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Sample records for larvae food uptake

  1. 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.

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

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    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.

  3. 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.

  4. Uptake of Iodide From Water in Atlantic Halibut Larvae (Hippoglossus Hippoglossus L.)

    DEFF Research Database (Denmark)

    Moren, Mari; Sloth, Jens Jørgen; Hamre, Kristin

    2008-01-01

    The natural diet of marine fish larvae, copepods, contain 60-350 mg I kg(-1), while live feed used in commercial hatcheries have iodine concentrations in the range of 1 mg kg(-1). Seawater is also considered to be an important source of iodine for marine fish. The question asked in this study is ......M. The uptake was partly blocked by perchlorate (ClO3-) which is a known inhibitor of the sodium iodide symporter. This indicates that the Atlantic halibut larvae accumulate iodide through both specific and non-specific uptake pathways....

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

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    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.

  6. Chironomidae bloodworms larvae as aquatic amphibian food.

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    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.

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

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    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.

  8. Partitioning of oxygen uptake between the gills and skin in fish larvae: a novel method for estimating cutaneous oxygen uptake.

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    Rombough, P J

    1998-06-01

    The goal of this study was to develop an alternative to the traditional rubber dam method for measuring cutaneous oxygen uptake in bimodally respiring (skin + gills) fish larvae. The method tested involved using microelectrodes to measure the PO2 gradient in the diffusive boundary layer adjacent to seven positions on the skin surface (one on the head, two on the yolk sac, two on the trunk, one at the base of the dorsal fin-fold and one on the proximal portion of the caudal fin-fold) of rainbow trout (Oncorhynchus mykiss) larvae in still water. The PO2 gradient (deltaPO2/delta x, where x is the distance from the skin surface) was then used to calculate area-specific rate of O2 uptake (.MO2/A) according to the Fick equation, .MO2/A=Dbeta(deltaPO2/deltax), where A is the cross-sectional area of the boundary layer, D is the diffusion coefficient and beta is the capacitance coefficient for O2 in water. The accuracy of the method was assessed by comparing it with the rubber dam method. After correcting for differences in body mass, the two methods gave essentially identical results. According to the boundary layer method, the mean (+/-95 % CI) rate of O2 uptake across the skin of newly hatched rainbow trout at 10 degrees C is 3.13+/-0.18 microg O2 cm-2h-1 (N=265). The corresponding value obtained using the rubber dam method was 3. 36+/-0.35 microg O2 cm-2 h-1 (N=27). The advantages of the boundary layer method are that it can be used with smaller, more delicate larvae and that variables, such as flow rate, that can affect the efficiency of gas exchange can be regulated more precisely. The boundary layer method also permits examination of regional differences in exchange efficiency, although in still water such differences do not appear to be significant in trout larvae. The mean steepness of the PO2 gradient in the boundary layer and, hence, the mean rate of area-specific O2 uptake were essentially the same (P>0.05) at all seven locations tested in this study. The

  9. Food restriction alters energy allocation strategy during growth in tobacco hornworms (Manduca sexta larvae).

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    Jiao, Lihong; Amunugama, Kaushalya; Hayes, Matthew B; Jennings, Michael; Domingo, Azriel; Hou, Chen

    2015-08-01

    Growing animals must alter their energy budget in the face of environmental changes and prioritize the energy allocation to metabolism for life-sustaining requirements and energy deposition in new biomass growth. We hypothesize that when food availability is low, larvae of holometabolic insects with a short development stage (relative to the low food availability period) prioritize biomass growth at the expense of metabolism. Driven by this hypothesis, we develop a simple theoretical model, based on conservation of energy and allometric scaling laws, for understanding the dynamic energy budget of growing larvae under food restriction. We test the hypothesis by manipulative experiments on fifth instar hornworms at three temperatures. At each temperature, food restriction increases the scaling power of growth rate but decreases that of metabolic rate, as predicted by the hypothesis. During the fifth instar, the energy budgets of larvae change dynamically. The free-feeding larvae slightly decrease the energy allocated to growth as body mass increases and increase the energy allocated to life sustaining. The opposite trends were observed in food restricted larvae, indicating the predicted prioritization in the energy budget under food restriction. We compare the energy budgets of a few endothermic and ectothermic species and discuss how different life histories lead to the differences in the energy budgets under food restriction.

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

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    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.

  11. Bioaccumulation of arsenic and silver by the caddisfly larvae Hydropsyche siltalai and H. pellucidula

    DEFF Research Database (Denmark)

    Awrahman, Zmnako; Rainbow, Philip S; Smith, Brian D

    2015-01-01

    Biodynamic modeling was used to investigate the uptake and bioaccumulation of arsenic and silver from water and food by two Hydropsychid caddisfly larvae: Hydropsyche siltalai and Hydropsyche pellucidula. Radiotracer techniques determined the uptake rate constants of arsenic and silver from water...... solution were significantly lower than those of As and Ag assimilated from ingested food in both species. Experimentally derived ku and ke values were then used to predict As and Ag tissue concentrations in hydropsychids collected from 13 UK sites, including metal-contaminated streams in Cornwall. Arsenic...

  12. Inorganic nutrients in natural and artificial food of Dacus oleae larvae (Diptera: Tephritidae)

    International Nuclear Information System (INIS)

    Manoukas, A.G.; Grimanis, A.; Mazomenos, B.

    1978-01-01

    Certain inorganic nutrients contained in the natural and artificial food of Dacus oleae larvae were determined by neutron activation analysis and spectrophotometry. The content of sodium, potassium, calcium, magnesium, manganese, iron, zinc, copper and phosporus was reported for the olive fruit mesocarp at three stages of maturity, brewer's yeast, soybean hydrolysate and roasted peanuts. Several differences were found between the inorganic nutrient content of the natural food (olive fruit) and artificial diet of D. oleae larvae. The differences which may be important in the nutrition and metabolism of this insect were estimated and discussed

  13. Uptake of heavy metals and arsenic in black soldier fly (Hermetia illucens) larvae grown on seaweed-enriched media.

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

    2018-04-01

    The black soldier fly (Hermetia illucens) is one of the most promising insect species for use in animal feed. However, studies investigating feed and food safety aspects of using black soldier fly as feed are scarce. In this study, we fed black soldier fly larvae feeding media enriched with seaweed, which contains naturally high concentrations of heavy metals and arsenic. The aim of this study was to investigate the potential transfer of such undesirable substances from the feeding media to the larvae. The larvae accumulated cadmium, lead, mercury and arsenic. Concentrations of these elements in the larvae increased when more seaweed was added to the feeding media. The highest retention was seen for cadmium (up to 93%) and the lowest for total arsenic (up to 22%). When seaweed inclusion exceeded 20% in the media, this resulted in larval concentrations of cadmium and total arsenic above the current European Union maximum levels for these elements in complete feed. Our results confirm that insect larvae can accumulate heavy metals and arsenic when present in the feeding media. A broader understanding of the occurrence of these undesirable substances in processed larvae products is needed to assess feed and food safety. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Estimation of food limitation of bivalve larvae in coastal waters of north-western Europe

    DEFF Research Database (Denmark)

    Bos, O.G.; Hendriks, I.E.; Strasser, M.

    2006-01-01

    Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made...... assimilation rate averaged 7-26% of the maximum assimilation rate. Under the assumptions made for the present study, it is suggested that growth of larvae in north-west European waters is often food-limited. (c) 2005 Elsevier B.V. All rights reserved...

  15. Food and feeding ecology of Brazilian sardine (Sardinella brasiliensis larvae from the southeastern Brazilian Bight

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    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

  16. Replacing of live food with artificial diet on growth and survival rates of white leg shrimp (Litopenaeus vannamei) larvae

    OpenAIRE

    Ghorbani Vagheie, R.; Matinfar, A.; Aeinjamshid, Kh.; Hafezieh, M.; Ghorbani, R.

    2011-01-01

    Replacing live food with artificial diets in aquatic larviculture, especially in shrimp larvae not only is caused convenience feeding, but also in economical view is very important. With this object, in this survey, a density of 100.L -1 white leg shrimp larvae in 9 nutritional treatments each with three replicates were cultured in 20L tanks each one was held with 10L of 30% salty water using one air stone. The larvae were fed 4 times.day-1 with different diets, including live foods (Cheatoce...

  17. The uptake of 14C-glycine to Bufo vulgaris formosus (Boulenger) larva at metamorphosis

    International Nuclear Information System (INIS)

    Hasegawa, Hitoshi; Tanaka, Haruo; Ishiguro, Shigeru; Nonoyama, Kiyoshi; Nakagawa, Harumi.

    1981-01-01

    With the eggs of Bufo vulgaris formosus (Boulenger) immediately after fertilization, the larvae in the 50 ml solution containing 1 ml of 14 C-glycine were developed to the end of metamorphosis. Measurements were made on the length of body, tail, fore limb and hind leg through the stages of tail degeneration and vestige. The radioactivity of the cut off fore limbs, hind legs, tails and head trunks was measured with a scintillation counter, and the 10 μ sections of the samples were used for autoradiography. The larvae uptook orally 14 C-glycine to the organs of cell tissues. On the basis of the reports of the autolysis of tails and the activation of lysosome enzyme in metamorphosis and on the uptake of 14 C-leucine and 14 C-proline to four legs by other workers, and on the present results, the free amino acids formed from the autolysis of tails were utilized for the recomposition of organ protein synthesis in the metamorphosis of the amphibians. (J.P.N.)

  18. Relationship between digestive enzymes and food habit of Lutzomyia longipalpis (Diptera: Psychodidae) larvae: Characterization of carbohydrases and digestion of microorganisms.

    Science.gov (United States)

    Moraes, C S; Lucena, S A; Moreira, B H S; Brazil, R P; Gontijo, N F; Genta, F A

    2012-08-01

    The sandfly Lutzomyia longipalpis (Lutz and Neiva, 1912) is the main vector of American Visceral Leishmaniasis. In spite of its medical importance and several studies concerning adult digestive physiology, biochemistry and molecular biology, very few studies have been carried out to elucidate the digestion in sandfly larvae. Even the breeding sites and food sources of these animals in the field are largely uncharacterized. In this paper, we describe and characterize several carbohydrases from the gut of L. longipalpis larvae, and show that they are probably not acquired from food. The enzyme profile of this insect is consistent with the digestion of fungal and bacterial cells, which were proved to be ingested by larvae under laboratory conditions. In this respect, sandfly larvae might have a detritivore habit in nature, being able to exploit microorganisms usually encountered in the detritus as a food source. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Survival Rate and Growth of Fighting Fish Larvae (Betta splendens Regan Fed on Various Live Foods

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    T. Budiardi

    2007-01-01

    Full Text Available Larval of fighting fish (Betta splendens Regan requires precise live foods for its growth and survival. In this experiment, fish larvae were fed on either Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, or Paramecium + Moina + Tubifex. The fish were fed Paramecium from day-2 till day-7 after hatching. There after, the live food was changed according to the treatments till day-28.  Results showed that fish fed on Paramecium + Artemia significantly had the highest total length (12.63 mm than other treatments (11.86 mm. On the other hand, survival rate of fish had no significant affected by the treatments. Keywords: fighting fish, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larvae   ABSTRAK Larva ikan betta (Betta splendens Regan membutuhkan jenis pakan alami yang tepat bagi kelangsungan hidup dan pertumbuhannya. Pada penelitian ini, larva ikan diberi pakan berupa Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, atau Paramecium + Moina + Tubifex.  Ikan diberi pakan pakan berupa Paramecium dari hari ke-2 hingga hari ke-7. Setelah itu, pemberian pakan alami diubah berdasarkan masing-masing perlakuan hingga hari ke-28.  Hasil penelitian menunjukkan bahwa ikan yang diberi pakan Paramecium + Artemia memiliki tubuh secara signifikan lebih panjang (12,63 mm dibandingkan perlakuan lainnya (11,86 mm.  Sementara itu, kelangsungan hidup tidak dipengatuhi oleh perlakuan. Kata kunci: ikan betta, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larva

  20. Food consumption by Chilo partellus (Lepidoptera: Pyralidae) larvae infected with Beauveria bassiana and Metarhizium anisopliae and effects of feeding natural versus artificial diets on mortality and mycosis.

    Science.gov (United States)

    Tefera, Tadele; Pringle, K L

    2003-11-01

    Second and third instar Chilo partellus larvae were infected with Beauveria bassiana and Metarhizium anisopliae (both at 1x10(8)conidia/ml) and daily consumption of maize leaves was measured. Infection by the fungi was associated with reduced mean daily food consumption. Reduction in food consumption became evident 3-4 days after treatment with the fungi for second instar larvae and 4-5 days for third instar larvae. Four conidial concentrations, 1x10(5), 1x10(6), 1x10(7), and 1x10(8)conidia/ml, were tested against second instar larvae. Food consumption dropped by 70-85% when the second instar larvae were treated with the fungi at 1x10(8)conidia/ml. Reduction in food consumption by C. partellus larvae infected with B. bassiana and M. anisopliae may offset the slow speed of kill of the fungi. The effect of artificial versus natural diets on mortality and mycoses of second instar larvae treated with the fungi at 1x10(8)conidia/ml was determined. Larvae provided with artificial diet suffered little mortality and mycoses than larvae provided with maize leaves. The LT(50) was longer for larvae provided with artificial diet.

  1. Occupational allergy to aquarium fish food: red midge larva, freshwater shrimp, and earthworm. A clinical and immunological study.

    Science.gov (United States)

    Meseguer Arce, J; Villajos, I M Sánchez-Guerrero; Iraola, V; Carnés, J; Fernández Caldas, E

    2013-01-01

    Chironomids seem to be the main cause of occupational allergy to aquarium fish food. The aim of this study was to investigate the pattern of occupational sensitization to 3 different arthropod species used as components of aquarium fish food. The study sample comprised 8 workers from a fish food packing department. The control group comprised 40 atopic patients (20 of whom were allergic to mites). We performed prick tests with extracts of red midge larva (Chironomus thummi), freshwater shrimp (Gammarus species), earthworm (Tubifex species), and other arthropod species and a battery of common inhalant allergens. We measured peak expiratory flow rate (PEFR) and specific immunoglobulin (Ig) E and performed a methacholine challenge test, nasal challenge test, and immunoblotting. Cross-reactivity analyses were completed using immunoblotting and CAP inhibition. Prick test results were positive to red midge larvae in 7 patients (87.5%), Gammarus in 5 (62.5%), Tubifex in 3 (37.5%), and mites in 6 (75%). In the mite-allergic controls, 30% had positive prick test results to red midge larvae. PEFR decreased > or = 20% during the packing process in all patients, and in 1 patient it indicated a dual asthmatic response. Methacholine challenge test results were positive in all participants. Nasal challenge tests were performed in 4 patients, and the results were positive. Specific IgE to red midge larvae was detected in 62.5%, Gammarus in 50%, and Tubifex in 16%. Bands of approximately 14-15 kDa and 31 kDa were observed in Gammarus and red midge larvae extracts. Cross-reactivity assays demonstrated that Gammarus totally inhibited red midge larvae, while Tubifex did so partially. Dermatophagoides pteronyssinus showed very low inhibitory capacity. Aquarium fish food arthropods are potent allergens with an elevated prevalence of sensitization and variable degree of crossreactivity. This is the first report of occupational allergy to Tubifex. More data are necessary to identify and

  2. The influence of food supply on the response of Olympia oyster larvae to ocean acidification

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    A. Hettinger

    2013-10-01

    Full Text Available Increases in atmospheric carbon dioxide drive accompanying changes in the marine carbonate system as carbon dioxide (CO2 enters seawater and alters ocean pH (termed "ocean acidification". However, such changes do not occur in isolation, and other environmental factors have the potential to modulate the consequences of altered ocean chemistry. Given that physiological mechanisms used by organisms to confront acidification can be energetically costly, we explored the potential for food supply to influence the response of Olympia oyster (Ostrea lurida larvae to ocean acidification. In laboratory experiments, we reared oyster larvae under a factorial combination of pCO2 and food level. Elevated pCO2 had negative effects on larval growth, total dry weight, and metamorphic success, but high food availability partially offset these influences. The combination of elevated pCO2 and low food availability led to the greatest reduction in larval performance. However, the effects of food and pCO2 interacted additively rather than synergistically, indicating that they operated independently. Despite the potential for abundant resources to counteract the consequences of ocean acidification, impacts were never completely negated, suggesting that even under conditions of enhanced primary production and elevated food availability, impacts of ocean acidification may still accrue in some consumers.

  3. The influence of synthetic food additives and surfactants on the body weight of larvae of Tenebrio molitor (Coleoptera, Tenebrionidae

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    V. O. Martynov

    2017-08-01

    Full Text Available The broad spectrum of negative effects of food additives and surfactants on living organisms and the environment in general indicate a necessity of a detailed study on this issue. The aim of this article is to evaluate the impact of food additives and surfactants in a concentration of 350 mg/kg of fodder on the body weight of third age Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae larvae. A significant change in the body weight of T. molitor larvae was observed when they consumed a diet containing 350 mg/kg of sodium glutamate, sodium cyclamate and sodium benzoate. We observed a tendency towards increase in body weight after addition of the food colouring Allura Red, saccharin, benzoic acid, betaine, emulsifying wax, AOS and SLES, and also we observed a decrease in body weight after addition of Tartrazine and Indigo Carmine in the same concentration. Out of the 18 tested food additives, 3 significantly stimulated an increase in the body weight of third age T. molitor larvae, and 3 manifested the same effect at the level of tendency (stimulated an increase in mass on average by 43–58% over the 14-day experiment, and 2 caused decrease in the body weight of larvae. Also, the 4 studied surfactants manifested a tendency towards increase in the body weight of T. molitor. This study on the impact of food additives and surfactants on organisms of insects is of great significance for protecting rare species of insects.

  4. Self mixing of fly larvae during feeding

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    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.

  5. Influence of food diet in the radiosensitivity of spodoptera frugiperda smith abbot larvae

    International Nuclear Information System (INIS)

    Gonzalez, M.; Labrada, A.; Fundora, Z.; Herrera, A.

    1988-01-01

    To apply the traditional method in pest control it is needed to know the reaction capability of the insect in reference to radiations as well as the influence which can be exerted over it by different factors. The radiosensitivity of Spodoptera Frugiperda Smith Abbot larvae raised with two different diets (natural and artificial) was studied using doses between 20 and 100 Gy, in Co-60 gamma source with a dose power of 13.4 Gy/min survival, formation and dimensions of pupas, adult emergency and other interesting aspects were determined. The multiple analysis of results showed the influence of the food diet on radiosensitivity of larvae. results of both diets are statistically compared

  6. Species-specific modulation of food-search behavior by respiration and chemosensation in Drosophila larvae.

    Science.gov (United States)

    Kim, Daeyeon; Alvarez, Mar; Lechuga, Laura M; Louis, Matthieu

    2017-09-05

    Animals explore their environment to encounter suitable food resources. Despite its vital importance, this behavior puts individuals at risk by consuming limited internal energy during locomotion. We have developed a novel assay to investigate how food-search behavior is organized in Drosophila melanogaster larvae dwelling in hydrogels mimicking their natural habitat. We define three main behavioral modes: resting at the gel's surface, digging while feeding near the surface, and apneic dives. In unstimulated conditions, larvae spend most of their time digging. By contrast, deep and long exploratory dives are promoted by olfactory stimulations. Hypoxia and chemical repellents impair diving. We report remarkable differences in the dig-and-dive behavior of D. melanogaster and the fruit-pest D. suzukii . The present paradigm offers an opportunity to study how sensory and physiological cues are integrated to balance the limitations of dwelling in imperfect environmental conditions and the risks associated with searching for potentially more favorable conditions.

  7. Laboratory investigation of daily food intake and gut evacuation in larvae of African catfish Clarias gariepinus under different feeding conditions

    NARCIS (Netherlands)

    García-Ortega, A.; Verreth, J.A.J.; Vermis, K.; Nelis, H.J.; Sorgeloos, P.; Verstegen, M.W.A.

    2010-01-01

    Abstract Temporary accumulation of ascorbic acid 2-sulfate (AAS) was measured to estimate food intake and gut evacuation in larvae of African catfish. Fish larvae were fed decapsulated cysts of Artemia containing AAS. In a first experiment it was found that no biosynthesis of AAS occurs in the

  8. General odorant-binding proteins and sex pheromone guide larvae of Plutella xylostella to better food.

    Science.gov (United States)

    Zhu, Jiao; Ban, Liping; Song, Li-Mei; Liu, Yang; Pelosi, Paolo; Wang, Guirong

    2016-05-01

    Olfaction of Lepidopteran larvae has received little attention, compared to the damage to crops done by insects at this stage. We report that larvae of the diamondback moth Plutella xylostella are attracted to their natural sex pheromone and to their major component (Z)-11-hexadecenal, but only in a food context. For such task they use two general odorant-binding proteins (GOBPs), abundantly expressed in the three major sensilla basiconica of the larval antenna, as shown by whole-mount immunostaining and immunocytochemistry experiments. None of the three genes encoding pheromone-binding proteins (PBPs) are expressed at this stage. Both recombinant GOBPs bind (Z)-11-hexadecenal and the corresponding alcohol, but not the acetate. Binding experiments performed with five mutants of GOBP2, where aromatic residues in the binding pocket were replaced with leucine showed that only one or two amino acid substitutions can completely abolish binding to the pheromone shifting the affinity to plant-derived compounds. We hypothesise that detection of their species-specific pheromone may direct larvae to the sites of foraging chosen by their mother when laying eggs, to find better food, as well as to reduce competition with individuals of the same or other species sharing the same host plant. We also provide evidence that GOBP2 is a narrowly tuned binding protein, whose affinity can be easily switched from linear pheromones to branched plants terpenoids, representing a tool better suited for the simple olfactory system of larvae, as compared to the more sophisticated organ of adults. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Carbon and nitrogen stable isotope ratios analysis of food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) in strongly acidic lake Katanuma

    International Nuclear Information System (INIS)

    Doi, Hideyuki; Kikuchi, Eisuke; Shikano, Shuichi

    2001-01-01

    The food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) were analyzed using carbon and nitrogen stable isotope ratios in Lake Katanuma. Lake Katanuma is a volcanic and strongly acidic lake (average pH 2.2). In Lake Katanuma, potential sources of diets for the chironomid larvae are limited including a benthic diatom (Pinnularia braunii), a phytoplankton (Chlamydomonas acidophila), sulfate oxidizing bacteria, and vascular plants supplied from vegetation surrounding the lake. Based on the average carbon and nitrogen isotope ratios among these potential sources and sediment, benthic diatoms were considered to be most probable food source of the chironomid larvae. δ 13 C values of the chironomid were significantly different among seasons and habitat depths, suggesting that diet of C. acerbiphilus changed seasonally and with habitat depth. (author)

  10. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae.

    Science.gov (United States)

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    2016-01-01

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on the impact of nano-sized plastics on marine organisms. Therefore, the present study aims to evaluate the effects of 40nm anionic carboxylated (PS-COOH) and 50nm cationic amino (PS-NH2) polystyrene nanoparticles (PS NPs) on brine shrimp Artemia franciscana larvae. No signs of mortality were observed at 48h of exposure for both PS NPs at naplius stage but several sub-lethal effects were evident. PS-COOH (5-100μg/ml) resulted massively sequestered inside the gut lumen of larvae (48h) probably limiting food intake. Some of them were lately excreted as fecal pellets but not a full release was observed. Likewise, PS-NH2 (5-100µg/ml) accumulated in larvae (48h) but also adsorbed at the surface of sensorial antennules and appendages probably hampering larvae motility. In addition, larvae exposed to PS-NH2 undergo multiple molting events during 48h of exposure compared to controls. The activation of a defense mechanism based on a physiological process able to release toxic cationic NPs (PS-NH2) from the body can be hypothesized. The general observed accumulation of PS NPs within the gut during the 48h of exposure indicates a continuous bioavailability of nano-sized PS for planktonic species as well as a potential transfer along the trophic web. Therefore, nano-sized PS might be able to impair food uptake (feeding), behavior (motility) and physiology (multiple molting) of brine shrimp larvae with consequences not only at organism and population level but on the overall ecosystem based on the key role of zooplankton on marine food webs. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Effect of food type and concentration on growth and fatty acid composition of early larvae of the anchovy (Engraulis encrasicolus) reared under laboratory conditions

    KAUST Repository

    Garrido, Susana

    2012-12-01

    Experiments were conducted during the summer of 2008 and 2009 to study the growth of early post yolk-sac European anchovy (Engraulis encrasicolus, Linnaeus, 1758) larvae reared under different food regimes. The fatty acid composition was used to assess nutritional condition of the larvae. Prey items used in the experiments were Gymnodinium sanguineum, Brachionus plicatilis and nauplii of the copepods Acartia grani and Euterpina acutifrons. Food type and concentration affected the growth of the larvae. Mixed diets composed of rotifers and copepod nauplii at high concentration resulted in higher anchovy larvae growth rates in comparison with single-prey diets using either rotifers or copepod nauplii. The addition of the dinoflagellate G. sanguineum (25-50cellsml -1) to the prey offered did not enhance significantly larval growth. Highest growth rates of anchovy larvae (0.28mmd -1) were obtained using high concentrations of a mixed diet, particularly the combination of rotifers and A. grani nauplii. Fatty acid composition at hatch was similar to the composition observed in the field, but during larvae ontogeny there was a marked decrease in the contribution of polyunsaturated fatty acids such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Such difference reflects the high requirements of these PUFA for larvae development, and suggests that the food offered failed to fulfill the larvae nutritional requirements. The growth rates obtained in our experiments were, overall, in the lower range of those observed in natural conditions. Taking into considerations the fact that larvae in the field are expected to encounter lower prey concentrations, we discuss the reasons for such disagreement. © 2012 Elsevier B.V.

  12. Effect of food type and concentration on growth and fatty acid composition of early larvae of the anchovy (Engraulis encrasicolus) reared under laboratory conditions

    KAUST Repository

    Garrido, Susana; Saiz, Enric; Peters, Janna L.; Ré , Pedrobarcia; Á lvarez, Paula; Cotano, Unai; Herrero, D. L.; de Murguí a, Amalia Martí nez; Irigoien, Xabier

    2012-01-01

    Experiments were conducted during the summer of 2008 and 2009 to study the growth of early post yolk-sac European anchovy (Engraulis encrasicolus, Linnaeus, 1758) larvae reared under different food regimes. The fatty acid composition was used to assess nutritional condition of the larvae. Prey items used in the experiments were Gymnodinium sanguineum, Brachionus plicatilis and nauplii of the copepods Acartia grani and Euterpina acutifrons. Food type and concentration affected the growth of the larvae. Mixed diets composed of rotifers and copepod nauplii at high concentration resulted in higher anchovy larvae growth rates in comparison with single-prey diets using either rotifers or copepod nauplii. The addition of the dinoflagellate G. sanguineum (25-50cellsml -1) to the prey offered did not enhance significantly larval growth. Highest growth rates of anchovy larvae (0.28mmd -1) were obtained using high concentrations of a mixed diet, particularly the combination of rotifers and A. grani nauplii. Fatty acid composition at hatch was similar to the composition observed in the field, but during larvae ontogeny there was a marked decrease in the contribution of polyunsaturated fatty acids such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Such difference reflects the high requirements of these PUFA for larvae development, and suggests that the food offered failed to fulfill the larvae nutritional requirements. The growth rates obtained in our experiments were, overall, in the lower range of those observed in natural conditions. Taking into considerations the fact that larvae in the field are expected to encounter lower prey concentrations, we discuss the reasons for such disagreement. © 2012 Elsevier B.V.

