidative capacity in coral larvae in a warming, acidifying ocean. Biological responses were also compared between larvae released from adult colonies on the same day (cohorts. The metabolic physiology of Pocillopora damicornis larvae varied significantly by day of release. Additionally, we used environmental data collected on a reef in Moorea, French Polynesia to provide information about what adult corals and larvae may currently experience in the field. An autonomous pH sensor provided a continuous time series of pH on the natal fringing reef. In February/March, 2011, pH values averaged 8.075 ± 0.023. Our results suggest that without adaptation or acclimatization, only a portion of naïve Pocillopora damicornis larvae may have suitable metabolic phenotypes for maintaining function and fitness in an end-of-the century ocean.

  8. Natural variation in gene expression in the early development of dauer larvae of Caenorhabditis elegans

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    Barker Gary LA

    2009-07-01

    Full Text Available Abstract Background The free-living nematode Caenorhabditis elegans makes a developmental decision based on environmental conditions: larvae either arrest as dauer larva, or continue development into reproductive adults. There is natural variation among C. elegans lines in the sensitivity of this decision to environmental conditions; that is, there is variation in the phenotypic plasticity of dauer larva development. We hypothesised that these differences may be transcriptionally controlled in early stage larvae. We investigated this by microarray analysis of different C. elegans lines under different environmental conditions, specifically the presence and absence of dauer larva-inducing pheromone. Results There were substantial transcriptional differences between four C. elegans lines under the same environmental conditions. The expression of approximately 2,000 genes differed between genetically different lines, with each line showing a largely line-specific transcriptional profile. The expression of genes that are markers of larval moulting suggested that the lines may be developing at different rates. The expression of a total of 89 genes was putatively affected by dauer larva or non-dauer larva-inducing conditions. Among the upstream regions of these genes there was an over-representation of DAF-16-binding motifs. Conclusion Under the same environmental conditions genetically different lines of C. elegans had substantial transcriptional differences. This variation may be due to differences in the developmental rates of the lines. Different environmental conditions had a rather smaller effect on transcription. The preponderance of DAF-16-binding motifs upstream of these genes was consistent with these genes playing a key role in the decision between development into dauer or into non-dauer larvae. There was little overlap between the genes whose expression was affected by environmental conditions and previously identified loci involved in

  9. Color variability and body size of larvae of two Epomis species (Coleoptera: Carabidae in Israel

    Directory of Open Access Journals (Sweden)

    Gil Wizen

    2011-07-01

    Full Text Available Species identification using the characteristics of developmental stages is challenging. However, for insect taxonomy the coloration of larval stages can be an informative feature. The use of live specimens is recommended for this because the color fades in preserved specimens. In this study we examine the possibility of using variation in coloration and color pattern of larvae in order to distinguish between two ground beetles species Epomis dejeani Dejean, 1831 and E. circumscriptus Duftschmid, 1812. We present an atlas and describe the coloration and body size of the three larval stages of the above species based on live specimens. The first instar larvae of the two Epomis species can be easily distinguished based on their color. From the second instar on, the variability in coloration and color patterns increases, creating an overlap in these attributes between larvae of the two species. Except for minor differences in color of the antennae and the base of the mandibles, larvae of the two species are indistinguishable at the second and third larval stages. To the best of our knowledge this is the first attempt to use variation in coloration and color pattern in live larvae in order to identify coleopterans. The color atlas of the larvae enables simple separation of the two Epomis species without requiring sophisticated magnifying devices, although it is less straightforward at the second and third larval stages. We found similar body lengths between the two species for all developmental stages, except for third instar larvae prior to pupation. In the two species the difference in larval body length before pupation positively correlated with that of the adult beetles. More than 70% of the adults' length can be explained by the length of the late third-instar larva; i.e. the large larvae develop into large adults. The larger specimens are the females.

  10. Performances of local poultry breed fed black soldier fly larvae reared on horse manure

    Directory of Open Access Journals (Sweden)

    Nassim Moula

    2018-03-01

    Full Text Available In poultry, feed based on maggots, like larvae of black soldier fly (Hermetia illucens is an attractive option to substitute current ingredients which are expensive and often in direct or indirect competition with human food. Little information is currently available on the utility of these larvae in poultry feed, so goals of this study were to determine whether larvae could be reared on horse manure under traditional farming conditions and to evaluate the growth performances of a local poultry fed these larvae and the fatty acids profiles of their meat. After freezing and thawing, larvae were introduced in the feed of Ardennaise chickens between 30 and 80 days of age. Birds in the control group received a commercial standard feed, while those in the treatment group received the same commercial feed in which 8% was substituted with whole fresh larvae corresponding to 2% on a dry matter basis. Means ± standard errors of larval length and weight were 20.67 ± 2.21 mm and 0.14 ± 0.02 g, respectively. Mean larval percentages of dry matter and of substances extractable in diethyl ether were 24.6% and 23.1%, respectively. Larval fatty acids profiles were predominantly composed of lauric acid (28.1% and palmitic acid (22.0%. Least squares means of weekly weights of chicken, adjusted for the effects of sex, replication and initial weights, were significantly higher (P < 0.05 by 77.03 ± 53.37 g in larvae-fed than in control chickens. All other measurements were not statistically different between larvae-fed and control chicken, including fatty acid profiles, protein content and ω6/ω3 ratio. Keywords: Insect farming, Chicken, Local breed, Growth performance, Meat quality, Fatty acid profile

  11. Comparison of two techniques used for the recovery of third-stage strongylid nematode larvae from herbage.

    Science.gov (United States)

    Krecek, R C; Maingi, N

    2004-07-14

    A laboratory trial to determine the efficacy of two methods in recovering known numbers of third-stage (L3) strongylid nematode larvae from herbage was carried out. Herbage samples consisting almost entirely of star grass (Cynodon aethiopicus) that had no L3 nematode parasitic larvae were collected at Onderstepoort, South Africa. Two hundred grams samples were placed in fibreglass fly gauze bags and seeded with third-stage strongylid nematode larvae at 11 different levels of herbage infectivity ranging from 50 to 8000 L3/kg. Eight replicates were prepared for each of the 11 levels of herbage infectivity. Four of these were processed using a modified automatic Speed Queen heavy-duty washing machine at a regular normal cycle, followed by isolation of larvae through centrifugation-flotation in saturated sugar solution. Larvae in the other four samples were recovered after soaking the herbage in water overnight and the larvae isolated with the Baermann technique of the washing. There was a strong correlation between the number of larvae recovered using both methods and the number of larvae in the seeded samples, indicating that the two methods give a good indication of changes in the numbers of larvae on pasture if applied in epidemiological studies. The washing machine method recovered higher numbers of larvae than the soaking and Baermann method at all levels of pasture seeding, probably because the machine washed the samples more thoroughly and a sugar centrifugation-flotation step was used. Larval suspensions obtained using the washing machine method were therefore cleaner and thus easier to examine under the microscope. In contrast, the soaking and Baermann method may be more suitable in field-work, especially in places where resources and equipment are scarce, as it is less costly in equipment and less labour intensive. Neither method recovered all the larvae from the seeded samples. The recovery rates for the washing machine method ranged from 18 to 41% while

  12. Hubungan keberadaan larva nyamuk Aedes Spp dengan kasus Demam Berdarah Dengue di Kota Bandung

    Directory of Open Access Journals (Sweden)

    Lukman Hakim

    2015-12-01

    Full Text Available Abstract. Bandung is the region with most cases of dengue hemorrhagic fever (DHF in West Java with 24,491 cases in the period 2009-2013. Dengue virus transmission occurs from DHF patients through the bite of Aedes aegypti and Ae. albopictus as the primary vector, while Ae. polynesiensis, Ae. scutellaris and Ae. (Finlayaniveus as secondary vectors. To determine the relationship of the presence of larvae of Aedes spp with DHF, has conducted research with larval survey and analysis of dengue cases in the city of Bandung. Research was carried out by recording DHF patients in the period 2011-2013, then visit to interview and survey of Aedes mosquito larvae in water containers inside and outside the home. Samples were successfully visited are 402 houses consist of 201 houses with DHF cases and 201 without DHF cases. The results showed that of 402 samples were obtained 75 positive of larvae of Aedes spp (house index/HI 18.7% consisted of 36 without DHF patient and 39 with DHF patient. Among the 8 villages research sites, highest HI is Cijaura village is 21.9%, and the lowest is village Manjahlega (11.1% (9 houses, while in the Cidurian village was  not found Aedes mosquitoes larvae. The most number of houses which positive of larvae of Aedes spp water containers are Sekejati village (37 houses, whereas the least was the Manjahlega village (2 houses. The results of chi square analysis and correlation, showed that there was no significant association between the presence of larvae of Aedes spp with DHF cases. Concluded, the presence of larvae of Aedes spp not significant associated with DHF cases in Bandung City, West Java. For the occurrence of dengue cases, beside the presence of Aedes spp, is also influenced by other factors such as the vector capacity, dengue virus virulence and host immune status. We recommended, to DHF control, beside conducting the control of dengue vector, is also needs to be carried out the other activities related to the

  13. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Science.gov (United States)

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  14. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Directory of Open Access Journals (Sweden)

    Thamara Figueiredo Procópio

    Full Text Available In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4, as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae and 1.03% (fed larvae. Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae, 61.7% of individuals emerged as adults. The extract (1.0% promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates

  15. Utilization Efficiency of Yolk Egg on Maanvis (Pterophyllum scalare Embryos and Larvae in Different Incubation Temperatures

    Directory of Open Access Journals (Sweden)

    T. Budiardi

    2007-01-01

    Full Text Available This study was performed to determine the efficiency of yolk egg utilization in embryos and larvae, hatching rate, incubation time to hatch, and growth rate of maanvis (Pterophyllum scalare larvae incubated at room remperature, 27oC, and 30oC.  Results of study showed that yolk egg utilization efficiency of embryos and larvae incubated at 30oC was 73.70% and 0,18%, respectively, and no different with that of room and 27oC incubation temperatures.  Hatching rate of eggs incubated at 30oC (84.75% was also same with that of other treatments.  However, incubation time to hatch (27.41 hours was shorter than that of other treatments.  The growth rate by length of larvae (2.16% and survival rate (75.28% incubated at 30oC was also higher compared with that of other treatments.  Thus, in general, optimum temperature for egg hatching and larval rearing of maanvis was 30oC. Keywords: maanvis, Pterophyllum scalare, egg yolk, larvae, embryo, temperature   ABSTRAK Penelitian ini dilakukan untuk mengetahui efisiensi pemanfaatan kuning telur pada embrio dan larva, derajat penetasan, lama inkubasi telur hingga menetas, dan laju pertumbuhan serta kelangsungan hidup larva ikan maanvis (Pterophyllum scalare yang diinkubasi pada suhu ruang, 27oC dan 30oC.  Hasil penelitian menunjukkan bahwa nilai efisiensi pemanfaatan kuning telur bila diinkubasi pada suhu 30oCsebesar 73,70% pada fase embrio dan 0,18% pada fase larva, dan tidak berbeda dengan suhu ruang dan 27oC.  Demikian juga dengan derajat penetasan telur  (84,75% tidak berbeda dengan perlakuan lainnya.  Sementara itu, lama inkubasi telur hingga menetas (27,41 jam lebih cepat dibandingkan dengan suhu inkubasi perlakuan lainnya. Demikian juga dengan laju pertumbuhan panjang (2,16% dan kelangsungan hidup larva (75,28% lebih tinggi dibandingkan dengan perlakuan lainnya. Dengan demikian, secara umum suhu optimal untuk penetasan dan pemeliharaan larva ikan maanvis adalah 30°C. Kata kunci: ikan maanvis

  16. Cryopreservation of third-stage larvae of Strongylus vulgaris (large strongyle of horses).

    Science.gov (United States)

    Titoy, G A; Van Rensburg, L J

    1997-06-01

    A technique for the cryopreservation of third-stage larvae of Strongylus vulgaris is described. Infective larvae of S. vulgaris were exsheathed in a 0.16% sodium hypochlorite solution and then transferred into cryotubes containing 0.09% saline. The samples were stored in the gas phase of liquid nitrogen.

  17. Live and formulated diet evaluation through initial growth and survival of jundiá larvae, Rhamdia quelen Alimento vivo e formulado, crescimento inicial e sobrevivência de pós-larvas de jundiá, Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Paulo César Falanghe Carneiro

    2003-12-01

    Full Text Available Live diet (LD dependence and the lack of suitable formulated diets (FD are major constraints for the expansion of larviculture of many fish species. The low digestibility and nutritional quality of FD are factors that might explain their failure as a stand-alone starter food. To determine whether FD in combination with LD (zooplankton may efficiently increase larval growth and survival of jundiá (Rhamdia quelen, when compared to fish fed by either types of diet alone, jundiá larvae (5.57 mm; 1.41 mg were initially stocked into 12 10-L aquaria (100 larvae per aquarium. Replicate groups (n=4 were fed ad libitum one of the three diets for 20 (when fed FD or 48 days (when fed LD or the combined diets. Larvae fed FD alone presented significantly lower survival and growth rates as compared to larvae fed LD or a combination of both (co-fed. In addition, co-fed larvae grew better (170 mg in relation to those fed solely with LD (110 mg. Such better performance of combined feeding indicates that most of the required nutrients are in balance when both diet sources are included. More can be learned about fish larvae nutrition by further testing the effect of feeding combined diets, which include zooplankton, than only testing new ingredients or protein sources commonly used in the elaboration of juvenile or adult fish feeds.A larvicultura da maioria das espécies de peixes enfrenta o desafio da dependência do alimento vivo (AL e da falta de dietas formuladas (DF que atendam plenamente às necessidades das larvas. A baixa digestibilidade e a qualidade nutricional das DFs são alguns dos fatores que explicam o insucesso quando as larvas recebem apenas FD. Para avaliar o efeito da combinação da DF com o AL no crescimento e na sobrevivência de larvas de jundiá (Rhamdia quelen, comparando com o uso separado da DF ou do AL, larvas recém eclodidas (5,57 mm; 1,41 mg foram estocadas inicialmente em 12 aquários de 10 L (100 larvas por aquário. Quatro r

  18. Tracking movement and temperature selection of larvae of two forensically important blow fly species within a "maggot mass".

    Science.gov (United States)

    Johnson, Aidan P; Wighton, Samuel J; Wallman, James F

    2014-11-01

    The current study responds to the lack of understanding about the temperatures experienced by individual blow fly larvae within "maggot masses." The temperature selection of both aggregating (in a mass) and nonaggregating larvae was compared and their pattern of movement assessed. Infrared imaging determined the temperatures within a mass and in the vicinity of the constituent individual larvae, whose movements were tracked by dyeing their tissues red. Individual Chrysomya rufifacies larvae selected temperatures above 27°C, significantly higher than the temperature selected by Calliphora vicina larvae (24.5°C). However, this same difference was not seen within a mass, with both species selecting temperatures around 28°C. Larval movement in a mass was nonrandom, indicating that larvae actively select their position in a mass. Furthermore, larvae have a strong tendency to select the hottest part of a mass; therefore, maximum mass temperatures might provide a reliable proxy for the actual temperatures experienced by larvae. © 2014 American Academy of Forensic Sciences.

  19. Prevalence of American Foulbrood and Paenibacillus Larvae Genotypes in Bulgaria

    OpenAIRE

    RUSENOVA, Nikolina; PARVANOV, Parvan

    2016-01-01

    This study aimed to analyse the prevalence of American foulbrood and Paenibacillus larvae genotypes in Bulgaria. For this purpose, data concerning American foulbrood outbreaks were used. Also, available data on the number of destroyed bee families covering a twenty-five-year period (1989 - 2013) was collected from the register of Bulgarian Food Safety Agency. In addition, Paenibacillus larvae genotypes in 15 apiaries were established by rep - PCR with BOXA1R and MBOREP1 primers. Results showe...

  20. Studies with normal and gamma irradiated third stage larvae of Oesophagostomum columbianum in lambs

    International Nuclear Information System (INIS)

    Sharma, R.L.; Dhar, D.N.

    1979-01-01

    Results of work on the host-parasite relationship of Oesophagostomum columbianum in sheep, carried out at the Regional Centre, Srinagar, are presented. Primary infections with small numbers of O. columbianum third larvae in lambs caused establishment of more adult worms in the intestine. As the number of larvae administered to lambs in primary infections was increased, a significant decrease in the establishment of adult worms in the intestine was observed. Higher levels of primary infections in lambs resulted in stunting of both male and female adult worms in intestine but this did not affect the resultant egg production by the worms. The severity of the disease in lambs was directly related to the number of larvae administered in primary infections. Attenuation of the third stage larvae of O.columbianum was obtained when they were irradiated at 40 and 50 Krad doses from a gamma source. Whereas it was possible to stimulate only a partial protection in young lambs to O. columbianum with a single dose of 2000, 40 Krad irradiated larvae. Vaccination with the same numbers of larvae, but irradiated at 50 Krad failed to protect the animals. The presence of adult worms of O.columbianum in sites outside the intestine in lambs has been reported for the first time. (auth.)

  1. Dipteran larvae and microbes facilitate nutrient sequestration in the Nepenthes gracilis pitcher plant host.

    Science.gov (United States)

    Lam, Weng Ngai; Chong, Kwek Yan; Anand, Ganesh S; Tan, Hugh Tiang Wah

    2017-03-01

    The fluid-containing traps of Nepenthes carnivorous pitcher plants (Nepenthaceae) are often inhabited by organisms known as inquilines. Dipteran larvae are key components of such communities and are thought to facilitate pitcher nitrogen sequestration by converting prey protein into inorganic nitrogen, although this has never been demonstrated in Nepenthes Pitcher fluids are also inhabited by microbes, although the relationship(s) between these and the plant is still unclear. In this study, we examined the hypothesis of digestive mutualism between N. gracilis pitchers and both dipteran larvae and fluid microbes. Using dipteran larvae, prey and fluid volumes mimicking in situ pitcher conditions, we conducted in vitro experiments and measured changes in available fluid nitrogen in response to dipteran larvae and microbe presence. We showed that the presence of dipteran larvae resulted in significantly higher and faster releases of ammonium and soluble protein into fluids in artificial pitchers, and that the presence of fluid microbes did likewise for ammonium. We showed also that niche segregation occurs between phorid and culicid larvae, with the former fragmenting prey carcasses and the latter suppressing fluid microbe levels. These results clarify the relationships between several key pitcher-dwelling organisms, and show that pitcher communities facilitate nutrient sequestration in their host. © 2017 The Author(s).

  2. Genetic and Biochemical Diversity of Paenibacillus larvae Isolated from Tunisian Infected Honey Bee Broods

    Directory of Open Access Journals (Sweden)

    Chadlia Hamdi

    2013-01-01

    Full Text Available Paenibacillus larvae is the causative agent of American foulbrood (AFB, a virulent disease of honeybee (Apis mellifera larvae. In Tunisia, AFB has been detected in many beekeeping areas, where it causes important economic losses, but nothing is known about the diversity of the causing agent. Seventy-five isolates of P. larvae, identified by biochemical tests and 16S rRNA gene sequencing, were obtained from fifteen contaminated broods showing typical AFB symptoms, collected in different locations in the northern part of the country. Using BOX-PCR, a distinct profile of P. larvae with respect to related Paenibacillus species was detected which may be useful for its identification. Some P. larvae-specific bands represented novel potential molecular markers for the species. BOX-PCR fingerprints indicated a relatively high intraspecific diversity among the isolates not described previously with several molecular polymorphisms identifying six genotypes on polyacrylamide gel. Polymorphisms were also detected in several biochemical characters (indol production, nitrate reduction, and methyl red and oxidase tests. Contrary to the relatively high intraspecies molecular and phenotypic diversity, the in vivo virulence of three selected P. larvae genotypes did not differ significantly, suggesting that the genotypic/phenotypic differences are neutral or related to ecological aspects other than virulence.

  3. Survival dynamics of scleractinian coral larvae and implications for dispersal

    Science.gov (United States)

    Graham, E. M.; Baird, A. H.; Connolly, S. R.

    2008-09-01

    Survival of pelagic marine larvae is an important determinant of dispersal potential. Despite this, few estimates of larval survival are available. For scleractinian corals, few studies of larval survival are long enough to provide accurate estimates of longevity. Moreover, changes in mortality rates during larval life, expected on theoretical grounds, have implications for the degree of connectivity among reefs and have not been quantified for any coral species. This study quantified the survival of larvae from five broadcast-spawning scleractinian corals ( Acropora latistella, Favia pallida, Pectinia paeonia, Goniastrea aspera, and Montastraea magnistellata) to estimate larval longevity, and to test for changes in mortality rates as larvae age. Maximum lifespans ranged from 195 to 244 d. These longevities substantially exceed those documented previously for coral larvae that lack zooxanthellae, and they exceed predictions based on metabolic rates prevailing early in larval life. In addition, larval mortality rates exhibited strong patterns of variation throughout the larval stage. Three periods were identified in four species: high initial rates of mortality; followed by a low, approximately constant rate of mortality; and finally, progressively increasing mortality after approximately 100 d. The lifetimes observed in this study suggest that the potential for long-distance dispersal may be substantially greater than previously thought. Indeed, detection of increasing mortality rates late in life suggests that energy reserves do not reach critically low levels until approximately 100 d after spawning. Conversely, increased mortality rates early in life decrease the likelihood that larvae transported away from their natal reef will survive to reach nearby reefs, and thus decrease connectivity at regional scales. These results show how variation in larval survivorship with age may help to explain the seeming paradox of high genetic structure at metapopulation scales

  4. Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae).

    Science.gov (United States)

    Lang, Andreas; Otto, Mathias

    2015-08-31

    Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles.

  5. Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae

    Directory of Open Access Journals (Sweden)

    Andreas Lang

    2015-08-01

    Full Text Available Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles.

  6. Looking for Larvae Above an Erupting Submarine Volcano, NW Rota-1, Mariana Arc

    Science.gov (United States)

    Beaulieu, S.; Hanson, M.; Tunnicliffe, V.; Chadwick, W. W., Jr.; Breuer, E. R.

    2016-02-01

    In 2009 the first marine protected areas for deep-sea hydrothermal vents in U.S. waters were established as part of the Volcanic Unit of the Marianas Trench Marine National Monument. In this region, hydrothermal vents are located along the Mariana Arc and back-arc spreading center. In particular hydrothermal vents are located near the summit of NW Rota-1, an active submarine volcano on the Mariana Arc which was erupting between 2003 and 2010 and ceased as of 2014. NW Rota-1 experienced a massive landslide in late 2009, decimating the habitat on the southern side of the volcano. This project looked at zooplankton tow samples taken from the water column above NW Rota-1 in 2010, searching for larvae which have the potential to recolonize the sea floor after such a major disturbance. Samples were sorted in entirety into coarse taxa, and then larvae were removed for DNA barcoding. Overall zooplankton composition was dominated by copepods, ostracods, and chaetognaths, the majority of which are pelagic organisms. Comparatively few larvae of benthic invertebrates were found, but shrimp, gastropod, barnacle, and polychaete larvae did appear in low numbers in the samples. Species-level identification obtained via genetic barcoding will allow for these larvae to be matched to species known to inhabit the benthic communities at NW Rota-1. Identified larvae will give insight into the organisms which can re-colonize the seafloor vent communities after a disturbance such as the 2009 landslide. Communities at hydrothermal vents at other submarine volcanoes in the Monument may act as sources for these larvae, but connectivity in this region of complex topography is unknown. As the microinvertebrate biodiversity in the Monument has yet to be fully characterized, our project also provides an opportunity to better describe both the zooplankton and benthic community composition in this area of the Monument.

  7. A preliminary account on the distribution of decapod larvae in the Konkan waters

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.; Nair, S.R.S.

    Decapod larval distribution in Konkan coastal waters was studied during the premonsoon season (March-April). Sergestid was the largest group forming 80.55% of the total decapod crustacean larvae. Penaeid larvae constituted only 0.65% and M. dobsoni...

  8. Stereoselectivity in bioaccumulation and excretion of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae.

    Science.gov (United States)

    Lv, Xiaotian; Liu, Chen; Li, Yaobin; Gao, Yongxin; Wang, Huili; Li, Jianzhong; Guo, Baoyuan

    2014-09-01

    Stereoselectivity in bioaccumulation and excretion of stereoisomers of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae through dietary exposure was investigated. Liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method that use a ChiralcelOD-3R[cellulosetris-Tris-(3, 5-dichlorophenyl-carbamate)] chromatography column was applied to carry out chiral separation of the stereoisomers. Wheat bran was spiked with racemic epoxiconazole at two dose levels of 20mg/kg and 2mg/kg (dry weight) to feed T. molitor larvae. The results showed that both the doses of epoxiconazole were taken up by Tenebrio molitor larvae rapidly at the initial stages. There was a significant trend of stereoselective bioaccumulation in the larvae with a preferential accumulation of (-)-epoxiconazole in the 20mg/kg dose. The stereoselectivity in bioaccumulation in the 2mg/kg dosage was not obvious compared to the 20mg/kg group. Results of excretion indicated an active excretion is an important pathway for the larvae to eliminate epoxiconazole which was a passive transport process with non stereoselectivity. The faster elimination might be the reason for the low accumulation of epoxiconazole, as measured by bioaccumulation factor (BAF). Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Sustainable production of housefly (Musca domestica) larvae as a protein-rich feed ingredient by utilizing cattle manure

    Science.gov (United States)

    Hussein, Mahmoud; Pillai, Viju V.; Goddard, Joshua M.; Park, Hui G.; Kothapalli, Kumar S.; Ross, Deborah A.; Ketterings, Quirine M.; Brenna, J. Thomas; Milstein, Mark B.; Marquis, Helene; Johnson, Patricia A.; Nyrop, Jan P.

    2017-01-01

    The common housefly, Musca domestica, is a considerable component of nutrient recycling in the environment. Use of housefly larvae to biodegrade manure presents an opportunity to reduce waste disposal while the rapidly assimilated insect biomass can also be used as a protein rich animal feed. In this study, we examine the biodegradation of dairy cattle manure using housefly larvae, and the nutritional value of the resulting larva meal as a feed ingredient. Our results demonstrated that dairy cattle manure presents a balanced substrate for larval growth, and the spent manure showed reductions in concentration of total nitrogen (24.9%) and phosphorus (6.2%) with an overall reduction in mass. Larva yield at an optimum density was approximately 2% of manure weight. Nutritional analysis of M. domestica larva meal showed values comparable to most high protein feed ingredients. Larva meal was 60% protein with a well-balanced amino acid profile, and 20% fat with 57% monounsaturated fatty acids, and 39% saturated fatty acids. Larva meal lacked any significant amount of omega-3 fatty acids. Evaluation of micronutrients in larva meal suggested that it is a good source of calcium and phosphorus (0.5% and 1.1% respectively). The nutritional value of larva meal closely matches that of fishmeal, making it a potentially attractive alternative for use as a protein-rich feed ingredient for livestock and aquaculture operations. PMID:28170420

  10. Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    M. Angélica Garrido-Pereira

    2014-11-01

    Full Text Available Cobia (Rachycentron canadum is a marine finfish with good potential for mariculture. This study analyzes the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS. Larvae were stocked into two independent RAS for 26 days after hatching. One of the systems (Probiotic treatment received the addition of a commercial probiotic consisting of B. subtilis, B. licheniformis and B. pumilus directly into the water and by live feed. Survival, final weight and water quality were not affected by probiotics. Results showed larvae of the probiotic treatment demonstrated a greater resistance to salinity stress. Immunohistochemical analysis showed a higher expression of CD4 in probiotic treatment. These results suggest that Bacillus spp. probiotics used in RAS have a potential stimulating impact on immune system differentiation and increases salinity stress resistance of cobia larvae.

  11. Gastrointestinal symptoms resembling ulcerative proctitis caused by larvae of the drone fly Eristalis tenax.

    Science.gov (United States)

    Desoubeaux, Guillaume; Gaillard, Julien; Borée-Moreau, Diane; Bailly, Éric; Andres, Christian R; Chandenier, Jacques

    2014-04-01

    We report a case of facultative intestinal myiasis due to larvae of the drone fly Eristalis tenax, also named the rat-tailed maggots. The development of larvae in the lower bowel was responsible for non-specific gastrointestinal symptoms that resembled ulcerative proctitis. The diagnosis was established upon the observation of four spontaneously excreted mobile larvae. The definite identification of the E. tenax species was made possible by scanning electron microscopy. The clinical outcome was satisfactory.

  12. Uncommon Human Urinary Tract Myiasis Due to Psychoda Sp. Larvae, Kashan, Iran: A Case Report.

    Science.gov (United States)

    Rasti, Sima; Dehghani, Rouhullah; Khaledi, Hassan Naeimi; Takhtfiroozeh, Sayed Mahdi; Chimehi, Elahe

    2016-01-01

    Contamination of human and animal body tissues with flies' larvae and diptera cause myiasis. A 26 yr old female patient refers to Kashan Shahid Beheshti Hospital, central Iran because of urogenital infection, pain in the right part of stomach, smelly and reddish vaginal discharge and frequent urination. In the first checking, urine sample was taken. In the sample, active and alive larvae were seen. The live samples were taken to the Environmental Health Department Lab of Kashan University of Medical Sciences in clean glass jars. In the morphological survey, Psychoda sp larvae were identified. In Iran, this study is the first report of this species of larva that causes urinary myiasis. This fly larva is not carnivore or bloodsucker and feeds on bacterial agents. Observance of personal hygiene especially during defecation and urination is essential to prevent contamination of this type of myiasis.

  13. Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

    Directory of Open Access Journals (Sweden)

    Sacchi L.

    2001-06-01

    Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

  14. Inclusion of copepod Acartia tonsa nauplii in the feeding of Centropomus undecimalis larvae increases stress resistance

    Directory of Open Access Journals (Sweden)

    Wanessa de Melo-Costa

    2015-09-01

    Full Text Available This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1; A. tonsa nauplii (0.25 to 0.5 mL-1 and rotifers (5 to 7.5 mL-1, and A. tonsa nauplii (0.12 to 0.25 mL-1. The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively and resisted more heat stress (87.4% than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.

  15. Caffeine administration alters the behaviour and development of Galleria mellonella larvae.

    Science.gov (United States)

    Maguire, Ronan; Kunc, Martin; Hyrsl, Pavel; Kavanagh, Kevin

    2017-11-01

    The effect of feeding caffeine on the behaviour and neural proteome of Galleria mellonella larvae was assessed. Caffeine was administered to larvae by force feeding and the metabolites theobromine and theophylline were subsequently detected by RP-HPLC analysis. Administration of caffeine to larvae resulted in reduced movement and a reduction in the formation of pupae. The production of the muscle relaxant theophylline may contribute to the reduction in larval movement. Analysis of the changes in proteome of the brain and surrounding tissues of caffeine fed larvae revealed an increase in the abundance of immune related proteins such as immune-related Hdd1 (6.28 fold increase) and hemolin (1.68 fold increase), ATPase associated proteins such as H+ transporting ATP synthase O subunit isoform 1 (1.87 fold increase) and H+ transporting ATP synthase delta subunit (1.53 fold increase) and proteins indicative of brain trauma such as troponin T transcript variant B, partial (1.55 fold increase). Proteins involved in development and protein degradation such as SUMO-activating enzyme subunit 1 (3.08 fold decrease) and chitin deacetylase, partial (3.67 fold decrease) were decreased in abundance. The results presented here indicate that caffeine is metabolised in a similar way in G. mellonella larvae to that in mammals and results in a variety of behavioural and developmental alterations. Utilisation of insects for studying the effects of caffeine and other neuroactive compounds may offer new insights into their mode of action and reduce the need to use mammals for this type of analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Hemolymph amino acid analysis of individual Drosophila larvae.

    Science.gov (United States)

    Piyankarage, Sujeewa C; Augustin, Hrvoje; Grosjean, Yael; Featherstone, David E; Shippy, Scott A

    2008-02-15

    One of the most widely used transgenic animal models in biology is Drosophila melanogaster, the fruit fly. Chemical information from this exceedingly small organism is usually accomplished by studying populations to attain sample volumes suitable for standard analysis methods. This paper describes a direct sampling technique capable of obtaining 50-300 nL of hemolymph from individual Drosophila larvae. Hemolymph sampling performed under mineral oil and in air at 30 s intervals up to 120 s after piercing larvae revealed that the effect of evaporation on amino acid concentrations is insignificant when the sample was collected within 60 s. Qualitative and quantitative amino acid analyses of obtained hemolymph were carried out in two optimized buffer conditions by capillary electrophoresis with laser-induced fluorescence detection after derivatizing with fluorescamine. Thirteen amino acids were identified from individual hemolymph samples of both wild-type (WT) control and the genderblind (gb) mutant larvae. The levels of glutamine, glutamate, and taurine in the gb hemolymph were significantly lower at 35%, 38%, and 57% of WT levels, respectively. The developed technique that samples only the hemolymph fluid is efficient and enables accurate organism-level chemical information while minimizing errors associated with possible sample contaminations, estimations, and effects of evaporation compared to the traditional hemolymph-sampling techniques.

  17. Insect Larvae: A New Platform to Produce Commercial Recombinant Proteins.

    Science.gov (United States)

    Targovnik, Alexandra M; Arregui, Mariana B; Bracco, Lautaro F; Urtasun, Nicolas; Baieli, Maria F; Segura, Maria M; Simonella, Maria A; Fogar, Mariela; Wolman, Federico J; Cascone, Osvaldo; Miranda, Maria V

    2016-01-01

    In Biotechnology, the expression of recombinant proteins is a constantly growing field and different hosts are used for this purpose. Some valuable proteins cannot be produced using traditional systems. Insects from the order Lepidoptera infected with recombinant baculovirus have appeared as a good choice to express high levels of proteins, especially those with post-translational modifications. Lepidopteran insects, which are extensively distributed in the world, can be used as small protein factories, the new biofactories. Species like Bombyx mori (silkworm) have been analyzed in Asian countries to produce a great number of recombinant proteins for use in basic and applied science and industry. Many proteins expressed in this larva have been commercialized. Several recombinant proteins produced in silkworms have already been commercialized. On the other hand, species like Spodoptera frugiperda, Heliothis virescens, Rachiplusia nu, Helicoverpa zea and Trichoplusia ni are widely distributed in both the occidental world and Europe. The expression of recombinant proteins in larvae has the advantage of its low cost in comparison with insect cell cultures. A wide variety of recombinant proteins, including enzymes, hormones and vaccines, have been efficiently expressed with intact biological activity. The expression of pharmaceutically proteins, using insect larvae or cocoons, has become very attractive. This review describes the use of insect larvae as an alternative to produce commercial recombinant proteins.

  18. Distribution patterns and predilection muscles of Trichinella zimbabwensis larvae in experimentally infected Nile crocodiles (Crocodylus niloticus Laurenti

    Directory of Open Access Journals (Sweden)

    Louis J. La Grange

    2014-02-01

    Full Text Available No controlled studies have been conducted to determine the predilection muscles of Trichinella zimbabwensis larvae in Nile crocodiles (Crocodylus niloticus or the influence of infection intensity on the distribution of the larvae in crocodiles. The distribution of larvae in muscles of naturally infected Nile crocodiles and experimentally infected caimans (Caiman crocodilus and varans (Varanus exanthematicus have been reported in literature. To determine the distribution patterns of T. zimbabwensis larvae and predilection muscles, 15 crocodiles were randomly divided into three cohorts of five animals each, representing high infection (642 larvae/kg of bodyweight average, medium infection (414 larvae/kg of bodyweight average and low infection (134 larvae/kg of bodyweight average cohorts. In the high infection cohort, high percentages of larvae were observed in the triceps muscles (26% and hind limb muscles (13%. In the medium infection cohort, high percentages of larvae were found in the triceps muscles (50%, sternomastoid (18% and hind limb muscles (13%. In the low infection cohort, larvae were mainly found in the intercostal muscles (36%, longissimus complex (27%, forelimb muscles (20% and hind limb muscles (10%. Predilection muscles in the high and medium infection cohorts were similar to those reported in naturally infected crocodiles despite changes in infection intensity. The high infection cohort had significantly higher numbers of larvae in the sternomastoid, triceps, intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles (p < 0.05 compared with the medium infection cohort. In comparison with the low infection cohort, the high infection cohort harboured significantly higher numbers of larvae in all muscles (p < 0.05 except for the tongue. The high infection cohort harboured significantly higher numbers of larvae (p < 0.05 in the sternomastoid, triceps, intercostal, longissimus complex

  19. Ovos de Toxocara sp. e larvas de Ancylostoma sp. em praça pública de Lavras, MG Toxocara sp. eggs and Ancylostoma sp. larva in public parks, Brazil

    Directory of Open Access Journals (Sweden)

    Antônio Marcos Guimarães

    2005-04-01

    Full Text Available Larva migrans visceral e cutânea são zoonoses parasitárias causadas pela infecção da larva de Toxocara sp. e Ancylostoma sp., respectivamente. O objetivo do estudo foi verificar a contaminação por ovos de Toxocara sp. e ovos e larvas de Ancylostoma sp. em amostras de solos coletadas de praças públicas e de áreas de recreação infantil de Lavras, Estado de Minas Gerais, por meio da técnica de centrífugo-flutuação e do método de Baermann. A ocorrência de ovos de Toxocara sp. e, ovos e larvas de Ancylostoma sp. foi observada em 69,6% (16/23 das amostras de solo coletadas de praças públicas. A contaminação somente por ovos de Ancylostoma sp. em amostras de solo coletadas em escolas/creches foi de 22,2% (4/18. A percentagem de amostras de areia coletadas de escolas/creches contaminadas somente com larvas de Ancylostoma sp. foi de 11,1% (2/18. Praças públicas são as áreas com maior risco potencial de infecção por Toxocara sp. e Ancylostoma sp. Exame coproparasitológico realizado em 174 amostras de fezes de cães observou 58% e 23%, respectivamente, com ovos de Ancylostoma sp. e Toxocara sp.Visceral and cutaneous larva migrans are parasitic zoonoses caused by the infection of larval nematodes Toxocara sp. and Ancylostoma sp. respectively. The objective of this study was to investigate the contamination by Toxocara sp. eggs and Ancylostoma sp. eggs and larva of soil samples collected from public parks and children's playground areas in state of Minas Gerais, Brazil, using both Baermann's method and centrifugal flotation technique. Toxocara sp. and Ancylostoma sp. eggs were observed in soil samples collected from public squares in 17.4% (4/23 and 69.6 (16/23 respectively. In schools and child day care settings the contamination by Ancylostoma sp. larva in sand samples was 11.1% (2/18. Public parks are settings of more potential risk of Toxocara sp. eggs and Ancylostoma sp. infection. Stool parasitology testing of 174 stool

  20. Influence of nutrient substrates on the expression of cellulases in Cerambyx cerdo L. (Coleoptera: Cerambycidae larvae

    Directory of Open Access Journals (Sweden)

    Pavlović R.

    2012-01-01

    Full Text Available The expression and distribution of digestive cellulases along the midgut of Cerambyx cerdo larvae were analyzed for the first time and are presented in this article. Four groups of larvae were examined: larvae developed in the wild; larvae taken from the wild and successively reared on an artificial diet based on polenta; and larvae hatched in the laboratory and reared on two different artificial diets. Seven endocellulase and seven β-D-glucosidase isoforms were detected in all midgut extracts of C. cerdo with a zymogram after native PAGE. We observed that C. cerdo larvae are capable of producing cellulase isoforms with different PAGE mobilities depending on the nutrient substrate. From our findings it can be assumed that, depending on the distribution of endocellulase and β-D-glucosidase, cellulose molecules are first fragmented in the anterior and middle midgut by endo-β-1,4-glucanase; subsequently, the obtained fragments are broken down by β-D-glucosidase mostly in middle midgut.

  1. The hatching larva of the priapulid worm Halicryptus spinulosus

    Directory of Open Access Journals (Sweden)

    Budd Graham E

    2009-05-01

    Full Text Available Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

  2. Effects of irradiation of Bombyx mori larvae on the evolution of ecdysteroid titer in haemolymph and ecdysone metabolism

    International Nuclear Information System (INIS)

    Coulon, Madeleine; Feyereisen, Rene

    1977-01-01

    Second and third instar larvae of B. mori show a peak of ecdysteroids in the haemolymph towards the end of each instar. Second instar larvae which are X-ray treated at 0 h die at the third ecdysis. In these larvae, titer and metabolism of ecdysone is disturbed. Larvae X-ray treated at 24h in the second instar mostly become permanent larvae of the third instar, having a very low level of circulating ecdysteroids, which hardly metabolize injected ecdysone [fr

  3. Effect of ivermectin on the larvae of Anopheles gambiae and Culex quinquefasciatus

    DEFF Research Database (Denmark)

    Derua, Yahya A.; Malongo, Bernard B.; Simonsen, Paul E.