  13. Effect of live and dry food on rearing of tench (Tinca tinca L. larvae under controlled conditions

    Directory of Open Access Journals (Sweden)

    Daniel Żarski

    2011-01-01

    Full Text Available In the current paper we present a method of rearing tench (Tinca tinca L. larvae under controlled conditions, fed on dry food (Gemma and Perla and Artemia nauplii or decapsulated cysts of Artemia. Tench larvae were obtained after artificial spawning by aid of Ovopel stimulation. Two experiments were conducted during which fish were divided into 4 groups (in duplicate and placed in 30 dm3 glass fish tanks set up in a recirculating system. The fish were fed ad libitum and reared for 25 days. Larvae were fed exclusively (experiment 1 or after 10 days (experiment 2 of receiving Artemia nauplii with two types of compound feeds and decapsulated cysts of Artemia. The best growth rate was observed in the control group fed on Artemia nauplii and in the group offered decapsulated cysts in both experiments. The highest survival rate, over 96%, occurred in the control group. A twofold worse survival rate was obtained in the group fed exclusively on dry food. Applied transition schedule had significant effect on survival rate among treatments, however it did not influence the percentage of body deformations occurring in groups receiving compound feed only. The results obtained indicate the necessity of applying gradual transition from live food to compound feed and the improvement of feeding schedules in common tench culture.

  14. Carbon and nitrogen stable isotope ratios analysis of food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) in strongly acidic lake Katanuma

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Hideyuki [Tohoku Univ., Sendai (Japan). Graduate School of Science; Kikuchi, Eisuke; Shikano, Shuichi

    2001-12-01

    The food sources for Chironomus acerbiphilus larvae (Diptera Chironomidae) were analyzed using carbon and nitrogen stable isotope ratios in Lake Katanuma. Lake Katanuma is a volcanic and strongly acidic lake (average pH 2.2). In Lake Katanuma, potential sources of diets for the chironomid larvae are limited including a benthic diatom (Pinnularia braunii), a phytoplankton (Chlamydomonas acidophila), sulfate oxidizing bacteria, and vascular plants supplied from vegetation surrounding the lake. Based on the average carbon and nitrogen isotope ratios among these potential sources and sediment, benthic diatoms were considered to be most probable food source of the chironomid larvae. {delta}{sup 13}C values of the chironomid were significantly different among seasons and habitat depths, suggesting that diet of C. acerbiphilus changed seasonally and with habitat depth. (author)

  15. Uptake and bioaccumulation of Cry toxins by an aphidophagous predator

    International Nuclear Information System (INIS)

    Paula, Débora P.; Andow, David A.

    2016-01-01

    Uptake of Cry toxins by insect natural enemies has rarely been considered and bioaccumulation has not yet been demonstrated. Uptake can be demonstrated by the continued presence of Cry toxin after exposure has stopped and gut contents eliminated. Bioaccumulation can be demonstrated by showing uptake and that the concentration of Cry toxin in the natural enemy exceeds that in its food. We exposed larvae of the aphidophagous predator, Harmonia axyridis, to Cry1Ac and Cry1F through uniform and constant tritrophic exposure via an aphid, Myzus persicae, and looked for toxin presence in the pupae. We repeated the experiment using only Cry1F and tested newly emerged adults. Both Cry toxins were detected in pupae, and Cry1F was detected in recently emerged, unfed adults. Cry1Ac was present 2.05 times and Cry1F 3.09 times higher in predator pupae than in the aphid prey. Uptake and bioaccumulation in the third trophic level might increase the persistence of Cry toxins in the food web and mediate new exposure routes to natural enemies. - Highlights: • Uptake and bioaccumulation of two Cry toxins by a larval coccinellid was tested. • Uptake was demonstrated by presence of the toxins in pupae and adults. • Bioaccumulation was shown by higher toxin concentration in pupae than prey. • Cry1Ac was present 2.05× and Cry1F 3.09× higher in predator pupae than prey. • This might increase persistence of Cry toxins in food webs with new exposure routes. - Immatures of the predaceous coccinellid Harmonia axyridis can uptake and bioaccumulate Cry toxins delivered via their aphid prey.

  16. 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

  17. Uptake of atmospheric tritium by market foods

    International Nuclear Information System (INIS)

    Inoue, Y.; Tanaka-Miyamoto, K.; Iwakura, T.

    1992-01-01

    In this paper uptake of tritium by market foods from tritiated water vapor in the air is investigated using cereals and beans purchased in Deep River, Canada. The concentrations of tissue free water tritium (TFWT) and organically bound tritium (OBT) range from 12 to 79% and from 10 to 38% respectively, of that estimated for atmospheric water vapor of the sampling month. The specific activity ratios of OBT to TFWT were constant for cereals, but variable for beans. The elevated OBT was shown to be the result of isotopic exchange of labile hydrogen by the fact that washing the foods with tritium free-water reduced their tritium contents to levels characteristic of their production sites

  18. Intraventricular administration of Tenebrio molitor larvae extract regulates food intake and body weight in mice with high-fat diet-induced obesity.

    Science.gov (United States)

    Seo, Minchul; Kim, Jongwan; Moon, Seong-Su; Hwang, Jae-Sam; Kim, Mi-Ae

    2017-08-01

    We recently reported the in vitro and in vivo antiobesity effects of Tenebrio molitor larvae, a traditional food in many countries, but it remains unknown how the larvae affect appetite regulation in mice with diet-induced obesity. We hypothesized that the extract of T molitor larvae mediates appetite by regulating neuropeptide expression. We investigated T molitor larvae extract's (TME's) effects on anorexigenesis and endoplasmic reticulum (ER) stress-induced orexigenic neuropeptide expression in the hypothalami of obese mice. Intracerebroventricular TME administration suppressed feeding by down-regulating the expression of the orexigenic neuropeptides neuropeptide Y and agouti-related protein. T molitor larvae extract significantly reduced the expression of ER stress response genes. These results suggest that TME and its bioactive components are potential therapeutics for obesity and ER stress-driven disease states. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. 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.

  20. Nutritional Value of Pupae Versus Larvae of Tenebrio molitor (Coleoptera: Tenebrionidae) as Food for Rearing Podisus maculiventris (Heteroptera: Pentatomidae).

    Science.gov (United States)

    Morales-Ramos, Juan A; Rojas, M Guadalupe; Shelby, Kent S; Coudron, Thomas A

    2016-04-01

    Life-table analysis yielded demographic parameter values that indicate that Tenebrio molitor (L.) pupae are potentially more suitable factitious prey to mass-produce the predator Podisus maculiventris (Say) and are more suitable prey than the larvae. P. maculiventris developed faster (23.2 vs. 25.5 d), weighed more (females 80.9 vs. 66.6 mg and males 64.7 vs. 53.7 mg), and had a higher survival rate (0.88 vs. 0.7), fecundity, and reproductive output (87.1 vs. 22.8 eggs/female) when reared on pupae compared with larvae of T. molitor. The total protein content and soluble protein content were significantly higher in pupae (60.2 and 23%, respectively) than larvae (53.1 and 14.4%, respectively). Lipid content was significantly lower in pupae (32.1%) than larvae (35.9%), and larvae had more polyunsaturated fatty acids (83.6 vs. 56.6 mg/g) and less oleic (0.1 mg/g) and steric (6.1 mg/g) acids than pupae (37.3 and 12.3 mg/g, respectively). The total sugar content was not significantly different between pupae and larvae. However, larvae had significantly more fructose than pupae, but pupae had more galactose, glucosamine, glucose, mannose, and trehalose than larvae. Differences in nutritional composition and its impact on predator demographic parameters are potential factors that make the pupal stage a better food source.

  1. Effects of calanoid copepod Schmackeria poplesia as a live food on the growth, survival and fatty acid composition of larvae and juveniles of Japanese flounder, Paralichthys olivaceus

    Science.gov (United States)

    Liu, Guangxing; Xu, Donghui

    2009-12-01

    Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods ( P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated. The results showed that the larvae and juveniles fed with copepods ( S. poplesia) had significantly higher growth rate than those fed with the other two organisms ( P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others ( P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia ( P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its effects on the survival, growth and nutrition composition of the fish.

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Effects of the Monoamine Uptake Inhibitors RTI-112 and RTI-113 on Cocaine- and Food-Maintained Responding in Rhesus Monkeys

    Science.gov (United States)

    SS, Negus; NK, Mello; HL, Kimmel; LL, Howell; FI, Carroll

    2009-01-01

    Cocaine blocks uptake of the monoamines dopamine, serotonin and norepinephrine, and monoamine uptake inhibitors constitute one class of drugs under consideration as candidate “agonist” medications for the treatment of cocaine abuse and dependence. The pharmacological selectivity of monoamine uptake inhibitors to block uptake of dopamine, serotonin and norepinephrine is one factor that may influence the efficacy and/or safety of these compounds as drug abuse treatment medications. To address this issue, the present study compared the effects of 7-day treatment with a non-selective monoamine uptake inhibitor (RTI-112) and a dopamine-selective uptake inhibitor (RTI-113) on cocaine- and food-maintained responding in rhesus monkeys. Monkeys (N=3) were trained to respond for cocaine injections (0.01 mg/kg/inj) and food pellets under a second-order schedule [FR2(VR16:S)] during alternating daily components of cocaine and food availability. Both RTI-112 (0.0032–0.01 mg/kg/hr) and RTI-113 (0.01–0.056 mg/kg/hr) produced dose-dependent, sustained and nearly complete elimination of cocaine self-administration. However, for both drugs, the potency to reduce cocaine self-administration was similar to the potency to reduce food-maintained responding. These findings do not support the hypothesis that pharmacological selectivity to block dopamine uptake is associated with behavioral selectivity to decrease cocaine- vs. food-maintained responding in rhesus monkeys. PMID:18755212

  4. 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.

  5. 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.

  6. 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

  7. The effect of water temperature on food transit time and digestive enzymes activity in Caspian kutum (Rutilus kutum larvae

    Directory of Open Access Journals (Sweden)

    Nahid Ghysvandi

    2014-07-01

    Full Text Available The present study investigates the effects of water temperature on digestive enzymes activity and food transit time in Caspian kutum (Rutilus kutum larvae. Caspian kutum larvae (532 ± 0.05 and 543 ± 0.02 mg were divided into two groups with three replicates and reared at different water temperature i.e. 25.6 ± 0.4°C (T1 and 18.4 ± 0.1°C (T2. At the end of the experiment, sampling of intestine was performed at 0, 1, 3, 5, 8, 16, 24 and 30 h after feeding from each treatment. In T2, food was observed until 24 h after feeding and the intestine was empty 29 h after feeding, while in T1 19 h after feeding the intestine was empty. Digestive enzymes activities were higher in T2 treatment. The peaks of trypsin and alkaline phosphatase enzymes activity were found 8 h after feeding in T1, while occurred 16 h after feeding in T2. The highest chymotrypsin and alpha-amylase enzymes activity were observed 5 and 8h after feeding in T1 and T2, respectively. These results confirmed remarkable effects of temperature on food transit time and digestive enzymes activity of Caspian kutum.

  8. Recognition and uptake of free and nanoparticle‐bound betalactoglobulin – a food allergen – by human monocytes

    DEFF Research Database (Denmark)

    Marengo, Mauro; Bonomi, Francesco; Iametti, Stefania

    2011-01-01

    Scope: To improve our understanding of the interaction of food allergens with cells of the immune system, the endocytosis by human monocytes of bovine β‐lactoglobulin (BLG) and ovomucoid (OM) – two major food allergens – and human serum albumin (HSA) was studied. Methods and results: BLG......, and HSA were conjugated to MNPs also labeled with a fluorescent probe. The uptake of these materials by human monocytes was monitored through flow cytometry, and compared with fluorescent MNPs and the free fluorescently labeled proteins, confirming higher uptake of the BLG‐conjugated MNPs versus non......‐conjugated MNPs. OM but not HSA conjugation to particles enhanced uptake of the MNPs. Confocal microscopy provided direct evidence of the actual internalization of BLG–MNP conjugates into the cytoplasm. Conclusions: These results contribute to the current understanding of the interaction between food allergens...

  9. Physiological effects and cellular responses of metamorphic larvae and juveniles of sea urchin exposed to ionic and nanoparticulate silver.

    Science.gov (United States)

    Magesky, Adriano; Ribeiro, Ciro A Oliveiro; Pelletier, Émilien

    2016-05-01

    The widespread use of silver nanoparticles (AgNPs) would likely result in their discharge into wastewater and inevitable release in densely populated coastal areas. It is known that AgNPs can cause harmful effects to marine fauna, but how they affect development stages is still an open question. In order to understand in details how polymer-coated AgNPs (PAAm-AgNPs) (from 0.19 to 4.64mM as Ag) can affect critical stages of marine invertebrate development, metamorphic larvae and juveniles of sea urchins were used as biological models. Multidimensional scaling (MDS) approach based on Bray-Curtis similarity matrix with PERMANOVA showed organisms in a multivariate space undergoing through different physiological conditions as a function of time, chemical forms of silver, nominal concentrations, and presence or absence of food. Sublethal effects such as lethargy, oedema and immobility mainly characterized PAAm-AgNPs effects with juveniles and postlarvae, whereas necrosis and death arose in Ag(+) conditions in short-term tests. Chronically exposed metamorphic larvae had their morphogenic processes interrupted by PAAm-AgNPs and a high mortality rate was observed in recovery period. On the contrary, Ag(+) ions caused progressive mortality during exposure, but a quick recovery in uncontaminated seawater was observed. By means of fluorescent markers we showed that nanosilver could be transferred between consecutive stages (swimming larvae and postlarvae) and highlighted how important is food to enhance PAAm-AgNPs uptake. Using TEM we observed that unfed juveniles had nanosilver aggregates mostly restricted to their coelomic sinuses, while metamorphic larvae already had nano-contamination overspread in different tissues and blastocoel. Our main hypothesis for nanotoxicity of PAAM-AgNPs relies on the slow dissolution of nano-core over time, but in this study the effects of particulate silver form itself are also evoked. Main mechanisms governing tissular and cellular responses

  10. Age validation and growth of yolked larvae of Patagonotothen tessellata (Richardson, 1845 (Pisces: Nototheniidae from the rocky littoral of the Beagle Channel, Argentina

    Directory of Open Access Journals (Sweden)

    Gustavo Alfredo Rae

    1999-12-01

    Full Text Available Age and growth estimation of Patagonotothen tessellata larvae over the endogenous period was estimated by examining their otolith microstructure and the associated increment deposition rate. Analyzed specimens were incubated from egg-masses collected in Lapataia Bay, Beagle Channel, Argentina. Validation was performed by monitoring reared larvae of known ages. Actual age and increment count were regressed suggesting a daily deposition of one ring in the otolith, which began at hatching time and continued until larvae reached sixteen days old (time of massive mortality. Mean lengths at each age were estimated using Richards´ growth function; their constant (m attained a value close to zero indicating that the data fitted to the von Bertalanffy model. Absolute growth rate was 0.55 mm*d-1of total length at hatching, dropped near zero on the fifth day after hatching and afterwards, there was no growth. Yolk absorption rate (expressed as a ratio between minor axis/major axis of the vitelline-sac showed a similar variation as that observed in absolute growth rate during the endogenous period. The total yolk absorption took five days in the unfed larvae group and seven days in the fed larvae group. The rapid absorption of the yolk and the observed growth pattern suggest that Patagonotothen tessellata larvae have a short endogenous period, reaching the state of first food uptake five days after hatching.

  11. Bioaccumulation of 14C-Labeled Graphene in an Aquatic Food Chain through Direct Uptake or Trophic Transfer.

    Science.gov (United States)

    Dong, Shipeng; Xia, Tian; Yang, Yu; Lin, Sijie; Mao, Liang

    2018-01-16

    The growing applications of graphene materials warrant a careful evaluation of their environmental fate in aquatic food webs. Escherichia coli (Bacteria), Tetrahymena thermophila (protozoa), Daphnia magna (zooplankton), and Danio rerio (vertebrate) were used to build aquatic food chains to investigate the waterborne uptake and trophic transfer of 14 C-labeled graphene. Body burden factor (BBF) and trophic transfer factor (TTF) were analyzed for each organism and food chain to assess the bioaccumulation and biomagnification of graphene. The test organisms have high potential of accumulating graphene via direct uptake from culture medium with log-transformed BBF (log BBF) values of 3.66, 5.1, 3.9, and 1.62 for each organism, respectively. In the food chain from E. coli to T. thermophila, the calculated TTFs of 0.2 to 8.6 indicate the high trophic transfer potential in this aquatic food chain. However, the TTFs calculated for the food chain from T. thermophila to D. magna and from D. magna to D. rerio are much lower than 1, indicating that biomagnification was unlikely to occur in these food chains. Body burden measured for dietary uptake by T. thermophila, D. magna, and D. rerio are higher than that via waterborne exposure in a similar nominal concentration, respectively, indicating that trophic transfer is a nonnegligible route for the bioaccumulation of graphene in organisms.

  12. Food and feeding habits of Omobranchus sp. (Blenniidae: Omobranchini) larvae in the Seagrass-Mangrove ecosystem of Johor Strait, Malaysia.

    Science.gov (United States)

    Ara, Roushon; Arshad, Aziz; Amin, S M Nurul; Ghaffar, Mazlan Abd

    2016-07-01

    The stomach contents of Omobranchus sp. (family Blenniidae) larvae were investigated in a seagrass-mangrove based ecosystem in Johor Strait, Malaysia from October 2007 to September 2008. Specimens of larval fish were collected through subsurface towing of a Bongo net from five different stations. The stomach sacs of 267 Omobranchus sp. larvae were separated and observed, which comprised of 24 significant food stuffs belonging to 6 main groups viz. phytoplankton (62.45%), zooplankton (18.24%), algae (5.56%), plant-like particles (5.75%), debris (4.22%) and unidentified particles (2.03%). In situ water parameters were also measured throughout the sampling cruises. There was a strong and significant positive correlation between stomach phytoplankton and salinity (r = 0.658, p < 0.05).? Canonical correlation analysis indicated a weak relationship (29.8%) between stomach contents and physico-chemical parameters. Only salinity appeared to be the controlling factor for the stomach contents of Omobranchus sp. larvae in the investigated area. Based on the stomach content analysis, it could be concluded that Omobranchus sp. were mainly herbivorous during the larval stages. ?

  13. Metal uptake and acute toxicity in zebrafish: Common mechanisms across multiple metals

    Energy Technology Data Exchange (ETDEWEB)

    Alsop, Derek, E-mail: alsopde@mcmaster.ca [Department of Biology, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4K1 (Canada)

    2011-10-15

    All metals tested reduced calcium uptake in zebrafish larvae. However, it was whole body sodium loss that was functionally related to toxicity. The zebrafish larvae acute toxicity assay save time, space and resources. - Abstract: Zebrafish larvae (Danio rerio) were used to examine the mechanisms of action and acute toxicities of metals. Larvae had similar physiological responses and sensitivities to waterborne metals as adults. While cadmium and zinc have previously been shown to reduce Ca{sup 2+} uptake, copper and nickel also decreased Ca{sup 2+} uptake, suggesting that the epithelial transport of all these metals is through Ca{sup 2+} pathways. However, exposure to cadmium, copper or nickel for up to 48 h had little or no effect on total whole body Ca{sup 2+} levels, indicating that the reduction of Ca{sup 2+} uptake is not the acute toxic mechanism of these metals. Instead, mortalities were effectively related to whole body Na{sup +}, which decreased up to 39% after 48 h exposures to different metals around their respective 96 h LC50s. Decreases in whole body K{sup +} were also observed, although they were not as pronounced or frequent as Na{sup +} losses. None of the metals tested inhibited Na{sup +} uptake in zebrafish (Na{sup +} uptake was in fact increased with exposure) and the observed losses of Na{sup +}, K{sup +}, Ca{sup 2+} and Mg{sup 2+} were proportional to the ionic gradients between the plasma and water, indicating diffusive ion loss with metal exposure. This study has shown that there is a common pathway for metal uptake and a common mechanism of acute toxicity across groups of metals in zebrafish. The disruption of ion uptake accompanying metal exposure does not appear to be responsible for the acute toxicity of metals, as has been previously suggested, but rather the toxicity is instead due to total ion loss (predominantly Na{sup +}).

  14. Enantiomerization and enantioselective bioaccumulation of benalaxyl in Tenebrio molitor larvae from wheat bran.

    Science.gov (United States)

    Gao, Yongxin; Chen, Jinhui; Wang, Huili; Liu, Chen; Lv, Xiaotian; Li, Jianzhong; Guo, Baoyuan

    2013-09-25

    The enantiomerization and enatioselecive bioaccumulation of benalaxyl by dietary exposure to Tenebrio molitor larvae under laboratory conditions were studied by HPLC-MS/MS. Exposure of enantiopure R-benalaxyl and S-benalaxyl in T. molitor larvae revealed significant enantiomerization with formation of the R enantiomers from the S enantiomers, and vice versa. Enantiomerization was not observed in wheat bran during the period of 21 days. For the bioaccumulation experiment, the enantiomer fraction in T. molitor larvae was maintained approximately at 0.6, whereas the enantiomer fraction in wheat bran was maintained at 0.5; in other words, the bioaccumulation of benalaxyl was enantioselective in T. molitor larvae. Mathematical models for a process of uptake, degradation, and enantiomerization were developed, and the rates of uptake, degradation, and enantiomerization of R-benealaxyl and S-benealaxyl were estimated, respectively. The results were that the rate of uptake of R-benalaxyl (kRa = 0.052 h(-1)) was slightly lower than that of S-benalaxyl (kSa = 0.061 h(-1)) from wheat bran; the rate of degradation of R-benalaxyl (kRd = 0.285 h(-1)) was higher than that of S-benalaxyl (kSd = 0.114 h(-1)); and the rate of enantiomerization of R-benalaxyl (kRS = 0.126 h(-1)) was higher than that of S-benalaxyl (kSR = 0.116 h(-1)). It was suggested that enantioselectivtiy 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 chiral pesticides.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Ingestion of bacteria by cod (Gadus morhua L.) larvae. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983

    OpenAIRE

    Olafsen, Jan A.

    1984-01-01

    The uptake of Rhodamine-labelled bacteria by cod larvae was demonstrated using a fluorescent microscopy technique, which allowed a quick estimate of bacterial uptake and gut clearance. Live or heat-killed bacteria, isolated from cod-eggs, were rapidly ingested by larvae at yolk-sac and older stages. A substantial uptake could be seen after 15 min exposure, and eventually the bacteria became densely packed in the digestive tract. Some morphological details in the develo...

  17. Feeding of larvae of the hybrid surubim Pseudoplatystoma sp. under two conditions of food management - doi: 10.4025/actascibiolsci.v35i2.15359

    Directory of Open Access Journals (Sweden)

    Aryadne Simões Rocha

    2013-05-01

    Full Text Available We evaluated the growth and diet composition of hybrid surubim larvae (Pseudoplatystoma corruscans x P. reticulatum produced in two fish farming by using different systems of feeding with natural plankton: M I, larvae are transferred to fertilized fish pond for being freely fed with natural plankton; M II, larvae are remained inside laboratory in glass fiber boxes and plankton are gathered with a plankton net and offered in a controlled way. It was collected 10 individuals daily during the feeding period with live plankton for 20 days. After the biometry, stomachs were opened and the food items identified and quantified by the volumetric method. The items were represented by algae, protozoa, microcrustacean, insect larvae and surubim fragments (cannibalism. The items with higher volumetric percentage were Chironomidae larvae (29.25% followed by surubim fragments (19.68% in M I, and surubim fragments (21.85% and Moina micrura (19.97% in MII. The items Chydorus sp., Diaphanosoma sp., sp. Macrothrix and Ephemeroptera larvae were found only in fish of M I, while algae Ulothrix sp., Oscillatoria sp. and the protozoa Difflugia sp were only found in stomachs of surubim from M II. Regarding the growth, the surubim had grown faster in M I.

  18. Chironomidae larvae (Diptera) of Neotropical floodplain: overlap niche in different habitats.

    Science.gov (United States)

    Butakka, C M M; Ragonha, F H; Takeda, A M

    2014-05-01

    The niche overlap between trophic groups of Chironomidae larvae in different habitats was observed between trophic groups and between different environments in Neotropical floodplain. For the evaluation we used the index of niche overlap (CXY) and analysis of trophic networks, both from the types and amount of food items identified in the larval alimentary canal. In all environments, the larvae fed on mainly organic matter such as plants fragments and algae, but there were many omnivore larvae. Species that have high values of food items occurred in diverse environments as generalists with great overlap niche and those with a low amount of food items with less overlap niche were classified as specialists. The largest number of trophic niche overlap was observed among collector-gatherers in connected floodplain lakes. The lower values of index niche overlap were predators. The similarity in the diet of different taxa in the same niche does not necessarily imply competition between them, but coexistence when the food resource is not scarce in the environment even in partially overlapping niches.

  19. Cloning and molecular ontogeny of digestive enzymes in fed and food-deprived developing gilthead seabream (Sparus aurata) larvae.

    Science.gov (United States)

    Mata-Sotres, José Antonio; Martos-Sitcha, Juan Antonio; Astola, Antonio; Yúfera, Manuel; Martínez-Rodríguez, Gonzalo

    2016-01-01

    We have determined the expression pattern of key pancreatic enzymes precursors (trypsinogen, try; chymotrypsinogen, ctrb; phospholipase A2, pla2; bile salt-activated lipase, cel; and α-amylase, amy2a) during the larval stage of gilthead seabream (Sparus aurata) up to 60days after hatching (dph). Previously, complete sequences of try, cel, and amy2a were cloned and phylogenetically analyzed. One new isoform was found for cel transcript (cel1b). Expression of all enzyme precursors was detected before the mouth opening. Expression of try and ctrb increased during the first days of development and then maintained high values with some fluctuations during the whole larval stage. The prolipases pla2 and cel1b increased from first-feeding with irregular fluctuation until the end of the experiment. Contrarily, cel1a maintained low expression values during most of the larval stage increasing at the end of the period. Nevertheless, cel1a expression was negligible as compared with cel1b. The expression of amy2a sharply increased during the first week followed by a gradual decrease. In addition, a food-deprivation experiment was performed to find the differences in relation to presence/absence of gut content after the opening of the mouth. The food-deprived larvae died at 10dph. The expression levels of all digestive enzymes increased up to 7dph, declining sharply afterwards. This expression pattern up to 7dph was the same observed in fed larvae, confirming the genetic programming during the early development. Main digestive enzymes in gilthead seabream larvae exhibited the same expression profiles than other marine fish with carnivorous preferences in their juvenile stages. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. [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.

  1. 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...

  2. The role of photosynthesis and food uptake for the growth of marine mixotrophic dinoflagellates

    DEFF Research Database (Denmark)

    Hansen, Per Juel

    2011-01-01

    Mixotrophy (i.e. combined use of photosynthesis and food uptake for growth) is widespread among marine dinoflagellates. Species with permanent chloroplasts generally display a growth response towards irradiance like an ordinary autotrophic alga. However, some species cannot grow in the light...