    2016-01-01

    . Methods: A total of 1800 laboratory reared mosquito larvae of each species were used in the bioassays. Twelve replicates were performed, each testing 6 concentrations of ivermectin (0.0, 0.001, 0.01, 0.1, 1.0 and 10.0 parts per million (ppm)) against third instar larvae of An. gambiae and Cx...

  4. Early larvae ontogeny of the Neotropical fishes: Prochilodus costatus and P. argenteus (Characiformes: Prochilodontidae).

    Science.gov (United States)

    dos Santos, José Enemir; Sales, Naiara Guimarães; dos Santos, Marcella Lourenço; Arantes, Fábio Pereira; Godinho, Hugo Pereira

    2016-06-01

    Early development of fish larvae is a highly dynamic process and its study may provide important information about ontogenetic development, bioenergetic growth, behaviour, taxonomic characteristics for identification in natural environments, identification of spawning areas, and population monitoring. With the aim to provide knowledge about their growth and behaviour, to support larval rearing, and also taxonomic purposes, we studied the life history of the Prochilodus argenteus and P. costatus from hatching until the complete absorption of the yolk. Larvae were obtained through artificial reproduction at the Hydrobiology and Aquaculture Station of Três Marias, Minas Gerais, Brazil. Immediately after hatching, 100 larvae of each species were put in two plastic incubators for conditioning. On a daily basis, larvae behavior was recorded and 14 larvae of each species were collected to analyse body morphology. On the first day after hatching, larvae of P. costatus and P. argenteus showed an elongated and transparent body; the yolk sac was filled with individualized yolk globules. In both species, the embryonic fin rounded the caudal region of the body, the retina was non-pigmented and the gut was obliterated. At the second day post-hatching, larvae of both species dendritic chromatophores had emerged, the mouth was obliterated and the pectoral fin was observed. The larvae showed 38-43 myomeres in P. costatus and 42-43 in P. argenteus. For both species, the gas bladder was inflated and the lumen of the gut was already open. On the third day post-hatching, the mouth of P. costatus and P. argenteus was already open in a sub-terminal position; the retina was pigmented; the gill arches had lamellar protrusions and were partially covered by the operculum. On the fourth day post-hatching, the pigmentation pattern was maintained with greater intensity; the mouth occupied a terminal position, the yolk sac was almost completely reabsorbed, and the pectoral and caudal fins

  5. A note on the record of Rastrelliger (Mackerel) larvae from the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Peter, K.J.

    from Gulf of Thailand and South China Sea They resemble the larvae of a scombrid relative, the Pacific mackerel Pneumatophorous diego, but differ in having less pigmentation and deeper body The larvae have a fairly stubby body, with 30 myomeres big eyes...

  6. siRNA transfection in larvae of the barnacle Amphibalanus amphitrite

    KAUST Repository

    Zhang, G.

    2015-06-25

    RNA interference (RNAi) provides an efficient and specific technique for functional genomic studies. Yet, no successful application of RNAi has been reported in barnacles. In this study, siRNA against p38 MAPK was synthesized and then transfected into A. amphitrite larvae at either the nauplius or cyprid stage, or at both stages. Effects of siRNA transfection on the p38 MAPK level were hardly detectable in the cyprids when they were transfected at the nauplius stage. In contrast, larvae that were transfected at the cyprid stage showed lower levels of p38 MAPK than the blank and reagent controls. However, significantly decreased levels of phosphorylated p38 MAPK (pp38 MAPK) and reduced settlement rates were observed only in ‘double transfections’, in which larvae were exposed to siRNA solution at both the nauplius and cyprid stages. A relatively longer transfection time and more larval cells directly exposed to siRNA might explain the higher efficiency of double transfection experiments.

  7. siRNA transfection in larvae of the barnacle Amphibalanus amphitrite

    KAUST Repository

    Zhang, G.; He, L.-S.; Wong, Y. H.; Yu, L.; Qian, P.-Y.

    2015-01-01

    RNA interference (RNAi) provides an efficient and specific technique for functional genomic studies. Yet, no successful application of RNAi has been reported in barnacles. In this study, siRNA against p38 MAPK was synthesized and then transfected into A. amphitrite larvae at either the nauplius or cyprid stage, or at both stages. Effects of siRNA transfection on the p38 MAPK level were hardly detectable in the cyprids when they were transfected at the nauplius stage. In contrast, larvae that were transfected at the cyprid stage showed lower levels of p38 MAPK than the blank and reagent controls. However, significantly decreased levels of phosphorylated p38 MAPK (pp38 MAPK) and reduced settlement rates were observed only in ‘double transfections’, in which larvae were exposed to siRNA solution at both the nauplius and cyprid stages. A relatively longer transfection time and more larval cells directly exposed to siRNA might explain the higher efficiency of double transfection experiments.

  8. Uncommon Human Urinary Tract Myiasis Due to Psychoda Sp. Larvae, Kashan, Iran: A Case Report

    Directory of Open Access Journals (Sweden)

    Sima RASTI

    2016-10-01

    Full Text Available Contamination of human and animal body tissues with flies’ larvae and diptera cause myiasis. A 26 yr old female patient refers to Kashan Shahid Beheshti Hospital, central Iran because of urogenital infection, pain in the right part of stomach, smelly and reddish vaginal discharge and frequent urination. In the first checking, urine sample was taken. In the sample, active and alive larvae were seen. The live samples were taken to the Environmental Health Department Lab of Kashan University of Medical Sciences in clean glass jars. In the morphological survey, Psychoda sp larvae were identified. In Iran, this study is the first report of this species of larva that causes urinary myiasis. This fly larva is not carnivore or bloodsucker and feeds on bacterial agents. Observance of personal hygiene especially during defecation and urination is essential to prevent contamination of this type of myiasis.

  9. Cholesterol oxidase interference on the emergence and viability of cotton boll weevil larvae

    Directory of Open Access Journals (Sweden)

    Santos Roseane Cavalcanti

    2002-01-01

    Full Text Available The aim of this work was to evaluate the influence of the enzyme cholesterol oxidase (Coase on emergence and viability of larvae of the cotton boll weevil (Anthonomus grandis Boheman, 1843. A series of bioassays was performed with eggs and neonate larvae exposed to different enzyme concentrations in artificial diet. Larval survival was affected at all enzyme concentrations tested, and the six-day LD50 was 53 mug/mL (CI 95%: 43-59. Coase also interfered with hatching of larvae after eggs were floated for 15 min in Coase solution at different concentrations. Observations at the light and electronic microscopic level of midguts from larvae fed on artificial diet containing 53 mug/mL of Coase and collected at six days revealed highly vacuolated regions in the epithelial cells as well as partial degradation of the basal membrane and microvilli.

  10. Hyperprolinemic larvae of the drosophilid fly, Chymomyza costata, survive cryopreservation in liquid nitrogen.

    Science.gov (United States)

    Kostál, Vladimír; Zahradnícková, Helena; Šimek, Petr

    2011-08-09

    The larva of the drosophilid fly, Chymomyza costata, is probably the most complex metazoan organism that can survive submergence in liquid nitrogen (-196 °C) in a fully hydrated state. We examined the associations between the physiological and biochemical parameters of differently acclimated larvae and their freeze tolerance. Entering diapause is an essential and sufficient prerequisite for attaining high levels of survival in liquid nitrogen (23% survival to adult stage), although cold acclimation further improves this capacity (62% survival). Profiling of 61 different metabolites identified proline as a prominent compound whose concentration increased from 20 to 147 mM during diapause transition and subsequent cold acclimation. This study provides direct evidence for the essential role of proline in high freeze tolerance. We increased the levels of proline in the larval tissues by feeding larvae proline-augmented diets and found that this simple treatment dramatically improved their freeze tolerance. Cell and tissue survival following exposure to liquid nitrogen was evident in proline-fed nondiapause larvae, and survival to adult stage increased from 0% to 36% in proline-fed diapause-destined larvae. A significant statistical correlation was found between the whole-body concentration of proline, either natural or artificial, and survival to the adult stage in liquid nitrogen for diapause larvae. Differential scanning calorimetry analysis suggested that high proline levels, in combination with a relatively low content of osmotically active water and freeze dehydration, increased the propensity of the remaining unfrozen water to undergo a glass-like transition (vitrification) and thus facilitated the prevention of cryoinjury.

  11. Toxocara cati larva migrans in domestic pigs--detected at slaughterhouse control in Norway.

    Science.gov (United States)

    Davidson, Rebecca K; Mermer, Anna; Øines, Øivind

    2012-11-21

    Routine Trichinella meat inspection at the slaughterhouse detected one larva in a pooled batch of 100 pig samples. The larva was sent to the Norwegian Veterinary Institute (NVI) for species identification.Morphological examination revealed that the larva was not Trichinella spp. Molecular analysis was performed. PCR and sequencing of 5S/ITS identified the larva as Toxocara cati. A second round of digests was carried out at the meat inspection laboratory, in smaller batches to try to identify the infected animal. No further larvae were detected and it was not possible to identify which of the 100 animals the larva had come from. This is the first time that Toxocara cati has been reported in slaughterhouse pigs in Norway.Although the infected individual could not be identified, the meat originated from one of six potential farms. A small survey regarding rodent control and cats was sent to each of these farms. Cats had restricted access to food storage areas (two farms reported that cats had access) whilst none of the farms allowed cats into the production housing. Cats were, however, present on all the farms (mostly stray cats of unknown health status). Half of the farms also reported seeing rodents in the pig housing during the previous six months and half reported finding rodents in the feed and straw storage areas. We were unable to narrow down the source of infection - however contamination of food or bedding material, with cat faeces or infected rodents, in addition to the presence of infected rodents in pig housing remain potential routes of infection.

  12. Food and feeding ecology of Brazilian sardine (Sardinella brasiliensis larvae from the southeastern Brazilian Bight

    Directory of Open Access Journals (Sweden)

    Frederico W. Kurtz

    2001-01-01

    Full Text Available Results from depth integrated and vertically stratified plankton samples collected in the southeastern Brazilian Bight were used to study the feeding behavior of Brazilian sardine (Sardinella brasiliensis larvae. Sampling of the ichthyoplankton was carried out with 60 cm Bongo nets in the Bight during the spawning seasons of 1991/92 and 1992/93. The sampling of microzooplankton was carried out in the coastal region off Ubatuba, using the closing-type plankton net, in December 1995. The feeding study was based on a total of 901 captured larvae. Gut content analysis of the sardine larvae showed a diurnal pattern of food intake. Copepod nauplii dominated the diet of the preflexion and flexion larvae, but they were the second in abundance for the postflexion larvae which fed preferentially on copepodites and adults of Oncaea spp. Averaged feeding incidence of the 901 larvae was 37.6%, but it increased to 58.5% for day-caught larvae. Seventy percent of the food particles were found in the mid-gut and food eaten showed a natural increase in digestion from fore-gut to hind-gut. Vertical distribution of microzooplankton revealed that copepod nauplii were present in densities of 10-20 ind. L-1, mainly in the upper mixed layer (0-20 m depth, but higher densities of copepodite and adult of Oncaea, Oithona and Paracalamis were found within and beneath the thermocline. These results show that Brazilian sardine larvae can successfully adapt their diet, feeding on the most abundant food particles in the upper mixed layer of the survey area.Plâncton amostrado na região sudeste do Brasil, em coletas integradas verticalmente e estratificadas, foi utilizado no estudo do comportamento alimentar das larvas de sardinha-verdadeira (Sardinella brasiliensis. As coletas de ictioplâncton foram realizadas com rede tipo Bongo de 60 cm de diâmetro durante os períodos de desova de 1991/92 e 1992/93. Microzooplâncton foi amostrado na região costeira ao largo de Ubatuba

  13. Gregarious settlement in cypris larvae: the effects of cyprid age and assay duration

    NARCIS (Netherlands)

    Head, R.M.; Berntsson, K.M.; Dahlström, M.; Overbeke, J.C.; Thomason, J.C.

    2004-01-01

    Gregarious behaviour of marine larvae is perhaps most clearly associated with finding a suitable habitat in a changeable or restricted environment, or with finding other conspecifics with which to mate. Prior work has shown that in settlement assays using cypris larvae of the barnacle Balanus

  14. The Effect of Water Content of Medium Containing Oryctes rhinoceros Larvae on Metarhizium anisopliae Pathogenicity

    Directory of Open Access Journals (Sweden)

    Dyah Rini Indriyanti

    2017-08-01

    Full Text Available The entomopathogenic fungus, Metarhizium anisopliae (Metschnikoff Sorokin (Ascomycota: Hypocrealeswould effectively infect the target host on the appropriate medium water content. The aim of this study was to analyze the influence of water content of medium on the effectiveness of M. anisopliae fungus infection on O. rhinoceros larvae in the laboratory. Fifty healthy third instar larvae of O. rhinoceros were  obtained from field. The M. anisopliae obtained from Estate Crop Protection Board in Salatiga. The conidia density and viability of M. anisopliae were examined before used. The medium for maintaining the larva was the sawdust that had been sterilized. A total of 50 plastic cups were prepared to place 50 larvae (1 larva/cup. Each cup was filled with 100 g medium  of sawdust plus 2 g of M. anisopliae which was then stirred until mixed, with different water content: P1 (20%, P2 (40%, P3 (60%, P4 (80% and P5 (98%. The result indicated that  the water content of the medium affected the effectiveness of M. anisopliae fungus infection on O. rhinoceros larvae. The water content influenced the duration of larval mortality at each treatment. An important finding in this study is that controlling O. rhineceros larvae  with M. anisopliae can be done by manipulating the water content of medium. The benefit of this study may be used for the recommendation of O. rhinoceros pest control using M. anisopliae  with an effective water media content.

  15. Methodical aspects of rearing decapod larvae, Pagurus bernhardus (Paguridae) and Carcinus maenas (Portunidae)

    Science.gov (United States)

    Dawirs, R. R.

    1982-12-01

    Improved methods for experimental rearing of Pagurus bernhardus and Carcinus maenas larvae are presented. Isolated maintenance was found essential for reliable statistical evaluation of results obtained from stages older than zoea-1. Only by isolated rearing is it possible to calculate mean values ±95% confidence intervals of stage duration. Mean values (without confidence intervals) can only be given for group-reared larvae if mortality is zero. Compared to group rearing, isolated rearing led to better survival, shorter periods of development and stimulated growth. Due to different swimming behavior P. bernhardus zoeae needed larger water volumes than Carcinus maenas larvae. P. bernhardus zoeae were reared with best results when isolated in Petri dishes (ca. 50 ml). They fed on newly hatched brine shrimp nauplii ( Artemia spp.). P. bernhardus megalopa did not require any gastropod shell or substratum; it developed best in glass vials without any food. C. maenas larvae could be reared most sucessfully in glass vials (ca 20 ml) under a simulated day-night regime (LD 16:8); constant darkness had a detrimental effect on development, leading to prolonged stage-duration times. C. maenas larvae were fed a mixture of newly hatched brine shrimp naupli and rotifers ( Brachionus plicatilis).

  16. Effects of pesticides on DNA and protein of shrimp larvae Litopenaeus stylirostris of the California Gulf.

    Science.gov (United States)

    Galindo Reyes, J Guillermo; Leyva, Nancy R; Millan, Olivia A; Lazcano, Guadalupe A

    2002-10-01

    Recently, diverse pathologies and massive mortalities have been presented in shrimp hatcheries located along the California Gulf; therefore, toxic responses of shrimp larvae were used as biomarkers of pesticide pollution, because in this region intensive agriculture is practiced. Shrimp larvae were exposed to DDT, azinphosmethyl, permethrine, parathion, chlorpyrifos, malathion, endosulfan, and carbaryl, in order to determine LC50, DNA adducts and/or breaks, and total protein in larvae. The results indicate reductions in protein and DNA in larvae exposed to these pesticides, and in those exposed to DDT, breaks and/or adducts were registered. It is possible that pesticide pollution is a cause of these problems, because reduction in protein indicates a decrease in larvae growth rate and DNA breaks or adducts have been related to pathologies and carcinogenesis in many aquatic organisms.

  17. Marine Invertebrate Larvae Associated with Symbiodinium: A Mutualism from the Start?

    Directory of Open Access Journals (Sweden)

    Miguel Mies

    2017-05-01

    Full Text Available Symbiodinium are dinoflagellate photosynthetic algae that associate with a diverse array of marine invertebrates, and these relationships are comprehensively documented for adult animal hosts. Conversely, comparatively little is known about the associations during larval development of animal hosts, although four different metazoan phyla (Porifera, Cnidaria, Acoelomorpha, and Mollusca produce larvae associated with Symbiodinium. These phyla represent considerable diversities in larval forms, manner of symbiont acquisition, and requirements on the presence of symbionts for successful metamorphosis. Importantly, the different requirements are conveyed by specific symbiont types that are selected by the host animal larvae. Nevertheless, it remains to be determined whether these associations during larval stages already represent mutualistic interactions, as evident from the relationship of Symbiodinium with their adult animal hosts. For instance, molecular studies suggest that the host larval transcriptome is nearly unaltered after symbiont acquisition. Even so, a symbiosis-specific gene has been identified in Symbiodinium that is expressed in larval host stages, and similar genes are currently being described for host organisms. However, some reports suggest that the metabolic exchange between host larvae and Symbiodinium may not cover the energetic requirements of the host. Here, we review current studies to summarize what is known about the association between metazoan larvae and Symbiodinium. In particular, our aim was to gather in how far the mutualistic relationship present between adult animals hosts and Symbiodinium is already laid out at the time of symbiont acquisition by host larvae. We conclude that the mutualistic relationship between animal hosts and algal symbionts in many cases is not set up during larval development. Furthermore, symbiont identity may influence whether a mutualism can be established during host larval stages.

  18. Marine Invertebrate Larvae Associated with Symbiodinium: A Mutualism from the Start?

    KAUST Repository

    Mies, Miguel

    2017-05-30

    Symbiodinium are dinoflagellate photosynthetic algae that associate with a diverse array of marine invertebrates, and these relationships are comprehensively documented for adult animal hosts. Conversely, comparatively little is known about the associations during larval development of animal hosts, although four different metazoan phyla (Porifera, Cnidaria, Acoelomorpha, and Mollusca) produce larvae associated with Symbiodinium. These phyla represent considerable diversities in larval forms, manner of symbiont acquisition, and requirements on the presence of symbionts for successful metamorphosis. Importantly, the different requirements are conveyed by specific symbiont types that are selected by the host animal larvae. Nevertheless, it remains to be determined whether these associations during larval stages already represent mutualistic interactions, as evident from the relationship of Symbiodinium with their adult animal hosts. For instance, molecular studies suggest that the host larval transcriptome is nearly unaltered after symbiont acquisition. Even so, a symbiosis-specific gene has been identified in Symbiodinium that is expressed in larval host stages, and similar genes are currently being described for host organisms. However, some reports suggest that the metabolic exchange between host larvae and Symbiodinium may not cover the energetic requirements of the host. Here, we review current studies to summarize what is known about the association between metazoan larvae and Symbiodinium. In particular, our aim was to gather in how far the mutualistic relationship present between adult animals hosts and Symbiodinium is already laid out at the time of symbiont acquisition by host larvae. We conclude that the mutualistic relationship between animal hosts and algal symbionts in many cases is not set up during larval development. Furthermore, symbiont identity may influence whether a mutualism can be established during host larval stages.

  19. Locomotion and attachment of leaf beetle larvae Gastrophysa viridula (Coleoptera, Chrysomelidae).

    Science.gov (United States)

    Zurek, Daniel B; Gorb, Stanislav N; Voigt, Dagmar

    2015-02-06

    While adult green dock leaf beetles Gastrophysa viridula use tarsal adhesive setae to attach to and walk on smooth vertical surfaces and ceilings, larvae apply different devices for similar purposes: pretarsal adhesive pads on thoracic legs and a retractable pygopod at the 10th abdominal segment. Both are soft smooth structures and capable of wet adhesion. We studied attachment ability of different larval instars, considering the relationship between body weight and real contact area between attachment devices and the substrate. Larval gait patterns were analysed using high-speed video recordings. Instead of the tripod gait of adults, larvae walked by swinging contralateral legs simultaneously while adhering by the pygopod. Attachment ability of larval instars was measured by centrifugation on a spinning drum, revealing that attachment force decreases relative to weight. Contributions of different attachment devices to total attachment ability were investigated by selective disabling of organs by covering them with melted wax. Despite their smaller overall contact area, tarsal pads contributed to a larger extent to total attachment ability, probably because of their distributed spacing. Furthermore, we observed different behaviour in adults and larvae when centrifuged: while adults gradually slipped outward on the centrifuge drum surface, larvae stayed at the initial position until sudden detachment.

  20. Detrimental effects of geldanamycin on adults and larvae of Trichinella spiralis

    Directory of Open Access Journals (Sweden)

    Othman A. A.

    2016-06-01

    Full Text Available Trichinellosis is a zoonotic disease affecting mainly the temperate regions. The treatment is a challenge for the physician, and the available therapy is far from ideal. Therefore, this work aimed to evaluate the effect of heat shock protein 90 inhibitor, geldanamycin, on the adult worms and larvae of Trichinella spiralis. This research comprised an in vivo study in which T. spiralis-infected mice were treated by two different doses of geldanamycin, thereafter larval count and pathological changes were determined in the muscles. Meanwhile, the in vitro study investigated the effect of two different concentrations of geldanamycin on adult worms and larvae of T. spiralis via transmission electron microscopy. The in vivo study showed significant reduction of muscle larval counts under the effect of geldanamycin. Moreover, characteristic changes were noted as regards the parasite and the inflammatory response. The in vitro study revealed degenerative changes in the body wall of larvae and adults of T. spiralis under the influence of geldanamycin. In conclusion, heat shock protein 90 inhibitor, geldanamycin, seems to have detrimental effects on the adults and larvae of T. spiralis. It, or one of its derivatives, could be an adjuvant to anthelmintic therapy of trichinellosis, but more studies are warranted to establish its usefulness.

  1. Development of Tribolium castaneum (Herbst) larvae after gamma irradiation of eggs

    International Nuclear Information System (INIS)

    Mehta, V.K.; Sethi, G.R.; Garg, A.K.

    1990-01-01

    Development of Rust-red flour beetle, Tribolium castaneum larvae, after gamma irradiation of eggs of two different age groups was studied. Results indicated that, if 2 to 3 day old eggs were irradiated with 6 Krad, the development of larvae emerging from such eggs is completely arrested at the end of 18 days after hatching. In case of comparatively older eggs (3 to 4 day old), 8 Krad dose of gamma radiation was required to produce the similar results. However, treatment with 10 Krad resulted in 100 per cent egg mortality in both the age groups. The studies thus reveal that survival of the larvae depends not only on the radiation dose and the time period elapsed after irradiation but also on the age of eggs at the time of exposure. (author). 9 refs., 1 tab

  2. Rate of sediment intake by midge larvae (Chironomus plumosus: diptera) using a 134Cs tracer

    International Nuclear Information System (INIS)

    Gerking, S.D.; Berg, A.; Gerard, P.

    1976-01-01

    The food intake and assimilation of midge larvae (Chironomus plumosus) were determined by a 134 Cs technique which utilized the principle that the rate of excretion can be substituted for the rate of absorption when the larvae are in 134 Cs equilibrium with their environment. The larvae were introduced into contaminated sediments until they reached 134 Cs equilibrium. The time of reaching equilibrium and levels of radioactivity were the same at 10 and at 15 0 C (70 hr at a level of 1367 dpm/mg of larva) and were both significantly different from that at 20 0 C (40 hr at 1062 dpm/mg of larva). Cesium-134 elimination was followed on equilibrated larvae for as long as 330 hr. One egestion compartment (fast) and two excretion (medium and slow) compartments could be recognized at the three experimental temperatures. The loss rates from the second and third compartments at 10 0 C were slower and stretched out over longer time periods compared with those at 15 0 C, while the loss rate from the first compartment was much more comparable at the two temperatures. The first and second compartments merged at 20 0 C, while the slow compartment rose to almost three times that at 15 0 C. The food intake was nearly the same at the three temperatures (0.0986, 0.0893 and 0.0876 mg dry sediment/mg of larva/day). Thus, the larvae relied on an increase in assimilation to meet increased metabolic requirements at higher temperatures rather than depending upon a higher food intake. The gross growth efficiencies varied with temperature from 9.9 percent at 10 0 C to 15.1 percent at 15 0 C

  3. Modeling peripheral olfactory coding in Drosophila larvae.

    Directory of Open Access Journals (Sweden)

    Derek J Hoare

    Full Text Available The Drosophila larva possesses just 21 unique and identifiable pairs of olfactory sensory neurons (OSNs, enabling investigation of the contribution of individual OSN classes to the peripheral olfactory code. We combined electrophysiological and computational modeling to explore the nature of the peripheral olfactory code in situ. We recorded firing responses of 19/21 OSNs to a panel of 19 odors. This was achieved by creating larvae expressing just one functioning class of odorant receptor, and hence OSN. Odor response profiles of each OSN class were highly specific and unique. However many OSN-odor pairs yielded variable responses, some of which were statistically indistinguishable from background activity. We used these electrophysiological data, incorporating both responses and spontaneous firing activity, to develop a bayesian decoding model of olfactory processing. The model was able to accurately predict odor identity from raw OSN responses; prediction accuracy ranged from 12%-77% (mean for all odors 45.2% but was always significantly above chance (5.6%. However, there was no correlation between prediction accuracy for a given odor and the strength of responses of wild-type larvae to the same odor in a behavioral assay. We also used the model to predict the ability of the code to discriminate between pairs of odors. Some of these predictions were supported in a behavioral discrimination (masking assay but others were not. We conclude that our model of the peripheral code represents basic features of odor detection and discrimination, yielding insights into the information available to higher processing structures in the brain.

  4. Influence of larval period on responses of overwintering green frog (Rana clamitans) larvae exposed to contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Snodgrass, J.W.; Hopkins, W.A.; Jackson, B.P.; Baionno, J.A.; Broughton, J. [Towson State University, Towson, MD (US). Dept. of Biological Science

    2005-06-01

    Pond-breeding amphibians exhibit large intra- and interspecific differences in the duration of the aquatic larval phase. In contaminated aquatic environments, a prolonged larval phase means prolonged exposure to pollutants and, potentially, more severe toxic effects. In the laboratory, we tested this hypothesis by exposing green frog larvae (Rana clamitans) to commercial clean sand (control), sediment from an abandoned surface mine (mine), or sediment contaminated with coal combustion waste (CCW). By collecting eggs late in the breeding season, we obligated larvae to overwinter and spend a protracted amount of time exposed to contaminated sediments. The experiment was continued until all larvae either successfully completed metamorphosis or died (301 d). Larvae exposed to mine sediments accumulated significant levels of Pb and Zn, whereas larvae exposed to CCW-contaminated sediment accumulated significant levels of As, Se, Sr, and V. Larvae exposed to mine sediments suffered sublethal effects in the form of reduced growth and size at metamorphosis, but the proportion of larvae successfully completing metamorphosis (93%) was the same for both control and mine treatments. In contrast, larvae exposed to CCW-contaminated sediment suffered greatly reduced survival (13%) compared to both control and mine treatments. Moreover, among larvae in the CCW treatment, the majority of mortality occurred during the latter part the overwintering period (after day 205), corresponding to the onset of metamorphosis in the controls. Our results suggest that the length of the larval period may be one of many life-history or ecological characteristics that influence the sensitivity of aquatic breeding amphibians to environmental pollutants.

  5. Ultrastructural observations of the larva of Tubiluchus corallicola (Priapulida)

    Science.gov (United States)

    Higgins, R. P.; Storch, V.

    1989-03-01

    Larvae of Tubiluchus corallicola van der Land 1968 were investigated by scanning and transmission electron microscopy. The scalids are sensory organs, each has a bipolar receptor cell with a single apical cilium similar to the scalid in the adult. Muscle cells of the larva are more differentiated than previously reported for other Priapulida; the larval arrangement of circular and longitudinal musculature differs from that of the adult, and a diaphragm is reported for the first time in Priapulida. The diaphragm may function in hydrostatic control of eversion and inversion of the introvert and mouth cone. The functional morphology of these two structures is discussed and contrasted with the Kinorhyncha.

  6. Chemical composition and fatty acid profile of edible larva of Cirina ...

    African Journals Online (AJOL)

    The nutrient composition of the larva of Cirina forda (Westwood) was determined. It contained 33.12 (0.87 g/100g crude protein, 9.40 (0.16 g/100g crude fibre, 12.24 (18 g/ 100g fat, 7.12 ( 0.32 gl 100g ash, 38.12 (0.65 g/ 100g carbohydrate and gross energy value of 359 (2.83 Kcal/ 100g. The larva is an excellent source of ...

  7. External morphology of the two cypridiform ascothoracid-larva instars of Dendrogaster: The evolutionary significance of the two-step metamorphosis and comparison of lattice organs between larvae and adult males (Crustacea, Thecostraca, Ascothoracida)

    DEFF Research Database (Denmark)

    Kolbasov, G.A.; Grygier, M.J.; Høeg, Jens Thorvald

    2008-01-01

    We describe the external morphology of the two cypridiform larval instars (first and second ascothoracid-larvae, or -a-cyprids") of the ascothoracidan genus Dendrogaster. Ascothoracid-larvae of five species were studied with light and scanning electron microscopy, including both ascothoracid-larv...

  8. Molecular identification of nematode larvae different from those of the Trichinella genus detected by muscle digestion.

    Science.gov (United States)

    Marucci, Gianluca; Interisano, Maria; La Rosa, Giuseppe; Pozio, Edoardo

    2013-05-20

    Although larvae of the genus Trichinella are the most common parasite species detected in vertebrate muscles using artificial digestion, nematode larvae belonging to other genera are sometimes detected and incorrectly identified as Trichinella. However, it is often very difficult to identify these larvae at the species, genus or family level using microscopy because of the absence of specific morphological characters or cuticle damage, and the only means of identification is PCR and sequencing of specific molecular markers (12S mtDNA; COI; 18S rDNA; and ITS1). From 2008 to 2011, 18 nematode isolates not belonging to the genus Trichinella were collected from different host species. Eleven of these isolates were successfully identified at the species, genus or superfamily level: larvae from two common kestrels, three hooded crows, a hen harrier and a domestic pig were identified as Toxocara cati; larvae from a badger were identified as Toxocara canis; larvae from a domestic pig were identified as a free-living nematode of the genus Panagrolaimus; larvae from a wild boar were identified as belonging to the Metastrongylus genus; and larvae from a rough-legged buzzard were identified as belonging to the superfamily Filarioidea. The recovery of nematodes belonging to genera other than Trichinella during routine meat inspection suggests that the persons performing the analyses need to be informed of the possibility of false positives and that a molecular-based identification system that allows for a rapid and reliable response must be adopted (i.e., a DNA barcoding-like system). Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Effects of kinship or familiarity? Small thrips larvae experience lower predation risk only in groups of mixed-size siblings

    NARCIS (Netherlands)

    de Bruijn, P.J.A.; Sabelis, M.W.; Egas, M.

    2014-01-01

    In many species of insects, larvae are distributed in an aggregated fashion. As they may differ in size and size matters to predation risk, small larvae may be less likely to fall prey to predators when near large and therefore better-defended larvae. We hypothesize that the small larvae may profit

  10. Nutritional Transition Period in Early Larvae Clarias Gariepinus

    International Nuclear Information System (INIS)

    Ing, N.S.; Chew, H.H.

    2015-01-01

    The nutritional transition period of Clarias gariepinus were described based on the early development from hatching to 120 hours after hatching (hAH) reared at 27.5 - 28.6 degree Celsius. Newly hatched larvae had a large greenish yolk sac volume (0.99 ± 0.31 mm"3) located below a straight undeveloped digestive tract, mouth not opened, eyes unpigmented and the larvae lie on the bottom of rearing tank. During endogenous feeding period, the larval feeding system has developed rapidly with development oesophagus. Yolk sac were not completely depleted at the onset of exogenous feeding (36 hAH, 0.19 ± 0.11 mm"3), and a period of mixed nutrition was observed up to 68 hAH when yolk was completely exhausted. Yolk sac volume was significantly different by time at hatching, 6, 12 and 18 to 36 hAH (ANOVA, P<0.05). At 36 hAH, the larvae commenced feeding once morphologically developed with opened anus, functional jaw and intestine, and demonstrated horizontally swimming. The rudimentary chemoreceptors like olfactory organs and taste buds that were found on the barbels and oral cavity assisted in food detection and commenced feeding without vision. Due to the cannibalistic behaviour at early stage, feed are suggested to be provided during 36 hAH and avoided delay feeding in the larval rearing. (author)

  11. Infection of silkworm larvae by the entomopathogenic fungus Metarhizium anisopliae

    Directory of Open Access Journals (Sweden)

    Lucineia de Fátima Chasko Ribeiro

    Full Text Available ABSTRACT: The isolate E9 of Metarhizium anisopliae was used in commercial hybrids of Bombyx mori larvae to evaluate its biological effect. Symptomatological analyses showed typical signs of fungal infection. Histopathology revealed the presence of large numbers of hemocytes in the hemocoel, and on the sixth dpi the bodies of the insects appeared to be colonised by the fungus. The isolate E9 is pathogenic to larvae B. mori and; therefore, death of the insects was caused by the colonization of fungus in the epidermal and mesodermal tissues.

  12. Effects of algal diets and starvation on growth, survival and fatty acid composition of Solen marginatus (Bivalvia: Solenidae larvae

    Directory of Open Access Journals (Sweden)

    Fiz Da Costa

    2012-08-01

    Full Text Available The aim of this study was to investigate whether it is necessary to feed Solen marginatus (Pennánt, 1777 larvae externally and the evolution of fatty acids in the neutral and polar lipids during larval development in starved larvae and larvae fed on two different microalgal diets. Larvae were subjected to three different treatments: 1. 10 equivalent cells (Isochrysis galbana, Pavlova lutheri and Chaetoceros calcitrans plus 20 equivalent cells of Tetraselmis suecica; 2. 80 equivalent cells of I. galbana and 3. starvation during eight days, and then individuals were re-fed on diet 1. The best results for growth were observed in larvae fed on diet 1. Starved larvae reached the best survival rate at day 8 (66%. However, three days after re-feeding all larvae died, suggesting that the “point of no return” was exceeded. In spite of the large size of S. marginatus eggs and the great amount of stored reserves, the larvae need to feed on microalgae to undergo metamorphosis. Non-methyle-interrupted dienoic fatty acids and their precursors 16:1n-7 and 18:1n-9 are of great importance in starved larvae. Saturated fatty acids, especially 16:0, fuel larval development. A certain degree of bioconversion of 18:2n-6 to 20:4n-6 was observed in S. marginatus larvae.

  13. Efficacy of photodynamic therapy against larvae of Aedes aegypti: confocal microscopy and fluorescence-lifetime imaging

    Science.gov (United States)

    de Souza, L. M.; Pratavieira, S.; Inada, N. M.; Kurachi, C.; Corbi, J.; Guimarães, F. E. G.; Bagnato, V. S.

    2014-03-01

    Recently a few demonstration on the use of Photodynamic Reaction as possibility to eliminate larvae that transmit diseases for men has been successfully demonstrated. This promising tool cannot be vastly used due to many problems, including the lake of investigation concerning the mechanisms of larvae killing as well as security concerning the use of photosensitizers in open environment. In this study, we investigate some of the mechanisms in which porphyrin (Photogem) is incorporated on the Aedes aegypti larvae previously to illumination and killing. Larvae at second instar were exposed to the photosensitizer and after 30 minutes imaged by a confocal fluorescence microscope. It was observed the presence of photosensitizer in the gut and at the digestive tract of the larva. Fluorescence-Lifetime Imaging showed greater photosensitizer concentration in the intestinal wall of the samples, which produces a strong decrease of the Photogem fluorescence lifetime. For Photodynamic Therapy exposition to different light doses and concentrations of porphyrin were employed. Three different light sources (LED, Fluorescent lamp, Sun light) also were tested. Sun light and fluorescent lamp shows close to 100% of mortality after 24 hrs. of illumination. These results indicate the potential use of photodynamic effect against the LARVAE of Aedes aegypti.

  14. Effects of gamma radiation on respiration of larvae of Pieris brassicae L

    International Nuclear Information System (INIS)

    Miah, M.A.H.

    1979-01-01

    The oxygen consumption and respiratory quotient of larvae of Pieris brassicae, the cabbage white butterfly were studied following treatment with 6, 9 and 12 krad of gamma radiation from a 60 Co source. The dose rate was 1.229 krad/min. Oxygen consumption and R.Q. were measured at 25 0 C with a Warburg respirometer. There was no difference in oxygen consumption and R.Q. between larvae of each sex though the rate of oxygen consumption with body weight increased in females and decreased in males. Irradiation did not produce any noticeable change in oxygen consumption of larvae. But the R.Q.'s in the treated individuals were higher than in the untreated ones indicating greater use of carbohydrates. (author)

  15. Toxocara cati larva migrans in domestic pigs - detected at slaughterhouse control in Norway

    Directory of Open Access Journals (Sweden)

    Davidson Rebecca K

    2012-11-01

    Full Text Available Abstract Routine Trichinella meat inspection at the slaughterhouse detected one larva in a pooled batch of 100 pig samples. The larva was sent to the Norwegian Veterinary Institute (NVI for species identification. Morphological examination revealed that the larva was not Trichinella spp. Molecular analysis was performed. PCR and sequencing of 5S/ITS identified the larva as Toxocara cati. A second round of digests was carried out at the meat inspection laboratory, in smaller batches to try to identify the infected animal. No further larvae were detected and it was not possible to identify which of the 100 animals the larva had come from. This is the first time that Toxocara cati has been reported in slaughterhouse pigs in Norway. Although the infected individual could not be identified, the meat originated from one of six potential farms. A small survey regarding rodent control and cats was sent to each of these farms. Cats had restricted access to food storage areas (two farms reported that cats had access whilst none of the farms allowed cats into the production housing. Cats were, however, present on all the farms (mostly stray cats of unknown health status. Half of the farms also reported seeing rodents in the pig housing during the previous six months and half reported finding rodents in the feed and straw storage areas. We were unable to narrow down the source of infection – however contamination of food or bedding material, with cat faeces or infected rodents, in addition to the presence of infected rodents in pig housing remain potential routes of infection.

  16. Body size, swimming speed, or thermal sensitivity? Predator-imposed selection on amphibian larvae.

    Science.gov (United States)

    Gvoždík, Lumír; Smolinský, Radovan

    2015-11-02

    Many animals rely on their escape performance during predator encounters. Because of its dependence on body size and temperature, escape velocity is fully characterized by three measures, absolute value, size-corrected value, and its response to temperature (thermal sensitivity). The primary target of the selection imposed by predators is poorly understood. We examined predator (dragonfly larva)-imposed selection on prey (newt larvae) body size and characteristics of escape velocity using replicated and controlled predation experiments under seminatural conditions. Specifically, because these species experience a wide range of temperatures throughout their larval phases, we predict that larvae achieving high swimming velocities across temperatures will have a selective advantage over more thermally sensitive individuals. Nonzero selection differentials indicated that predators selected for prey body size and both absolute and size-corrected maximum swimming velocity. Comparison of selection differentials with control confirmed selection only on body size, i.e., dragonfly larvae preferably preyed on small newt larvae. Maximum swimming velocity and its thermal sensitivity showed low group repeatability, which contributed to non-detectable selection on both characteristics of escape performance. In the newt-dragonfly larvae interaction, body size plays a more important role than maximum values and thermal sensitivity of swimming velocity during predator escape. This corroborates the general importance of body size in predator-prey interactions. The absence of an appropriate control in predation experiments may lead to potentially misleading conclusions about the primary target of predator-imposed selection. Insights from predation experiments contribute to our understanding of the link between performance and fitness, and further improve mechanistic models of predator-prey interactions and food web dynamics.

  17. Temperature-dependent settlement of planula larvae of two scyphozoan jellyfish from the North Sea

    Science.gov (United States)

    Gambill, Maria; McNaughton, Sadie L.; Kreus, Markus; Peck, Myron A.