  3. 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

  4. 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

  5. Bioaccumulation of arsenic and silver by the caddisfly larvae Hydropsyche siltalai and H. pellucidula: A biodynamic modeling approach

    Energy Technology Data Exchange (ETDEWEB)

    Awrahman, Zmnako A., E-mail: zmnako.awrahman@uj.edu.pl [Institute of Environmental Science, Jagiellonian University, Krakow 30-348 (Poland); Rainbow, Philip S.; Smith, Brian D. [Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Khan, Farhan R. [Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Department of Environmental, Social and Spatial Change (ENSPAC), Roskilde University, Universitetsvej 1, PO Box 260, Roskilde DK-4000 (Denmark); Bury, Nicolas R. [Nutritional Sciences Division, King’s College London, Franklin–Wilkins Building, 150 Stamford Street, London SE1 9NH (United Kingdom); Fialkowski, Wojciech [Institute of Environmental Science, Jagiellonian University, Krakow 30-348 (Poland)

    2015-04-15

    Highlights: • Biodynamic models were used to predict steady state As and Ag concentrations. • Uptake and efflux rate constants for As and Ag were measured in caddisfly species. • Dietborne As was the predominant exposure route in two caddisfly species. • Diet was the only exposure route of bioaccumulated Ag in the investigated caddisflies. - Abstract: Biodynamic modeling was used to investigate the uptake and bioaccumulation of arsenic and silver from water and food by two Hydropsychid caddisfly larvae: Hydropsyche siltalai and Hydropsyche pellucidula. Radiotracer techniques determined the uptake rate constants of arsenic and silver from water, and assimilation efficiencies from food, and their subsequent loss rate constants after accumulation from either route. The uptake rate constants (±SE) of As and Ag from solution were 0.021 ± 0.005 and 0.350 ± 0.049 L g{sup −1} day{sup −1}, respectively, for H. siltalai, and 0.435 ± 0.054 and 0.277 ± 0.021 L g{sup −1} day{sup −1}, respectively, for H. pellucidula in moderately hard synthetic water at 10 °C. The assimilation efficiencies (±SE) of As and Ag from radiolabeled ingested food were 46.0 ± 7.7% and 75.7 ± 3.6%, respectively, for H. siltalai, and 61.0 ± 4.2% and 52.6 ± 8.6%, respectively, for H. pellucidula. Ag, but not As, AEs were significantly different between species. The AE of Ag differed from the AE of As in H. siltalai, but not in H. pellucidula. Mean efflux rate constants after accumulation of metals from solution or food ranged from 0.039 to 0.190 day{sup −1}. The efflux rate constants of As and Ag accumulated from solution were significantly lower than those of As and Ag assimilated from ingested food in both species. Experimentally derived k{sub u} and k{sub e} values were then used to predict As and Ag tissue concentrations in hydropsychids collected from 13 UK sites, including metal-contaminated streams in Cornwall. Arsenic and silver concentrations in environmental water

  6. 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

  7. 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.

  8. Complete validation of a unique digestion assay to detect Trichinella larvae in horse meat demonstrates the reliability of this assay for meeting food safety and trade requirements.

    Science.gov (United States)

    Forbes, L B; Hill, D E; Parker, S; Tessaro, S V; Gamble, H R; Gajadhar, A A

    2008-03-01

    A tissue digestion assay using a double separatory funnel procedure for the detection of Trichinella larvae in horse meat was validated for application in food safety programs and trade. The assay consisted of a pepsin-HCl digestion step to release larvae from muscle tissue and two sequential sedimentation steps in separatory funnels to recover and concentrate larvae for detection with a stereomicroscope. With defined critical control points, the assay was conducted within a quality assurance system compliant with International Organization for Standardization-International Electrotechnical Commission (ISO/IEC) 17025 guidelines. Samples used in the validation were obtained from horses experimentally infected with Trichinella spiralis to obtain a range of muscle larvae densities. One-, 5-, and 10-g samples of infected tissue were combined with 99, 95, and 90 g, respectively, of known negative horse tissue to create a 100-g sample for testing. Samples of 5 and 10 g were more likely to be positive than were 1-g samples when larval densities were less than three larvae per gram (lpg). This difference is important because ingested meat with 1 lpg is considered the threshold for clinical disease in humans. Using a 5-g sample size, all samples containing 1.3 to 2 lpg were detected, and 60 to 100% of samples with infected horse meat containing 0.1 to 0.7 lpg were detected. In this study, the double separatory funnel digestion assay was efficient and reliable for its intended use in food safety and trade. This procedure is the only digestion assay for Trichinella in horse meat that has been validated as consistent and effective at critical levels of sensitivity.

  9. 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.

  10. 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).

  11. 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

  12. The uptake of radioactive phosphorus by brown trout (Salmo trutta L.) from water and food

    International Nuclear Information System (INIS)

    Winpenny, K.; Knowles, J.F.; Smith, D.L.

    1998-01-01

    Brown trout were exposed to 32 P in their tank water (7.4 Bq l -1 ) and the uptake to muscle followed over 6 weeks. A steady-state concentration factor (C ss ) of 1.7 and a biological half-time for clearance (tb1/2)) of 45 days were calculated from the results. The low C ss ) indicates that uptake from water is not a major route of 32 P accumulation in these fish. Brown trout were given a single 32 P-spiked meal, and the uptake and clearance in muscle, liver and blood followed over 6 weeks. Assimilation of the isotope by these organs was low, the maximum activity in whole muscle reaching only 0.2-0.4% of that in the meal with lower values in the other two organs. There was no appreciable clearance of 32 P from muscle during the experiment. The slow clearance of 32 P after uptake from water and lack of any clearance after uptake from food indicates that the C ss for this isotope following uptake by either route is likely to depend on radioactive decay rather than intake rate and physiological clearance. (author)

  13. 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)

  14. 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

  15. 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)

  16. 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

  17. 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 ...

  18. 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.

  19. 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

  20. 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...

  1. A generic guide to the larvae of the Nearctic Tanytarsini, (Chironomidae:diptera)

    Science.gov (United States)

    Steiner, J.W.; Doughman, J.S.; Moore, C.R.

    1982-01-01

    Larvae of the tribe Tanytarsini occur in nearly every aquatic habitat in North America where they act as primary consumers in the food chain. This new taxonomic guide overcomes some deficiencies in existing keys to this tribe and the reviewed and updated taxonomy enables identification of the larvae that may be useful as ecological indicators. Over 2,000 specimens from 26 states were examined, identified and measured in this study. The following genera were included: Stempellinell, Zavrelia, Stempellina, Constempellina, Corynocera, Cladotanytarsus,.. Paratanytarsus, Rheotanytarsus,. Micropsectra, Lauterbornia, Nimbocera, Tanytarsus and Neozavrelia. Photographs illustrate mature larvae of these genera with the exception of Zavrelia and Neozavrelia which are not known to exist in North America. The morphological data, Which are summarized in a table of distinctive characteristics and the dichotomous key, enable identification to genus. Notes on range, habitat and food preference are included, and species identifications are presented where applicable.

  2. 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)

  3. Food availability drives plastic self-repair response in a basal metazoan-case study on the ctenophore Mnemiopsis leidyi A. Agassiz

    DEFF Research Database (Denmark)

    Bading, Katharina Tissy; Kaehlert, Sarah; Chi, Xupeng

    2017-01-01

    -animals instead. Yet, the driving factors of this phenomenon have not been addressed so far. This study sheds new light on how differences in food availability affect self-repair choice and regeneration success in cydippid larvae of M. leidyi. As expected, high food availability favored whole-body regeneration....... However, under low food conditions half-animals became the preferential self-repair mode. Remarkably, both regenerating and half-animals showed very similar survival chances under respective food quantities. As a consequence of impaired food uptake after injury, degeneration of the digestive system would...... often occur indicating limited energy storage capacities. Taken together, this indicates that half-animals may represent an alternative energy-saving trajectory which implies self-repair plasticity as an adaptive trade-off between high regeneration costs and low energy storage capacities. We conclude...

  4. 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

  5. Developmental toxicity of oxidized multi-walled carbon nanotubes on Artemia salina cysts and larvae: Uptake, accumulation, excretion and toxic responses.

    Science.gov (United States)

    Zhu, Song; Luo, Fei; Tu, Xiao; Chen, Wei-Chao; Zhu, Bin; Wang, Gao-Xue

    2017-10-01

    Using Artemia salina (A. salina) cysts (capsulated and decapsulated) and larvae [instar I (0-24 h), II (24-48 h) and III (48-72 h)] as experimental models, developmental toxicity of oxidized multi-walled carbon nanotubes (O-MWCNTs) was evaluated. Results revealed that hatchability of capsulated and decapsulated cysts was significantly decreased (p larvae in 600 mg/L. The EC 50 values for swimming inhibition of instar I, II and III were 535, 385 and 472 mg/L, respectively. Instar II showed the greatest sensitivity to O-MWCNTs, and followed by instar III, instar I, decapsulated cysts and capsulated cysts. Effects on hatchability, mortality and swimming were accounted for O-MWCNTs rather than metal catalyst impurities. Body length was decreased with the concentrations increased from 0 to 600 mg/L. O-MWCNTs attached onto the cysts, gill and body surface, resulting in irreversible damages. Reactive oxygen species, malondialdehyde content, total antioxidant capacity and antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) activities were increased following exposure, indicating that the effects were related to oxidative stress. O-MWCNTs were ingested and distributed in phagocyte, lipid vesicle and intestine. Most of the accumulated O-MWCNTs were excreted by A. salina at 72 h, but some still remained in the organism. Data of uptake kinetics showed that O-MWCNTs contents in A. salina were gradually increased from 1 to 48 h and followed by rapidly decreased from 48 to 72 h with a range from 5.5 to 28.1 mg/g. These results so far indicate that O-MWCNTs have the potential to affect aquatic organisms when released into the marine ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Uptake and elimination of aromatic hydrocarbons a chlorinated biphenyl in eggs and larvae of cod Gadus morhua

    OpenAIRE

    Solbakken, Jan Erik; Tilseth, Snorre; Palmork, Karsten H.

    1984-01-01

    Artificially fertilized eggs and newly hatched larvae of cod Gadus rnorhua L. were exposed to 14C labelled naphthalene, phenanthrene, benzo(a)pyrene and 2. 4. 5. 2', 4', 5'-hexachlorobiphenyl (PCB) for 24 h and thereafter transferred to clean seawater. Radioactivity in eggs and larvae was measured at different times during exposure and after transfer to clean seawater. Maximum accumulation was found with phenanthrene, whereas naphthalene accumulated only slightly in both eggs a...

  7. 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.

  8. Attraction to Carbon Dioxide from Feeding Resources and Conspecific Neighbours in Larvae of the Rhinoceros Beetle Trypoxylus dichotomus.

    Directory of Open Access Journals (Sweden)

    Wataru Kojima

    Full Text Available Saprophagous (feeding on decaying matter insects often use carbon dioxide (CO2 as a cue for finding food. Humus-feeding larvae of the giant rhinoceros beetle Trypoxylus dichotomus exhibit a clumped distribution in natural microhabitats, but the mechanisms driving the distribution were unknown. Herein, I examined whether larvae use CO2 as a cue for fermented humus and aggregate in the vicinity of the food. I found that (i larvae of T. dichotomus are strongly attracted to CO2, (ii larvae orient toward highly fermented humus when given a choice between highly and poorly fermented humus, (iii the highly fermented humus emits more CO2 than the poorly fermented humus, and (iv larvae grow larger when fed highly fermented humus rather than poorly fermented humus. The clumped distribution of larvae is probably formed along the concentration gradient of CO2 induced by heterogeneity of fermented organic materials in soil. My laboratory experiments also revealed that larvae are chemically attracted to each other. Moreover, CO2 concentrations in soil were increased by the larval respiration, and small amounts of CO2 (much less than emitted during respiration by a single larva were sufficient for larval attraction. These results suggest that not only response to fermented food resources, but also respiratory CO2 from conspecifics may lead to aggregation. Enhanced densities resulted in reduced weight gain under experimental conditions. However, exploiting a high-value resource at enhanced densities still led to greater body weight compared to individually exploiting a low-value resource. This demonstrates the adaptive value of the response to CO2 sources in this species.

  9. Attraction to Carbon Dioxide from Feeding Resources and Conspecific Neighbours in Larvae of the Rhinoceros Beetle Trypoxylus dichotomus.

    Science.gov (United States)

    Kojima, Wataru

    2015-01-01

    Saprophagous (feeding on decaying matter) insects often use carbon dioxide (CO2) as a cue for finding food. Humus-feeding larvae of the giant rhinoceros beetle Trypoxylus dichotomus exhibit a clumped distribution in natural microhabitats, but the mechanisms driving the distribution were unknown. Herein, I examined whether larvae use CO2 as a cue for fermented humus and aggregate in the vicinity of the food. I found that (i) larvae of T. dichotomus are strongly attracted to CO2, (ii) larvae orient toward highly fermented humus when given a choice between highly and poorly fermented humus, (iii) the highly fermented humus emits more CO2 than the poorly fermented humus, and (iv) larvae grow larger when fed highly fermented humus rather than poorly fermented humus. The clumped distribution of larvae is probably formed along the concentration gradient of CO2 induced by heterogeneity of fermented organic materials in soil. My laboratory experiments also revealed that larvae are chemically attracted to each other. Moreover, CO2 concentrations in soil were increased by the larval respiration, and small amounts of CO2 (much less than emitted during respiration by a single larva) were sufficient for larval attraction. These results suggest that not only response to fermented food resources, but also respiratory CO2 from conspecifics may lead to aggregation. Enhanced densities resulted in reduced weight gain under experimental conditions. However, exploiting a high-value resource at enhanced densities still led to greater body weight compared to individually exploiting a low-value resource. This demonstrates the adaptive value of the response to CO2 sources in this species.

  10. Effect of the parasitoid Diaeretiella rapae on the feeding rate of its host Brevicoryne brassicae

    International Nuclear Information System (INIS)

    Couchman, J.R.; King, P.E.

    1979-01-01

    The food uptake by Brevicoryne brassicae, as measured by accumulation of radiophosphorus, is influenced by the presence of developing larvae of the parasitoid Diaeretiella rapae. Though the egg and embryonic stages of the parasitoid have no effect on host feeding the presence of a first-instar larva lowers the food uptake. Feeding returns to a level similar to that of non-parasitised aphids when a second-instar parasitoid is present within a host, but drops again when the third instar is reached. Host death occurs during the fourth-larval instar. (Auth.)

  11. 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.

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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. Trophodynamics of Organic Pollutants in Pelagic and Benthic Food Webs of Lake Dianchi: Importance of Ingested Sediment As Uptake Route.

    Science.gov (United States)

    Fan, Senrong; Wang, Beili; Liu, Hang; Gao, Shixiong; Li, Tong; Wang, Shuran; Liu, Yong; Liu, Xueqin; Wan, Yi

    2017-12-19

    Habitat is of great importance in determining the trophic transfer of pollutants in freshwater ecosystems; however, the major factors influencing chemical trophodynamics in pelagic and benthic food webs remain unclear. This study investigated the levels of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), polycyclic aromatic hydrocarbons (PAHs), and substituted PAHs (s-PAHs) in 2 plankton species, 6 invertebrate species, and 10 fish species collected from Lake Dianchi in southern China. Relatively high concentrations of PAHs and s-PAHs were detected with total concentrations of 11.4-1400 ng/g wet weight (ww) and 5.3-115 ng/g ww, respectively. Stable isotope analysis and stomach content analysis were applied to quantitatively determine the trophic level of individual organisms and discriminate between pelagic and benthic pathways, and the trophodynamics of the detected compounds in the two food webs were assessed. P,p'-DDE was found to exhibit relatively higher trophic magnification rate in the pelagic food web than in the benthic food web. In contrast, PAHs and s-PAHs exhibited greater dilution rates along the trophic levels in the pelagic food web. The lower species differences of pollutants accumulated in benthic organisms compared to pelagic organisms is attributable to extra uptake via ingested sediment in benthos. The average uptake proportions of PAHs and s-PAHs via ingested sediment in benthic biotas were estimated to be 31-77%, and that of p,p'-DDE was 46%. The uptake routes are of importance for assessing the trophic magnification potentials of organic pollutants, especially in eutrophic freshwater ecosystems.

  15. Food selection in larval fruit flies: dynamics and effects on larval development

    Science.gov (United States)

    Schwarz, Sebastian; Durisko, Zachary; Dukas, Reuven

    2014-01-01

    Selecting food items and attaining a nutritionally balanced diet is an important challenge for all animals including humans. We aimed to establish fruit fly larvae ( Drosophila melanogaster) as a simple yet powerful model system for examining the mechanisms of specific hunger and diet selection. In two lab experiments with artificial diets, we found that larvae deprived of either sucrose or protein later selectively fed on a diet providing the missing nutrient. When allowed to freely move between two adjacent food patches, larvae surprisingly preferred to settle on one patch containing yeast and ignored the patch providing sucrose. Moreover, when allowed to move freely between three patches, which provided either yeast only, sucrose only or a balanced mixture of yeast and sucrose, the majority of larvae settled on the yeast-plus-sucrose patch and about one third chose to feed on the yeast only food. While protein (yeast) is essential for development, we also quantified larval success on diets with or without sucrose and show that larvae develop faster on diets containing sucrose. Our data suggest that fruit fly larvae can quickly assess major nutrients in food and seek a diet providing a missing nutrient. The larvae, however, probably prefer to quickly dig into a single food substrate for enhanced protection over achieving an optimal diet.

  16. 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

  17. Desenvolvimento "in vitro" de larvas e juvenis de Emerita brasiliensis Schmitt (Crustacea, Decapoda, Hippidae sob diferentes condições de temperatura, salinidade e regime alimentar "In vitro" development of larvae and juveniles of the sand crab Emerita brasiliensis Schmitt (Crustacea, Decapoda, Hippidae under different conditions of temperature, salinity and food diet

    Directory of Open Access Journals (Sweden)

    Ana Clara P. Otegui

    2007-06-01

    Full Text Available Larvas eclodidas em laboratório e juvenis coletados em campo do tatuí Emeritabrasiliensis (Hippidae foram cultivados em diferentes temperaturas e regime alimentar com a finalidade de avaliar as melhores condições para a manutenção da espécie em laboratório. O efeito da freqüência da substituição da água de cultivo sobre o desenvolvimento larvar também foi estudado avaliando-se a sobrevivência, o crescimento e a duração dos estádios larvares. A duração das fases larvares e o crescimento das três últimas fases de zoea correlacionaramse positivamente com a temperatura. As temperaturas testadas, entre 18 e 26ºC não influenciaram a sobrevivência das larvas. Não houve influencia da alimentação e nem da troca de água no desenvolvimento, crescimento e sobrevivência das larvas, bem como das dietas de microalgas na sobrevivência e desenvolvimento dos juvenis.Hatched larvae and field sampled juveniles of the sand crab Emeritabrasiliensis were reared at different temperatures and food diet in order to evaluate the best conditions for laboratory maintenance. The effects of frequency of changing the aquarium seawater on larval development was also studied evaluating the survival, growth and duration of larval stages. The duration of larval stage and growth of the last three zoes phases correlate positively with temperature. Temperatures between 18 and 26ºC did not influence the larval survival. The kind of food and frequency of water exchange did not influence the development, growth, and survival of larvae, as well as the development, and survival of juveniles.

  18. Bacterial fatty acids enhance recovery from the dauer larva in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Tiffany K Kaul

    Full Text Available The dauer larva is a specialized dispersal stage in the nematode Caenorhabditis elegans that allows the animal to survive starvation for an extended period of time. The dauer does not feed, but uses chemosensation to identify new food sources and to determine whether to resume reproductive growth. Bacteria produce food signals that promote recovery of the dauer larva, but the chemical identities of these signals remain poorly defined. We find that bacterial fatty acids in the environment augment recovery from the dauer stage under permissive conditions. The effect of increased fatty acids on different dauer constitutive mutants indicates a role for insulin peptide secretion in coordinating recovery from the dauer stage in response to fatty acids. These data suggest that worms can sense the presence of fatty acids in the environment and that elevated levels can promote recovery from dauer arrest. This may be important in the natural environment where the dauer larva needs to determine whether the environment is appropriate to support reproductive growth following dauer exit.

  19. 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.

  20. Lecithotrophic behaviour in zoea and megalopa larvae of the ghost shrimp Lepidophthalmus siriboia Felder and Rodrigues, 1993 (Decapoda: Callianassidae).

    Science.gov (United States)

    Abrunhosa, Fernando A; Simith, Darlan J B; Palmeira, Carlos A M; Arruda, Danielle C B

    2008-12-01

    Food supply is considered critical for a successful culturing of decapod larvae. However, some species may present yolk reserve sufficient to complete their larval development without external food supply (known as lecithotrophic larval development). In the present study, two experiments were carried out in order to verify whether the callianassid Lepidophthalmus siriboia have lecithotrophic behaviour or, if they need external food for their larval development: Experiment 1, larvae submitted to an initial feeding period and Experiment 2, larvae submitted to an initial starvation period. High survival rate was observed in both experiments, in which only 2 megalopae and 1 zoea III died. These results strongly suggest that larvae of L. siriboia are lecithotrophic as they have sufficiently large yolk reserve to complete their larval development, while the megalopa stage shows facultative lecithotrophy. The larval periods of each stage of the treatments were quite similar and, despite some significant differences in some larval periods, these can be related probably to larval rearing conditions, abiotic factors or, individual variability of larval health, as well as stress caused to the ovigerous females during embryogenesis.

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    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

  3. 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.

  4. Key to marine arthropod larvae

    Directory of Open Access Journals (Sweden)

    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.

  5. Drosophila larvae food intake cessation following exposure to Erwinia contaminated media requires odor perception, Trpa1 channel and evf virulence factor.

    Science.gov (United States)

    Keita, Seydou; Masuzzo, Ambra; Royet, Julien; Kurz, C Leopold

    2017-05-01

    When exposed to microorganisms, animals use several protective strategies. On one hand, as elegantly exemplified in Drosophila melanogaster, the innate immune system recognizes microbial compounds and triggers an antimicrobial response. On the other hand, behaviors preventing an extensive contact with the microbes and thus reducing the risk of infection have been described. However, these reactions ranging from microbes aversion to intestinal transit increase or food intake decrease have been rarely defined at the molecular level. In this study, we set up an experimental system that allowed us to rapidly identify and quantify food intake decreases in Drosophila larvae exposed to media contaminated with bacteria. Specifically, we report a robust dose-dependent food intake decrease following exposure to the bacteria Erwinia carotovora carotovora strain Ecc15. We demonstrate that this response does not require Imd innate immune pathway, but rather the olfactory neuronal circuitry, the Trpa1 receptor and the evf virulence factor. Finally, we show that Ecc15 induce the same behavior in the invasive pest insect Drosophila suzukii. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Eastern Baltic cod : Perspectives from existing data on processes affecting growth and survival of eggs and larvae

    DEFF Research Database (Denmark)

    MacKenzie, Brian; St. John, Michael; Wieland, Kai

    1996-01-01

    exist in our knowledge of processes affecting egg and larval growth and survival, but some promising areas of research are indicated. In particular the seasonality of spawning, deep water oxygen concentrations, predation on eggs, and larval food production require further investigation....... surveys have described food concentrations at appropriate scales for cod larvae, and the species composition of larval diets is unknown. Growth rates for Baltic cod larvae have not been measured and cannot be compared with rates in other areas or to variations in biotic and abiotic factors. Large gaps...

  7. [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.

  8. Effects of starvation on moult cycle and hepatopancreas of Stage I lobster (Homarus americanus) larvae

    Science.gov (United States)

    Anger, K.; Storch, V.; Anger, V.; Capuzzo, J. M.

    1985-06-01

    Effects of feeding and starvation on the moult cycle and on the ultrastructure of hepatopancreas cells were studied in Stage I lobster larvae ( Homarus americanus Milne-Edwards). The relative significance of yolk and first food was quite different in larvae originating from two females. This difference was evident also in the amounts of stored lipid in the R-cells of the larval hepatopancreas. Most larvae from one hatch were, in principle, able to develop exclusively with yolk reserves (without food) to the second instar. The larvae from the second hatch showed lecithotrophic development only to the transition between late intermoult and early premoult (Stages C/D0 of Drachs's moult cycle) of the first larval instar. When initial starvation in this group lasted for 3 days or more, the point of no return (PNR) was exceeded. After the PNR, consumption of food was still possible, but development ceased in the transition C/D0 or in late premoult (D3 4). It is suggested that these stages of the moult cycle are critical points were cessation of development and increased mortality are particularly likely in early larval lobsters under nutritional stress. Examination of hepatopancreas R-cells suggested that the PNR is caused by an irreversible loss of the ability to restore lipid reserves depleted during initial starvation. Initial periods of starvation ending before the PNR prolonged mainly Stage D0 of the same instar (I). During this delay, structural changes in the R-cells caused by the preceding period of starvation were reversed: reduced lipid inclusions, swollen mitochondria, an increased number of residual bodies indicating autolysis, and a reduction of the microvillous processes. Continually starved larvae which showed lecithotrophic development throughout the first instar and were then re-fed after moulting successfully, had later a prolonged intermoult (Stage C) period in the second instar. This shows that, despite occasional lecithotrophy, food is an important

  9. Vectorial competence of larvae and adults of Alphitobius diaperinus in the transmission of Salmonella enteritidis in poultry.

    Science.gov (United States)

    Leffer, Andreia M; Kuttel, Javier; Martins, Lidiane M; Pedroso, Antonio Carlos; Astolfi-Ferreira, Claudete S; Ferreira, Fernando; Ferreira, Antonio J Piantino

    2010-06-01

    The ingestion of food products originating from poultry infected with Salmonella spp. is one of the major causes of food poisoning in humans. The control of poultry salmonellosis is particularly difficult since birds are asymptomatic and numerous factors may expedite the maintenance of bacteria in poultry production facilities. The aim of the study was to determine the vectorial capacity of adults and larvae of Alphitobius diaperinus (Coleoptera: Tenebrionidae) in the experimental transmission of Salmonella Enteritidis phage type 4 to 1-day-old specific pathogen-free White Leghorn chicks. Adult insects and larvae were starved for 1 day, fed for 24 h or 7 days on sterile ration that had been treated with Salmonella Enteritidis phage type 4, and the levels of bacterial infection were determined. Infected adult insects and larvae were fed to groups of day-old chicks, after which bacteria were recovered from cecum, liver, and spleen samples over a 7-day period. Infected larvae were more efficient than adult insects in transmitting Salmonella Enteritidis to chicks. Higher concentrations of bacteria could be reisolated from the cecum, liver, and spleen of chicks that had ingested infected larvae compared with those that had ingested infected adults. The control of A. diaperinus, and particularly of the larvae, represents a critical factor in the reduction of Salmonella spp. in poultry farms.

  10. 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...

  11. Aiptasia sp. larvae as a model to reveal mechanisms of symbiont selection in cnidarians

    KAUST Repository

    Wolfowicz, Iliona

    2016-09-01

    Symbiosis, defined as the persistent association between two distinct species, is an evolutionary and ecologically critical phenomenon facilitating survival of both partners in diverse habitats. The biodiversity of coral reef ecosystems depends on a functional symbiosis with photosynthetic dinoflagellates of the highly diverse genus Symbiodinium, which reside in coral host cells and continuously support their nutrition. The mechanisms underlying symbiont selection to establish a stable endosymbiosis in non-symbiotic juvenile corals are unclear. Here we show for the first time that symbiont selection patterns for larvae of two Acropora coral species and the model anemone Aiptasia are similar under controlled conditions. We find that Aiptasia larvae distinguish between compatible and incompatible symbionts during uptake into the gastric cavity and phagocytosis. Using RNA-Seq, we identify a set of candidate genes potentially involved in symbiosis establishment. Together, our data complement existing molecular resources to mechanistically dissect symbiont phagocytosis in cnidarians under controlled conditions, thereby strengthening the role of Aiptasia larvae as a powerful model for cnidarian endosymbiosis establishment.

  12. Aiptasia sp. larvae as a model to reveal mechanisms of symbiont selection in cnidarians

    KAUST Repository

    Wolfowicz, Iliona; Baumgarten, Sebastian; Voss, Philipp A.; Hambleton, Elizabeth A.; Voolstra, Christian R.; Hatta, Masayuki; Guse, Annika

    2016-01-01

    Symbiosis, defined as the persistent association between two distinct species, is an evolutionary and ecologically critical phenomenon facilitating survival of both partners in diverse habitats. The biodiversity of coral reef ecosystems depends on a functional symbiosis with photosynthetic dinoflagellates of the highly diverse genus Symbiodinium, which reside in coral host cells and continuously support their nutrition. The mechanisms underlying symbiont selection to establish a stable endosymbiosis in non-symbiotic juvenile corals are unclear. Here we show for the first time that symbiont selection patterns for larvae of two Acropora coral species and the model anemone Aiptasia are similar under controlled conditions. We find that Aiptasia larvae distinguish between compatible and incompatible symbionts during uptake into the gastric cavity and phagocytosis. Using RNA-Seq, we identify a set of candidate genes potentially involved in symbiosis establishment. Together, our data complement existing molecular resources to mechanistically dissect symbiont phagocytosis in cnidarians under controlled conditions, thereby strengthening the role of Aiptasia larvae as a powerful model for cnidarian endosymbiosis establishment.