    2018-02-01

    Exploring the settlement dynamics of the planula larvae is critical to understanding the establishment of polyp populations that can give rise to blooms of scyphozoan jellyfish. We conducted experiments to examine the effects of temperature on settlement of planulae of the scyphozoans Cyanea lamarckii and Chrysaora hysoscella, two jellyfish commonly encountered within the North Sea. When provided immediate access to substrate, larvae of C. lamarckii were able to settle at each of 12 temperatures between 9 and 27 °C. Most settlement occurred within the first five days and warmer temperatures were not only associated with decreased time to settlement but also increased settlement success. When not allowed access to substrate and maintained in the water column, planula larvae remained competent to settle for 21, 21 and 14 days at 11.3, 13.4 and 19.4 °C, respectively. Based on these maximum times of competency, hydrodynamic model simulations suggested that the planula larvae of C. lamarckii released in May could be transported up to 100 km before settlement. A substrate choice experiment indicated that larvae of C. hysoscella settled in similar numbers onto PET, wood and concrete. Settlement was highest at 20 °C and a 12/12 light/dark regime and lower at 10 °C and 15 °C in total darkness. The results of all three experiments suggest that projected warming of the North Sea will not impede the settlement of planula larvae of resident C. lamarckii and C. hysoscella populations. Species- and/or population-specific differences may exist in the ecophysiology of planula larvae and additional experiments are needed to understand the mechanisms promoting the establishment of new benthic populations of polyps. That information, combined with process knowledge on the productivity of benthic polyps, will be needed to better understand and predict climate-dependent changes in the production of scyphozoans and other gelatinous plankton.

  18. Energy density of zooplankton and fish larvae in the southern Catalan Sea (NW Mediterranean)

    Science.gov (United States)

    Barroeta, Ziortza; Olivar, M. Pilar; Palomera, Isabel

    2017-06-01

    In marine communities, energy of small planktonic organisms is transferred to their predators through feeding. The energy accumulated as organic substances by the different plankton organisms (Energetic Density content, ED) has been analysed in high latitudes and tropical areas, but not in the Mediterranean Sea. In this study, we approach this type of investigation for Mediterranean plankton through measures of total calorimetric content using an oxygen bomb calorimeter. We examined the spatiotemporal variation in the ED of microplankton (50-200 μm) and mesozooplankton (200-2000 μm), and two plankton-consumers, sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) larvae. The study was carried out during the winter and summer of 2013 off the Ebro River Delta (NW Mediterranean Sea). Both plankton fractions showed a more coastal distribution and higher biomasses during winter, the period of sardine larvae occurrences, in front of a wider cross-shelf distribution and lower biomasses in summer, when anchovy appeared. ED values increased with the size of each plankton component, i.e., microzooplankton < mesozooplankton < fish larvae. A tendency for higher plankton ED in the winter period was observed, although being only significant for coastal zone, associated to the more productive waters there. Sardine and anchovy larvae showed an increasing trend in the amount of energy during development, with significantly lower ED between early larvae (6-10 mm standard length) and late postflexion stages (16-20 mm standard length). Small larvae of both species departed from a similarly low ED content, but in the next two size classes sardine larvae showed higher ED values than anchovy, being significantly higher in the 16-20 mm size class. Information on larval feeding patterns and larval growth rates for each species were used to discuss differences in energy allocation strategies.

  19. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Directory of Open Access Journals (Sweden)

    George G Waldbusser

    Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

  20. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Science.gov (United States)

    Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

    2015-01-01

    Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

  1. Susceptibilidade de larvas de Cerotoma arcuata Olivier (Coleoptera: Chrysomelidae a Beauveria bassiana (Bals. Vuillemin, Metarhizium anisopliae (Metsch. Sorokin e Bacillus thuringiensis Berliner Susceptibility of Cerotoma arcuata Olivier (Coleoptera: Chrysomelidae larvae to Beauveria bassiana (Bals. Vuillemin, Metarhizium anisopliae (Metsch. Sorokin and Bacillus thuringiensis Berliner

    Directory of Open Access Journals (Sweden)

    Maria Lucia França Teixeira

    2007-02-01

    Full Text Available Larvas de 2° instar de Cerotoma arcuata foram avaliadas em relação à susceptibilidade aos fungos entomopatogênicos Beauveria bassiana, Metarhizium anisopliae e a bactéria Bacillus thuringiensis com as toxinas Cry3. Os insetos adultos foram mantidos em gaiolas e alimentados com plântulas de feijão (Phaseolus vulgaris L. e as larvas em "gerbox" com cotilédones de plântulas de feijão recém-germinadas. Das oito estirpes de B. bassiana avaliadas, CG 156 e CG 213 causaram 100% de mortalidade das larvas, as duas estirpes de M. anisopliae CG 210 e CG 321 foram patogênicas, eliminando 80 e 100% das larvas de C. arcuata, e, das cinco estirpes de B. thuringiensis testadas, o isolado CG 940 causou 70% de mortalidade das larvas.Second instar larvae of Cerotoma arcuata were evaluated concerning the susceptibility to fungi Beauveria bassiana and Metarhizium anisopliae and Bacillus thuringiensis strains containing Cry3 toxin. Adults of C. arcuata were kept in large cages and fed on bean seedlings and the larvae were reared in ‘gearbox’ feeding on germinated Phaseolus bean cotyledons. Strains CG 156 and CG 213 of B. bassiana killed 100% of the insect larvae and strains CG 210 and CG 321 of M. anisopliae killed 80 and 100% of the insect larvae. Strain CG 940 of B. thuringiensis killed 70% of the insect larvae.

  2. Reduction of Escherichia coli, Salmonella Enteritidis and Campylobacter jejuni in poultry manure by rearing of Musca domestica fly larvae

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Fischer, C.; Bjerrum, L.

    2017-01-01

    A major barrier for using animal waste as substrate for production of insects for feed or food is the concern for safety of the end products. In this study we investigated how rearing of fly larvae of Musca domestica in poultry manure influenced the counts of three pathogenic test strains...... of the larvae stage. This study provides data for evaluation of feed safety of fly larvae reared on animal waste. Furthermore suggests a potential use for reduction of these pathogens in manure........ Enteritidis, and C. jejuni was faster in manure with rearing of fly larvae than in manure without larvae; an 8 log10 reduction of all three test bacteria was observed within four days in manure with larvae; compared to manure without larvae where a 1 to 2 log10 was observed. We found no sign of propagation...

  3. Dynamic of decapod crustacean larvae on the entrance of Guanabara bay

    Directory of Open Access Journals (Sweden)

    Lohengrin Dias de Almeida Fernandes

    2002-12-01

    Full Text Available In the present study, we observed seasonal variations in the density of decapod larvae as well as changes in density related to diurnal and tidal cycles. Among the decapod larvae collected, portunids and grapsids were the most abundant, especially during nocturnal ebb tides and near the surface. The same results were obtained in late winter (September and late summer (March. These results demonstrated a flow of decapod larvae from Guanabara Bay to adjacent coastal waters. Luciferid (Lucifer faxoni was the only group with high densities during flood tides and we suggest this is an evidence of L. faxoni larvae entering Guanabara Bay in late winter. Probably these changes in distribution of Lucifer faxoni among winter and summer were related to reproductive cycle in the bay. For the portunids, grapsids and ocypodids, a similar dispersion strategy was observed towards adjacent coastal waters in the surface during nocturnal ebb tides.Larvas de crustáceos decápodes são organismos planctônicos comuns tanto em regiões costeiras rasas como em estuários. Nesse trabalho, foi acompanhada a variação da densidade das larvas de decápodes num ponto estratégico entre a porção interior da baía de Guanabara e a região costeira adjacente. A coleta de grandes quantidades de zoés de braquiúros, principalmente das famílias Portunidae e Grapsidae, na superfície durante as marés de vazante noturnas sugere uma tendência de exportação para a região costeira adjacente. A repetição desse padrão no inverno e no verão demonstrou que as respostas dos organismos às variações de luz e maré não foram alteradas de modo significativo entre as duas estações do ano, exceto para os luciferídeos. O fluxo observado para a única espécie de luciferídeo capturada (Lucifer faxoni foi significativamente diferente entre os dois períodos do ano analisados. É provável que essas diferenças na distribuição de Lucifer faxoni seja relacionada ao ciclo

  4. Development of Metarhizium anisopliae and Beauveria bassiana formulations for control of malaria mosquito larvae

    NARCIS (Netherlands)

    Bukhari, S.T.; Takken, W.; Koenraadt, C.J.M.

    2011-01-01

    Background The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana have demonstrated effectiveness against anopheline larvae in the laboratory. However, utilising these fungi for the control of anopheline larvae under field conditions, relies on development of effective means of

  5. High mortality of the larvae of the common mussel at low concentrations of tributyltin

    Energy Technology Data Exchange (ETDEWEB)

    Beaumont, A.R.; Budd, M.D.

    1984-11-01

    Laboratory reared veliger larvae of the common mussel Mytilus edulis were grown for 15 days in filtered seawater containing 10 ..mu..g l/sup -1/, 1 ..mu..g l/sup -1/ and 0.1 ..mu..g l/sup -1/ tributyltin oxide, (TBTO), the biocide in recent antifouling paint formulations. No larvae survived longer than 5 days in 10 ..mu..g l/sup -1/ TBTO. Approximately half the larvae subjected to 0.1 ..mu..g/sup -1/ TBTO were dead by day 15 (approximately 15 day LC/sub 50/ = 0.1 ..sqrt..g l/sup -1/ TBTO) and most of the surviving larvae were moribund and had grown significantly more slowly than controls. It is noted that current recorded levels of TBT at several UK estuarine sites are higher than 0.1 ..mu..g l/sup -1/ and there has therefore probably been a high mortality of mussel larvae at such sites. The results are discussed in relation to the reported short-term toxicity of organotins to other marine organisms and the value of carrying out longer term tests at low levels of TBT is pointed out.

  6. In vitro effects of household products on Calliphoridae larvae development: implication for forensic entomology.

    Science.gov (United States)

    Aubernon, Cindy; Devigne, Cedric; Hedouin, Valery; Gosset, Didier; Charabidze, Damien

    2015-01-01

    Several parameters can delay the first arrival of flies on a corpse and the subsequent development of the larvae. This study focuses on the development of Lucilia sericata (Diptera: Calliphoridae) (Meigen, 1826) on household chemical-contaminated substrates. bleach, perfume, hydrochloric acid, caustic soda, insecticide, mosquito repellent, and gasoline in quantities consistent with an amount that could possibly be spilled on a corpse were mixed with beef liver to simulate contaminated fleshes. Larvae were bred at 25 °C on these media until emergence. Four developmental parameters were followed: survival rates, development times, sex ratios, and adult sizes. Hydrochloric acid, insecticide, and gasoline killed all larvae. In low quantities, caustic soda and mosquito repellent increased the development time and decreased the adult size. However, high quantities of these chemicals killed all larvae. Lastly, bleach and perfume did not affect the survival rate and barely impacted the development time or adult size. These results demonstrate common household products spilled on a corpse can strongly affect the development of Calliphoridae larvae. The effects of such products should be considered in forensic entomology cases. © 2014 American Academy of Forensic Sciences.

  7. A novel mode of induction of the humoral innate immune response in Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kenmoku

    2017-03-01

    Full Text Available Drosophila adults have been utilized as a genetically tractable model organism to decipher the molecular mechanisms of humoral innate immune responses. In an effort to promote the utility of Drosophila larvae as an additional model system, in this study, we describe a novel aspect of an induction mechanism for innate immunity in these larvae. By using a fine tungsten needle created for manipulating semi-conductor devices, larvae were subjected to septic injury. However, although Toll pathway mutants were susceptible to infection with Gram-positive bacteria as had been shown for Drosophila adults, microbe clearance was not affected in the mutants. In addition, Drosophila larvae were found to be sensitive to mechanical stimuli with respect to the activation of a sterile humoral response. In particular, pinching with forceps to a degree that might cause minor damage to larval tissues could induce the expression of the antifungal peptide gene Drosomycin; notably, this induction was partially independent of the Toll and immune deficiency pathways. We therefore propose that Drosophila larvae might serve as a useful model to analyze the infectious and non-infectious inflammation that underlies various inflammatory diseases such as ischemia, atherosclerosis and cancer.

  8. The effect of 210Pb and stable lead on the induction of mouthpart deformities in chironomid larvae

    International Nuclear Information System (INIS)

    Bird, G.A.; Schwartz, W.J.; Hoffman, D.

    1995-07-01

    To determine whether mouthpart deformities in chironomid larvae from Port Hope Harbour, Ontario, are the result of exposure to ionizing radiation or heavy metals in the sediment, Chironomus tentans larvae were exposed in the laboratory to concentrations of 210 Pb and stable lead representative of contaminant levels in the harbour. Exposure to 100, 1000, and 2000 Bq 210 Pb·g -1 dry sediment had no effect on the survival, growth of the larvae or frequency of deformities. Likewise, exposure to 0.5 and 5.0 mg lead·g -1 dry sediment had no effect on the larvae, but exposure to 35.0 mg lead·g -1 dry sediment resulted in 100% mortality of the larvae. These results indicate that the observed mouthpart deformities in chironomid larvae in Port Hope Harbour are not the result of radiation exposure. They also indicate that heavy metals (lead) may be having an impact on the population. (author). 28 refs., 9 tabs., 4 figs

  9. Elementary budget of stag beetle larvae associated with selective utilization of nitrogen in decaying wood

    Science.gov (United States)

    Tanahashi, Masahiko; Ikeda, Hiroshi; Kubota, Kôhei

    2018-06-01

    Wood degradation by insects plays important roles for the forest matter cycling. Since wood is deficient in nitrogen compared to the insect body, wood-feeding insects need to assimilate the nitrogen selectively and discard an excess carbon. Such a stoichiometric imbalance between food and body will cause high metabolic cost; therefore, wood-feeding insects may somehow alleviate the stoichiometric imbalance. Here, we investigated the carbon and nitrogen budgets of the larvae of stag beetle, Dorcus rectus, which feed on decaying wood. Assimilation efficiency of ingested wood was 22%, and those values based on the carbon and nitrogen were 27 and 45%, respectively, suggesting the selective digestion of nitrogen in wood. Element-based gross growth efficiency was much higher for nitrogen (45%) than for carbon (3%). As a result, the larvae released 24% of the ingested carbon as volatile, whereas almost no gaseous exchange was observed for nitrogen. Moreover, solubility-based elementary analysis revealed that the larvae mainly utilized alkaline-soluble-water-insoluble fraction of wood, which is rich in nitrogen. Actually, the midgut of the larvae was highly alkaline (pH 10.3). Stag beetle larvae are known to exhibit coprophagy, and here we also confirmed that alkaline-soluble-water-insoluble nitrogen increased again from fresh feces to old feces in the field. Stable isotope analysis suggested the utilization of aerial nitrogen by larvae; however, its actual contribution is still disputable. Those results suggest that D. rectus larvae selectively utilize alkaline-soluble nitrogenous substrates by using their highly alkaline midgut, and perhaps associate with microbes that enhance the nitrogen recycling in feces.

  10. Elementary budget of stag beetle larvae associated with selective utilization of nitrogen in decaying wood.

    Science.gov (United States)

    Tanahashi, Masahiko; Ikeda, Hiroshi; Kubota, Kôhei

    2018-05-03

    Wood degradation by insects plays important roles for the forest matter cycling. Since wood is deficient in nitrogen compared to the insect body, wood-feeding insects need to assimilate the nitrogen selectively and discard an excess carbon. Such a stoichiometric imbalance between food and body will cause high metabolic cost; therefore, wood-feeding insects may somehow alleviate the stoichiometric imbalance. Here, we investigated the carbon and nitrogen budgets of the larvae of stag beetle, Dorcus rectus, which feed on decaying wood. Assimilation efficiency of ingested wood was 22%, and those values based on the carbon and nitrogen were 27 and 45%, respectively, suggesting the selective digestion of nitrogen in wood. Element-based gross growth efficiency was much higher for nitrogen (45%) than for carbon (3%). As a result, the larvae released 24% of the ingested carbon as volatile, whereas almost no gaseous exchange was observed for nitrogen. Moreover, solubility-based elementary analysis revealed that the larvae mainly utilized alkaline-soluble-water-insoluble fraction of wood, which is rich in nitrogen. Actually, the midgut of the larvae was highly alkaline (pH 10.3). Stag beetle larvae are known to exhibit coprophagy, and here we also confirmed that alkaline-soluble-water-insoluble nitrogen increased again from fresh feces to old feces in the field. Stable isotope analysis suggested the utilization of aerial nitrogen by larvae; however, its actual contribution is still disputable. Those results suggest that D. rectus larvae selectively utilize alkaline-soluble nitrogenous substrates by using their highly alkaline midgut, and perhaps associate with microbes that enhance the nitrogen recycling in feces.

  11. A new procedure for marinating fresh anchovies and ensuring the rapid destruction of Anisakis larvae.

    Science.gov (United States)

    Sánchez-Monsalvez, I; de Armas-Serra, C; Martínez, J; Dorado, M; Sánchez, A; Rodríguez-Caabeiro, F

    2005-05-01

    The consumption of marinated anchovies is the main route of transmission of anisakiasis in Spain. Because this country is one of the world's major tourist destinations, this traditional food also poses a potential health risk to millions of foreign visitors. Anisakis larvae are not destroyed by the traditional marinating procedure, and alternative methods, such as long-term storage in brine, freezing, or hydrostatic pressure treatment, all present major difficulties. In this study, we used high food-grade acetic acid concentrations (10, 20, 30, and 40% [vol/vol] in line with the quantum satis rule) to destroy these larvae rapidly, and we report data on the survival of Anisakis larvae exposed directly to different marinades and when the larvae are placed under the fish musculature. The percentage of salt and acetic acid in the fish tissue water phase was also determined. A marinating procedure is proposed that ensures the rapid death of Anisakis through the use of strong acetic acid concentrations. Posttreatment washes with water reduce these to levels acceptable to consumers. The sensory characteristics of the product were shown to be satisfactory. The actual selection of an acetic acid concentration for marinating depends on costs and the processing time available. The physiological stress of the larvae exposed to the different marinades was determined by measuring the levels of their stress proteins. The latter are good indicators of injury and might reflect the infectivity of larvae. In addition, we also used a rat model to determine the infectivity of larvae considered microscopically dead.

  12. Patogenicidade de isolados de Beauveria bassiana para ovos, larvas e ninfas ingurgitadas de Rhipicephalus sanguineus Pathogenicity of Beauveria bassiana isolates towards eggs, larvae and engorged nymphs of Rhipicephalus sanguineus

    Directory of Open Access Journals (Sweden)

    Nancy Prette

    2005-08-01

    Full Text Available O presente trabalho objetivou avaliar a ação dos isolados JAB 07, CB 7 e AM 9 do fungo Beauveria bassiana para ovos, larvas e ninfas ingurgitadas de Rhipicephalus sanguineus. Padronizou-se a concentração de 109 conídios mL-1 para cada isolado e por meio de diluições seriadas, obtiveram-se as suspensões com concentrações de 10(8 e 10(7con. mL-1. Preparou-se um bioensaio para cada fase do ciclo de vida do carrapato. Cada ensaio foi composto por 10 grupos tratamentos, formados por um isolado do fungo e uma concentração de conídios, e um grupo controle contendo apenas o veículo das suspensões. Os isolados do fungo, aplicados nas diferentes concentrações de esporos, causaram redução no percentual de eclosão de larvas oriundas de ovos infectados (0,7 a 12,1% de eclosão e no percentual de ecdise de larvas (4,7 a 33,7% de ecdise e ninfas (0 a 16,7% de ecdise. Não houve diferença entre os isolados (P>0,05 quanto à infecção de ovos, mas a aplicação de 109 con./mL de JAB 07 e AM 9 promoveu redução significativa da eclosão de larvas, em relação à concentração de 10(7con. mL-1. O isolado CB 7 foi o mais eficaz na redução do número de ecdises de larvas. Os isolados e as concentrações de conídios não diferiram (P>0,05 quanto à capacidade de redução do percentual de ecdise de ninfas, mas evidenciou-se intensa atividade patogênica do fungo.The aim of the present study was to determine the action of isolates JAB 07, CB 7 and AM 9 of the fungus Beauveria bassiana on eggs, larvae and engorged nymphs of Rhipicephalus sanguineus tick. A concentration of 109 conidia mL-1 was standardized for each isolate and suspensions containing 10(8 and 10(7 conidia mL-1 were obtained by serial dilution. A bioassay was prepared for each phase of the life cycle of the tick. Each assay comprised 10 treatment groups, consisting of one fungal isolate and one conidial concentration, and one control group containing only the vehicle of

  13. HISTOLOGICAL STUDY ON INTERNAL ORGANS DEVELOPMENT OF MANGROVE SNAPPER, Lutjanus argentimaculatus LARVAE

    Directory of Open Access Journals (Sweden)

    Ketut Mahardika

    2012-12-01

    Full Text Available Mangrove snapper, Lutjanus argentimaculatus is one of highly economic value of marine fish commodity. Culture of this species has been developed a few years ago. Basic data on biological aspect is still limited whereas those kinds of information are needed. Histological study to determine development of internal organs of the larvae of mangrove snapper was conducted. Amount of 15-20 larvae each from 1 day after DAH hatching (1 DAH up to 30 days after hatching (30 DAH were collected, fixed in Bouin’s solution for 4-6 hours and then transferred into 70% alcohol. The samples were then embedded in paraffin wax and the sections were stained with haematoxylineosin (H&E. Results showed that the eye retina of the mangrove snapper larvae well developed on 3 DAH, whereas their digestive tract was on 5 DAH. Under this condition, the larvae started feeding as showed by present of natural food tissues in the intestine. Development of digestive tract and other internal organs reached their complete form like in adult fish after 20 DAH.

  14. Fly larvae as sustainable bioconverters of waste for feed in the future

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Aabo, Søren

    2014-01-01

    How to provide enough food and feed for the growing population is a major challenge for the nextgeneration. Improved economy in many developing countries increases the demand for protein from meator fish. This may lead to depletion of the seas and overexploitation of agricultural land in the in s......How to provide enough food and feed for the growing population is a major challenge for the nextgeneration. Improved economy in many developing countries increases the demand for protein from meator fish. This may lead to depletion of the seas and overexploitation of agricultural land......, or nutrients may be refined fromprocessed insects, however there is a huge need for technological development in order to automateculture and harvest of the insects.In nature insects and insect larvae are important feed sources for poultry and the larva of the commonhouse fly (Musca domestica) have been shown...... to be especially rich in essential amino and fatty acids. Atthe Food institute we have investigated in feed safety of using these fly larvae as feed for egg laying hens.The larvae were reared on poultry manure which implies the risk of transmission of pathogenicmicroorganism between animals and to humans, as well...

  15. Behavioral Responses of Concholepas concholepas (Bruguière, 1789) Larvae to Natural and Artificial Settlement Cues and Microbial Films.

    Science.gov (United States)

    Rodriguez, S R; Riquelme, C; Campos, E O; Chavez, P; Brandan, E; Inestrosa, N C

    1995-12-01

    The behavioral responses of veliger larvae of the gastropod Concholepas concholepas were studied in the presence of different natural and artificial settlement cues and microbial films. Early pre-competent larvae stopped swimming, sank (due to ciliary arrests, retraction of the velum into the shell, or both), and remained inactive on the substratum when exposed to conspecific mucus and hemolymph. In both cases the effect was time-dependent and the number of larvae showing these behaviors decreased over time. Larvae exposed to NH4Cl (ammonium ion) showed a similar time- and dose-dependent response. A positive and time-dependent response was also observed when larvae were exposed to different extracellular matrix (ECM) components (i.e., collagen, gelatin, and fibronectin) and sulfated polysaccharides (i.e., carrageenan, heparin, and chondroitin sulfate). In this case the larvae remained attached to the substratum. However, the effect of sulfated polysaccharides on C. concholepas larval behavior was faster than that observed with other ECM molecules. We also studied the responses of premetamorphic C. concholepas larvae exposed to different microbial films. In chemotaxis experiments with different films, with glass as the substratum, larvae showed a significant preference for multispecific and diatoms films. When shells of C. concholepas were used as the substratum, the preference for multispecific films was clear and significant. Likewise, larvae showed velar contractions in the presence of all the films tested. Larvae exposed to multispecific films and to the microalga Prasinocladus marinus showed an increased ciliar movement. The finding that mucus and hemolymph of conspecific adults and ECM molecules (mainly sulfated polysaccharides) induce the cessation of swimming of C. concholepas larvae suggests a possible role for cell-surface receptors in mediating the larval response of marine organisms. Likewise, the positive chemotaxis responses of C. concholepas larvae to

  16. Susceptibility of irradiated Galleria mellonella F1Larvae to Entomopathogenic Nematodes

    International Nuclear Information System (INIS)

    Salem, H.M.; Rizk, S.A.; Sayed, R.M.; Hussein, M.A; Hafez, S.E

    2008-01-01

    Combined effect of substerilizing doses of gamma radiation (40 and 100 Gy) and different concentrations of entomopathogenic nematodes (20, 40, 60, and 80 IJs) on the greater wax moth, Galleria mellonella was studied. The 4th larval instar resulted from irradiated male parent pupae mated with normal female were tested for susceptibility to Heterorhabditis bacteriophora BA1 and Steinernema carpocapsae BA2. The mortality rate of the larvae increased by increrasing radiation dose and nematode concentrations. The reproduction of both nematode strains decreased significantly with increasing the treatments (radiation dose and nematode concentrations). In addition, exposure to gamma radiation and entomopathogenic nematodes significantly decreased the total haemocyte count (THC) of the larvae with increasing radiation doses (40 and 100 Gy) and both nematode strains concentrations (20 and 40 IJs) and reached the minimal count at the combiend effect. Finally, larvae were more susceptible to Steinernema carpocapsa than Heterorhabditis bacteriophora. (author)

  17. Dose/dose-rate responses of shrimp larvae to UV-B radiation

    International Nuclear Information System (INIS)

    Damkaer, D.M.

    1981-01-01

    Previous work indicated dose-rate thresholds in the effects of UV-B on the near-surface larvae of three shrimp species. Additional observations suggest that the total dose response varies with dose-rate. Below 0.002 Wm -2 sub([DNA]) irradiance no significant effect is noted in activity, development, or survival. Beyond that dose-rate threshold, shrimp larvae are significantly affected if the total dose exceeds about 85 Jm -2 sub([DNA]). Predictions cannot be made without both the dose-rate and the dose. These dose/dose-rate thresholds are compared to four-year mean dose/dose-rate solar UV-B irradiances at the experimental site, measured at the surface and calculated for 1 m depth. The probability that the shrimp larvae would receive lethal irradiance is low for the first half of the season of surface occurrence, even with a 44% increase in damaging UV radiation. (orig.)

  18. Dose/dose-rate responses of shrimp larvae to UV-B radiation

    Energy Technology Data Exchange (ETDEWEB)

    Damkaer, D.M.; Dey, D.B.; Heron, G.A.

    1981-01-01

    Previous work indicated dose-rate thresholds in the effects of UV-B on the near-surface larvae of three shrimp species. Additional observations suggest that the total dose response varies with dose-rate. Below 0.002 Wm/sup -2/sub((DNA)) irradiance no significant effect is noted in activity, development, or survival. Beyond that dose-rate threshold, shrimp larvae are significantly affected if the total dose exceeds about 85 Jm/sup -2/sub((DNA)). Predictions cannot be made without both the dose-rate and the dose. These dose/dose-rate thresholds are compared to four-year mean dose/dose-rate solar UV-B irradiances at the experimental site, measured at the surface and calculated for 1 m depth. The probability that the shrimp larvae would receive lethal irradiance is low for the first half of the season of surface occurrence, even with a 44% increase in damaging UV radiation.

  19. Fish larvae from the Gulf of California

    Directory of Open Access Journals (Sweden)

    Gerardo Aceves-Medina

    2003-03-01

    Full Text Available Taxonomic composition of fish larvae was analysed from 464 plankton samples obtained during 10 oceanographic surveys in the Gulf of California between 1984 and 1988. We identified 283 taxa: 173 species, 57 genera, and 53 families. Tropical and subtropical species predominated except during the winter, when temperate-subarctic species were dominant. The most abundant species were the mesopelagic Benthosema panamense, Triphoturus mexicanus and Vinciguerria lucetia, but the coastal pelagic species Engraulis mordax, Opisthonema spp., Sardinops caeruleus and Scomber japonicus were also prominent. The taxonomic composition of the ichthyoplankton shows the seasonality of the Gulf as well as environmental changes that occurred between the 1984-1987 warm period and the 1956-1957 cool period previously reported. The presence of E. mordax larvae as one of the most abundant species in the Gulf provides evidence of the reproduction of this species two years before the development of the northern anchovy fishery and the decline of the sardine fishery in the Gulf of California.

  20. Observations of cocooned Hydrobaenus (Diptera: Chironomidae) larvae in Lake Michigan

    Science.gov (United States)

    Tucker, Taaja R.; Hudson, Patrick L.; Riley, Stephen

    2016-01-01

    Larvae of the family Chironomidae have developed a variety of ways to tolerate environmental stress, including the formation of cocoons, which allows larvae to avoid unfavorable temperature conditions, drought, or competition with other chironomids. Summer cocoon formation by younger instars of the genus Hydrobaenus Fries allows persistence through increased temperatures and/or intermittent dry periods in arid regions or temporary habitats, but this behavior was not observed in the Great Lakes until the current study. Cocoon-aestivating Hydrobaenus sp. larvae were found in benthic grab samples collected in 2010–2013 near Sleeping Bear Dunes National Lakeshore in northern Lake Michigan with densities up to 7329/m2. The aestivating species was identified as Hydrobaenus johannseni (Sublette, 1967), and the associated chironomid community was typical for an oligotrophic nearshore system. Hydrobaenus cocoon formation in the Great Lakes was likely previously unnoticed due to the discrepancies between the genus' life history and typical benthos sampling procedures which has consequences for describing chironomid communities where Hydrobaenus is present.

  1. EFECTO INSECTICIDA DEL EXTRACTO DE Bocconia frutescens L. SOBRE LARVAS DE CHISAS

    Directory of Open Access Journals (Sweden)

    CONSUELO MONTES R

    2013-12-01

    Full Text Available Esta investigación se realizó en el municipio de Puracé Cauca, para evaluar el efecto insecticida del extracto de Bocconia frutescens sobre larvas de chisa Ancognatha vulgaris. Se empleo un diseño de bloques completos al azar, con cinco tratamientos y tres repeticiones. Los tratamiento T1, T2 y T3 corresponden a concentraciones de 14%, 17% y 20 % del extracto de zarcillejo, T4 tratamiento químico (Carbofuran y T5 Testigo. Las variables evaluadas fueron: presencia de larvas de chisas sanas y larvas afectadas, daño en plantas, evaluado como intensidad y porcentaje de infestación. Se presentaron diferencias significativas para las variables: intensidad e infestación, larvas de chisas sanas y afectadas-muertas, en diferentes días de evaluación. El mejor tratamiento fue el T2, seguido por T3 y T1. Para el porcentaje de daño causado a la planta los mejores tratamientos fueron T2 y T5 con 57% para intensidad y para infestación 55% y 45% en T2 y T3. El análisis fitoquímico mostró la presencia de alcaloides, terpenos, antronas y cumarinas en el extracto. El efecto causado por el extracto sobre las larvas fue deshidratación y flacidez hasta provocar la muerte, lo cual se atribuyea la acción de alguno de sus metabòlitos o la combinación de varios.

  2. Oceanographic and behavioural assumptions in models of the fate of coral and coral reef fish larvae.

    Science.gov (United States)

    Wolanski, Eric; Kingsford, Michael J

    2014-09-06

    A predictive model of the fate of coral reef fish larvae in a reef system is proposed that combines the oceanographic processes of advection and turbulent diffusion with the biological process of horizontal swimming controlled by olfactory and auditory cues within the timescales of larval development. In the model, auditory cues resulted in swimming towards the reefs when within hearing distance of the reef, whereas olfactory cues resulted in the larvae swimming towards the natal reef in open waters by swimming against the concentration gradients in the smell plume emanating from the natal reef. The model suggested that the self-seeding rate may be quite large, at least 20% for the larvae of rapidly developing reef fish species, which contrasted with a self-seeding rate less than 2% for non-swimming coral larvae. The predicted self-recruitment rate of reefs was sensitive to a number of parameters, such as the time at which the fish larvae reach post-flexion, the pelagic larval duration of the larvae, the horizontal turbulent diffusion coefficient in reefal waters and the horizontal swimming behaviour of the fish larvae in response to auditory and olfactory cues, for which better field data are needed. Thus, the model suggested that high self-seeding rates for reef fish are possible, even in areas where the 'sticky water' effect is minimal and in the absence of long-term trapping in oceanic fronts and/or large-scale oceanic eddies or filaments that are often argued to facilitate the return of the larvae after long periods of drifting at sea. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  3. Gelatinous plankton is central to the diet of European eel (Anguilla anguilla) larvae in the Sargasso Sea

    DEFF Research Database (Denmark)

    Ayala, Daniel Jiro; Munk, Peter; Lundgreen, Regitze B. C.

    2018-01-01

    endangered species. Next-generation 18S rRNA gene sequencing data of Sargasso Sea eel larvae gut contents and marine snow aggregates was compared with a reference plankton database to assess the trophic relations of eel larvae. Gut contents of A. anguilla larvae were not well explained by the eukaryotic...

  4. Pathogenicity Assay of Vibrio harveyi in Tiger Shrimp Larvae Employing Rifampicin-Resistant as A Molecular Marker

    Directory of Open Access Journals (Sweden)

    . Widanarni

    2007-12-01

    Full Text Available Rifampicin-resistant marker was employed as a reporter to assay pathogenicity of Vibrio harveyi  in shrimp larvae.  V. harveyi M. G3 and G7 that difference not schizotyping as shown by Pulsed-Filed Gel Electrophoresis (PFGE used in this study. Spontaneous mutation was conducted to generate V. harveyi resistant to rifampicin. Two groups of shrimp post-larvae (PL5 were immersed for 30 min in 106 CFU/ml of mutants and wild type of V. harveyi, respectively; and then placed in a 2 liter shrimp rearing tank for five days. A control group was immersed in sterile seawater. Growth curve analysis and pathogenicity assay of V. harveyi  showed that each of the V. harveyi mutant exhibited almost identical profiles to that of the wild type parental strain and did not show alteration in their pathogenicity. Sample from dead shrimp larvae showed that the dead shrimp larvae were infected by V. harveyi RfR, indicated that rifampicin-resistant marker effective as a reporter to assay pathogenicity of Vibrio harveyi in shrimp larvae. Key words: shrimp larvae, Vibrio harveyi, rifampicin-resistant, molecular marker

  5. The gut microbiota in larvae of the housefly Musca domestica and their horizontal transfer through feeding.

    Science.gov (United States)

    Zhao, Yao; Wang, Wanqiang; Zhu, Fen; Wang, Xiaoyun; Wang, Xiaoping; Lei, Chaoliang

    2017-12-01

    House fly larvae provide a prolific and sustainable source of proteins used in poultry and fish feed. Wheat bran is a superior diet for house fly larvae and has been widely investigated to exploit its potential in the food and feed area. Using Illumina MiSeq 16S rDNA sequencing, this study investigated the gut microbiota of house fly larvae feeding on wheat bran and the bacterial community in the wheat bran. The bacterial communities in the house fly larvae were dominated by the phyla Proteobacteria and Firmicutes. Enterobacteriaceae and Providencia were the predominant bacteria at the family and genus levels, respectively. Some bacteria in the phyla Actinobacteria, Proteobacteria, Bacteroidetes and Firmicutes may be transferred from the gut of house flies to the wheat bran during feeding and may be involved in degrading and utilizing polysaccharides in the cell wall of wheat bran. The significance of the gut microbiota of house fly larvae, their transferring and roles in degradation of wheat bran is discussed. These findings regarding the gut microbiota of house fly larvae will provide opportunities for research on the impact of microbial communities on poultry and fish.

  6. Effects of Foodstuffs on Intestinal Length in Larvae of Rhacophorus arboreus (Anura: Rhacophoridae) : Developmental Biology

    OpenAIRE

    SHINRI, HORIUCHI; YUTAKA, KOSHIDA; Department of Biology, College of General Education, Osaka University; Department of Biology, College of General Education, Osaka University

    1989-01-01

    Correlation between foodstuffs and intestinal length was examined in larvae of Rhacophorus arboreus (Anura: Rhacophoridae). The larva, being heterophagous, has a tube-like intestine provided with neither epithelial outfoldings nor villi, and intestinal length is found to be a good morphological index of digestive and absorptive functions of the intestine. The results obtained were summarized as follows: The grown larva fed on boiled spinach had an intestine more than 1.5 times as long as that...

  7. Toxicity of cypermethrin on the embryo and larvae of Gangetic mystus, Mystus cavasius

    NARCIS (Netherlands)

    Ali, Md Haider; Sumon, Kizar Ahmed; Sultana, Marin; Rashid, Harunur

    2018-01-01

    The objective of the present study was to elucidate the effects of cypermethrin on the embryo and the larvae of Gangetic mystus, Mystus cavasius. Therefore, fertilized eggs (n = 100) and 1-day-old larvae (n = 100) were exposed to six different concentrations of cypermethrin (0, 2, 4, 8, 16 and 32 μg

  8. Comparison of three artificial digestion methods for detection of non-encapsulated Trichinella pseudospiralis larvae in pork

    DEFF Research Database (Denmark)

    Nockler, K.; Reckinger, S.; Szabo, I.

    2009-01-01

    In a ring trial involving five laboratories (A, B, C, D, and E), three different methods of artificial digestion were compared for the detection of non-encapsulated Trichinella pseudospiralis larvae in minced meat. Each sample panel consisted often 1 g minced pork samples. All samples in each panel...... were derived from a bulk meat preparation with a nominal value of either 7 or 17 larvae per g (Ipg). Samples were tested for the number of muscle larvae using the magnetic stirrer method (labs A, B, and E), stomacher method (lab B), and Trichomatic 35 (R) (labs C and D). T. pseudospiralis larvae were...... by using the magnetic stirrer method (22%), followed by the stomacher method (25%), and Trichomatic 35 (R) (30%). Results revealed that T. pseudospiralis larvae in samples with a nominal value of 7 and 17 Ipg can be detected by all three methods of artificial digestion....

  9. Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

    Science.gov (United States)

    López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

    2017-02-01

    Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

  10. Efikasi Ekstrak Daun dan Bunga Kecombrang (Etlingera elatior terhadap Larva Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Meiske Elisabeth Koraag

    2016-12-01

    Full Text Available Abstract. Three widely known dengue vector control programs in Indonesia are chemical, biological, and environmental modification control where chemical control with organophosphate insecticide (malathion and temephos is the most common. The long term use of chemical insecticide will result in the vector beingtolerant and eventually resistant to insecticide. One of the alternative solutions is to use biological larvacide from the plant. The objective of this study was to determine the lethal concentration of the extract of Kecombrang (Etlingera elatior leaves and flowers against Aedes aegypti larvae. This was an experimentalstudy where the sample size was determined by using the Federer formula. The study used six different concentrations and four repetitions. Two controls group, Bacillus thuringiensis and water used as positive and negative control. The results showed that the LC50 and LC90 of Kecombrang leave extract were 1.20% and 2.05% respectively whereas for Kecombrang flowers extract were 0,05% and 0.09% respectively. Extract of Kecombrang leaves and flowers is effective to kill Ae. aegypti larvae where the flowers extract is more effective than the leaves extract in killing Ae. aegypti larvae.Keywords: dengue, Ae. aegypti, larvae, Etlingera elatiorAbstrak. Pengendalian vektor penular demam berdarah dengue (DBD yang selama ini dikenal yaitu pengendalian secara kimia, biologi dan modifikasi lingkungan. Pengendalian vektor DBD di Indonesia masih banyak dilakukan dengan menggunakan insektisida dari golongan organofosfat (malation dan temefos. Penggunaan insektisida kimia dalam jangka waktu lama akan memberi efek menekan dan menyeleksi serangga vektor sasaran untuk menjadi toleran sampai resisten. Salah satu solusi alternatif yaitu menggunakan larvasida yang berasal dari tanaman. Penelitian ini bertujuan untuk menentukan daya bunuh ekstrak daun dan bunga kecombrang (Etlingera elatior terhadap larva nyamuk Ae. aegypti. Jenis penelitian yang

  11. Tracking radioactive larvae of Strongyloides ratti in the host

    International Nuclear Information System (INIS)

    Wilson, P.A.G.

    1979-01-01

    Infective larvae of homogonic Strongyloides ratti grown in faecal culture with 32 P or 75 Se acquired a significant amount of radioactivity which was firmly attached to them. Heating removed most of the 32 P but left 75 Se in place. Subcutaneous injection of virgin and nursing mother rats with living and heat-killed ratioactive larvae resulted in a pattern of labelling in the small intestine of injected animals and, in the case of 75 Se, those of suckling pups, which can only be explained if labelled worms follow the natural migratory routes. The use of this tool in migratory studies is discussed, with precautions to allow for flaws in the technique. (author)

  12. Microvascular system forming in skeletal muscle near trichinella larvae

    International Nuclear Information System (INIS)

    Berzentsev, Y.A.; Oksov, I.V.