  13. 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.

  14. Adult exposure to ocean acidification is maladaptive for larvae of the Sydney rock oyster Saccostrea glomerata in the presence of multiple stressors.

    Science.gov (United States)

    Parker, Laura M; O'Connor, Wayne A; Byrne, Maria; Coleman, Ross A; Virtue, Patti; Dove, Michael; Gibbs, Mitchell; Spohr, Lorraine; Scanes, Elliot; Ross, Pauline M

    2017-02-01

    Parental effects passed from adults to their offspring have been identified as a source of rapid acclimation that may allow marine populations to persist as our surface oceans continue to decrease in pH. Little is known, however, whether parental effects are beneficial for offspring in the presence of multiple stressors. We exposed adults of the oyster Saccostrea glomerata to elevated CO 2 and examined the impacts of elevated CO 2 (control = 392; 856 µatm) combined with elevated temperature (control = 24; 28°C), reduced salinity (control = 35; 25) and reduced food concentration (control = full; half diet) on their larvae. Adult exposure to elevated CO 2 had a positive impact on larvae reared at elevated CO 2 as a sole stressor, which were 8% larger and developed faster at elevated CO 2 compared with larvae from adults exposed to ambient CO 2 These larvae, however, had significantly reduced survival in all multistressor treatments. This was particularly evident for larvae reared at elevated CO 2 combined with elevated temperature or reduced food concentration, with no larvae surviving in some treatment combinations. Larvae from CO 2 -exposed adults had a higher standard metabolic rate. Our results provide evidence that parental exposure to ocean acidification may be maladaptive when larvae experience multiple stressors. © 2017 The Author(s).

  15. Seasonal changes in food uptake by the sea cucumber Apostichopus japonicus in a farm pond: Evidence from C and N stable isotopes

    Science.gov (United States)

    Sun, Zhenlong; Gao, Qinfeng; Dong, Shuanglin; Shin, Paul K. S.; Wang, Fang

    2013-03-01

    This study investigated the seasonal changes in carbon (C) and nitrogen (N) stable isotope values of several typical food sources of Apostichopus japonicus in a farm pond, including particulate organic matter (POM), macroalgae, benthic microalgae and animals such as nematode and copepod. The stable isotope technique was used to quantify relative contributions of various sources to the food uptake by A. japonicus. The results showed that significant changes occurred in the C and N stable isotope values of sea cucumber food sources due to the seasonality of micro- or macroalgae prosperity and the fluctuation of environmental conditions. The sea cucumber A. japonicus exhibited corresponding alterations in feeding strategy in response to the changes in food conditions. Calculation with a stable isotope mixing model showed that macroalgae was the principal food source for A. japonicus throughout the 1-yr investigation, with the relative contribution averaging 28.1%-63.2%. The relative contributions of other food sources such as copepod and nematode, POM, benthic microalgae to the total food uptake by sea cucumber averaged 22.6%-39.1%, 6.3% -22.2%, 2.8%-6.5%, and 2.8%-4.2%, respectively. Together these results indicated that the seasonal changes in food sources led to the obvious temporal differences in the relative contribution of various food sources utilized by A. japonicus. Such findings provide the basic scientific information for improving the aquaculture techniques of A. japonicus, particularly for optimizing the food environment of A. japonicus culture in farm ponds.

  16. 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.

  17. 21 CFR 862.1715 - Triiodothyronine uptake test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Triiodothyronine uptake test system. 862.1715... Systems § 862.1715 Triiodothyronine uptake test system. (a) Identification. A triiodothyronine uptake test... plasma. Measurements of triiodothyronine uptake are used in the diagnosis and treatment of thyroid...

  18. 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.

  19. 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...

  20. 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.

  1. Seletividade alimentar de organismos-alimento por formas jovens de pacu Piaractus mesopotamicus (Holmberg, 1887 e curimba Prochilodus lineatus (Valenciennes, 1836 = Selective feeding of food organisms by fish larvae of Piaractus mesopotamicus (Holmberg, 1887 and Prochilodus lineatus (Valenciennes, 1836

    Directory of Open Access Journals (Sweden)

    Nandeyara Ribeiro Marques

    2007-04-01

    Full Text Available Objetivou-se avaliar a seleção alimentar de organismos-alimento por formas jovens de pacu (Piaractus mesopotamicus e curimba (Prochilodus lineatus com diferentes idades (6, 12, 19 e 26 dias, na presença e ausência de Pistia stratiotes. Foram utilizados quatrotratamentos (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba e quatro repetições. A cada sete dias, foram coletadas 24 larvas de cada espécie de peixe dos tanques, sendo estas mantidas em jejum por 24 horas. Depois de distribuídas nos aquários com plâncton, as larvas permaneceram por três horas, sendocoletadas e fixadas para análise, juntamente com as amostras de água. Os tratos digestórios das larvas foram retirados e analisados sob microscópio óptico. Observaram-se diferenças estatísticas na seletividade alimentar de organismos planctônicos por larvas de mesmaespécie, em diferentes idades e também entre larvas de espécies diferentes, com mesma idade, não diferindo quanto à presença ou ausência de P. stratiotes. As formas jovens de pacu e curimba selecionaram organismos similares aos seis dias de idade, passando por alterações até o 26º dia. À medida que se desenvolveram, as larvas de pacu passaram a selecionar cladóceros e ostrácodos e as de curimba, protozoários e algas.Theobjective was to evaluate the feeding selection of food organisms for two species of fish larvae (pacu and curimba at different ages (6, 12, 19 and 26 days after eclosion, in the presence or absence of Pistia stratiotes. Four treatments were used (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba and four replications. Every seven days, 24 fish larvae of each species were collected, and kept without food for 24 hours. Afterbeing distributed in the aquariums with plankton, the larvae stayed for three hours, and were collected and prepared for analysis, along with the water samples. The digestive tract of the fish larvae were

  2. Combined and separated effects of gamma irradiation and bifuran plant extract on the dietary profile of the black cutworm, agitators ipsilon (Hun.) 1- treatment of the eight days old larvae

    International Nuclear Information System (INIS)

    El-Naggar, S.E.M.; Ibrahim, S.M.; Mohamed, H.F.

    2007-01-01

    The combined and separate effects of two sub sterilizing doses 100 or 150 Gy of gamma irradiation and the plant extract Conyza dioscorides (Barnoof) on eight days- old larvae of F1 generation of Agrotis ipsilon as to their ability to consume, digest and utilize food were studied. Gamma irradiation alone reduced the amount of food consumed and digested by the larvae as compared to non-irradiated ones. Also, the utilization efficiency was decreased more significantly at the dose level 150 Gy than at the dose level 100 Gy leading to a reduction in weight gain. The effect of plant extract (Barnoof) alone was non-significantly different at the two tested concentrations 1.5 or 3 % by the solvent (Petroleum ether) treatment. The combined effect of gamma radiation and plant extract on F1 larvae significantly decreased the growth rate of the larvae than when treating them alone as compared to the untreated larvae. Also, the combined effects of gamma radiation and plant extract significantly decreased the utilization of food as indicated by determining both efficiency of conversion of ingested food (E.C.I.) and digested food (E.C.D.) to body matters

  3. Seasonal Changes in Food Uptake by the Sea Cucumber Apostichopus japonicus in a Farm Pond: Evidence from C and N Stable Isotopes

    Institute of Scientific and Technical Information of China (English)

    SUN Zhenlong; GAO Qinfeng; DONG Shuanglin; Paul K.S. Shin; WANG Fang

    2013-01-01

    This study investigated the seasonal changes in carbon (C) and nitrogen (N) stable isotope values of several typical food sources of Apostichopus japonicus in a farm pond,including particulate organic matter (POM),macroalgae,benthic microalgae and animals such as nematode and copepod.The stable isotope technique was used to quantify relative contributions of various sources to the food uptake by A.japonicus.The results showed that significant changes occurred in the C and N stable isotope values of sea cucumber food sources due to the seasonality of micro-or macroalgae prosperity and the fluctuation of environmental conditions.The sea cucumber A.japonicus exhibited corresponding alterations in feeding strategy in response to the changes in food conditions.Calculation with a stable isotope mixing model showed that macroalgae was the principal food source for A.japonicus throughout the 1-yr investigation,with the relative contribution averaging 28.1%-63.2%.The relative contributions of other food sources such as copepod and nematode,POM,benthic microalgae to the total food uptake by sea cucumber averaged 22.6%-39.1%,6.3%-22.2%,2.8%-6.5%,and 2.8%-4.2%,respectively.Together these results indicated that the seasonal changes in food sources led to the obvious temporal differences in the relative contribution of various food sources utilized by A.japonicus.Such findings provide the basic scientific information for improving the aquaculture techniques of A.japonicus,particularly for optimizing the food environment of A.japonicus culture in farm ponds.

  4. Effect of Larval Density on Food Utilization Efficiency of Tenebrio molitor (Coleoptera: Tenebrionidae).

    Science.gov (United States)

    Morales-Ramos, Juan A; Rojas, M Guadalupe

    2015-10-01

    Crowding conditions of larvae may have a significant impact on commercial production efficiency of some insects, such as Tenebrio molitor L. (Coleoptera: Tenebrionidae). Although larval densities are known to affect developmental time and growth in T. molitor, no reports were found on the effects of crowding on food utilization. The effect of larval density on food utilization efficiency of T. molitor larvae was studied by measuring efficiency of ingested food conversion (ECI), efficiency of digested food conversion (EDC), and mg of larval weight gain per gram of food consumed (LWGpFC) at increasing larval densities (12, 24, 36, 48, 50, 62, 74, and 96 larvae per dm(2)) over four consecutive 3-wk periods. Individual larval weight gain and food consumption were negatively impacted by larval density. Similarly, ECI, ECD, and LWGpFC were negatively impacted by larval density. Larval ageing, measured as four consecutive 3-wk periods, significantly and independently impacted ECI, ECD, and LWGpFC in a negative way. General linear model analysis showed that age had a higher impact than density on food utilization parameters of T. molitor larvae. Larval growth was determined to be responsible for the age effects, as measurements of larval mass density (in grams of larvae per dm(2)) had a significant impact on food utilization parameters across ages and density treatments (in number of larvae per dm(2)). The importance of mass versus numbers per unit of area as measurements of larval density and the implications of negative effects of density on food utilization for insect biomass production are discussed. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  5. 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.

  6. 21 CFR 868.1730 - Oxygen uptake computer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxygen uptake computer. 868.1730 Section 868.1730...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1730 Oxygen uptake computer. (a) Identification. An oxygen uptake computer is a device intended to compute the amount of oxygen consumed by a...

  7. 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.

  8. Arsenic Uptake and Translocation in Plants.

    Science.gov (United States)

    Li, Nannan; Wang, Jingchao; Song, Won-Yong

    2016-01-01

    Arsenic (As) is a highly toxic metalloid that is classified as a non-threshold class-1 carcinogen. Millions of people worldwide suffer from As toxicity due to the intake of As-contaminated drinking water and food. Reducing the As concentration in drinking water and food is thus of critical importance. Phytoremediation of soil contaminated with As and the reduction of As contamination in food depend on a detailed understanding of As uptake and transport in plants. As transporters play essential roles in As uptake, translocation and accumulation in plant cells. In this review, we summarize the current understanding of As transport in plants, with an emphasis on As uptake, mechanisms of As resistance and the long-distance translocation of As, especially the accumulation of As in grains through phloem-mediated transport. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. 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.

  10. Cuticular Hydrocarbons of Tribolium confusum Larvae Mediate Trail Following and Host Recognition in the Ectoparasitoid Holepyris sylvanidis.

    Science.gov (United States)

    Fürstenau, Benjamin; Hilker, Monika

    2017-09-01

    Parasitic wasps which attack insects infesting processed stored food need to locate their hosts hidden inside these products. Their host search is well-known to be guided by host kairomones, perceived via olfaction or contact. Among contact kairomones, host cuticular hydrocarbons (CHCs) may provide reliable information for a parasitoid. However, the chemistry of CHC profiles of hosts living in processed stored food products is largely unknown. Here we showed that the ectoparasitoid Holepyris sylvanidis uses CHCs of its host Tribolium confusum, a worldwide stored product pest, as kairomones for host location and recognition at short range. Chemical analysis of T. confusum larval extracts by gas chromatography coupled with mass spectrometry revealed a rich blend of long-chain (C25-C30) hydrocarbons, including n-alkanes, mono-, and dimethylalkanes. We further studied whether host larvae leave sufficient CHCs on a substrate where they walk along, thus allowing parasitoids to perceive a CHC trail and follow it to their host larvae. We detected 18 CHCs on a substrate that had been exposed to host larvae. These compounds were also found in crude extracts of host larvae and made up about a fifth of the CHC amount extracted. Behavioral assays showed that trails of host CHCs were followed by the parasitoids and reduced their searching time until successful host recognition. Host CHC trails deposited on different substrates were persistent for about a day. Hence, the parasitoid H. sylvanidis exploits CHCs of T. confusum larvae for host finding by following host CHC trails and for host recognition by direct contact with host larvae.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Actividad biológica de extractos de Melia azedarach sobre larvas de Spodoptera eridania (Lepidoptera: Noctuidae Biological activity of extracts of Melia azedarach on larvae of Spodoptera eridania (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    María R. Rossetti

    2008-06-01

    Full Text Available En la búsqueda de compuestos botánicos con potencial uso insecticida, se evaluó la actividad de extractos de fruto maduro y hojas senescentes de Melia azedarach L. (2, 5 y 10%, sobre larvas de Spodoptera eridania Cramer (Lepidoptera: Noctuidae especie polífaga considerada plaga esporádica de importantes cultivos. Mediante pruebas de elección, se registró el consumo y se calculó un índice de inhibición alimentaria. En pruebas sin posibilidad de elección se estimó el consumo, la mortalidad, el peso de larvas y excretas, y se calcularon índices nutricionales. Cuando las larvas pudieron optar, se observó un fuerte efecto antialimentario de los extractos. En los ensayos de alimentación obligada, los extractos de fruto y hoja redujeron fuertemente el consumo y peso larval respecto al control, excepto la menor dosis de fruto. Ninguna oruga llegó a pupar al entregarle alimento rociado con extracto de hoja o con extracto de fruto en las dosis más altas. Los índices nutricionales corroboraron la actividad antialimentaria, revelando efectos negativos de los extractos sobre las tasas relativas de consumo y crecimiento, y sobre la eficiencia de utilización del alimento ingerido y digerido, aunque la digestibilidad no fue afectada. Los resultados sugieren que los extractos de M. azedarach podrían ser incorporados en programas de manejo de este insecto plaga.In the course of searching for plant chemicals with potential insecticide properties, the activity of Melia azedarach L. senescent leaf and ripe fruit extracts (2, 5 and 10% was evaluated on larvae of Spodoptera eridania Cramer (Lepidoptera: Noctuidae. This polyphagous species is considered a sporadic pest on many important crops. Food consumption was assessed and an antifeedant index was calculated through choice tests. Also, food consumption, larval mortality, weight and depositions were recorded and nutritional indices were calculated in no-choice tests. Results from choice tests

  13. In vitro uptake and immune functionality of digested Rosemary extract delivered through food grade vehicles.

    Science.gov (United States)

    Arranz, E; Guri, A; Fornari, T; Mendiola, J A; Reglero, G; Corredig, M

    2017-07-01

    The digestion, absorption, uptake and bioavailability of a rosemary supercritical fluid extract encapsulated in oil in water emulsion were studied. Two emulsions with opposite surface charge were prepared, containing 7% canola oil, and either 2% lactoferrin or whey protein isolate. When absorption and uptake of carnosic acid and carnosol were followed on Caco-2 cell monolayers, there were no differences with protein type. However, when co-cultures of HT-29 MTX were employed, the presence of mucus caused a higher retention of carnosic acid in the apical layer for lactoferrin emulsions. The immune activity of the bioavailable fractions collected from cell absorption experiments was tested ex vivo on murine splenocytes. Although transport through the intestinal barrier models was low, the bioavailable fractions showed a significant effect on splenocytes proliferation. These results demonstrated the potential of using rosemary supercritical extract through protein stabilized oil in water emulsions, as a food with immunomodulatory functionality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Presence of parasitic ova, cysts and larva on common fresh fruits ...

    African Journals Online (AJOL)

    Several parasitic infections are associated with poor hygiene and environmental sanitation resulting in food and water containing ova, cysts or larva of these parasites. Therefore, a survey of fruits and vegetables sold at some major markets in Ibadan was carried out between January and June, 2011 to identify the ova, cyst ...

  15. Thromboxane plays a role in postprandial jejunal oxygen uptake and capillary exchange.

    Science.gov (United States)

    Alemayehu, A; Chou, C C

    1990-09-01

    The effects of a thromboxane A2 (TxA2)-endoperoxide receptor antagonist, SQ 29548, on jejunal blood flow, oxygen uptake, and capillary filtration coefficient (Kfc) were determined in anesthetized dogs under resting conditions and during the presence of predigested food in the jejunal lumen in three series of experiments. In series 1, 2.0 micrograms intra-arterial administration of SQ 29548 was found to abolish completely the vasoconstrictor action of graded doses (0.05-2.0 micrograms) of intra-arterial injection of a TxA2-endoperoxide analogue, U44069. SQ 29548 (2.0 micrograms ia) per se did not significantly alter resting jejunal blood flow, oxygen uptake, capillary pressure, or Kfc. Before SQ 29548, placement of food plus bile into the jejunal lumen increased blood flow +42 +/- 9%, oxygen uptake +28 +/- 7%, and Kfc +24 +/- 6%. After SQ 29548, the food placement increased blood flow +37 +/- 8%, oxygen uptake +52 +/- 11%, and Kfc +63 +/- 20%. The food-induced increases in oxygen uptake and Kfc after SQ 29548 were significantly greater than those induced before the blocking of TxA2-endoperoxide receptors by SQ 29548. Our study indicates that endogenous thromboxane does not play a role in regulating jejunal blood flow, capillary filtration, and oxygen uptake under resting conditions. However, it plays a role in limiting the food-induced increases in jejunal oxygen uptake and capillary exchange capacity without influencing the food-induced hyperemia.

  16. Safety assessment of freeze-dried powdered Tenebrio molitor larvae (yellow mealworm) as novel food source: Evaluation of 90-day toxicity in Sprague-Dawley rats.

    Science.gov (United States)

    Han, So-Ri; Lee, Byoung-Seok; Jung, Kyung-Jin; Yu, Hee-Jin; Yun, Eun-Young; Hwang, Jae Sam; Moon, Kyoung-Sik

    2016-06-01

    Worldwide demand for novel food source has grown and edible insects are a promising food sources for humans. Tenebrio molitor, as known as yellow mealworm, has advantages of being rich in protein, and easy to raise as a novel food source. The objective of this study was to evaluate subchronic toxicity, including potential hypersensitivity, of freeze-dried powdered T. molitor larvae (fdTML) in male and female Sprague-Dawley rats. The fdTML was administered orally once daily at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 90 days. A toxicological assessment was performed, which included mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings, histopathologic examination and allergic reaction. There were no fdTML- related findings in clinical signs, urinalysis, hematology and serum chemistry, gross examination, histopathologic examination or allergic reaction. In conclusion, the No Observed Adverse Effect Level (NOAEL) for fdTML was determined to be in excess of 3000 mg/kg/day in both sexes of rats under the experimental conditions of this study. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Changes in the amino acid profiles and free radical scavenging activities of Tenebrio molitor larvae following enzymatic hydrolysis.

    Science.gov (United States)

    Tang, Yujiao; Debnath, Trishna; Choi, Eun-Ju; Kim, Young Wook; Ryu, Jung Pyo; Jang, Sejin; Chung, Sang Uk; Choi, Young-Jin; Kim, Eun-Kyung

    2018-01-01

    Tenebrio molitor (T. molitor) larvae provide food at low environmental cost and contribute positively to livelihoods. In this research, we compared the amino acids compositions and antioxidant activities of various extracts of T. molitor to enhance their quality as food. For the comparison, distilled water extracts, enzymatic hydrolysates, and condensed enzymatic hydrolysates of T. molitor larvae were prepared. Their amino acids (AAs) profiles and antioxidant activities, including ferric-reducing antioxidant power, oxygen radical absorption capacity, and DPPH, hydroxyl radical, and hydrogen peroxide radical scavenging properties assay were analyzed. DW extracts had the lowest AAs contents and antioxidant activity compared with enzymatic extracts. Condensed hydrolysates with a combination of alcalase and flavourzyme (C-A+F) exhibited the highest levels of total free AAs (11.1759 g/100 g). C-A+F produced higher total hydrolyzed AAs (32.5292 g/100 g) compared with the other groups. The C-A+F possessed the strongest antioxidant activity. Notably, the antioxidant activities of the hydrolysates and the total hydrolyzed AAs amount were correlated. Taken together, our findings showed that C-A+F was a promising technique for obtaining extracts of T. molitor larvae with antioxidant activity as potential nutritious functional food.

  18. New method of preserving food

    Energy Technology Data Exchange (ETDEWEB)

    Carrard, G. (Australian Atomic Energy Commission Research Establishment, Lucas Heights)

    1983-07-01

    The use of gamma radiation for food preservation is discussed. Investigations at the AAEC include: the eradication of fruit-fly larvae in oranges, tomatoes and avocadoes; treatment of shrimps; extending the shelf life of mushrooms and potatoes; treatment of imported beans to prevent germination; killing of bacterial spores with a combination of pressure and gamma radiation; and the treatment of beehives containing honey-bee larvae with foulbrood.

  19. New method of preserving food

    International Nuclear Information System (INIS)

    Carrard, G.

    1983-01-01

    The use of gamma radiation for food preservation is discussed. Investigations at the AAEC include: the eradication of fruit-fly larvae in oranges, tomatoes and avocadoes; treatment of shrimps; extending the shelf life of mushrooms and potatoes; treatment of imported beans to prevent germination; killing of bacterial spores with a combination of pressure and gamma radiation; and the treatment of beehives containing honey-bee larvae with foulbrood

  20. Long Frontal Projections Help Battus philenor (Lepidoptera: Papilionidae) Larvae Find Host Plants.

    Science.gov (United States)

    Kandori, Ikuo; Tsuchihara, Kazuko; Suzuki, Taichi A; Yokoi, Tomoyuki; Papaj, Daniel R

    2015-01-01

    Animals sometimes develop conspicuous projections on or near their heads as, e.g., weaponry, burrowing or digging tools, and probes to search for resources. The frontal projections that insects generally use to locate and assess resources are segmented appendages, including antennae, maxillary palps, and labial palps. There is no evidence to date that arthropods, including insects, use projections other than true segmental appendages to locate food. In this regard, it is noteworthy that some butterfly larvae possess a pair of long antenna-like projections on or near their heads. To date, the function of these projections has not been established. Larvae of pipevine swallowtail butterflies Battus philenor (Papilionidae) have a pair of long frontal fleshy projections that, like insect antennae generally, can be actively moved. In this study, we evaluated the possible function of this pair of long moveable frontal projections. In laboratory assays, both frontal projections and lateral ocelli were shown to increase the frequency with which search larvae found plants. The frontal projections increased finding of host and non-host plants equally, suggesting that frontal projections do not detect host-specific chemical cues. Detailed SEM study showed that putative mechanosensillae are distributed all around the frontal as well as other projections. Taken together, our findings suggest that the frontal projections and associated mechanosensillae act as vertical object detectors to obtain tactile information that, together with visual information from lateral ocelli and presumably chemical information from antennae and mouthparts, help larvae to find host plants. Field observations indicate that host plants are small and scattered in southern Arizona locations. Larvae must therefore find multiple host plants to complete development and face significant challenges in doing so. The frontal projections may thus be an adaptation for finding a scarce resource before starving to

  1. Distribution patterns and feeding success of anchovy, Engraulis anchoita, larvae off southern Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo Cunha Vasconcellos

    1998-12-01

    Full Text Available Feeding success and changes in horizontal patchiness relative to size were studied for anchovy, Engraulis anchoita, larvae caught with a Bongo net off southern Brazil. Results show higher feeding success rates during winter, when the combined effect of enrichment, stability and retention mechanisms seems to create optimal conditions for larval feeding. Under optimal feeding conditions larvae of more than 10 mm have higher feeding success rates than smaller size classes. With a simple body structure and low swimming capabilities, larvae of up to 10 mm show a low level of patchiness, low evasion rate of the sampling gear and feeding on small food particles only. Results corroborate the hypothesis of a critical period between two important ontogenic phases: the beginning of exogenous feeding and the onset of active swimming, gas gland buoyancy and school forming behavior.

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

    Directory of Open Access Journals (Sweden)

    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. 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.

  4. 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).

  5. Intraguild predation among plant pests: western flower thrips larvae feed on whitefly crawlers

    NARCIS (Netherlands)

    van Maanen, R.; Broufas, G.; Oveja, M.F.; Sabelis, M.W.; Janssen, A.

    2012-01-01

    Omnivores obtain resources from more than one trophic level, and choose their food based on quantity and quality of these resources. For example, omnivores may switch to feeding on plants when prey are scarce. Larvae of the western flower thrips Frankiniella occidentalis Pergande (Thysanoptera:

  6. Research on Interrelationship between some Species of Freshwater Fish and Helmintic Larvae within Aquatic Ecosystems Polluted with Heavy Metals

    Directory of Open Access Journals (Sweden)

    Laura Daniela Urdeş

    2010-10-01

    Full Text Available The objective of this study was to investigate the ability of some larvae of cestodes and nematodes which live infreshwater fish (intermediate hosts, to exhibit an uptake of heavy metals.According to some scientifical papers treating this subject, only adult worms were able to absorb successfully heavymetals within their hosts. Furthermore, it is believed that only the adults would act as biofilters and consequently astrustworthy indicators of environmental pollution.This study, carried out on the Danube Delta area, comes to prove the ability of the larvae to absorb heavy metalswithin their hosts, even when the pollution level with respect to heavy metals is very low.Following the biochemical analyses of water, sediment, aquatic plants, larvae and fish tissues (liver and musclesamples, it resulted that the larvae were able to absorb important quantities within their hosts, so that only scarceamounts to be found in the muscle and liver. Both parasites were able to accumulate some heavy metals within theirhosts, although only one of them did it successfully.

  7. A production season of turbot larvae Scophthalmus maximus (Linnaeus, 1758) reared on copepods in a Danish (56 degrees N) semi-intensive outdoor system

    DEFF Research Database (Denmark)

    Jepsen, Per M.; Jakobsen, Hans H.; Rayner, Thomas A.

    2017-01-01

    Turbot were reared from yolk sack larvae to juvenile in an outdoor semi-intensive system. Three production cycles were monitored from May to September. A pelagic food chain was established with phytoplankton, copepods and turbot larvae. Abiotic and biotic parameters of lower trophic levels together...

  8. 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.

  9. Swim-training changes the spatio-temporal dynamics of skeletogenesis in zebrafish larvae (Danio rerio)

    NARCIS (Netherlands)

    Fiaz, A.W.; Leon-Kloosterziel, K.M.; Gort, G.; Schulte-Merker, S.; van Leeuwen, J.L.; Kranenbarg, S.

    2012-01-01

    Fish larvae experience many environmental challenges during development such as variation in water velocity, food availability and predation. The rapid development of structures involved in feeding, respiration and swimming increases the chance of survival. It has been hypothesized that mechanical

  10. 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.