    1986-01-01

    The fine structure and dynamics of formation of the microcirculatory system about the larvae of the two Trichinella species, providing for the rapid entry of nutrient substances to the larvae, were investigated in the muscles of white mice. Hitological, hitochemical, autoradiographic, and electron-microscopic methods were used in the investigation. At a certain period of the experiment, the greatest quantity of RNA was found in the endotheliocyte cytoplasm, tritium-thymidine label was incorporated into the nuclei, and mitoses were visible. The transition to tissue parasitism was accompanied by a complication of the relationships with the host and the formation of a more complex independent microcirculatory system, which ensures a more intensive influx of blood

  13. Nueva especie de Parathelohania (Microsporidia en larvas de Anopheles aquasalis (Diptera: Culicidae en Venezuela

    Directory of Open Access Journals (Sweden)

    Frances Osborn

    2002-12-01

    Full Text Available Se describen los síntomas en larvas de A. aquasalis infectadas naturalmente con un microsporidio parasítico, y la ultraestructura de las esporas del mismo. Las larvas fueron criadas bajo condiciones de laboratorio en concentraciones de salinidad de 10 g/l y 20 g/l, registrándose diariamente la mortalidad y la fecha del cambio de estadío de las mismas. Las larvas infectadas fueron procesadas por rnicroscopía electrónica de transmisión usando métodos convencionales con pH 7.2 y 260 mOsm/I. El incremento de la infección por los microsporidios estuvo correlacionado positivamente con un aumento en la duración promedio del cuarto estadío de 2.88 a 6.33 días en 10 g/l de sal y de 2.47 a 6.14 días en 20 g/l. La mortalidad de las larvas también aumentó en aproximadamente 50% durante este estadío a ambas concentraciones de salinidad. No se observaron estas alteraciones en los otros estadíos. Las esporas maduras de los microsporidios fueron encontradas en el intestino de las larvas. Estas esporas mostraron forma de barril y dimensiones de 2.6 x 2.4 µm aproximadamente. La reducción en la supervivencia de las larvas de A. aquasalis infectadas con los microsporidios, y el aumento del tiempo de su desarrollo sugiere que este parásito podría ser un posible controlador biológico de esta plaga. El microsporidio descrito presenta características similares a las del género Parathelohania. Se sugiere que el microsporidio encontrado en las larvas de A. aquasalis es una especie nueva y se propone nombrarla Parathelohania aquasalensis. Este trabajo representa el primer reporte de un microsporidio encontrado en un díptero en Venezuela.The symptoms of Anopheles aquasalis larvae naturally infected by a microsporidium, and the ultrastructure of the infecting spores is describes. The larvae were maintained under laboratory conditions in salt concentrations of 10 g/l and 20 g/l of water. Daily recordings of the mortality of the larvae were made and

  14. Temperature Dependence of Respiration in Larvae and Adult Colonies of the Corals Acropora tenuis and Pocillopora damicornis

    Directory of Open Access Journals (Sweden)

    Dwi Haryanti

    2015-06-01

    Full Text Available Although algal symbionts can become a source of reactive oxygen species under stressful conditions, symbiotic planulae of the coral Pocillopora damicornis are highly tolerant to thermal stress compared with non-symbiotic planulae of Acropora tenuis. As a first step to understand how P. damicornis planulae attain high stress tolerance, we compared the respiration rate and temperature dependence between symbiotic planulae of P. damicornis and non-symbiotic planulae of A. tenuis, as well as between larvae and adult branches within each species. Larvae and adult branches of both species had similar temperature dependency of respiration rate, with the temperature coefficient (Q10 values of about 2. Planula larvae of P. damicornis had a significantly lower respiration rate than that of A. tenuis larvae at 25–30 °C, but not at 32 °C, whereas adult branches of P. damicornis had a significantly higher respiration rate than that of A. tenuis branches at all temperatures. Thus, P. damicornis larvae appear to be capable of reducing their respiration rate to a greater extent than A. tenuis larvae, which could partly explain why P. damicornis larvae had high survivorship under thermal stress, although other antioxidant or photoprotective mechanisms should be investigated in the future.

  15. A sleep state in Drosophila larvae required for neural stem cell proliferation

    Science.gov (United States)

    Szuperak, Milan; Churgin, Matthew A; Borja, Austin J; Raizen, David M; Fang-Yen, Christopher

    2018-01-01

    Sleep during development is involved in refining brain circuitry, but a role for sleep in the earliest periods of nervous system elaboration, when neurons are first being born, has not been explored. Here we identify a sleep state in Drosophila larvae that coincides with a major wave of neurogenesis. Mechanisms controlling larval sleep are partially distinct from adult sleep: octopamine, the Drosophila analog of mammalian norepinephrine, is the major arousal neuromodulator in larvae, but dopamine is not required. Using real-time behavioral monitoring in a closed-loop sleep deprivation system, we find that sleep loss in larvae impairs cell division of neural progenitors. This work establishes a system uniquely suited for studying sleep during nascent periods, and demonstrates that sleep in early life regulates neural stem cell proliferation. PMID:29424688

  16. [Organic waste treatment by earthworm vermicomposting and larvae bioconversion: review and perspective].

    Science.gov (United States)

    Zhang, Zhi-jian; Liu, Meng; Zhu, Jun

    2013-05-01

    There is a growing attention on the environmental pollution and loss of potential regeneration of resources due to the poor handling of organic wastes, while earthworm vermicomposting and larvae bioconversion are well-known as two promising biotechnologies for sustainable wastes treatments, where earthworms or housefly larvae are employed to convert the organic wastes into humus like material, together with value-added worm product. Taken earthworm ( Eisenia foetida) and housefly larvae ( Musca domestica) as model species, this work illustrates fundamental definition and principle, operational process, technical mechanism, main factors, and bio-chemical features of organisms of these two technologies. Integrated with the physical and biochemical mechanisms, processes of biomass conversion, intestinal digestion, enzyme degradation and microflora decomposition are comprehensively reviewed on waste treatments with purposes of waste reduction, value-addition, and stabilization.

  17. Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470 Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Bento Fernandes

    2011-09-01

    Full Text Available The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae, so that we always had 10 larvae of fish at each aquarium after each counting. For both fish species, there was a slight increase in consumption by the Odonate with intermediate size, but the values did not differ statistically (p > 0.05. Larvae of Odonate in the treatments with greater length presented a lower consumption (p The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae

  18. Effects of parsley and camphor oils on mortality and trace elements of Chrysomyia albiceps larvae

    International Nuclear Information System (INIS)

    Rizk, S.A.; El- Sebaay, S.S.; Amin, M.M.

    2010-01-01

    The use of plant oils to protect sheep and other animals from infestation and myiasis of medical and veterinary pests are limited. This study aimed to evaluate the effect of parsley oil (Petroselimum crispum) and camphor oil (Cinnamomum camphora) on mortality of Chrysomayia albiceps larvae and their effects on metal contents of the larvae. When the parsley oil used at the concentrations of 25, 50 and 100%, the larval mortality percent was increased with the decrease of the concentration and it reached 100% when the solvent used alone without oil. The pupation and the emergence percents decreased with the decrease of the concentration. The sex ratio was in favor of males at all concentrations except at the concentration of 100% where it was in favor of females. When camphor oil was used at concentrations of 25, 50, and 100%, the larval mortality percent was decreased with the decrease of the concentration and it reached 100% when the solvent was used alone without oil. The pupation percent increased with the decrease of the concentration. The emergence percent were similar in different treatments. The sex ratio was in favor of males at all concentrations except in the concentration of 50% it was in favor of females. In addition, the present study investigated the effect of parsley and camphor oils on the trace elements in the larval whole body. Eleven elements in C. albiceps larvae (untreated and treated with solvent (ethyl alcohol) and different concentrations of parsley oil) were detected. In untreated larvae Phosphorous was the most abundant element followed by magnesium and the least abundant element was ferric. In larvae treated with the solvent only (ethyl alcohol) potassium was the most abundant element followed by phosphorous and the least abundant element was ferric. In larvae treated with parsley oil at concentration of 25%, the elemental arrangement appeared to be similar to that of larvae treated with the solvent only. On the other hand, at the

  19. Predation efficiency of Anopheles gambiae larvae by aquatic predators in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Nyindo Mramba

    2011-07-01

    Full Text Available Abstract Background The current status of insecticide resistance in mosquitoes and the effects of insecticides on non-target insect species have raised the need for alternative control methods for malaria vectors. Predation has been suggested as one of the important regulation mechanisms for malaria vectors in long-lasting aquatic habitats, but the predation efficiency of the potential predators is largely unknown in the highlands of western Kenya. In the current study, we examined the predation efficiency of five predators on Anopheles gambiae s.s larvae in 24 hour and semi- field evaluations. Methods Predators were collected from natural habitats and starved for 12 hours prior to starting experiments. Preliminary experiments were conducted to ascertain the larval stage most predated by each predator species. When each larval instar was subjected to predation, third instar larvae were predated at the highest rate. Third instar larvae of An. gambiae were introduced into artificial habitats with and without refugia at various larval densities. The numbers of surviving larvae were counted after 24 hours in 24. In semi-field experiments, the larvae were counted daily until they were all either consumed or had developed to the pupal stage. Polymerase chain reaction was used to confirm the presence of An. gambiae DNA in predator guts. Results Experiments found that habitat type (P P P P An. gambiae DNA was found in at least three out of ten midguts for all predator species. Gambusia affins was the most efficient, being three times more efficient than tadpoles. Conclusion These experiments provide insight into the efficiency of specific natural predators against mosquito larvae. These naturally occurring predators may be useful in biocontrol strategies for aquatic stage An. gambiae mosquitoes. Further investigations should be done in complex natural habitats for these predators.

  20. Evaluation of culture media for Paenibacillus larvae applied to studies of antimicrobial activity Evaluación de medios de cultivo para el crecimiento de Paenibacillus larvae aplicables en estudios de actividad antimicrobiana

    Directory of Open Access Journals (Sweden)

    L. B. Gende

    2008-09-01

    Full Text Available This study was conducted to compare different liquid culture media for Paenibacillus larvae growth in order to find the best one to be used in studies on activity of antimicrobial substances, such as essential oils. P. larvae presented poor growth in usual broths such as Mueller-Hinton, commonly employed in antimicrobial activity assays. Growth in liquid media was evaluated using Paenibacillus larvae strains isolated from hives located in different geographical zones. The MYT medium (Mueller-Hinton broth, yeast extract and thiamine was selected out of the eight liquid media analyzed, as it proved to be the most adequate due to its higher absorbance at 620 nm. The following mean values were obtained from the four P. larvae strains: 0.227 ± 0.016 for the Cobo strain, 0.279 ± 0.015 for La Plata strain, 0.758 ± 0.020 for Mechongué strain and 0.244 ± 0.0079 for Sierra de los Padres strain, respectively.Este trabajo está orientado a comparar diferentes medios de cultivo líquidos para el crecimiento de Paenibacillus larvae. El objetivo fue encontrar el más apropiado para utilizar en estudios de actividad antimicrobiana de diferentes sustancias, tales como aceites esenciales. P. larvae presenta un crecimiento débil en medios de cultivo como el Mueller-Hinton, comúnmente usado en ensayos de actividad antimicrobiana. Se evaluó el crecimiento en caldos de cultivo de cepas aisladas de colmenas ubicadas en diferentes zonas geográficas. De los ocho medios analizados, el MYT (Mueller-Hinton, extracto de levadura y tiamina mostró ser el más apropiado, en éste se observó el mayor valor de absorbancia a 620 nm. Los valores obtenidos en promedio para los cuatro aislamientos de P. larvae evaluados fueron 0,227 ± 0,016 (cepa de Cobo; 0,279 ± 0,015 (cepa de La Plata; 0,758 ± 0,020 (cepa de Mechongué y 0,244 ± 0,0079 (cepa de Sierra de los Padres.

  1. Effectiveness of Metarhizium anisopliae and Entomopathogenic Nematodes to Control Oryctes rhinoceros Larvae in the Rainy Season.

    Science.gov (United States)

    Indriyanti, Dyah Rini; Widiyaningrum, Priyantini; Haryuni; Slamet, Muji; Maretta, Yoris Adi

    2017-01-01

    Metarhizium anisopliae (MET) and entomopathogenic nematodes (EPN) are microorganisms that attack the larvae of Oryctes rhinoceros. The effects of MET, EPN and the combination of both on the O. rhinoceros larvae were studied during the rainy season in Jepara Indonesia. This study aimed to determine the effectiveness of Metarhizium anisopliae and entomopathogenic nematodes to control Oryctes rhinoceros larvae in the rainy season. There were four level doses of MET, four level doses of EPN and four mixture of MET and EPN. The experiment used 72 containers that were placed in the garden with coconut palm shade. Five kilograms of organic soil that was mixed with biological control agents (MET, EPN and MET+EPN) and ten O. rhinoceros larvae 3rd instar were put in each other container. The data were analyzed by descriptive analysis. Every larvae mortality was observed once a week and observations are for 8 weeks. The result showed that the larval mortality due to MET treatment occurred on 2nd-7th week. Meanwhile, the larval mortality due to EPN treatment took place on 2nd-8th weeks and the larval mortality due to MET+EPN treatment occurred on 1st-5th weeks. The combination of MET and EPN was simultaneously effective to control O. rhinoceros larvae than separate use of MET or EPN. Result of this study showed that using two agents of biocontrol was more effective, so that it can be beneficial for controlling O. rhinoceros larvae in the field.

  2. Resistance Detection of Aedes aegypti Larvae to Cypermethrin from Endemic Area in Cimahi City West Java

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    Endang Puji Astuti

    2014-06-01

    Full Text Available Vector control programs using chemical insecticide e.g organochlorin, organophosphate, carbamate, and pyrethroid (cypermethrin. When those insecticides were applied continuously, it may lead to vector resistance. The aim of this research was to detect any resistance of Ae. aegypti to cypermethrin in endemic areas of Cimahi. This research is a laboratory study that used biochemical test which referred to Lee’s method. Larva samples were collected from 8 villages, which are endemic area. Samples of larvae were collected from 15 villages belonged to dengue endemic areas in town of Cimahi, however, villages that meet the availability of larvae were only 8 villages. To detect the activity of monooxygenase enzyme, a biochemical assay was used in this research by created a reaction between larvae homogenate and sodium acetate substrate. The results of reaction were read using ELISA reader with spectrophotometer wave length of 595 nm. Overall, the results showed that most of the larvae in eight villages of Cimahi is still susceptible to cypermethrin. However, larvae from Cibabat village were 4% resistant, 2% tolerant, and 94% susceptible. On the other hand, Cigugur village showed that 12.7% larvae were tolerant and 87.3% still susceptible. Other villages like Cimahi, Cibeureum, Melong, Baros, Cipageran, and Pasirkaliki still remains susceptible. Resistance detection using biochemical assay of cypermethrin insecticide for Ae.aegypti resulting data stated that in 6 villages were still susceptible but in 3 other villages were already tolerant and 1 village was already resistance.

  3. Effects of irradiation on the biology of the infective larvae of Toxocara canis in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Barriga, O.O.; Myser, W.C.

    1987-02-01

    Mice were infected with either 2000 normal or irradiated embryonated eggs of Toxocara canis and the number of larvae in their livers, lungs, brains, and carcasses investigated at 5, 20, and 33 days of infection. Mortality of mice infected with normal eggs was 33% between day 4 and 8 postinfection but there was no mortality among mice infected with irradiated eggs. Irradiation with 60, 90, or 150 kr of X-rays inhibited the migration of larvae from the livers and lungs and their accumulation in brain and carcass in proportion to the irradiation dose. By day 33 of infection, the ratio of larvae in liver and lungs to larvae in brain and carcass was 0.16 in normal mice, 0.42 in 60-kr mice, 0.98 in 90-kr mice, and 23.3 in 150-kr mice. Irradiated larvae, particularly those migrating through the peritoneal cavity, died faster than normal larvae until day 20. Irradiation favored survival after day 20. By days 20 and 33 postinfection the total parasite load was 29% and 8%, respectively, of the administered dose in control mice, 18% and 12% in 60-kr mice, 8% and 4% in 90-kr mice, and 0.9% and 0.3% in 150-kr mice. Irradiation of infective T. canis larvae, then, reduces their pathogenicity, inhibits their migration from liver and lungs, kills some of the parasites during the first 3 weeks of infection, but favors their late survival in the host.

  4. Comparison of three artificial digestion methods for detection of non-encapsulated Trichinella pseudospiralis larvae in pork.

    Science.gov (United States)

    Nöckler, K; Reckinger, S; Szabó, I; Maddox-Hyttel, C; Pozio, E; van der Giessen, J; Vallée, I; Boireau, P

    2009-02-23

    In a ring trial involving five laboratories (A, B, C, D, and E), three different methods of artificial digestion were compared for the detection of non-encapsulated Trichinella pseudospiralis larvae in minced meat. Each sample panel consisted of ten 1g minced pork samples. All samples in each panel were derived from a bulk meat preparation with a nominal value of either 7 or 17 larvae per g (lpg). Samples were tested for the number of muscle larvae using the magnetic stirrer method (labs A, B, and E), stomacher method (lab B), and Trichomatic 35 (labs C and D). T. pseudospiralis larvae were found in all 120 samples tested. For samples with 7 lpg, larval recoveries were significantly higher using the stomacher method versus the magnetic stirrer method, but there were no significant differences for samples with 17 lpg. In comparing laboratory results irrespective of the method used, lab B detected a significantly higher number of larvae than lab E for samples with 7 lpg, and lab E detected significantly less larvae than labs A, B, and D in samples with 17 lpg. The lowest overall variation for quantitative results (i.e. larval recoveries which were outside the tolerance range) was achieved by using the magnetic stirrer method (22%), followed by the stomacher method (25%), and Trichomatic 35 (30%). Results revealed that T. pseudospiralis larvae in samples with a nominal value of 7 and 17 lpg can be detected by all three methods of artificial digestion.

  5. Initial characterization of receptors for molecules that induce the settlement and metamorphosis of Haliotis rufescens larvae

    International Nuclear Information System (INIS)

    Trapido-Rosenthal, H.G.