  11. Impacts of weathered tire debris on the development of Rana sylvatica larvae.

    Science.gov (United States)

    Camponelli, Kimberly M; Casey, Ryan E; Snodgrass, Joel W; Lev, Steven M; Landa, Edward R

    2009-02-01

    Highway runoff has the potential to negatively impact receiving systems including stormwater retention ponds where highway particulate matter can accumulate following runoff events. Tire wear particles, which contain about 1% Zn by mass, make up approximately one-third of the vehicle derived particulates in highway runoff and therefore may serve as a stressor to organisms utilizing retention ponds as habitat. In this study, we focused on the potential contribution of tire debris to Zn accumulation by Rana sylvatica larvae and possible lethal or sublethal impacts resulting from exposure to weathered tire debris during development. Eggs and larvae were exposed to aged sediments (containing either ZnCl2 or tire particulate matter, both providing nominal concentrations of 1000 mg Zn kg(-1)) through metamorphosis. Water column Zn was elevated in both the ZnCl2 and tire treatments relative to the control treatment, indicating that aging allowed Zn leaching from tire debris to occur. Tissue Zn was also elevated for the ZnCl2 and tire treatments indicating that Zn in the treatments was available for uptake by the amphibians. Exposure to both ZnCl2 and tire treatments increased the time for larvae to complete metamorphosis in comparison with controls. We also observed that the longer the organisms took to complete metamorphosis, the smaller their mass at metamorphosis. Our results indicate that Zn leached from aged tire debris is bioavailable to developing R. sylvatica larvae and that exposure to tire debris amended sediments can result in measurable physiological outcomes to wood frogs that may influence population dynamics.

  12. Impacts of weathered tire debris on the development of Rana sylvatica larvae

    Science.gov (United States)

    Camponelli, K.M.; Casey, R.E.; Snodgrass, J.W.; Lev, S.M.; Landa, E.R.

    2009-01-01

    Highway runoff has the potential to negatively impact receiving systems including stormwater retention ponds where highway particulate matter can accumulate following runoff events. Tire wear particles, which contain about 1% Zn by mass, make up approximately one-third of the vehicle derived particulates in highway runoff and therefore may serve as a stressor to organisms utilizing retention ponds as habitat. In this study, we focused on the potential contribution of tire debris to Zn accumulation by Rana sylvatica larvae and possible lethal or sublethal impacts resulting from exposure to weathered tire debris during development. Eggs and larvae were exposed to aged sediments (containing either ZnCl2 or tire particulate matter, both providing nominal concentrations of 1000 mg Zn kg-1) through metamorphosis. Water column Zn was elevated in both the ZnCl2 and tire treatments relative to the control treatment, indicating that aging allowed Zn leaching from tire debris to occur. Tissue Zn was also elevated for the ZnCl2 and tire treatments indicating that Zn in the treatments was available for uptake by the amphibians. Exposure to both ZnCl2 and tire treatments increased the time for larvae to complete metamorphosis in comparison with controls. We also observed that the longer the organisms took to complete metamorphosis, the smaller their mass at metamorphosis. Our results indicate that Zn leached from aged tire debris is bioavailable to developing R. sylvatica larvae and that exposure to tire debris amended sediments can result in measurable physiological outcomes to wood frogs that may influence population dynamics. ?? 2008 Elsevier Ltd.

  13. 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.

  14. Combined use of gamma irradiation and the bioinsecticide, DIPEL 2X, in controlling larvae of the indian meal moth, ''Plodia interpunctella'' (Huebner) (''Lepidipthera phycitidae'')

    International Nuclear Information System (INIS)

    Ignatowicz, S.

    1996-01-01

    The bioinsecticide DIPEL 2X irradiated with doses of gamma radiation up to 2.0 kGy preserves its insecticidal efficiency against larvae of the Indian meal moth, ''Plodia interpunctella'' (Huebner). The amount of DIPEL 2X-treated food taken in by larvae irradiated with 0.1-0.7 kGy is sufficient for bringing about the death of these larvae. (author). 20 refs, 8 figs, 3 tabs

  15. Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from labelled seaweed (Chondrus crispus)

    International Nuclear Information System (INIS)

    Wilson, R.C.; Vives i Batlle, J.; McDonald, P.; Parker, T.G.

    2005-01-01

    Uptake and depuration experiments of 131 I from labelled seaweed (Chondrus crispus) by the edible periwinkle Littorina littorea have been performed. Radioiodine concentrations in winkles during uptake followed first-order kinetics with an uptake half-time of 1 day, and a calculated equilibrium concentration (C ∞ ) of 21 000 Bq kg -1 resulting in a transfer factor of 0.07 with respect to the labelled seaweed used as food. For depuration, a biphasic sequence with biological half-lives of 1 and 24 days was determined. The results suggest that in general, iodine turnover in periwinkles is slower than observed for other molluscs (monophasic biological half-lives in the order of 2-3 days). Both environmental media, food and seawater, can be significant sources of radioiodine for the winkle

  16. [Influence of lecithotrofic feeding on growth and development of larvae of freshwater shrimp Macrobrachium rosenbergii].

    Science.gov (United States)

    Borisov, R R; Kriakhova, N V

    2011-01-01

    In the giant freshwater shrimp Macrobrachium rosenbergii (De Man), lecithotrofic feeding was discovered at the zoea I stage, and facultative lecithotrofic feeding was found at the zoea II stage. Cases of the completion of the first two stages without feeding were detected. However, a delay in feeding at the zoea II stage caused the inhibition of the growth and development of larvae. In this connection, we recommend to introduce food to the aquaculture of the giant freshwater shrimp on the end of the first day after hatching, when the first zoea II larvae emerge.

  17. Prediction of acute toxicity of cadmium and lead to zebrafish larvae by using a refined toxicokinetic-toxicodynamic model

    International Nuclear Information System (INIS)

    Gao, Yongfei; Feng, Jianfeng; Zhu, Lin

    2015-01-01

    Highlights: • We developed a BLM-aided TK-TD model that considers the effects of H"+. • The time-course metal concentration in larvae was well described by the TK model. • The time-course survival of zebrafish larvae was well simulated by the TD model. - Abstract: The biotic ligand model (BLM) and the toxicokinetic-toxicodynamic (TK-TD) model are essential in predicting the acute toxicity of metals in various species and exposure conditions; however, these models are usually separately utilized. In this study, a mechanistic TK-TD model was developed to predict the acute toxicity of 10"−"6 M Cd and 10"−"6 M Pb to zebrafish (Danio rerio) larvae. The novel approach links the BLM with relevant TK processes to simulate the bioaccumulation processes of Cd or Pb as a function of the maximum uptake rate of each metal, the affinity constants, and the concentrations of free metal ions and H"+ in test solutions. Results showed that the refined TK-TD model can accurately predict the accumulation and acute toxicity of Cd and Pb to zebrafish larvae at pH 5.5, 6.5, and 7.0.

  18. Prediction of acute toxicity of cadmium and lead to zebrafish larvae by using a refined toxicokinetic-toxicodynamic model

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yongfei; Feng, Jianfeng, E-mail: fengjf@nankai.edu.cn; Zhu, Lin, E-mail: zhulin@nankai.edu.cn

    2015-12-15

    Highlights: • We developed a BLM-aided TK-TD model that considers the effects of H{sup +}. • The time-course metal concentration in larvae was well described by the TK model. • The time-course survival of zebrafish larvae was well simulated by the TD model. - Abstract: The biotic ligand model (BLM) and the toxicokinetic-toxicodynamic (TK-TD) model are essential in predicting the acute toxicity of metals in various species and exposure conditions; however, these models are usually separately utilized. In this study, a mechanistic TK-TD model was developed to predict the acute toxicity of 10{sup −6} M Cd and 10{sup −6} M Pb to zebrafish (Danio rerio) larvae. The novel approach links the BLM with relevant TK processes to simulate the bioaccumulation processes of Cd or Pb as a function of the maximum uptake rate of each metal, the affinity constants, and the concentrations of free metal ions and H{sup +} in test solutions. Results showed that the refined TK-TD model can accurately predict the accumulation and acute toxicity of Cd and Pb to zebrafish larvae at pH 5.5, 6.5, and 7.0.

  19. 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)

  20. Benthic food webs support the production of sympatric flatfish larvae in estuarine nursery habitat

    Science.gov (United States)

    Identifying nursery habitats is of paramount importance to define proper management and conservation strategies for flatfish species. Flatfish nursery studies usually report upon habitat occupation, but few attempted to quantify the importance of those habitats to larvae developm...

  1. Uptake of cobalt-60 from sea water and from labelled food by the common shrimp Crangon erangon (L.)

    International Nuclear Information System (INIS)

    Weers, A.W. van

    1975-01-01

    The role of two different modes of uptake in the accumulation of 60 Co by the common shrimp (Crangon crangon (L.)) is the subject of the present study. The results show that accumulation of 60 Co from sea water is a slow process. The concentration factor for whole animals reached in one month was only about 13. Most of the activity accumulated from water appears to be associated with the exoskeleton. As a consequence, moulting has a pronounced effect on the uptake pattern of 60 Co and on the subsequent retention of the radionuclide by shrimps kept in non-radioactive sea water. After single feeding of shrimps with labelled mussel flesh, 60 Co is retained according to an exponential function with a short-lived and a long-lived component. The short-lived component has a mean biological half-life of 1.2 days and accounts for about 80% of the initial activity. About 20% of the initial activity is lost with a mean biological half-life of about 10 days. After repeated feeding of labelled mussel flesh the short-lived component in the 60 Co retention is virtually absent. Cobalt-60 taken up with food is localized mainly in the digestive gland and the concentration in the edible muscles from the abdomen is relatively small. It is concluded from the present study that direct uptake from sea water will play only a minor role in the accumulation of 60 Co in the internal organs of the shrimp. 60 Co released into the marine environment will be taken up by shrimps mainly from food. The results indicate a rapid turnover of 60 Co in shrimps. (author)

  2. Optimizing the co-feeding strategy of Persian sturgeon (Acipenser persicus larvae using Artemia nauplii and formulated diet

    Directory of Open Access Journals (Sweden)

    Naser Agh

    2013-07-01

    Full Text Available High mortality and labor costs are associated with first-feeding sturgeon culture, particularly during the period of dietary transition from live to formulated feed. Therefore we investigated the effects of various feeding treatments on the survival and growth of the Persian sturgeon (Acipenser persicus larvae during a 20-day culture period. Three replicate groups (250 fish/replicate of first-feeding larvae were fed according to four main feeding regimes: (1 live food (live nauplii of brine shrimp Artemia urmiana; (2 indirect transition (5 days live food followed by gradual transition to formulated diet; (3 direct transition (using different combinations of live and formulated diet from the start feeding onwards; (4 formulated feed (FD from the start feeding. Results indicated that growth and survival were higher in the indirect transition feeding regime than in other regimes. Based on our study, co-feeding of A. persicus should start five days after prior feeding with live food.

  3. Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.

    Directory of Open Access Journals (Sweden)

    Raúl Laiz-Carrión

    Full Text Available The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C as trophic indicators for Atlantic bluefin tuna larvae (BFT (6-10 mm standard length in the highly contrasting environmental conditions of the Gulf of Mexico (GOM and the Balearic Sea (MED. These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.

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

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    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

  5. Opposite Effects of the Spinach Food Matrix on Lutein Bioaccessibility and Intestinal Uptake Lead to Unchanged Bioavailability Compared to Pure Lutein.

    Science.gov (United States)

    Margier, Marielle; Buffière, Caroline; Goupy, Pascale; Remond, Didier; Halimi, Charlotte; Caris-Veyrat, Catherine; Borel, Patrick; Reboul, Emmanuelle

    2018-06-01

    Food matrix is generally believed to alter carotenoid bioavailability, but its effect on xanthophylls is usually limited. This study thus aims to decipher the digestion-absorption process of lutein in the presence or not of a food matrix. Lutein transfer to gastric-like lipid droplets or artificial mixed micelles was assessed when lutein was added to test meals either as a pure molecule ((all-E)-lutein) or in canned spinach ((Z) + (all-E)-lutein). The obtained mixed micelles were delivered to Caco-2 cells to evaluate lutein uptake. Finally postprandial plasma lutein responses were compared in minipigs after the two test meals. Lutein transfer to gastric-like lipid droplets and to mixed micelles was higher when lutein was added in spinach than when it was added as pure lutein (+614% and +147%, respectively, p < 0.05). Conversely, lutein uptake was less effective when micellar lutein was from a meal containing spinach than from a meal containing its pure form (-55%, p < 0.05). In minipigs, postprandial lutein response was delayed with spinach but not significantly different after the two test meals. Opposite effects at the micellarization and intestinal cell uptake steps explain the lack of effect of spinach matrix on lutein bioavailability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. 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.

  7. Sodium benzoate induced developmental defects, oxidative stress and anxiety-like behaviour in zebrafish larva.

    Science.gov (United States)

    Gaur, Himanshu; Purushothaman, Srinithi; Pullaguri, Narasimha; Bhargava, Yogesh; Bhargava, Anamika

    2018-05-28

    Sodium benzoate (SB) is a common food preservative. Its FDA described safety limit is 1000 ppm. Lately, increased use of SB has prompted investigations regarding its effects on biological systems. Data regarding toxicity of SB is divergent and controversial with studies reporting both harmful and beneficial effects. Therefore, we did a systematic dose dependent toxicity study of SB using zebrafish vertebrate animal model. We also investigated oxidative stress and anxiety-like behaviour in zebrafish larva treated with SB. Our results indicate that SB induced developmental (delayed hatching), morphological (pericardial edema, yolk sac edema and tail bending), biochemical (oxidative stress) and behavioural (anxiety-like behaviour) abnormalities in developing zebrafish larva. LC 50 of SB induced toxicity was approximately 400 ppm after 48 h of SB exposure. Our study strongly supports its harmful effects on vertebrates at increasing doses. Thus, we suggest caution in the excessive use of this preservative in processed and convenience foods. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. 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...

  9. Coral larvae for restoration and research: a large-scale method for rearing Acropora millepora larvae, inducing settlement, and establishing symbiosis

    Directory of Open Access Journals (Sweden)

    F. Joseph Pollock

    2017-09-01

    Full Text Available Here we describe an efficient and effective technique for rearing sexually-derived coral propagules from spawning through larval settlement and symbiont uptake with minimal impact on natural coral populations. We sought to maximize larval survival while minimizing expense and daily husbandry maintenance by experimentally determining optimized conditions and protocols for gamete fertilization, larval cultivation, induction of larval settlement by crustose coralline algae, and inoculation of newly settled juveniles with their dinoflagellate symbiont Symbiodinium. Larval rearing densities at or below 0.2 larvae mL−1 were found to maximize larval survival and settlement success in culture tanks while minimizing maintenance effort. Induction of larval settlement via the addition of a ground mixture of diverse crustose coralline algae (CCA is recommended, given the challenging nature of in situ CCA identification and our finding that non settlement-inducing CCA assemblages do not inhibit larval settlement if suitable assemblages are present. Although order of magnitude differences in infectivity were found between common Great Barrier Reef Symbiodinium clades C and D, no significant differences in Symbiodinium uptake were observed between laboratory-cultured and wild-harvested symbionts in each case. The technique presented here for Acropora millepora can be adapted for research and restoration efforts in a wide range of broadcast spawning coral species.

  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

    2018-06-01

    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.

  11. 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.

  12. Caenorhabditis elegans battling starvation stress: low levels of ethanol prolong lifespan in L1 larvae.

    Directory of Open Access Journals (Sweden)

    Paola V Castro

    Full Text Available The nematode Caenorhabditis elegans arrests development at the first larval stage if food is not present upon hatching. Larvae in this stage provide an excellent model for studying stress responses during development. We found that supplementing starved larvae with ethanol markedly extends their lifespan within this L1 diapause. The effects of ethanol-induced lifespan extension can be observed when the ethanol is added to the medium at any time between 0 and 10 days after hatching. The lowest ethanol concentration that extended lifespan was 1 mM (0.005%; higher concentrations to 68 mM (0.4% did not result in increased survival. In spite of their extended survival, larvae did not progress to the L2 stage. Supplementing starved cultures with n-propanol and n-butanol also extended lifespan, but methanol and isopropanol had no measurable effect. Mass spectrometry analysis of nematode fatty acids and amino acids revealed that L1 larvae can incorporate atoms from ethanol into both types of molecules. Based on these data, we suggest that ethanol supplementation may extend the lifespan of L1 larvae by either serving as a carbon and energy source and/or by inducing a stress response.

  13. Aflatoxin B1 Tolerance and Accumulation in Black Soldier Fly Larvae (Hermetia illucens) and Yellow Mealworms (Tenebrio molitor).

    Science.gov (United States)

    Bosch, Guido; Fels-Klerx, H J van der; Rijk, Theo C de; Oonincx, Dennis G A B

    2017-06-02

    Crops contaminated with fungal mycotoxins such as aflatoxin B1 (AFB1) are often downgraded or removed from the food chain. This study aimed to evaluate the tolerance and accumulation of AFB1 in two insect species to determine whether they could be used to retain condemned mycotoxin contaminated crops in the food chain. First, instar black soldier fly larvae ( Hermetia illucens , BSF) and yellow mealworm ( Tenebrio molitor , YMW) were fed poultry feed spiked with AFB1 and formulated to contain levels of 0.01, 0.025, 0.05, 0.10, 0.25, and up to 0.5 mg/kg dry feed. Poultry feed without any additions and feed with only the solvent added served as controls. The AFB1 in the feed did not affect survival and body weight in the BSF and YMW larvae ( p > 0.10), indicating a high tolerance to aflatoxin B1 in both species. Furthermore, AFB1 and aflatoxin M1 (AFM1) were below the detection limit (0.10 µg/kg) in BSF larvae, whereas the YMW had AFB1 levels that were approximately 10% of the European Union's legal limit for feed materials and excreted AFM1. It is concluded that both BSF larvae and YMW have a high AFB1 tolerance and do not accumulate AFB1.

  14. Evaluating penetration ability of Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) larvae into multilayer polypropylene packages

    Science.gov (United States)

    Larvae of the Indian meal moth, Plodia interpunctella (Hübner), can invade or penetrate packaging materials and infest food products. Energy bars with three polypropylene packaging types were challenged with eggs (first instars), third, and fifth instars of P. interpunctella to determine package res...

  15. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    Seo, Minchul; Goo, Tae-Won; Chung, Mi Yeon; Baek, Minhee; Hwang, Jae-Sam; Kim, Mi-Ae; Yun, Eun-Young

    2017-02-28

    Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor , the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90%) upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP)-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  16. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Minchul Seo

    2017-02-01

    Full Text Available Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor, the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90% upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  17. Impact of substrate contamination with mycotoxins, heavy metals and pesticides on the growth performance and composition of black soldier fly larvae (Hermetia illucens) for use in the feed and food value chain.

    Science.gov (United States)

    Purschke, Benedict; Scheibelberger, Rafaela; Axmann, Sonja; Adler, Andreas; Jäger, Henry

    2017-08-01

    Edible insects have emerged as an alternative and sustainable source of high-quality, animal-derived protein and fat for livestock production or direct human nutrition. During the production of insects, substrate quality is a key parameter to assure optimal insect biomass gain as well as the safety of feed and food derived from commercially reared insects. Therefore, the influence of a realistic substrate contamination scenario on growth performance and accumulation behaviour of black soldier fly larvae (BSFL; Hermetia illucens L.) was investigated. Newly hatched larvae were fed on a corn-based substrate spiked with heavy metals (As, Cd, Cr, Hg, Ni, Pb), mycotoxins (aflatoxins B1/B2/G2, deoxynivalenol, ochratoxin A, zearalenone) and pesticides (chlorpyrifos, chlorpyrifos-methyl, pirimiphos-methyl) under defined breeding conditions (10 days, 28°C, 67% relative humidity). The extent of contaminants' bioaccumulation in the larval tissue as well as the effect on growing determinants were examined. The applied heavy metal substrate contamination was shown to impair larval growing indicated by significantly lower post-trial larval mass and feed conversion ratio (FCR). Cd and Pb accumulation factors of 9 and 2, respectively, were determined, while the concentrations of other heavy metals in the larvae remained below the initial substrate concentration. In contrast, mycotoxins and pesticides have neither been accumulated in the larval tissue nor significantly affected the growing determinants in comparison with the control. The use of BSFL as livestock feed requires contaminant monitoring - especially for Cd and Pb - in the substrates as well as in feedstuff containing BSFL to ensure feed and food safety along the value chain.

  18. Produção de pós-larvas de Macrobrachium amazonicum (Heller, 1862 (Decapoda, Palaemonidae, sob condições controladas de laboratório

    Directory of Open Access Journals (Sweden)

    Aline Do Vale Barreto

    1982-01-01

    Full Text Available Studies on production of post-larvae of the prawn Macrobrachium amazonicum under controlled laboratory conditions were developed at the Departamento de Oceanografia da Universidade Federal de Pernambuco, from September 1980 to February 1982. Experiments were undertaken in aquaria and tanks where the salinity and density of the populations had been changed. The best production was obtained with salinity 14/00 with a density of 38 larvae per litre. The food provided for larvae was crushed fish and nauplii of Artemia salina. Out of 13 experiments a total of 20,000 post-larvae of Macrobrachium amazonicum were obtained.

  19. 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

  20. 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

  1. 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.

  2. Effects of crushed conspecifics on growth and survival of Penaeus monodon Fabricius post larvae

    NARCIS (Netherlands)

    Nga, B.T.; Lürling, M.F.L.L.W.; Peeters, E.T.H.M.; Roijackers, R.M.M.; Scheffer, M.; Nghia, T.T.

    2006-01-01

    In the present study, the hypothesis tested was that Penaeus monodon post-larvae (PL) experience lower growth when exposed to crushed conspecifics, which was achieved by exposing individual P. monodon PL with abundant food for 4 weeks to a gradient from 0 to 100 crushed conspecific PL L1. Both dry

  3. Root uptake of transuranic elements

    International Nuclear Information System (INIS)

    Schulz, R.K.

    1977-01-01

    The uptake of elements by plant roots is one of the important pathways of entry of many elements into the food chain of man. Data are cited showing plutonium concentration ratios, plant/soil, ranging from 10 -10 to 10 -3 . Concentration ratios for americium range from 10 -7 to 10 +1 . Limited experiments with curium and neptunium indicate that root uptake of curium is similar to that of americium and that plant uptake of neptunium is substantially larger than that of curium and americium. The extreme ranges of concentration ratios cited for plutonium and americium are due to a number of causes. Experimental conditions such as very intensive cropping will lead to abnormally high concentration ratios. In some experiments, addition of chelating agents markedly increased plant root uptake of transuranic elements. Particle size and composition of the source material influenced uptake of the transuranics by plants. Translocation within the plant, and soil factors such as pH and organic matter content, all affect concentration ratios

  4. 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.

  5. Optimised selenium enrichment of Artemia sp. feed to improve red drum (Sciaenops ocellatus) larvae rearing.

    Science.gov (United States)

    Juhász, Péter; Lengyel, Szvetlana; Udvari, Zsolt; Sándor, Alex Nagy; Stündl, László

    2017-09-01

    Selenium is an essential microelement for the normal functioning of life processes. Moreover, it is a component of enzymes with antioxidant effects. However, it has the smallest window of any micronutrient between requirement and toxicity. Selenium is a regularly used element in fish feeds; moreover, enriching zooplankton with selenium to rear larvae is also a well-known technology. It is accepted that the most common starter foods of fish larvae, natural rotifers contain the smallest dosage of selenium, but providing selenium enriched Artemia sp. instead could increase survival and growth rate of fish. However, no such references are available for the red drum (Sciaenops ocellatus) larvae. Therefore, in this study, Artemia sp. was enriched with nano-selenium of verified low toxicity and easy availability in 5 treatments (1, 5, 10, 50, 100 mg/l Se), and then, fish larvae were fed with four of these enriched Artemia stocks (1, 5, 10, 50 mg/l Se) and a control group. At the end of the 9-day-long experiment, survival rate (S) and growth parameters (SL, W, K-factor, SGR) of fish larvae were calculated as well as their selenium retention and glutathione peroxidase enzyme activity were analysed. It was revealed that a moderate level of selenium enrichment (~4 mg/kg dry matter) of Artemia sp. positively influences the rearing efficiency (i.e. survival and growth) of fish larvae, but higher dosages of selenium could cause adverse effects.

  6. Extreme morphologies of mantis shrimp larvae

    Directory of Open Access Journals (Sweden)

    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.

  7. Development of digestive enzymes in larvae of Mayan cichlid Cichlasoma urophthalmus.

    Science.gov (United States)

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

    2011-03-01

    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 to 60 dah. Most digestive enzymes were present from yolk absorption (5-6 dah), except for the specific acid proteases activity (pepsin-like), which increase rapidly from 8 dah up to 20 dah. Three alkaline proteases isoforms (24.0, 24.8, 84.5 kDa) were detected at 8 dah using SDS-PAGE zymogram, corresponding to trypsin, chymotrypsin and probably leucine aminopeptidase enzymes, and only one isoform was detected (relative electromobility, Rf = 0.54) for acid proteases (pepsin-like) from 3 dah onwards using PAGE zymogram. We concluded that C. urophthamus is a precocious fish with a great capacity to digest all kinds of food items, including artificial diets provided from 13 dah.

  8. Rearing larvae of dusky grouper, Epinephelus marginatus (Lowe, 1834, (Pisces: Serranidae in a semi-extensive mesocosm

    Directory of Open Access Journals (Sweden)

    Maria Emília Cunha

    2009-10-01

    Full Text Available One of the major obstacles to propagating dusky grouper, Epinephelus marginatus, is the difficulty of rearing the early larvae. We have successfully raised dusky grouper larvae in mesocosms using a mixed diet of endogenous plankton grown in the rearing tank and an exogenous supply of Brachionus plicatilis and Artemia sp. Newly hatched larvae at an initial density of 1.3 ind.l-1 were stocked in partially shaded 3 m3 circular outdoor tanks during the summers of 2007 and 2008. Before introducing newly hatched larvae, the water was left for six days to promote plankton growth. Larval growth occurred at two different rates: i a faster rate from first feeding to the beginning of metamorphosis, and ii a slower rate at transformation. Survival at the beginning of metamorphosis was less than 10% (33 DPH in 2007 and between 25 and 50% (25 DPH in 2008. High mortalities were observed during larval transformation. The estimated minimum food requirement per grouper larvae increased more than 300% from the beginning of the notochord flexion to the beginning of metamorphosis. To meet such a high feeding requirement the number of larger prey organisms/copepods in the mesocosm should be eight times higher during this time period.

  9. Abrupt change in food environment induces cloning in plutei of Dendraster excentricus.

    Science.gov (United States)

    McDonald, Kathryn A; Vaughn, Dawn

    2010-08-01

    Asexual reproduction, or cloning, of planktonic echinoderm larvae has been observed in the laboratory and in nature, but little is known about its ecology. Here we examine the effects of algal food density and of a change in food density on the incidence of cloning in larvae of the sand dollar Dendraster excentricus. Results indicate that a change in food concentration can induce cloning in plutei. Cultures transferred from a low to a high algal ration at the time when primary larvae were developing the third (posterodorsal) pair of larval arms showed decreased postoral arm length, unusual morphologies, and increased larval density in culture. These dense cultures of smaller plutei were produced within 48 h of the food pulse. The result is consistent with the occurrence of a burst of cloning, possibly through anterior autotomization. A second feeding experiment demonstrated that anterior autotomization does occur in 4- to 6-arm plutei. Rather than constituting a developmental rarity, cloning may happen early and often in D. excentricus cohorts when environmental conditions favor rapid growth.

  10. 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.

  11. A pair of pharyngeal gustatory receptor neurons regulates caffeine-dependent ingestion in Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Jaekyun Choi

    2016-07-01

    Full Text Available The sense of taste is an essential chemosensory modality that enables animals to identify appropriate food sources and control feeding behavior. In particular, the recognition of bitter taste prevents animals from feeding on harmful substances. Feeding is a complex behavior comprised of multiple steps, and food quality is continuously assessed. We here examined the role of pharyngeal gustatory organs in ingestion behavior. As a first step, we constructed a gustatory receptor-to-neuron map of the larval pharyngeal sense organs, and examined corresponding gustatory receptor neuron projections in the larval brain. Out of 22 candidate bitter compounds, we found 14 bitter compounds that elicit inhibition of ingestion in a dose-dependent manner. We provide evidence that certain pharyngeal gustatory receptor neurons are necessary and sufficient for the ingestion response of larvae to caffeine. Additionally, we show that a specific pair of pharyngeal gustatory receptor neurons, DP1, responds to caffeine by calcium imaging. In this study we show that a specific pair of gustatory receptor neurons in the pharyngeal sense organs coordinates caffeine sensing with regulation of behavioral responses such as ingestion. Our results indicate that in Drosophila larvae, the pharyngeal gustatory receptor neurons have a major role in sensing food palatability to regulate ingestion behavior. The pharyngeal sense organs are prime candidates to influence ingestion due to their position in the pharynx, and they may act as first level sensors of ingested food.

  12. The impact of the adult blue mussel (Mytilus edulis) population on settling of conspecific larvae

    DEFF Research Database (Denmark)

    Dolmer, Per; Stenalt, Ea

    2010-01-01

    The choice of a mussel bed as a settling locality by conspecific mussel larvae is a trade-off between reduced fitness due to an increased risk of larval predation and post-settling food competition with the filtering adults and the benefit from a reduced post-settling mortality. This reduced post...

  13. Chemical form of plutonium in foodstuffs - its influence on gastro-intestinal uptake

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, J.R. (National Radiological Protection Board, Harwell (UK))

    1984-01-01

    A brief review is given of some studies of the chemical form of plutonium in food eaten by man and how this may influence gastrointestinal uptake. Phytate ligands, present in many foods, bind strongly to plutonium. High levels of enzyme phytase in rat intestines enhance the gastrointestinal uptake of plutonium phytate in rats compared to rabbits. Taking into account 1) the low levels of phytase in human intestine and 2) the possibility of competing precipitation reactions, it would seem unlikely that the phytate-mediated elevation of plutonium uptake seen in rats will apply to humans.

  14. Molecular identification and food source inference of constructive ...

    African Journals Online (AJOL)

    Ophiocordyceps sinensis is a precious and effectual Traditional Chinese Medicine, native to Tibetan Plateau. Its development originated from parasitization of Hirsutella sinensis to Hepialus larvae, which was deemed to be of great importance including feeding food habit. Hereby in the present, study on food resource ...

  15. Visceral larvae as a predictive index of the overall level of fish batch infection in European anchovies (Engraulis encrasicolus): A rapid procedure for Food Business Operators to assess marketability.

    Science.gov (United States)

    Guardone, L; Nucera, D; Pergola, V; Costanzo, F; Costa, E; Tinacci, L; Guidi, A; Armani, A

    2017-06-05

    The European anchovy (Engraulis encrasicolus), one of the most important pelagic fish resources in the Mediterranean Sea, is frequently infected by anisakid larvae. Food Business Operators (FBOs) should use appropriate sampling plans and analytical methods to avoid commercialization of massively infected batches and reduce the risk of transmission of viable zoonotic larvae. In this study, performed at FishLab (Department of Veterinary Sciences of the University of Pisa) during 2016, an official sampling plan was associated with a digestion protocol for the inspection of anchovies. Considering that anisakid larvae are usually located in the fish visceral cavity and in the adjacent muscles (VM), this part was analyzed. In particular, we assessed the reliability of the digestion of a subsample of 150g (±30g) of VM, randomly collected from 29 specimens, in estimating the marketability of the anchovies' batch. Fifty-seven samples of 29 anchovies were collected. Each anchovy was sectioned to separate VM. All the subsamples were digested, and visible larvae counted. A high correlation between the number of larvae in VM regions and in the total batch was observed, indicating a very significant contribution of the VM region on total number of parasites. The Mean Abundance (MA) was used to assess the batch marketability according to a threshold calculated on the basis of the maximum number of nematodes tolerated per sample. Considering that the MA can be calculated only when the number of examined specimens is known, the number of visible Larvae per gram of tissue (LpG) was calculated on 150g (±30g) of VM subsamples. A LpG marketability threshold was calculated dividing the maximum number of tolerated nematodes by the average weight of a sample of 29 anchovies calculated considering data available in literature. To evaluate the diagnostic performance of the LpG threshold, the marketability of 57 batches assessed on the basis of the MA threshold was assumed as the gold

  16. Larvas output and influence of human factor in reliability of meat inspection by the method of artificial digestion

    Directory of Open Access Journals (Sweden)

    Đorđević Vesna

    2013-01-01

    Full Text Available On the basis of the performed analyses of the factors that contributed the infected meat reach food chain, we have found out that the infection occurred after consuming the meat inspected by the method of collective samples artificial digestion by using a magnetic stirrer (MM. In this work there are presented assay results which show how modifications of the method, on the level of final sedimentation, influence the reliability of Trichinella larvas detection in the infected meat samples. It has been shown that use of inadequate laboratory containers for larva collecting in final sedimentation and change of volume of digestive liquid that outflow during colouring preparations, can significantly influence inspection results. Larva detection errors ranged from 4 to 80% in presented the experimental groups in regard to the control group of samples inspected by using MM method, which had been carried out completely according to Europe Commission procedure No 2075/2005, where no errors in larva number per sample was found. We consider that the results of this work will contribute to the improvement of control of the method performance and especially of the critical point during inspection of meat samples to Trichinella larvas in Serbia.

  17. Biology and nutrition of Spodoptera frugiperda (Lepidoptera: Noctuidae fed on different food sources

    Directory of Open Access Journals (Sweden)

    Débora Mello da Silva

    Full Text Available ABSTRACT: We studied Spodoptera frugiperda development using different food sources in the laboratory and field. Newly hatched larvae were fed soybean, cotton, maize, wheat, and oat leaves. An artificial diet was used as the control. Duration of pre-pupal, pupal, and larva-adult period, pupal weight, sex ratio, survival, larva feeding preferences, oviposition preferences, and nutritional quality of different hosts were evaluated. Insects fed on wheat showed the shortest larva-adult period. The insects fed on cotton and soybean had longer larval development cycles and pupae of lower weight. Feeding preference was evident for third instar larvae and did not differ between wheat, oat, maize, and soybean, which were the preferred hosts. Moths oviposited to a greater extent on the upper canopy of wheat than that of other plants in both the no-choice and free-choice tests. Treatments influenced insect growth, food consumption, and digestion when nutritional variables were analyzed. Thus, grasses were better hosts for S. frugiperda development. Cotton was the least preferred food, followed by soybean. The present study can improve our understanding of S. frugiperda in these different crops and help in developing management strategies. Even though S. frugiperda is considered to be polyphagous, this pest is closely associated with grasses (maize, wheat, oat and has lower potential as a soybean or cotton feeder. Howerver, S. frugiperda food intake regulation appears to be triggered by a complex of different mechanisms. Thus, S. frugiperda can also damage soybean and cotton and adapt to them in the absence of preferred hosts.

  18. 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.

  19. Effect of fungal colonization of wheat grains with Fusarium spp. on food choice, weight gain and mortality of meal beetle larvae (Tenebrio molitor.

    Directory of Open Access Journals (Sweden)

    Zhiqing Guo

    Full Text Available Species of Fusarium have significant agro-economical and human health-related impact by infecting diverse crop plants and synthesizing diverse mycotoxins. Here, we investigated interactions of grain-feeding Tenebrio molitor larvae with four grain-colonizing Fusarium species on wheat kernels. Since numerous metabolites produced by Fusarium spp. are toxic to insects, we tested the hypothesis that the insect senses and avoids Fusarium-colonized grains. We found that only kernels colonized with F. avenaceum or Beauveria bassiana (an insect-pathogenic fungal control were avoided by the larvae as expected. Kernels colonized with F. proliferatum, F. poae or F. culmorum attracted T. molitor larvae significantly more than control kernels. The avoidance/preference correlated with larval feeding behaviors and weight gain. Interestingly, larvae that had consumed F. proliferatum- or F. poae-colonized kernels had similar survival rates as control. Larvae fed on F. culmorum-, F. avenaceum- or B. bassiana-colonized kernels had elevated mortality rates. HPLC analyses confirmed the following mycotoxins produced by the fungal strains on the kernels: fumonisins, enniatins and beauvericin by F. proliferatum, enniatins and beauvericin by F. poae, enniatins by F. avenaceum, and deoxynivalenol and zearalenone by F. culmorum. Our results indicate that T. molitor larvae have the ability to sense potential survival threats of kernels colonized with F. avenaceum or B. bassiana, but not with F. culmorum. Volatiles potentially along with gustatory cues produced by these fungi may represent survival threat signals for the larvae resulting in their avoidance. Although F. proliferatum or F. poae produced fumonisins, enniatins and beauvericin during kernel colonization, the larvae were able to use those kernels as diet without exhibiting increased mortality. Consumption of F. avenaceum-colonized kernels, however, increased larval mortality; these kernels had higher enniatin

  20. Effect of Fungal Colonization of Wheat Grains with Fusarium spp. on Food Choice, Weight Gain and Mortality of Meal Beetle Larvae (Tenebrio molitor)

    Science.gov (United States)

    Guo, Zhiqing; Döll, Katharina; Dastjerdi, Raana; Karlovsky, Petr; Dehne, Heinz-Wilhelm; Altincicek, Boran

    2014-01-01

    Species of Fusarium have significant agro-economical and human health-related impact by infecting diverse crop plants and synthesizing diverse mycotoxins. Here, we investigated interactions of grain-feeding Tenebrio molitor larvae with four grain-colonizing Fusarium species on wheat kernels. Since numerous metabolites produced by Fusarium spp. are toxic to insects, we tested the hypothesis that the insect senses and avoids Fusarium-colonized grains. We found that only kernels colonized with F. avenaceum or Beauveria bassiana (an insect-pathogenic fungal control) were avoided by the larvae as expected. Kernels colonized with F. proliferatum, F. poae or F. culmorum attracted T. molitor larvae significantly more than control kernels. The avoidance/preference correlated with larval feeding behaviors and weight gain. Interestingly, larvae that had consumed F. proliferatum- or F. poae-colonized kernels had similar survival rates as control. Larvae fed on F. culmorum-, F. avenaceum- or B. bassiana-colonized kernels had elevated mortality rates. HPLC analyses confirmed the following mycotoxins produced by the fungal strains on the kernels: fumonisins, enniatins and beauvericin by F. proliferatum, enniatins and beauvericin by F. poae, enniatins by F. avenaceum, and deoxynivalenol and zearalenone by F. culmorum. Our results indicate that T. molitor larvae have the ability to sense potential survival threats of kernels colonized with F. avenaceum or B. bassiana, but not with F. culmorum. Volatiles potentially along with gustatory cues produced by these fungi may represent survival threat signals for the larvae resulting in their avoidance. Although F. proliferatum or F. poae produced fumonisins, enniatins and beauvericin during kernel colonization, the larvae were able to use those kernels as diet without exhibiting increased mortality. Consumption of F. avenaceum-colonized kernels, however, increased larval mortality; these kernels had higher enniatin levels than F

  1. Effect of fungal colonization of wheat grains with Fusarium spp. on food choice, weight gain and mortality of meal beetle larvae (Tenebrio molitor).

    Science.gov (United States)

    Guo, Zhiqing; Döll, Katharina; Dastjerdi, Raana; Karlovsky, Petr; Dehne, Heinz-Wilhelm; Altincicek, Boran

    2014-01-01

    Species of Fusarium have significant agro-economical and human health-related impact by infecting diverse crop plants and synthesizing diverse mycotoxins. Here, we investigated interactions of grain-feeding Tenebrio molitor larvae with four grain-colonizing Fusarium species on wheat kernels. Since numerous metabolites produced by Fusarium spp. are toxic to insects, we tested the hypothesis that the insect senses and avoids Fusarium-colonized grains. We found that only kernels colonized with F. avenaceum or Beauveria bassiana (an insect-pathogenic fungal control) were avoided by the larvae as expected. Kernels colonized with F. proliferatum, F. poae or F. culmorum attracted T. molitor larvae significantly more than control kernels. The avoidance/preference correlated with larval feeding behaviors and weight gain. Interestingly, larvae that had consumed F. proliferatum- or F. poae-colonized kernels had similar survival rates as control. Larvae fed on F. culmorum-, F. avenaceum- or B. bassiana-colonized kernels had elevated mortality rates. HPLC analyses confirmed the following mycotoxins produced by the fungal strains on the kernels: fumonisins, enniatins and beauvericin by F. proliferatum, enniatins and beauvericin by F. poae, enniatins by F. avenaceum, and deoxynivalenol and zearalenone by F. culmorum. Our results indicate that T. molitor larvae have the ability to sense potential survival threats of kernels colonized with F. avenaceum or B. bassiana, but not with F. culmorum. Volatiles potentially along with gustatory cues produced by these fungi may represent survival threat signals for the larvae resulting in their avoidance. Although F. proliferatum or F. poae produced fumonisins, enniatins and beauvericin during kernel colonization, the larvae were able to use those kernels as diet without exhibiting increased mortality. Consumption of F. avenaceum-colonized kernels, however, increased larval mortality; these kernels had higher enniatin levels than F

  2. The effects of food level and conspecific density on biting and cannibalism in larval long-toed salamanders, Ambystoma macrodactylum.

    Science.gov (United States)

    Wildy, Erica L; Chivers, Douglas P; Kiesecker, Joseph M; Blaustein, Andrew R

    2001-07-01

    Previous studies have examined abiotic and biotic factors that facilitate agonistic behavior. For larval amphibians, food availability and conspecific density have been suggested as important factors influencing intraspecific aggression and cannibalism. In this study, we examined the separate and combined effects of food availability and density on the agonistic behavior and life history of larval long-toed salamanders, Ambystoma macrodactylum. We designed a 2×2 factorial experiment in which larvae were raised with either a high or low density of conspecifics and fed either a high or low level of food. For each treatment, we quantified the amount of group size variation, biting, and cannibalism occurring. Additionally, we examined survival to, time to and size at metamorphosis for all larvae. Results indicated that differences in both density and food level influenced all three life history traits measured. Moreover, differences in food level at which larvae were reared resulted in higher within-group size variation and heightened intraspecific biting while both density and food level contributed to increased cannibalism. We suggest that increased hunger levels and an uneven size structure promoted biting among larvae in the low food treatments. Moreover, these factors combined with a higher encounter rate with conspecifics in the high density treatments may have prompted larger individuals to seek an alternative food source in the form of smaller conspecifics.

  3. Uptake, absorption efficiency and elimination of DDT in marine phytoplankton, copepods and fish

    International Nuclear Information System (INIS)

    Wang Xinhong; Wang Wenxiong

    2005-01-01

    Uptake, absorption efficiency and elimination of DDT were measured in marine phytoplankton, copepods (Acartia erythraea) and fish (mangrove snappers Lutjanus argentimaculatus). The uptake rate constant of DDT from water decreased with increasing trophic level. The dietary absorption efficiency (AE) of DDT was 10-29% in copepods and 72-99% in fish. Food concentration did not significantly affect the AEs of DDT, but the AEs varied considerably among the different food diets. The elimination rate constants of DDT by the copepods were comparable following uptake from the diet and from the water. Elimination of DDT from the fish was exceedingly low. Both aqueous and dietary uptake are equally important for DDT accumulation in the copepods. In fish, dissolved exposure is a more significant route than intake from the diet. The predicted trophic transfer factors in the copepods and the fish are consistent with the field measurements in marine zooplankton and fish. -Biomagnification and exposure of DDT in a marine food chain is demonstrated by measurements of uptake and elimination rates and kinetic modeling

  4. Uptake of Cadmium, Lead and Arsenic by Tenebrio molitor and Hermetia illucens from Contaminated Substrates.

    Science.gov (United States)

    van der Fels-Klerx, H J; Camenzuli, L; van der Lee, M K; Oonincx, D G A B

    2016-01-01

    Insects have potential as a novel source of protein in feed and food production in Europe, provided they can be used safely. To date, limited information is available on the safety of insects, and toxic elements are one of the potential hazards of concern. Therefore, we aimed to investigate the potential accumulation of cadmium, lead and arsenic in larvae of two insect species, Tenebrio molitor (yellow mealworm) and Hermetia illucens (black soldier fly), which seem to hold potential as a source of food or feed. An experiment was designed with 14 treatments, each in triplicate, per insect species. Twelve treatments used feed that was spiked with cadmium, lead or arsenic at 0.5, 1 and 2 times the respective maximum allowable levels (ML) in complete feed, as established by the European Commission (EC). Two of the 14 treatments consisted of controls, using non-spiked feed. All insects per container (replicate) were harvested when the first larva in that container had completed its larval stage. Development time, survival rates and fresh weights were similar over all treatments, except for development time and total live weight of the half of the maximum limit treatment for cadmium of the black soldier fly. Bioaccumulation (bioaccumulation factor > 1) was seen in all treatments (including two controls) for lead and cadmium in black soldier fly larvae, and for the three arsenic treatments in the yellow mealworm larvae. In the three cadmium treatments, concentrations of cadmium in black soldier fly larvae are higher than the current EC maximum limit for feed materials. The same was seen for the 1.0 and 2.0 ML treatments of arsenic in the yellow mealworm larvae. From this study, it can be concluded that if insects are used as feed materials, the maximum limits of these elements in complete feed should be revised per insect species.

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Food pantry selection solutions: a randomized controlled trial in client-choice food pantries to nudge clients to targeted foods.

    Science.gov (United States)

    Wilson, Norbert L W; Just, David R; Swigert, Jeffery; Wansink, Brian

    2017-06-01

    Food pantries and food banks are interested in cost-effective methods to encourage the selection of targeted foods without restricting choices. Thus, this study evaluates the effectiveness of nudges toward targeted foods. In October/November 2014, we manipulated the display of a targeted product in a New York State food pantry. We evaluated the binary choice of the targeted good when we placed it in the front or the back of the category line (placement order) and when we presented the product in its original box or unboxed (packaging). The average uptake proportion for the back treatment was 0.231, 95% CI = 0.179, 0.29, n = 205, and for the front treatment, the proportion was 0.337, 95% CI = 0.272, 0.406, n = 238 with an odds ratio of 1.688, 95% CI = 1.088, 2.523. The average uptake for the unboxed treatment was 0.224, 95% CI = 0.174, 0.280, n = 255, and for the boxed intervention, the proportion was 0.356, 95% CI = 0.288, 0.429, n = 188 with an odds ratio of 1.923, 95% CI = 1.237, 2.991. Nudges increased uptake of the targeted food. The findings also hold when we control for a potential confounder. Low cost and unobtrusive nudges can be effective tools for food pantry organizers to encourage the selection of targeted foods. NCT02403882. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. An Exploration of Edible Palm Weevil Larvae (Akokono) as a Source of Nutrition and Livelihood: Perspectives From Ghanaian Stakeholders.

    Science.gov (United States)

    Laar, Amos; Kotoh, Agnes; Parker, Megan; Milani, Peiman; Tawiah, Charlotte; Soor, Shobhita; Anankware, Jacob P; Kalra, Nikhila; Manu, Grace; Tandoh, Akua; Zobrist, Stephanie; Engmann, Cyril; Pelto, Gretel

    2017-12-01

    Meeting the nutritive needs of infants and young children is a challenge in Ghana. Alternative animal source foods, including insects, could enhance infant and young child dietary quality while also improving livelihoods. To investigate the perspectives of Ghanaian stakeholders on the acceptability of the palm weevil larvae ( akokono) as a food source and the feasibility of micro-farming this local edible insect as a complementary food for infants and young children. We conducted an ethnographic study in the Brong-Ahafo Region of Ghana. First, 48 caregivers were asked questions about feeding and care practices, including attitudes toward production and consumption of akokono. Then, a selection of previously interviewed respondents joined 1 of 8 focus group discussions to provide further insight on key themes that emerged from earlier interviews. Concurrently, interviews with 25 other key local stakeholders were conducted. Respondents generally had favorable perceptions of akokono as a nutritious food. A small minority would not consume akokono for religious reasons. Key factors positively influencing the acceptability of akokono as a complementary food were familiarity with the consumption of akokono by the primary caregiver and health worker endorsement of akokono. Stakeholders consider the larvae farmable and were open to its domestication. Anticipated barriers to scaling up akokono micro-farming include a need for greater familiarity with and acceptance of the insect as food for infants and young children and creation of a sustainable market. Engagement with stakeholders, including health workers, will facilitate use of akokono as a complementary food.

  8. Perkembangan dan Kandungan Nutrisi Larva Hermetia illucens (Linnaeus (Diptera: Stratiomyidae pada Bungkil Kelapa Sawit

    Directory of Open Access Journals (Sweden)

    RACHMAWATI RACHMAWATI

    2015-09-01

    Full Text Available Hermetia illucens, is used as a reducing agent of palm kernel meal (PKM, as well as one of alternative protein sources for aquaculture purposes. Information about biology of H. illucens is absolutely required in mass production. The objectives of these researches were to study the development of H. illucens including the effect of supplementary food to the adult, and nutrient content of the immature stage. The sample of 20 larvae from each 3 replicates were measured and weighed on 0-19th day (larva and 24th day (pupa from egg hatching. H. illucens adults were fed by water and honey 5% (v/v. Eggs were collected and counted. Nutrient content of immature stage: 5, 10, 15, 20 days old (larvae, and 25 days old (prepupae reared on PKM were analyzed proximately. Dry matter was determined by weight loss on drying at 105 oC during overnight. Crude protein was determined by Kjeldahl procedure (N x 6.25, crude fat by soxhlet (ether extract, crude ash by determining the residue after heating at 550 oC for 4–5 h. Data were analyzed descriptively by average from triplicate. The development of H. illucens was shorter than those in previous studies as the differences of abiotical factor. PKM was a suitable medium for development. It was better, however, to fed the adult with honey since it could enhance the fecundity. The young larva certainly contained the best quality of nutrition. To meet the quantity of mass production, however, the use of the elder larva (bigger was suggested.

  9. The Galleria mellonella larvae as an in vivo model for evaluation of Shigella virulence.

    Science.gov (United States)

    Barnoy, Shoshana; Gancz, Hanan; Zhu, Yuewei; Honnold, Cary L; Zurawski, Daniel V; Venkatesan, Malabi M

    2017-07-04

    Shigella spp. causing bacterial diarrhea and dysentery are human enteroinvasive bacterial pathogens that are orally transmitted through contaminated food and water and cause bacillary dysentery. Although natural Shigella infections are restricted to humans and primates, several smaller animal models are used to analyze individual steps in pathogenesis. No animal model fully duplicates the human response and sustaining the models requires expensive animals, costly maintenance of animal facilities, veterinary services and approved animal protocols. This study proposes the development of the caterpillar larvae of Galleria mellonella as a simple, inexpensive, informative, and rapid in-vivo model for evaluating virulence and the interaction of Shigella with cells of the insect innate immunity. Virulent Shigella injected through the forelegs causes larvae death. The mortality rates were dependent on the Shigella strain, the infectious dose, and the presence of the virulence plasmid. Wild-type S. flexneri 2a, persisted and replicated within the larvae, resulting in haemocyte cell death, whereas plasmid-cured mutants were rapidly cleared. Histology of the infected larvae in conjunction with fluorescence, immunofluorescence, and transmission electron microscopy indicate that S. flexneri reside within a vacuole of the insect haemocytes that ultrastructurally resembles vacuoles described in studies with mouse and human macrophage cell lines. Some of these bacteria-laden vacuoles had double-membranes characteristic of autophagosomes. These results suggest that G. mellonella larvae can be used as an easy-to-use animal model to understand Shigella pathogenesis that requires none of the time and labor-consuming procedures typical of other systems.

  10. 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.

  11. The Impact of Variable Phytoplankton Stoichiometry on Projections of Primary Production, Food Quality, and Carbon Uptake in the Global Ocean

    Science.gov (United States)

    Kwiatkowski, Lester; Aumont, Olivier; Bopp, Laurent; Ciais, Philippe

    2018-04-01

    Ocean biogeochemical models are integral components of Earth system models used to project the evolution of the ocean carbon sink, as well as potential changes in the physical and chemical environment of marine ecosystems. In such models the stoichiometry of phytoplankton C:N:P is typically fixed at the Redfield ratio. The observed stoichiometry of phytoplankton, however, has been shown to considerably vary from Redfield values due to plasticity in the expression of phytoplankton cell structures with different elemental compositions. The intrinsic structure of fixed C:N:P models therefore has the potential to bias projections of the marine response to climate change. We assess the importance of variable stoichiometry on 21st century projections of net primary production, food quality, and ocean carbon uptake using the recently developed Pelagic Interactions Scheme for Carbon and Ecosystem Studies Quota (PISCES-QUOTA) ocean biogeochemistry model. The model simulates variable phytoplankton C:N:P stoichiometry and was run under historical and business-as-usual scenario forcing from 1850 to 2100. PISCES-QUOTA projects similar 21st century global net primary production decline (7.7%) to current generation fixed stoichiometry models. Global phytoplankton N and P content or food quality is projected to decline by 1.2% and 6.4% over the 21st century, respectively. The largest reductions in food quality are in the oligotrophic subtropical gyres and Arctic Ocean where declines by the end of the century can exceed 20%. Using the change in the carbon export efficiency in PISCES-QUOTA, we estimate that fixed stoichiometry models may be underestimating 21st century cumulative ocean carbon uptake by 0.5-3.5% (2.0-15.1 PgC).

  12. 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.

  13. Development of Lutzomyia intermedia and Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae larvae in different diets

    Directory of Open Access Journals (Sweden)

    WERMELINGER E. D.

    2001-01-01

    Full Text Available The objective of this research was to evaluate, in laboratory, the development of Lutzomyia intermedia and Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae larvae, vectors of leishmaniasis in Brazil, in the following diets: industrialized food for rabbits, dogs, hamsters and aquarium fishes, besides liver powder, cooked lettuce, wheat germ, beer yeast, oat, wheat bran and a diet denominated aged food. Except wheat bran for L. intermedia, all diets provided adequate development for both species, which showed that any of them can be used in laboratory insectaries for these insects. L. intermedia showed better development with most nutritious diets and both species presented better development with aged food. Fungi as an additional nutrient source for L. intermedia and L. longipalpis is suggested.

  14. The chemical form of plutonium in foodstuffs - its influence on gastro-intestinal uptake

    International Nuclear Information System (INIS)

    Cooper, J.R.

    1984-01-01

    A brief review is given of some studies of the chemical form of plutonium in food eaten by man and how this may influence gastrointestinal uptake. Phytate ligands, present in many foods, bind strongly to plutonium. High levels of enzyme phytase in rat intestines enhance the gastrointestinal uptake of plutonium phytate in rats compared to rabbits. Taking into account 1) the low levels of phytase in human intestine and 2) the possibility of competing precipitation reactions, it would seem unlikely that the phytate-mediated elevation of plutonium uptake seen in rats will apply to humans. (U.K.)

  15. 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.

  16. 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.

  17. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, Y.H.; Anjum, S.; Rahul x, Smita Jyoti

    2017-07-01

    Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05). The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05).

  18. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9

    International Nuclear Information System (INIS)

    Siddique, Y.H.; Anjum, S.; Rahul x, Smita Jyoti

    2017-01-01

    Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05). The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05).

  19. 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.