    1985-01-01

    Larvae of the marine gastropod mollusc Haliotis refescens are induced to undergo metamorphosis by γ-aminobutyric acid (GABA) and stereochemically related compounds. The most potent of these inducers is (-)-β-(parachlorophenyl)-GABA (baclofen). The inductive response exhibits positive cooperatively, and is subject to both facilitation (up-regulation) and habituation (down-regulation). Facilitation is brought about by diamino acids such as L-diaminopropionic acid (L-DAPA), and is characterized by decreased Hill coefficients (n/sub H/) and concentration requirements (EC 50 ) for inducers. Facilitation does not require the simultaneous presence of facilitating and inducing compounds, and the facilitated state is persistent. Larvae are capable of being up-regulated 2 days before they are capable of undergoing settlement and metamorphosis. Habituation can be brought about by exposure of pre-competent larvae to GABA 4 days prior to the attainment of competence; it is then slowly reversible. Larvae specifically bind tritiated (-)-baclofen in a manner that is saturable with both increasing time of exposure of larvae to, and with increasing concentration of, this compound. Specific binding can be competed for by unlabeled GABA-mimetic inducing molecules; the order of effectiveness of these molecules as competitors for specific binding correlates well with their effectiveness as inducers of metamorphosis. Facilitation of larvae by exposure to diamino acids does not alter their specific binding of tritiated (-)-baclofen. It is concluded from these findings that Haliotis larvae possess receptors for GABA-mimetic compounds

  6. A comparison of honeybee (Apis mellifera) queen, worker and drone larvae by RNA-Seq.

    Science.gov (United States)

    He, Xu-Jiang; Jiang, Wu-Jun; Zhou, Mi; Barron, Andrew B; Zeng, Zhi-Jiang

    2017-11-06

    Honeybees (Apis mellifera) have haplodiploid sex determination: males develop from unfertilized eggs and females develop from fertilized ones. The differences in larval food also determine the development of females. Here we compared the total somatic gene expression profiles of 2-day and 4-day-old drone, queen and worker larvae by RNA-Seq. The results from a co-expression network analysis on all expressed genes showed that 2-day-old drone and worker larvae were closer in gene expression profiles than 2-day-old queen larvae. This indicated that for young larvae (2-day-old) environmental factors such as larval diet have a greater effect on gene expression profiles than ploidy or sex determination. Drones had the most distinct gene expression profiles at the 4-day larval stage, suggesting that haploidy, or sex dramatically affects the gene expression of honeybee larvae. Drone larvae showed fewer differences in gene expression profiles at the 2-day and 4-day time points than the worker and queen larval comparisons (598 against 1190 and 1181), suggesting a different pattern of gene expression regulation during the larval development of haploid males compared to diploid females. This study indicates that early in development the queen caste has the most distinct gene expression profile, perhaps reflecting the very rapid growth and morphological specialization of this caste compared to workers and drones. Later in development the haploid male drones have the most distinct gene expression profile, perhaps reflecting the influence of ploidy or sex determination on gene expression. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  7. A Determination of Metallothionein in Larvae of Freshwater Midges (Chironomus riparius Using Brdicka Reaction

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    Rene Kizek

    2008-07-01

    Full Text Available Among wide spectrum of biomolecules induced by various stress factors low molecular mass protein called metallothionein (MT is suitable for assessment of the heavy metal environmental pollution. The aim of this work was to determine the metallothionein and total thiols content in larvae of freshwater midges (Chironomus riparius sampled from laboratory exposure to cadmium(II ions and from field studies using differential pulse voltammetry Brdicka reaction. Unique electrochemical instrument, stationary electrochemical analyser Autolab coupled with autosampler, was utilized for the analysis of the samples. The detection limit for MT was evaluated as 5 nM. The larvae exposed to two doses (50 ng/g or 50 μg/g of cadmium(II ions for fifteen days under laboratory controlled conditions were at the end of the exposure killed, homogenized and analysed. MT content in control samples was 1.2 μM, in larvae exposed to 50 ng Cd/g it was 2.0 μM and in larvae exposed to 50 μg Cd/g 2.9 μM. Moreover at field study chironomid larvae as well as sediment samples have been collected from eight field sites with different levels of pollution by heavy. The metals content (chromium, nickel, copper, zinc, arsenic, molybdenum, cadmium, tin and lead in the sediment and or MT content in the chironomid larvae were determined by inductively coupled plasma mass spectrometry or Brdicka reaction, respectively.

  8. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae).

    Science.gov (United States)

    Macedo, Lilian Cristina; Melo, Francisco Tiago de Vasconcelos; Ávila-Pires, Teresa Cristina Sauer; Giese, Elane Guerreiro; dos Santos, Jeannie Nascimento

    2016-01-01

    Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the "Osvaldo Rodrigues da Cunha" Herpetology Collection of the Emílio Goeldi Museum, Belém, Pará, Brazil. The aim of this study was to present the morphological study of the Acanthocephala larvae found in A. ameiva ameiva lizard.

  9. A description of the Larva of Metapteron xanthomelas (Lucas, 1857) from the Restinga Forest of Southeastern Brazil (Coleoptera: Lycidae, Calopterini).

    Science.gov (United States)

    Ferreira, Vinicius De Souza; Costa, Cleide

    2015-02-03

    The last instar larva of Metapteron xanthomelas (Lucas, 1857) is described. This is the first description of a larva for the genus. Two live larvae collected in the Brazilian Atlantic coast Restinga Forest of Itanhaém, São Paulo, were reared, one to adult and one was fixed in the last instar. This larva differs from the known Calopterini larvae by the absence of urogomphi, the dorsal abdominal segments undivided and strongly alveolate ornamentation on the head. 

  10. Detecting mismatches in the phenology of cotton bollworm larvae and cotton flowering in response to climate change

    Science.gov (United States)

    Huang, Jian; Hao, HongFei

    2018-05-01

    Current evidence suggests that climate change has directly affected the phenology of many invertebrate species associated with agriculture. Such changes in phenology have the potential to cause temporal mismatches between predators and prey and may lead to a disruption in natural pest control ecosystem. Understanding the synchrony between pest insects and host plant responses to climate change is a key step to improve integrated pest management strategies. Cotton bollworm larvae damage cotton, and thus, data from Magaiti County, China, collected during the period of 1990-2015 were analyzed to assess the effects of climate change on cotton bollworm larvae and cotton flowering. The results showed that a warming climate advanced the phenology of cotton bollworm larvae and cotton flowering. However, the phenological rate of change was faster in cotton bollworm larvae than that in cotton flowering, and the larval period was prolonged, resulting in a great increase of the larval population. The abrupt phenological changes in cotton bollworm larvae occurred earlier than that in cotton, and the abrupt phenological changes in cotton flowering occurred earlier than that in larval abundance. However, the timing of abrupt changes in larval abundance all occurred later than that in temperature. Thus, the abrupt changes that occurred in larvae, cotton flowering and climate were asynchronous. The interval days between the cotton flowering date (CFD) and the half-amount larvae date (HLD) expanded by 3.41 and 4.41 days with a 1 °C increase of T mean in May and June, respectively. The asynchrony between cotton bollworm larvae and cotton flowering will likely broaden as the climate changes. The effective temperature in March and April and the end date of larvae (ED) were the primary factors affecting asynchrony.

  11. Detecting mismatches in the phenology of cotton bollworm larvae and cotton flowering in response to climate change.

    Science.gov (United States)

    Huang, Jian; Hao, HongFei

    2018-05-11

    Current evidence suggests that climate change has directly affected the phenology of many invertebrate species associated with agriculture. Such changes in phenology have the potential to cause temporal mismatches between predators and prey and may lead to a disruption in natural pest control ecosystem. Understanding the synchrony between pest insects and host plant responses to climate change is a key step to improve integrated pest management strategies. Cotton bollworm larvae damage cotton, and thus, data from Magaiti County, China, collected during the period of 1990-2015 were analyzed to assess the effects of climate change on cotton bollworm larvae and cotton flowering. The results showed that a warming climate advanced the phenology of cotton bollworm larvae and cotton flowering. However, the phenological rate of change was faster in cotton bollworm larvae than that in cotton flowering, and the larval period was prolonged, resulting in a great increase of the larval population. The abrupt phenological changes in cotton bollworm larvae occurred earlier than that in cotton, and the abrupt phenological changes in cotton flowering occurred earlier than that in larval abundance. However, the timing of abrupt changes in larval abundance all occurred later than that in temperature. Thus, the abrupt changes that occurred in larvae, cotton flowering and climate were asynchronous. The interval days between the cotton flowering date (CFD) and the half-amount larvae date (HLD) expanded by 3.41 and 4.41 days with a 1 °C increase of T mean in May and June, respectively. The asynchrony between cotton bollworm larvae and cotton flowering will likely broaden as the climate changes. The effective temperature in March and April and the end date of larvae (ED) were the primary factors affecting asynchrony.

  12. Carbohydrate digestion in Lutzomyia longipalpis' larvae (Diptera - Psychodidae).

    Science.gov (United States)

    Vale, Vladimir F; Moreira, Bruno H; Moraes, Caroline S; Pereira, Marcos H; Genta, Fernando A; Gontijo, Nelder F

    2012-10-01

    Lutzomyia longipalpis is the principal species of phlebotomine incriminated as vector of Leishmania infantum, the etiological agent of visceral leishmaniasis in the Americas. Despite its importance as vector, almost nothing related to the larval biology, especially about its digestive system has been published. The objective of the present study was to obtain an overview of carbohydrate digestion by the larvae. Taking in account that phlebotomine larvae live in the soil rich in decaying materials and microorganisms we searched principally for enzymes capable to hydrolyze carbohydrates present in this kind of substrate. The principal carbohydrases encountered in the midgut were partially characterized. One of them is a α-amylase present in the anterior midgut. It is probably involved with the digestion of glycogen, the reserve carbohydrate of fungi. Two other especially active enzymes were present in the posterior midgut, a membrane bound α-glucosidase and a membrane bound trehalase. The first, complete the digestion of glycogen and the other probably acts in the digestion of trehalose, a carbohydrate usually encountered in microorganisms undergoing hydric stress. In a screening done with the use of p-nitrophenyl-derived substrates other less active enzymes were also observed in the midgut. A general view of carbohydrate digestion in L. longipalpis was presented. Our results indicate that soil microorganisms appear to be the main source of nutrients for the larvae. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Enantiomerization and stereoselectivity in bioaccumulation of furalaxyl in Tenebrio molitor larvae.

    Science.gov (United States)

    Yin, Jing; Gao, Yongxin; Zhu, Feilong; Hao, Weiyu; Xu, Qi; Wang, Huili; Guo, Baoyuan

    2017-11-01

    Furalaxyl is a chiral pesticide and widely used in modern agriculture as racemate mixture. The enantiomerization and enantioselecive bioaccumulation by a single dose of furalaxyl to Tenebrio molitor larvae under laboratory conditions were studied using a high-performance liquid chromatography tandem mass spectroscopy method based on a ChiralPAK IC column. Our results showed that a significant enantiomerization (interconversion between R-enantiomer and S-enantiomer) was observed in Tenebrio molitor larvae under R- or S-furalaxyl exposure. Though the two furalaxyl enantiomers exhibited low-capacity of bioaccumulation in Tenebrio molitor larvae, bioaccumulation of rac-furalaxyl was enantioselective with a preferential accumulation of S-furalaxyl at 10mg/kg dosage exposure. In addition, enantiomerization and enantioselective degradation of the two enantiomers was not observed in wheat bran. These results showed that enantioselectivtiy of furalaxyl enantiomers was an important process combined with degradation, metabolism and enatiomerization in organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Effect of Vaccination with Irradiated Third Stage Larvae of Haemonchus Contortus

    International Nuclear Information System (INIS)

    Beriajaya; Sukardji, P.

    2000-01-01

    The objective of this study was to determine the effect of vaccination with irradiated third stage larvae of Haemonchus contortus on immune responses in sheep. A number of 15 young male thin-tail sheep freed of worms were divided into 3 groups of 5. The first group was vaccinated with 50.000 irradiated third larvae of H. contortus . The second group was vaccinated as group 1 but without challenged. The third group was not vaccinated but challenged as group 1. Observations were carried out on egg counts, worn counts, total serum protein and antibody titer against H. contortus. The results showed there was no significant differences (P>0.05) on egg counts, worn counts and antibody titer, but a significant difference was seen on value of serum protein between vaccinated group and non vaccinated group. The results showed no protective immunity which is showed in worn counts of vaccinated and non vaccinated groups. Key word: Haemonchus contortus, irradiated larvae, sheep, vaccine

  15. The effects of drilling muds on marine invertebrate larvae and adults

    International Nuclear Information System (INIS)

    Raimondi, P.T.; Barnett, A.M.; Krause, P.R.

    1997-01-01

    A series of laboratory experiments tested the effects of drilling muds from an active platform off southern California on larvae and adults of marine invertebrates. Red abalone (Haliotis rufescens) were used to determine effects of drilling muds on fertilization, early development, survivorship, and settlement, and experiments on adult brown cup corals (Paracyathus stearnsii) tested effects on adult survivorship, viability, and tissue loss. Exposures to drilling muds did not have an effect on abalone fertilization or early development. However, several exposures to drilling muds resulted in weak, but significant, positive effects of drilling muds on settlement of competent larvae. In contrast, settlement of red abalone larvae on natural coralline algal crusts decreased with increasing concentrations of drilling muds. This suggests that drilling muds affect either the abalone's ability to detect natural settlement inducers, or they affect the inducer itself. Exposure of brown cup corals to concentrations of drilling muds adversely impacted their survivorship and viability. These effects were likely caused by increased tissue mortality of the coral polyps

  16. PEMELIHARAAN LARVA IKAN KLOWN (Amphiprion percula DENGAN PAKAN ALAMI YANG BERBEDA

    Directory of Open Access Journals (Sweden)

    Ketut Maha Setiawati

    2016-11-01

    Full Text Available Nilai jual ikan hias klown sangat tergantung dari kecerahan dan keunikan warna yang dimilikinya, namun ikan hias produk hatcheri masih belum sebaik hasil tangkapan alam. Pengkayaan dengan bahan komersial dan Nannochloropsis sp. pada rotifer dan Artemia sebagai pakan alami tidak mampu meningkatkan kecerahan warna benih ikan. Oleh sebab itu, diperlukan pakan alami lain yang mampu meningkatkan kecerahan warna. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian rotifer dan copepod terhadap performan warna benih ikan klown, serta pertumbuhan dan sintasan yang dihasilkan. Penelitian dilakukan dengan menggunakan wadah bak fiber volume 200 L yang diisi air laut sebanyak 150 L. Telur ikan klown yang telah berumur enam hari ditebar sebanyak 200 butir/bak. Perlakuan berupa pemberian pakan alami: (A rotifer dan (B rotifer + copepod yang masing-masing mempunyai lima ulangan. Pemberian pakan perlakuan dilakukan sampai larva berumur 30 hari. Selain pakan perlakuan, mulai hari ke-20 juga ditambahkan pakan buatan berupa pakan mikro pada semua larva. Hasil penelitian menunjukkan bahwa, tambahan copepod sebagai pakan alami pada pemeliharaan larva ikan klown dapat meningkatkan kecerahan warna. Selain itu, panjang total dan bobot badan larva pada hari ke-20 untuk perlakuan B adalah masingmasing 10,44 ± 0,24 mm dan 15,2 ± 0,5 mg lebih baik daripada perlakuan A yaitu 9,15 ± 1,27 mm dan 9,2 ± 0,1 mg. Demikian pula vitalitas benih yang dihasilkan, menunjukkan bahwa ikan pada perlakuan B lebih kuat dibandingkan perlakuan A. Benih ikan pada perlakuan B tahan selama 231,6 detik dalam air tawar sedangkan pada perlakuan A hanya selama 39,8 detik. Price of ornamental fish highly depends on the brightness and unique appearance of its color. While of ornamental fish bred in hatcheries are less attractive in appearance compared to the wild ones. Enrichment of live feed i.e rotifer and Artemia using commercial enrichment and Nannochloropsis sp. was not able to

  17. Contenido de los nutrientes básicos en Catolaccus grandis Burks criados sobre larvas del picudo del algodon Basic nutrients content of Catolaccus grandis Burks reared in cotton boll weevil larvae

    Directory of Open Access Journals (Sweden)

    LÚCIA HELENA AVELINO ARAUJO

    2000-09-01

    Full Text Available El objetivo del trabajo fue determinar los niveles de carbohidratos, proteínas solubles y aminoácidos libres de larvas, pupas hembras y adultos hembras de Catolaccus grandis (Burks (Hymenoptera: Pteromalidae criados sobre larvas del picudo del algodón envenenadas por hembras del parasitoide y por larvas de primer instar del parasitoide. Esto estudio fue conducido en la Unidade de Investigación de Control Biologico de Plagas del Departamento de Agricultura de los Estados Unidos de la América, en Weslaco, Texas. Las 20 muestras de cada uno de los tres estados de desarrollo: tercer instar larval, pupas hembra y adultos hembra del parasitoide C. grandis, fueron separadas y pesadas individualmente y se cuantió el contenido de carbohidratos totales, proteínas solubles totales y aminoácidos libres criados en diferentes sustratos. Los resultados obtenidos confirman la existencia de patrones metabólicos significativamente distintos de estos nutrientes básicos.The aim of this work was to determine the levels of carbohydrate, soluble proteins and free amino acids of larvae, pupae and adult females Catolaccus grandis Burks (Hymenoptera: Pteromalidae which were reared in cotton (Gossypium hirsutum L. r. latifolium Hutch boll weevil (Anthonomus grandis larvae venomized by ectoparasitoid of female and 1st instar ectoparasitoid larvae. This study was carried out at the Biological Control of Pests Research Unit, Weslaco, Texas. The twenty samples of each one of three stages of development: 3rd instar larval, female pupae and female adult of parasitoid C. grandis were separated and individually weighted, and levels of carbohydrates, proteins and amino acids were quantified when reared in different substrates. The results confirmed the existence of metabolic patterns significantly distinct from the basic nutrient model.

  18. EFFICIENCY OF INSECTICIDES IN LARVAE AND ADULTS CONTROL OF CITRUS ROOT WEEVILS EFICIÊNCIA DE INSETICIDAS NO CONTROLE DE LARVAS E ADULTOS DE CURCULIONÍDEOS-DAS-RAÍZES EM CITROS

    Directory of Open Access Journals (Sweden)

    Felipe Sulzbach

    2007-09-01

    Full Text Available

    The control of larvae and adults of citrus root weevils (Naupactus spp. was evaluated in four experiments, in field and laboratory conditions, at Itapetininga, São Paulo State, Brazil. For larvae control of Naupactus spp. the insecticides tested were: aldicarb, bifenthrin, carbofuran, carbosulfan, chlorpyrifos (GR, chlorpyrifos (EW, fipronil, imidacloprid, and thiamethoxam (GR. For adults control of Naupactus cervinus and N. versatilis the following products were tested: abamectin, carbosulfan. lufenuron, lufenuron + abamectin, and thiamethoxam (WG. The efficiency control of Naupactus spp. larvae was below 80%, for all treatments tested (insecticides, dosages, and application methods. On larvae, the best results were obtained with thiamethoxam (GR 2.40 g, fipronil 0.19 g, and thiamethoxam (WG 1.00 g of a.i.plant-1, with 71.43%, 74.12% and 77.87% larvae population reduction, respectively. For N. cervinus and N. versatilis adults control, thiamethoxam (WG with 0.75 g and 1.00 g, and carbosulfan with 0.64 g of a.i. planta-1 showed efficiency above 80% in the field tests. While in the laboratory test, besides these treatments, also tiamethoxam (WG with 0.5 g of a.i. plant-1 presented such efficiency. The adult mortality was similar between the studied species. Thiamethoxam (WG and carbosulfan may be reccommended for adults of this insect.

    KEY-WORDS: Insect pest; Naupactini; chemical control.

    O controle de larvas e adultos de curculionídeos-das-raízes foi avaliado em quatro experimentos, em condições de  laboratório e de campo, no município de Itapetininga, SP. Para o controle de larvas de Naupactus spp. foram testados os inseticidas: aldicarbe, bifentrina, carbofurano, carbosulfano, clorpirifós (GR, clorpirifós (EW, fipronil, imidacloprido e tiametoxam (GR. Para o

  19. Comparative susceptibility of veliger larvae of four bivalve mollusks to a Vibrio alginolyticus strain.

    Science.gov (United States)

    Luna-González, A; Maeda-Martínez, A N; Sainz, J C; Ascencio-Valle, F

    2002-06-03

    The susceptibility of 7 d old veliger larvae of the scallops Argopecten ventricosus and Nodipecten subnodosus, the penshell Atrina maura, and the Pacific oyster Crassostrea gigas to a pathogenic strain of Vibrio alginolyticus was investigated by challenging the larvae with different bacterial concentrations in a semi-static assay. The results indicate that the larvae of the 2 scallop species are more susceptible to the V. alginolyticus strain than those of the oyster and the penshell. Signs of the disease were similar to bacillary necrosis described in previous work. Interspecies differences in susceptibility to pathogens are discussed.

  20. Effect of Different Substrates on the Acceptance of Grafted Larvae in Commercial Honey Bee (Apis Mellifera Queen Rearing

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    Contreras-Martinez Celia A.

    2017-12-01

    Full Text Available The need for the increased production of honey bee (Apis mellifera queens has led beekeepers to use different substrates in artificial queen cups where larvae destined to become queens are deposited (grafting. However, not enough scientific evidence exists that indicates that this practice is useful and what substance offers the best results. This study was conducted to determine with the Doolittle queen rearing method the acceptance rate of larvae deposited on different substrates during grafting and to determine if the sugar content and pH of the substrates used affect the acceptance of larvae in cell builder colonies. The evaluated substrates were coconut water, apple nectar, royal jelly, cola soda and distilled water, plus control (without substrate. Grafted larvae of the six treatments were introduced into cell builder colonies and their acceptance verified after 72 h. Apple nectar provided the highest rate of larvae acceptance with 81.06%, followed by cola soda with 62.93%, coconut water with 60.90%, royal jelly with 57.82% and distilled water with 58.99%. The larvae acceptance rates of all substrates were significantly higher than the control, which had an acceptance rate of 47.04%. No significant relationship was found between the sugar content of the substrates and larvae acceptance. However, although not significant, a high negative correlation was found between the substrate pH and the number of accepted larvae (Rho = - 0.90, p = 0.07. These results suggest that the use of liquid acidic substrates during larvae grafting, in particular apple nectar, may increase the production of honey bee queens.