  20. Calcium transport into the cells of the sea urchin larva in relation to spicule formation.

    Science.gov (United States)

    Vidavsky, Netta; Addadi, Sefi; Schertel, Andreas; Ben-Ezra, David; Shpigel, Muki; Addadi, Lia; Weiner, Steve

    2016-10-24

    We investigated the manner in which the sea urchin larva takes up calcium from its body cavity into the primary mesenchymal cells (PMCs) that are responsible for spicule formation. We used the membrane-impermeable fluorescent dye calcein and alexa-dextran, with or without a calcium channel inhibitor, and imaged the larvae in vivo with selective-plane illumination microscopy. Both fluorescent molecules are taken up from the body cavity into the PMCs and ectoderm cells, where the two labels are predominantly colocalized in particles, whereas the calcium-binding calcein label is mainly excluded from the endoderm and is concentrated in the spicules. The presence of vesicles and vacuoles inside the PMCs that have openings through the plasma membrane directly to the body cavity was documented using high-resolution cryo-focused ion beam-SEM serial imaging. Some of the vesicles and vacuoles are interconnected to form large networks. We suggest that these vacuolar networks are involved in direct sea water uptake. We conclude that the calcium pathway from the body cavity into cells involves nonspecific endocytosis of sea water with its calcium.

  1. Characterization of a digestive α-amylase in the larvae of Pieris brassicae L. (Lepidoptera: Pieridae

    Directory of Open Access Journals (Sweden)

    Arash eZibaee

    2016-03-01

    Full Text Available The current study deals with a digestive α-amylase in the larvae of Pieris brassicae L. through purification, enzymatic characterization, gene expression and in vivo effect of a specific inhibitor, Acarbose. Although α-amylase activity was the highest in the whole gut homogenate of larvae but compartmentalization of amylolytic activity showed an equal activity in posterior midgut (PM and anterior midgut (AM. A three step purification using ammonium sulfate, Sepharyl G-100 and DEAE-Cellulose Fast flow revealed an enzyme with a specific activity of 5.18 U/mg, recovery of 13.20, purification fold of 19.25 and molecular weight of 88 kDa. The purified α-amylase had the highest activity at optimal pH and temperature of 8 and 35 ºC. Also, the enzyme had Vmax values of 4.64 and 3.02 U/mg protein and Km values of 1.37 and 1.74% using starch and glycogen as substrates, respectively. Different concentrations of acarbose, ethylenediamine tetraacetic acid and ethylene glycol-bis (β-aminoethylether N, N, N′, N′-tetraacetic acid significantly decreased activity of the purified α-amylase. The 4th instar larvae of P. brassicae were fed on the treated leaves of Raphanus sativus L. with 0.22 mM of Acarbose to find in vivo effects on nutritional indices, α-amylase activity and gene expression. The significant differences were only found in conversion efficiency of digested food, relative growth rate and metabolic cost of control and fed larvae on Acarbose. Also, amylolytic activity significantly decreased in the treated larvae by both biochemical and native-PAGE experiments. Results of RT-PCR revealed a gene with 621 bp length responsible for α-amylase expression that had 75% identity with Papilio xuthus and P. polytes. Finally, qRT-PCR revealed higher expression of α-amylase in control larvae compared to acarbose-fed ones.

  2. CONCEPT OF IN-OIL PROJECT BASED ON BIOCONVERSION OF BY-PRODUCTS FROM FOOD PROCESSING INDUSTRY

    Directory of Open Access Journals (Sweden)

    Wojciech Czekała

    2017-09-01

    The main assumption of the project is based on the introduction of by-products from the food processing industry to feeding with larvae of H. illucens. Biomass of insect larvae will then be processed into products that will be used for feed and energy purposes.

  3. The innate immune and systemic response in honey bees to a bacterial pathogen, Paenibacillus larvae

    Directory of Open Access Journals (Sweden)

    Foster Leonard J

    2009-08-01

    Full Text Available Abstract Background There is a major paradox in our understanding of honey bee immunity: the high population density in a bee colony implies a high rate of disease transmission among individuals, yet bees are predicted to express only two-thirds as many immunity genes as solitary insects, e.g., mosquito or fruit fly. This suggests that the immune response in bees is subdued in favor of social immunity, yet some specific immune factors are up-regulated in response to infection. To explore the response to infection more broadly, we employ mass spectrometry-based proteomics in a quantitative analysis of honey bee larvae infected with the bacterium Paenibacillus larvae. Newly-eclosed bee larvae, in the second stage of their life cycle, are susceptible to this infection, but become progressively more resistant with age. We used this host-pathogen system to probe not only the role of the immune system in responding to a highly evolved infection, but also what other mechanisms might be employed in response to infection. Results Using quantitative proteomics, we compared the hemolymph (insect blood of five-day old healthy and infected honey bee larvae and found a strong up-regulation of some metabolic enzymes and chaperones, while royal jelly (food and energy storage proteins were down-regulated. We also observed increased levels of the immune factors prophenoloxidase (proPO, lysozyme and the antimicrobial peptide hymenoptaecin. Furthermore, mass spectrometry evidence suggests that healthy larvae have significant levels of catalytically inactive proPO in the hemolymph that is proteolytically activated upon infection. Phenoloxidase (PO enzyme activity was undetectable in one or two-day-old larvae and increased dramatically thereafter, paralleling very closely the age-related ability of larvae to resist infection. Conclusion We propose a model for the host response to infection where energy stores and metabolic enzymes are regulated in concert with direct

  4. 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.

  5. 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.

  6. Arginine and proline applied as food additives stimulate high freeze tolerance in larvae of Drosophila melanogaster.

    Science.gov (United States)

    Koštál, Vladimír; Korbelová, Jaroslava; Poupardin, Rodolphe; Moos, Martin; Šimek, Petr

    2016-08-01

    The fruit fly Drosophila melanogaster is an insect of tropical origin. Its larval stage is evolutionarily adapted for rapid growth and development under warm conditions and shows high sensitivity to cold. In this study, we further developed an optimal acclimation and freezing protocol that significantly improves larval freeze tolerance (an ability to survive at -5°C when most of the freezable fraction of water is converted to ice). Using the optimal protocol, freeze survival to adult stage increased from 0.7% to 12.6% in the larvae fed standard diet (agar, sugar, yeast, cornmeal). Next, we fed the larvae diets augmented with 31 different amino compounds, administered in different concentrations, and observed their effects on larval metabolomic composition, viability, rate of development and freeze tolerance. While some diet additives were toxic, others showed positive effects on freeze tolerance. Statistical correlation revealed tight association between high freeze tolerance and high levels of amino compounds involved in arginine and proline metabolism. Proline- and arginine-augmented diets showed the highest potential, improving freeze survival to 42.1% and 50.6%, respectively. Two plausible mechanisms by which high concentrations of proline and arginine might stimulate high freeze tolerance are discussed: (i) proline, probably in combination with trehalose, could reduce partial unfolding of proteins and prevent membrane fusions in the larvae exposed to thermal stress (prior to freezing) or during freeze dehydration; (ii) both arginine and proline are exceptional among amino compounds in their ability to form supramolecular aggregates which probably bind partially unfolded proteins and inhibit their aggregation under increasing freeze dehydration. © 2016. Published by The Company of Biologists Ltd.

  7. An investigation of radionuclide uptake into food crops grown in soils treated with bauxite mining residues

    International Nuclear Information System (INIS)

    Cooper, M.B.; Clarke, P.C.; Robertson, W.; McPharlin, I.R.; Jeffrey, R.C.

    1994-01-01

    Sandy soils of the coastal plain area of Western Australia have poor phosphorous retention capacity which leads to pollution of surface water bodies in the region. Application of bauxite mining residues (termed 'red mud') to vegetable and crops has been proposed as a solution to increase the phosphorous and water retention and thereby reduce the leaching of nutrients. The thorium and radium-226 concentrations in the 'red mud' residues are in excess of 1 kBq/kg, and 300 Bq/kg respectively. Potentially, the use of these residues on agricultural land could result in increased levels of radionuclides in food grown in amended soils. The transfer of long-lived radionuclides of both the natural thorium and uranium series to a variety of vegetable crops grown under controlled conditions is investigated. The effects of varying the rates of application of 'red mud' and phosphate fertilizers on radionuclide uptake are studied. It has been shown previously that fallout caesium-137 is sandy soils of the region transfers readily to food and grazing crops. Some of the parameters which influence that transfer are also examined. (author). 14 refs., 1 fig., 8 tabs

  8. 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

  9. Mechanisms of60Co uptake and loss by Scenedesmus obliquus and transfer to two benthic organisms

    International Nuclear Information System (INIS)

    Nucho, R.

    1989-10-01

    The affinity of Scenedesmus obliquus for 60 Co has been confirmed under various experimental conditions allowing for the age of cultures, the physiological state of the cells, the radioactivity level and stable cobalt concentration in the medium, and the acute or periodic nature of the contamination. The dry weight 60 Co concentration factor may reach 4x10 4 in LCO culture medium and is about 10 4 in natural water. 60 Co uptake by algae is a 95% passive phenomenon, initiated by radionuclide absorption on the cell walls and followed by intracellular diffusion in accordance with Fick's law. From the initial cationic form, radiocobalt develops anion forms at a rate proportional to the algal biomass, resulting in lower contamination of old and dense cultures. After transfer in natural or artificial nonradioctive medium, 60 Co is eliminated by Scenedesmus obliquus, mainly as Co 2+ ions, according to a two-phase exponential process with two biological half-lives. The study of radioactive cobalt transfer from algae to gammarids and to midge larvae reveals the extend to which phytoplankton predominate over water and sediment in contaminating these two organisms. The total 60 Co uptake depends significantly on whether the cells are incorporated in or deposited on the sediment. No biomagnification phenomenon of the radionuclide was found in any case, as the transfer factor was less than 1. Depuration of 60 Co by organisms involved a two-phase exponential process regardless of whether uptake occured directly or from food. The presence of sediment appears to reduce the 60 Co desorption rate, but from 85 to 95% of the initial quantity is eliminated. This percentage does not depend on the transfer pathway or the presence of organic matter, and indicates very slight assimilation of radiocobalt ingested with algal cells [fr

  10. 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.

  11. Tritium uptake kinetics in crayfish (Orconectes immunis)

    International Nuclear Information System (INIS)

    Patrick, P.H.

    1985-06-01

    Uptake of tritiated water (HTO) by Orconectes immunis was investigated under laboratory conditions. Tritium uptake in the tissue-free water fraction (TFWT) was described using an exponential model. When steady-state was reached, the ratio of TFWT to HTO was approximately 0.9. Uptake of tritium in the organically-bound fraction (OBT) proceeded slowly, and had not reached steady-state after 117 days of culture. Although steady-state was never reached, the maximum observed ration of OBT to TFWT in whole animals was approximately 0.6. However, this ratio exceeded unity in the exoskeleton. Specific activity ratios of OBT between crayfish and lettuce (food source) were less than or at unity for various test conditions

  12. Substituição de alimento vivo por alimento inerte na larvicultura intensiva do tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus = Replacement of live food for inert food on larviculture of tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus

    Directory of Open Access Journals (Sweden)

    Danieli Cuzini Lombardi

    2008-10-01

    Full Text Available Com este trabalho objetivou-se avaliar a substituição de náuplios de Artemia salina por alimentos inertes durante a larvicultura do tambacu. Na primeira fase, com duração de 12 dias, as larvas foram alimentadas com: náuplio de Artemia salina, cyclop-eeze e ovo de Artemia salina. Na segunda fase, com duração de dez dias, foram utilizadas larvas alimentadas com náuplios de Artemia salina provenientes da primeira fase e testados os mesmos três alimentos. A qualidade da água manteve-se em condições adequadas para alarvicultura nas duas fases. As larvas da primeira fase alimentadas com náuplios de Artemia salina obtiveram os melhores resultados em crescimento, sobrevivência e desempenho produtivo. Na segunda fase, o crescimento, a sobrevivência e o desempenho produtivo das larvas alimentadas com náuplios de Artemia salina e ovo de Artemia salina foram semelhantes. Nas duas fases, o custo com alimento foi mais baixo nas larvas alimentadas com náuplios de Artemia salina. Os resultados obtidos mostram que nas duas fases de larvicultura testadas a oferta de náuplios de Artemia salina é a melhor estratégia alimentar por proporcionar boa sobrevivência, crescimento e bom desempenho produtivo, além de menor custo.The aim of this work was to evaluate the replacement of Artemia salina nauplii by inert food during larviculture of tambacu. On the first phase with duration of 12 days, the larvae were fed with one of the following foods: Artemia salina nauplii, cyclop-eeze or Artemia salina egg. On the second phase, with 10 days of duration, larvae fed with Artemia salina nauplii were utilized in the first experiment and the same food treatments were tested. Water quality was adequate forlarvae rearing in both phases. The larvae from the first phase that fed with Artemia salina nauplii presented better growth, survival rate and yield. On the second phase, the growth, survival and yield of larvae fed with Artemia salina nauplii and eggs were

  13. A model for the interaction between gadoid larvae and their nauplii prey.

    Science.gov (United States)

    Johansen, Rune

    2007-07-01

    A continuous model for the growth and death of gadoid larvae, including ecological interactions with their nauplii prey, is examined. The present model has a simpler structure than the model due to Cushing and Horwood [D.H. Cushing, J.W. Horwood, The growth and death of fish larvae. J. Plankt. Res. 16 (3) (1994) 291-300] as it does not explicitly incorporate larval metabolism, although indirectly metabolism is included by means of equations for larval growth. Despite this, the model yields related, although not entirely equivalent, results to those obtained by Cushing and Horwood. In the present model, overcompensation (cf. [W.E. Ricker, Stock and Recruitment, J. Fish. Res. Board. Can. 11 (1954) 559-623]) occurs at limited initial food levels, while at infinite food levels, the recruitment curve becomes monotonically increasing towards an upper limit (cf. [R.J.H. Beverton, S.J. Holt, On the dynamics of exploited fish populations. Fish. Invest. Lond. I 19 (1957)]). Moreover, the present study suggests that the duration of the larval stage, the metamorphosis time tau is highly important to the recruitment process, in accordance with Cushing and Horwood. When food is limited the metamorphosis is delayed, causing the larval population to experience (density dependent) mortality for a sufficient long time to make the recruitment curve overcompensatory. It is not necessarily the desire to derive a particular formula for the recruitment curve, as this is probably impossible anyway, except for particular examples. However, reduced versions of the model that in some sense are close to the original model, are examined, and it is argued that many general features of the general model are retained in such examples.

  14. Food and feeding performance of Pellonula leonensis (Reajon ...

    African Journals Online (AJOL)

    Food and feeding performance of Pellonula leonensis (Reajon, 1917) ... fed more on ants and fish larvae while juveniles fed more on detritus, crustaceans and sand. ... Pellonula was considered piscivorous and cannibalistic its feeding habit.

  15. Ex situ protection of the European mudminnow (Umbra krameri Walbaum, 1792: Spawning substrate preference for larvae rearing under controlled conditions

    Directory of Open Access Journals (Sweden)

    Kucska Balázs

    2016-01-01

    Full Text Available Captive breeding programs of endangered fish species, such as the European mudminnow Umbra krameri, are essential for population restoration. To improve captive spawning and larvae rearing under controlled conditions, two experiments were carried out. In the first, the spawning substrate preference was tested in triplicate, where five different types of artificial surface were provided for mudminnow pairs:(isand, (iiartificial plants, (iiigravel, (ivsand + artificial plants and(vgravel + artificial plants. All fish preferred the gravel + artificial plant combination, which indicates that this type of surface could be the most appropriate for spawning in captivity. In the second trial, three feeding protocols were tested in triplicate under controlled conditions. In the first treatment fish were fed exclusively with Artemia nauplii; in the second treatment fish were fed with Artemiafor the first ten days then Artemia was gradually replaced with dry feed; for the third group the transition period started after 5 days of Artemia feeding. Although the survival rate of larvae could be maintained at a high level in some of the feeding protocols, a strong decrease in the growth rate was obvious in all diets containing dry food, which means that live food is essential for the first three weeks of mudminnow larvae rearing.

  16. Study on Fungal Flora in the Midgut of the Larva and Adult of the Different Populations of the Malaria Vector Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    L Tajedin

    2009-07-01

    Full Text Available Abstract Background: Many microorganisms in midgut of mosquito challenge with their host and also other pathogens pre­sent in midgut. The aim of this study was presence of non-pathogens microorganisms like fungal flora which may be cru­cial on interaction between vectors and pathogens."nMethods: Different populations of Anopheles stephensi were reared in insectary and objected to determine fungal flora in their midguts. The midgut paunch of mosquito adults and larvae as well as breading water and larval food sam­ples transferred on Subaru-dextrose agar, in order to detect the environment fungus."nResults: Although four fungi, Aspergillus, Rhizopus, Geotrichum and Sacharomyces were found in the food and wa­ter, but only Aspiragilus observed in the midgut of larvae. No fungus was found in the midgut of adults. This is the first report on fungal flora in the midgut of the adults and larvae of An. stephensi and possible stadial transmission of fungi from immature stages to adults."nConclusion: The midgut environment of adults is not compatible for survivorship of fungi but the larval midgut may con­tain few fungi as a host or even pathogen.

  17. Evaluation of released malathion and spinosad from chitosan/alginate/gelatin capsules against Culex pipiens larvae

    Directory of Open Access Journals (Sweden)

    Badawy MEI

    2016-09-01

    Full Text Available Mohamed EI Badawy,1 Nehad EM Taktak,2 Osama M Awad,2 Souraya A Elfiki,2 Nadia E Abou El-Ela2 1Department of Pesticide Chemistry and Technology, Faculty of Agriculture, 2Department of Tropical Health, High Institute of Public Health, Alexandria University, Alexandria, Egypt Abstract: Efficacy of spinosad and malathion loaded in eco-friendly biodegradable formulations was evaluated for controlling Culex pipiens larvae. Malathion (organophosphorus larvicide and spinosad (naturally derived insecticide were loaded on chitosan/alginate/gelatin capsules. Capsules were characterized by size measurement, scanning electron microscopy, Fourier transform infrared spectroscopy, and water uptake. In vitro release kinetics of the larvicides was studied in the running and stagnant water. Biochemical studies on the larvae treated with technical and formulated insecticides were also demonstrated. The results indicated that the released spinosad was active for a long time up to 48 and 211 days in the running and stagnant water, respectively. However, the capsules loaded with malathion showed larvicidal activity for 20 and 27 days in the running and stagnant water, respectively. Technical and formulated malathion and spinosad had an inhibition effect on acetylcholinesterase, carboxylesterase, and glutathione S-transferase. The results proved that the prepared capsules consisting of biodegradable polymers containing larvicides could be effective as controlled-release formulation against C. pipiens larvae for a long period. Keywords: chitosan capsules, larvicide, controlled-release formulation, swelling, mosquitocidal activity, Culex pipiens, biochemical study

  18. Evaluation of the toxic potential of aspartame in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ Bg9

    Directory of Open Access Journals (Sweden)

    YASIR HASAN SIDDIQUE

    2017-07-01

    Full Text Available Aspartame is commonly used as a sweetener in prepared foods, beverages and in recipes. In the present study the possible toxic effects of aspartame were studied in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ Bg9. The third instar larvae were allowed to feed on the diet having different doses of aspartame. The results obtained in the present study suggest that the exposure of third instar larvae to the diet having 20, 40, 80, 160 and 320 mM of aspartame did not show any significant the toxic effects after 24 hours of the exposure compared to control (p<0.05. The results for pupae formation and emergence of flies also did not show any significant difference compared to control (p<0.05.

  19. PENGARUH WAKTU PERPINDAHAN PAKAN ALAMI KE PAKAN BUATAN BERENZIM TERHADAP SINTASAN, PERTUMBUHAN PADA PEMELIHARAAN LARVA IKAN BAUNG (Mystus nemurus cv

    Directory of Open Access Journals (Sweden)

    Siti Aysah

    2016-06-01

    Full Text Available This study aimed to determine the switching time from natural food to artificial food with the addition of mix enzyme in baung larval rearing. The results showed that the survival rate of baung larvae had the highest  score in treatment E (natural feed Artemia salina aged 3 days to 7 days followed by artificial feed in the form of pasta until age 30 days, did not differ with treatment A. Treatment A (Natural Food Artemia salina was given at the age of 3 days to 8 days and then followed by artificial food (shrimp flour + mix enzyme from the age of 9 days to 15 days  artificial feeding was continued until the age of 30 days showed the highest absolute growth was 0.62 grams and the value of relative growth rate of 14.25 grams did not differ  with B, C and E treatments. The highest Individual weight, protein content and  mix enzyme activity on all measurement  of baung larvae found in treatment A.  Water quality of maintenance media of eel was the temperature 27,33oC, pH 7,86, dissolve oxygen  4,76 mg/l and ammonia 0,93 mg/l.

  20. 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.

  1. Seletividade alimentar de organismos-alimento por formas jovens de pacu Piaractus mesopotamicus (Holmberg, 1887 e curimba Prochilodus lineatus (Valenciennes, 1836 - DOI: 10.4025/actascibiolsci.v29i2.523 Selective feeding of food organisms by fish larvae of Piaractus mesopotamicus (Holmberg, 1887 and Prochilodus lineatus (Valenciennes, 1836 - DOI: 10.4025/actascibiolsci.v29i2.523

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Bento Fernandes

    2007-12-01

    Full Text Available Objetivou-se avaliar a seleção alimentar de organismos-alimento por formas jovens de pacu (Piaractus mesopotamicus e curimba (Prochilodus lineatus com diferentes idades (6, 12, 19 e 26 dias, na presença e ausência de Pistia stratiotes. Foram utilizados quatro tratamentos (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba e quatro repetições. A cada sete dias, foram coletadas 24 larvas de cada espécie de peixe dos tanques, sendo estas mantidas em jejum por 24 horas. Depois de distribuídas nos aquários com plâncton, as larvas permaneceram por três horas, sendo coletadas e fixadas para análise, juntamente com as amostras de água. Os tratos digestórios das larvas foram retirados e analisados sob microscópio óptico. Observaram-se diferenças estatísticas na seletividade alimentar de organismos planctônicos por larvas de mesma espécie, em diferentes idades e também entre larvas de espécies diferentes, com mesma idade, não diferindo quanto à presença ou ausência de P. stratiotes. As formas jovens de pacu e curimba selecionaram organismos similares aos seis dias de idade, passando por alterações até o 26º dia. À medida que se desenvolveram, as larvas de pacu passaram a selecionar cladóceros e ostrácodos e as de curimba, protozoários e algas.The objective was to evaluate the feeding selection of food organisms for two species of fish larvae (pacu and curimba at different ages (6, 12, 19 and 26 days after eclosion, in the presence or absence of Pistia stratiotes. Four treatments were used (T1 = pacu + P. stratiotes; T2 = pacu; T3 = curimba + P. stratiotes; T4 = curimba and four replications. Every seven days, 24 fish larvae of each species were collected, and kept without food for 24 hours. After being distributed in the aquariums with plankton, the larvae stayed for three hours, and were collected and prepared for analysis, along with the water samples. The digestive tract of the fish larvae

  2. On the edge of death: Rates of decline and lower thresholds of biochemical condition in food-deprived fish larvae and juveniles

    DEFF Research Database (Denmark)

    Meyer, Stefan; Caldarone, E.M.; Chicharo, M.A.

    2012-01-01

    Gaining reliable estimates of how long fish early life stages can survive without feeding and how starvation rate and time until death are influenced by body size, temperature and species is critical to understanding processes controlling mortality in the sea. The present study is an across-speci...... are viable proxies for the physiological processes under food deprivation of individual fish pre-recruits in the laboratory and provide useful metrics for research on the role of starvation in the sea......Gaining reliable estimates of how long fish early life stages can survive without feeding and how starvation rate and time until death are influenced by body size, temperature and species is critical to understanding processes controlling mortality in the sea. The present study is an across......-species analysis of starvation-induced changes in biochemical condition in early life stages of ninemarine and freshwater fishes. Datawere compiled on changes in body size (dry weight, DW) and biochemical condition (standardized RNA–DNA ratio, sRD) throughout the course of starvation of yolk-sac and feeding larvae...

  3. Dual impact of temperature on growth and mortality of marine fish larvae in a shallow estuarine habitat

    Science.gov (United States)

    Arula, Timo; Laur, Kerli; Simm, Mart; Ojaveer, Henn

    2015-12-01

    High individual growth and mortality rates of herring Clupea harengus membras and goby Pomatoschistus spp. larvae were observed in the estuarine habitat of the Gulf of Riga, Baltic Sea. Both instantaneous mortality (0.76-1.05) as well as growth rate (0.41-0.82 mm day-1) of larval herring were amongst highest observed elsewhere previously. Mortality rates of goby larvae were also high (0.57-1.05), while first ever data on growth rates were provided in this study (0.23-0.35 mm day-1). Our study also evidenced that higher growth rate of marine fish larvae did not result in lower mortalities. We suggest that high growth and mortality rates primarily resulted from a rapidly increasing and high (>18 °C) water temperature that masked potential food-web effects. The explanation for observed patterns lies in the interactive manner temperature contributed: i) facilitating prey production, which supported high growth rate and decreased mortalities; ii) exceeding physiological thermal optimum of larvae, which resulted in decreased growth rate and generally high mortalities. Our investigation suggests that the projected climate warming may have significant effect on early life history stages of the dominating marine fish species inhabiting shallow estuaries.

  4. Food preservation technologies developed at BARC

    International Nuclear Information System (INIS)

    Jain, M.P.

    2013-01-01

    Food irradiation is important as it is being used to disinfest food grains, pulses, wheat flour, rice, semolina, raisins etc; quarantining and shelf life increasing of fruits like mangoes; microbial decontamination of spices; sprout inhibition of tubers and bulbs; shelf life increasing and pathogen control of meat and fish. Category-IV type irradiators based on gamma rays exposure of food are currently being employed for this purpose. Cobalt-60 isotope is produced in the nuclear reactors. Isotope gives gamma rays as its nucleus is unstable. The gamma rays pass through the food items and inhibit sprouting of tubers and bulbs, kill bacteria, virus and the larvae of insects

  5. 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.

  6. 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.)

  7. Characterization of antennal sensilla, larvae morphology and olfactory genes of Melipona scutellaris stingless bee.

    Science.gov (United States)

    Carvalho, Washington João de; Fujimura, Patrícia Tieme; Bonetti, Ana Maria; Goulart, Luiz Ricardo; Cloonan, Kevin; da Silva, Neide Maria; Araújo, Ester Cristina Borges; Ueira-Vieira, Carlos; Leal, Walter S

    2017-01-01

    There is growing evidence in the literature suggesting that caste differentiation in the stingless bee, Melipona scutellaris, and other bees in the genus Melipona, is triggered by environmental signals, particularly a primer pheromone. With the proper amount of food and a chemical stimulus, 25% of females emerge as queens, in agreement with a long-standing "two loci/two alleles model" proposed in the 1950s. We surmised that these larvae must be equipped with an olfactory system for reception of these chemical signals. Here we describe for the first time the diversity of antennal sensilla in adults and the morphology of larvae of M. scutellaris. Having found evidence for putative olfactory sensilla in larvae, we next asked whether olfactory proteins were expressed in larvae. Since the molecular basis of M. scutellaris is still unknown, we cloned olfactory genes encoding chemosensory proteins (CSP) and odorant-binding proteins (OBPs) using M. scutellaris cDNA template and primers designed on the basis CSPs and OBPs previously reported from the European honeybee, Apis mellifera. We cloned two CSP and two OBP genes and then attempted to express the proteins encoded by these genes. With a recombinant OBP, MscuOBP8, and a combinatorial single-chain variable fragment antibody library, we generated anti-MscuOBP8 monoclonal antibody. By immunohistochemistry we demonstrated that the anti-MscuOBP8 binds specifically to the MscuOBP8. Next, we found evidence that MscuOBP8 is expressed in M. scutellaris larvae and it is located in the mandibular region, thus further supporting the hypothesis of olfactory function in immature stages. Lastly, molecular modeling suggests that MscuOBP8 may function as a carrier of primer pheromones or other ligands.

  8. Characterization of antennal sensilla, larvae morphology and olfactory genes of Melipona scutellaris stingless bee.

    Directory of Open Access Journals (Sweden)

    Washington João de Carvalho

    Full Text Available There is growing evidence in the literature suggesting that caste differentiation in the stingless bee, Melipona scutellaris, and other bees in the genus Melipona, is triggered by environmental signals, particularly a primer pheromone. With the proper amount of food and a chemical stimulus, 25% of females emerge as queens, in agreement with a long-standing "two loci/two alleles model" proposed in the 1950s. We surmised that these larvae must be equipped with an olfactory system for reception of these chemical signals. Here we describe for the first time the diversity of antennal sensilla in adults and the morphology of larvae of M. scutellaris. Having found evidence for putative olfactory sensilla in larvae, we next asked whether olfactory proteins were expressed in larvae. Since the molecular basis of M. scutellaris is still unknown, we cloned olfactory genes encoding chemosensory proteins (CSP and odorant-binding proteins (OBPs using M. scutellaris cDNA template and primers designed on the basis CSPs and OBPs previously reported from the European honeybee, Apis mellifera. We cloned two CSP and two OBP genes and then attempted to express the proteins encoded by these genes. With a recombinant OBP, MscuOBP8, and a combinatorial single-chain variable fragment antibody library, we generated anti-MscuOBP8 monoclonal antibody. By immunohistochemistry we demonstrated that the anti-MscuOBP8 binds specifically to the MscuOBP8. Next, we found evidence that MscuOBP8 is expressed in M. scutellaris larvae and it is located in the mandibular region, thus further supporting the hypothesis of olfactory function in immature stages. Lastly, molecular modeling suggests that MscuOBP8 may function as a carrier of primer pheromones or other ligands.

  9. 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.

  10. Defensive repertoire of Drosophila larvae in response to toxic fungi.

    Science.gov (United States)

    Trienens, Monika; Kraaijeveld, Ken; Wertheim, Bregje

    2017-10-01

    Chemical warfare including insecticidal secondary metabolites is a well-known strategy for environmental microbes to monopolize a food source. Insects in turn have evolved behavioural and physiological defences to eradicate or neutralize the harmful microorganisms. We studied the defensive repertoire of insects in this interference competition by combining behavioural and developmental assays with whole-transcriptome time-series analysis. Confrontation with the toxic filamentous fungus Aspergillus nidulans severely reduced the survival of Drosophila melanogaster larvae. Nonetheless, the larvae did not behaviourally avoid the fungus, but aggregated at it. Confrontation with fungi strongly affected larval gene expression, including many genes involved in detoxification (e.g., CYP, GST and UGT genes) and the formation of the insect cuticle (e.g., Tweedle genes). The most strongly upregulated genes were several members of the insect-specific gene family Osiris, and CHK-kinase-like domains were over-represented. Immune responses were not activated, reflecting the competitive rather than pathogenic nature of the antagonistic interaction. While internal microbes are widely acknowledged as important, our study emphasizes the underappreciated role of environmental microbes as fierce competitors. © 2017 John Wiley & Sons Ltd.

  11. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm).

    Science.gov (United States)

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju; Moon, Kyoung-Sik

    2014-06-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions.

  12. Characterization of zebrafish larvae suction feeding flow using μPIV and optical coherence tomography

    OpenAIRE

    Pekkan, Kerem; Uslu, Fazıl E.; Chang, Brain; Mani, Karthick; Chen, Chia-Yuan; Holzman, Roi

    2016-01-01

    The hydrodynamics of suction feeding is critical for the survival of fish larvae; failure to capture food during the onset of autonomous feeding can rapidly lead to starvation and mortality. Fluid mechanics experiments that investigate the suction feeding of suspended particles are limited to adult fishes, which operate at large Reynolds numbers. This manuscript presents the first literature results in which the external velocity fields generated during suction feeding of early zebrafish larv...

  13. 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

  14. Antioxidant enzyme level response to prooxidant allelochemicals in larvae of the southern armyworm moth, Spodoptera eridania.

    Science.gov (United States)

    Pritsos, C A; Ahmad, S; Elliott, A J; Pardini, R S

    1990-01-01

    Larvae of the southern armyworm, Spodoptera eridania, are highly polyphagous feeders which frequently encounter and feed upon plants containing high levels of prooxidant allelochemicals. While ingestion of moderate quantities of prooxidants can be tolerated by these larvae, ingestion of larger quantities can result in toxicity. Studies were conducted to assess the role of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in the protection of S. eridania against redox active prooxidant plant allelochemicals. Dietary exposure of mid-fifth-instar larvae to either quercetin (a flavonoid) or xanthotoxin (a photoactive furanocoumarin), which generate superoxide radical, and singlet oxygen, respectively, resulted in an increase in SOD levels. CAT levels increased in all groups of S. eridania including control insects. This may have been due to the sudden exposure to food following an extended fast of 18 h (to insure that larvae would not reject the diet because of the prooxidants' bitter taste) with an eventual lowering of CAT values with time. GR activities did not significantly change except for a slight inhibition at the highest prooxidant concentrations used at 12-h post-ingestion. The data from these studies suggest that SOD responds to prooxidant challenges in these insects and together with CAT and GR contributes to the insect's defense against potentially toxic prooxidant compounds.

  15. Assessment of Listeria monocytogenes virulence in the Galleria mellonella insect larvae model.

    Directory of Open Access Journals (Sweden)

    Mira Rakic Martinez

    Full Text Available Several animal models have been used to understand the molecular basis of the pathogenicity, infectious dose and strain to strain variation of Listeria monocytogenes. The greater wax worm Galleria mellonella, as an alternative model, provides some useful advantages not available with other models and has already been described as suitable for the virulence assessment of various pathogens including L. monocytogenes. The objectives of this study are: 1 confirming the usefulness of this model with a wide panel of Listeria spp. including non-pathogenic L. innocua, L. seeligeri, L. welshimeri and animal pathogen L. ivanovii; 2 assessment of virulence of several isogenic in-frame deletion mutants in virulence and stress related genes of L. monocytogenes and 3 virulence assessment of paired food and clinical isolates of L. monocytogenes from 14 major listeriosis outbreaks occurred worldwide between 1980 and 2015. Larvae injected with different concentrations of Listeria were incubated at 37°C and monitored over seven days for time needed to kill 50% of larvae (LT50 and to determine change of bacterial population in G. mellonella, 2 and 24 hours post-inoculation. Non-pathogenic members of Listeria and L. ivanovii showed significantly (P < 0.05 higher LT50 (lower virulence than the wild type L. monocytogenes strains. Isogenic mutants of L. monocytogenes with the deletions in prfA, plcA, hly, actA and virR genes, also showed significantly (P < 0.05 higher LT50 than the wild type strain at the inoculum of 106CFU/larva. Food isolates had significantly (P < 0.05 lower virulence than the paired clinical isolates, at all three inoculum concentrations. L. monocytogenes strains related to non-invasive (gastroenteritis outbreaks of listeriosis showed significantly (P < 0.05 lower virulence than isolates of the same serotype obtained from outbreaks with invasive symptoms. The difference, however, was dose and strain- dependent. No significant differences in

  16. 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.

  17. 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.

  18. 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.

  19. Dioxin and phthalate uptake and assimilation by the green mussel Perna viridis

    International Nuclear Information System (INIS)

    Wang, Wen-Xiong; Zhang, Qiong

    2013-01-01

    In this study, the aqueous uptake and dietary assimilation (trophic transfer) of two endocrine disrupting compounds (dioxin and phathalic acid) in the green mussel Perna viridis were quantified. During short-term exposure period, dioxin rapidly sorbed onto phytoplankton and its accumulation was much higher than that of phthalate. The uptake of these two compounds by the mussels increased with increasing temperature and salinity (for dioxin only). The dietary assimilation of the two contaminants was rather modest (10–64% for dioxin and 20–47% for phthalate), and was greatly dependent on the food species and concentration. Interestingly, dietary assimilation increased with increasing diatom food concentration. Gut passage time was partially responsible for the variable dietary assimilation. Given the high dissolved uptake rate and the modest dietary assimilation, aqueous exposure was predicted to be the dominant bioaccumulation source for both dioxin and phthalate in the green mussels under most conditions. -- Capsule: Aqueous uptake was the predominant pathway for dioxin and phthalate accumulation in marine green mussels

  20. A fly in the ointment: evaluation of traditional use of plants to repel and kill blowfly larvae in fermented fish.

    Directory of Open Access Journals (Sweden)

    Hugo J de Boer

    Full Text Available INTRODUCTION: In rural areas in Laos, fly larvae infestations are common in fermenting fish. Blowflies (Chrysomya megacephala, Diptera: Calliphoridae are attracted to oviposit (and/or larviposit onto fermenting fish which results in infestations with fly larvae. Knowledge of traditional use of plants to repel larvae during the production of fermented fish is common and widespread in Lao PDR. RESEARCH QUESTIONS: How effective are the most salient species in repelling, and killing fly larvae in fermenting fish? MATERIAL AND METHODS: The three plant species most frequently reported to repel fly larvae during an ethnobotanical survey throughout Lao PDR were tested for repellence and larvicidal activity of fly larvae infesting fermented fish. The lethality and repellence of Tadehagi triquetrum (L. H. Ohashi (Fabaceae, Uraria crinita (L. Desv. ex DC. (Fabaceae and Bambusa multiplex (Lour. Raeusch. ex Schult. & Schult. f. (Poaceae were tested in an experimental design using fermenting fish in Vientiane, Lao PDR. RESULTS: The repellent effect of fresh material of T. triquetrum and U. crinita, and the larvicidal effect of fresh B. multiplex, is significantly more effective than that of dried material of the same species, and the total effect (repellence and larvicidal effect combined for each of the three species was significantly more effective for fresh than for dry material. Fresh material of T. triquetrum, U. crinita, or B. multiplex added on top of the fermenting fish repelled 50%, 54%, 37%, and killed 22%, 28%, and 40% of fly larvae. The total effect was not significantly different per species at 72%, 82%, and 77%, respectively. DISCUSSION AND CONCLUSIONS: The three most salient species are effective in repelling and killing fly larvae in the production of fermented fish, and may be essential to augment food safety during traditional fermentation in open jars.

  1. 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

  2. Comparison of genetic and visual identification of cisco and lake whitefish larvae from Chaumont Bay, Lake Ontario

    Science.gov (United States)

    George, Ellen M.; Hare, Matthew P.; Crabtree, Darran L.; Lantry, Brian F.; Rudstam, Lars G.

    2017-01-01

    Cisco Coregonus artedi are an important component of native food webs in the Great Lakes, and their restoration is instrumental to the recovery of lake trout Salvelinus namaycush and Atlantic salmon Salmo salar. Difficulties with visual identification of larvae can confound early life history surveys, as cisco are often difficult to distinguish from lake whitefish C. clupeaformis. We compared traditional visual species identification methods to genetic identifications based on barcoding of the mitochondrial cytochrome C oxidase I gene for 726 coregonine larvae caught in Chaumont Bay, Lake Ontario. We found little agreement between the visual characteristics of cisco identified by genetic barcoding and the most widely used dichotomous key, and the considerable overlap in ranges of traditionally utilized metrics suggest that visual identification of coregonine larvae from Chaumont Bay is impractical. Coregonines are highly variable and plastic species, and often display wide variations in morphometric characteristics across their broad range. This study highlights the importance of developing accurate, geographically appropriate larval identification methods in order to best inform cisco restoration and management efforts.

  3. Models of prey capture in larval fish

    NARCIS (Netherlands)

    Drost, M.R.

    1986-01-01

    The food uptake of larval carp and pike is described from high speed movies with synchronous lateral and ventral views.

    During prey intake by larval fishes the velocities of the created suction flow are high relative to their own size: 0.3 m/s for carp larvae of 6

  4. Producción artesanal del rotífero Philodina sp. y de algas para la alimentación de post-larvas de bocachico Artisan production of rotifero and algaes for bocachico post-larva feeding

    Directory of Open Access Journals (Sweden)

    Victoria Eugenia Quintero P

    2009-01-01

    Full Text Available El cultivo de algas mixtas se realizó en el Instituto de Piscicultura Tropical de la Corporación Autónoma Regional del Valle del Cauca (Buga 25 ºC y 969 m.s.n.m. utilizando fertilizantes inorgánicos en baldes plásticos, se produjeron en promedio 386 x 10³ células/ml de cultivo. En el cultivo de Philodina en frascos de vidrio alimentado con algas y levadura, se obtuvieron 410 rotíferos/ml de cultivo. Se evaluaron tres tratamientos: rotíferos enriquecidos con aceite de pescado; rotíferos más algas (Chlorella, Scenedesmus, Pediastrum, Spyrogira y Anabaena y Artemia salina + Spirulina, usando 100 post-larvas de bocachico/acuario, alimentadas dos veces al día según biomasa sembrada. El mayor porcentaje de sobrevivencia, peso y talla se obtuvo con el alimento constituido por rotíferos enriquecidos con aceite de pescado (93 %,3.2mg, 6.86mm, seguido de rotíferos + algas (80.67 %,2 mg, 6.1mm y Artemia+ Spirulina (60.6 %,1.6mg, 6.06mm respectivamenteIn the Tropical Piscicultural Institute of the Regional Autonomous Corporation of Buga, Cauca, Valley, Colombia (25ºC temperature, 969 m a s l, a research was carried out with the objective to produce and use algaes and rotifers (living food cultures to feed bocachico post-larvas (Prochilodus reticulatus magdalenae. A complete random design with three treatments and three repetitions was established. 100 bocachico/aquarium post larva were used and fed twice a day according to sown biomass. The cultures of mixed algaes were established by using inorganic fertilizers produced in plastic pails and obtaining an average of 386 x 10³ cells/ml of culture. On the other hand, the cultures of Philodina rotifers were established in glass bottles and feeding them with algaes and yeast. An average of 410 rotifers/ml of culturing was obtained . To evaluate the highest rate of survival, growing and weight of bocachico post-larvas, three kind of food were used: Rotifers enriched with fish oil; rotifers plus

  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. Effects of moisture content of food waste on residue separation, larval growth and larval survival in black soldier fly bioconversion.

    Science.gov (United States)

    Cheng, Jack Y K; Chiu, Sam L H; Lo, Irene M C

    2017-09-01

    In order to foster sustainable management of food waste, innovations in food waste valorization technologies are crucial. Black soldier fly (BSF) bioconversion is an emerging technology that can turn food waste into high-protein fish feed through the use of BSF larvae. The conventional method of BSF bioconversion is to feed BSF larvae with food waste directly without any moisture adjustment. However, it was reported that difficulty has been experienced in the separation of the residue (larval excreta and undigested material) from the insect biomass due to excessive moisture. In addition to the residue separation problem, the moisture content of the food waste may also affect the growth and survival aspects of BSF larvae. This study aims to determine the most suitable moisture content of food waste that can improve residue separation as well as evaluate the effects of the moisture content of food waste on larval growth and survival. In this study, pre-consumer and post-consumer food waste with different moisture content (70%, 75% and 80%) was fed to BSF larvae in a temperature-controlled rotary drum reactor. The results show that the residue can be effectively separated from the insect biomass by sieving using a 2.36mm sieve, for both types of food waste at 70% and 75% moisture content. However, sieving of the residue was not feasible for food waste at 80% moisture content. On the other hand, reduced moisture content of food waste was found to slow down larval growth. Hence, there is a trade-off between the sieving efficiency of the residue and the larval growth rate. Furthermore, the larval survival rate was not affected by the moisture content of food waste. A high larval survival rate of at least 95% was achieved using a temperature-controlled rotary drum reactor for all treatment groups. The study provides valuable insights for the waste management industry on understanding the effects of moisture content when employing BSF bioconversion for food waste recycling

  9. Food preference of red devil (Amphilophus labiatus) in the Sermo Reservoir, Kulon Progo Regency

    Science.gov (United States)

    Ariasari, A.; Helmiati, S.; Setyobudi, E.

    2018-03-01

    Food preference is one of the important information that can be used to know the food chain in order to manage fisheries resources. This study aims to determine the food habits and preference of red devil (Amphilophus labiatus) in the Sermo Reservoir, Kulon Progo Regency. Samples were collected randomly each month from September 2013 to February 2014. Each sample collected was measured its total length, body weight, and determined sex, then dissected to measure the gut length and to observe gut contents. Results showed that red devil is omnivorous (relative gut length = 3.83) with food composition consisted of fish, crustaceans, detritus, phytoplankton, zooplankton, plants, insects, insect’s larvae, Chironomus sp., and annelids. A change occurred in the food preference of red devil, i.e. the young fish prefers to feed Chironomus sp. larvae (86.02 %) whereas the adult fish prefers fish/fish chunk (81.82 %). Trophic level status of red devil showed as carnivorous and niche overlapping between male and female of the adult.

  10. Development of cesium 137 plant uptake predicting model using geographical information systems

    International Nuclear Information System (INIS)

    Lomonos, O.V.

    2002-01-01

    Soil-plant system is a critical component of food chain in processes of Cs 137 migration. In this component it is possible to decrease greatly Cs 137 uptake in food chain. Development of Cs 137 migration model in soil-plant system enable to determine amount of Cs 137 in plant uptake and evaluate agricultural produce accordance with modern ecological requirements. Also this model can help with management of agricultural production. Geographical information systems (GIS) have a wide propagation in radioecology at present time. Models using GIS have several advantages: relative simplicity of evaluation, visualization of evaluated results etc. As a result, plots with possible Cs 137 uptake increasing could be easily discovered. Physical decay, Cs 137 sorption and fixation by soil, Cs 137 vertical migration in soil profile and plant uptake are the main components of the Cs 137 migration model in soil-plant system. Content of biologically available Cs 137 calculated taking into account all of these components. Using GIS with Cs 137 migration model in soil-plant system lets efficiently discover those factors that have major influence on Cs 137 plant uptake increasing. This model improves agricultural production on territories, which polluted by Cs 137

  11. PEMELIHARAAN LARVA IKAN KLOWN (Amphiprion percula DENGAN PAKAN ALAMI YANG BERBEDA

    Directory of Open Access Journals (Sweden)

    Ketut Maha Setiawati

    2016-11-01

    improve the color brightness on the hatchery produced seed. Therefore, this research was designed to evaluate the use of other live feed such as copepod to improve color brightness, growth, survival rate, performance, and vitality of clownfish. Larvae used for this research were reared until day 30. The research was conducted using fiberglass tank of 200 L volume and filled with 150 L sea water. Six days eggs were used in the experiment. Eggs density was 200 ind./tank. Larvae were fed either rotifer (A or rotifer + copepod (B as treatment. Each treatment has five replicates. The results showed that total length and body weight of larvae in each treatment were 9.15 ± 1.27mm and 9.2 ± 0.1 mg for treatment A, and 10.44 ± 0.24 mm and 15.2 ± 0.5 mg for treatment B. Visually, seed of treatment B had brighter color than treatment A. Vitality test was performed by dipping the seed in fresh water. It showed that seed of treatment B survived for 231.6 seconds, which was longer compared to treatment A which was only survived for 39.8 seconds in fresh water. It can be concluded that addition of copepod as live food for clown fish larvae enhance its growth, color brightness and vitality.

  12. Azadirachtin induced larval avoidance and antifeeding by disruption of food intake and digestive enzymes in Drosophila melanogaster (Diptera: Drosophilidae).

    Science.gov (United States)

    Bezzar-Bendjazia, Radia; Kilani-Morakchi, Samira; Maroua, Ferdenache; Aribi, Nadia

    2017-11-01

    Botanical insecticides are a promising alternative to reduce the harmful effects of synthetic chemicals. Among the botanical biopesticides, azadirachtin obtained from the Indian neem tree Azadirachta indica A. Juss. (Meliaceae) is probably the biorational insecticide with greatest agriculture use nowadays due to its broad insecticide activity. The current study, evaluated the lethal and sublethal effects of azadirachtin on larval avoidance, food intake and digestive enzymes of Drosophila melanogaster larvae as biological model. Azadirachtin was applied topically at two doses LD 25 (0.28μg) and LD 50 (0.67μg) on early third instars larvae. Results evaluated 24h after treatment showed that larvae exhibited significant repellence to azadirachtin and prefer keeping in untreated arenas rather than moving to treated one. In addition, azadirachtin avoidance was more marked in larvae previously treated with this compound as compared with naïf larvae (controls). Moreover, azadirachtin treatment decreased significantly the amount of larval food intake. Finally, azadirachtin reduced significantly the activity of larval α-amylase, chitinase and protease and increased the activity of lipase. This finding showed that azadirachtin induced behavioral and physiological disruption affecting the ability of the insect to digest food. This rapid installation of avoidance and long term antifeedancy might reinforce the action of azadirachtin and provide a new behavioral strategy for integrated pest management programs. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. 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.

  14. 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

  15. The uptake of uranium and radium from food and water in relation to calcium

    International Nuclear Information System (INIS)

    Wrenn, M.E.

    1988-01-01

    Observed ratios for dietary radium and calcium suggest that at least a 20 to 70 fold discrimination exists against radium uptake in the skeleton relative to calcium. It has been widely shown in many countries around the world that the relative radium to calcium ratio in the human skeleton varies from country to country, but within geographic areas, it appears to be relatively invariant with age. The ratio of radium-226 to calcium in intake, relative to the radium-226 to calcium value in the skeleton, is called the observed ratio, and varies over the world from a value of 0.013 to 0.039, with a mean of 0.024. In 1975, I inferred a mean observed ratio for uranium of 0.057 for the US. These findings suggest that man is in equilibrium with radium-226 with respect to the calcium in food and water. Most of the calcium would be ingested in diet, as would a significant amount, but not necessarily all, of the radium. The role of calcium for intake in water has not been examined

  16. Preliminary study on the inactivation of anisakid larvae in baccalà prepared according to traditional methods

    Directory of Open Access Journals (Sweden)

    Giorgio Smaldone

    2017-11-01

    Full Text Available The European Food Safety Authority stated that many traditional marinating and cold smoking methods are not sufficient to kill A. simplex and asked to evaluate alternative treatments for killing viable parasites in fishery. Baccalà is a well-liked traditional product. The aim of study was to evaluate the effectiveness of the salting process on the inactivation of nematodes of the genus Anisakis in naturally infected Baccalà fillets. N. 19 fillets, subjected to a dual salting process (brine and dry salting were analyzed. Visual inspection and chloropeptic digestion were performed. Larvae viability was evaluated, and parameters such as NaCl (%, moisture (%, WPS and aw were determined. In n. 17 samples parasites were found 123 parasites with a mean intensity of 7.23±4.78 and an mean abundance of 6.47±5.05. Visual examination has revealed 109 parasites. 61.8% of larvae were found in the ventral portions. The results show that salting process with a salt concentration of 18.6%, aw values of 0.7514 and 24.15% WPS in all parts of baccalà fillets, devitalise Anisakidae larvae in a 15-day period.

  17. Preliminary study on the inactivation of anisakid larvae in baccalà prepared according to traditional methods.

    Science.gov (United States)

    Smaldone, Giorgio; Marrone, Raffaele; Palma, Giuseppe; Sarnelli, Paolo; Anastasio, Aniello

    2017-10-20

    The European Food Safety Authority stated that many traditional marinating and cold smoking methods are not sufficient to kill A. simplex and asked to evaluate alternative treatments for killing viable parasites in fishery . Baccalà is a well-liked traditional product. The aim of study was to evaluate the effectiveness of the salting process on the inactivation of nematodes of the genus Anisakis in naturally infected Baccalà fillets. N. 19 fillets, subjected to a dual salting process (brine and dry salting) were analyzed. Visual inspection and chloropeptic digestion were performed. Larvae viability was evaluated, and parameters such as NaCl (%), moisture (%), WPS and a w were determined. In n. 17 samples parasites were found 123 parasites with a mean intensity of 7.23±4.78 and an mean abundance of 6.47±5.05. Visual examination has revealed 109 parasites. 61.8% of larvae were found in the ventral portions. The results show that salting process with a salt concentration of 18.6%, a w values of 0.7514 and 24.15% WPS in all parts of baccalà fillets, devitalise Anisakidae larvae in a 15-day period.

  18. 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.

  19. Automated culture of aquatic model organisms: shrimp larvae husbandry for the needs of research and aquaculture.

    Science.gov (United States)

    Mutalipassi, M; Di Natale, M; Mazzella, V; Zupo, V

    2018-01-01

    Modern research makes frequent use of animal models, that is, organisms raised and bred experimentally in order to help the understanding of biological and chemical processes affecting organisms or whole environments. The development of flexible, reprogrammable and modular systems that may help the automatic production of 'not-easy-to-keep' species is important for scientific purposes and for such aquaculture needs as the production of alive foods, the culture of small larvae and the test of new culture procedures. For this reason, we planned and built a programmable experimental system adaptable to the culture of various aquatic organisms, at different developmental stages. The system is based on culture cylinders contained into operational tanks connected to water conditioning tanks. A programmable central processor unit controls the operations, that is, water changes, temperature, light irradiance, the opening and closure of valves for the discharge of unused foods, water circulation and filtration and disinfection systems, according to the information received by various probes. Various devices may be set to modify water circulation and water changes to fulfil the needs of given organisms, to avoid damage of delicate structures, improve feeding performances and reduce the risk of movements over the water surface. The results obtained indicate that the system is effective in the production of shrimp larvae, being able to produce Hippolyte inermis post-larvae with low mortality as compared with the standard operation procedures followed by human operators. Therefore, the patented prototype described in the present study is a possible solution to automate and simplify the rearing of small invertebrates in the laboratory and in production plants.

  20. Uptake, localization and clearance of quantum dots in ciliated protozoa Tetrahymena thermophila

    International Nuclear Information System (INIS)

    Mortimer, Monika; Kahru, Anne; Slaveykova, Vera I.

    2014-01-01

    Protozoa as phagocytizing cells have been shown to integrate engineered nanoparticles (NPs), while the mechanism, dynamics and extent of such uptake are unclear. Here our fluorescence microscopy data showed that CdSe/ZnS quantum dots (QDs) with primary size of 12 nm were readily phagocytized into the food vacuoles of Tetrahymena thermophila in a time- and dose-dependent manner. Twenty hours after the exposure to QDs in sublethal concentration the clearance of the QDs from the cells was incomplete suggesting that phagocytosis of QDs into food vacuoles was not the only pathway of uptake by T. thermophila. This was further proven by the results that the inhibition of phagocytosis did not block the internalization of QDs into protozoans. This study provides a new insight into uptake and cellular trafficking of subtoxic concentrations of nanoparticles that may, due to prolonged retention times in the cells, pose risks by potentially becoming available to higher trophic levels. - Highlights: • Tetrahymena thermophila internalized QDs in a dose- and time-dependent manner. • The egested QDs were not significantly biodegraded in the food vacuoles. • In addition to phagocytosis QDs entered protozoa by alternative uptake pathways. • The clearance of the QDs from the cells was incomplete after 20 h in fresh medium. • The prolonged retention time of nontoxic NPs in protozoa could increase their transfer in food chain. - In addition to phagocytosis, quantum dots (QDs) entered protozoans by alternative pathways which did not lead to complete clearance of the QDs from the cells

  1. 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.

  2. 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

  3. 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.

  4. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm)

    Science.gov (United States)

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju

    2014-01-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions. PMID:25071922

  5. 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.

  6. 1 Food and Feeding Habits of the Guppy.cdr

    African Journals Online (AJOL)

    Administrator

    number of algae and mosquito larvae consumed, while there was no significant difference (P > 0.05) in the number of other food ..... Alae Diatoms Protozoans Mosquito Fish Crustanceans Organic Sand ... use of the fish for biological control of.

  7. 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)

  8. Evaluating Penetration Ability of Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) Larvae into Multilayer Polypropylene Packages.

    Science.gov (United States)

    Scheff, Deanna S; Sehgal, Blossom; Subramanyam, Bhadriraju

    2018-04-18

    The larvae of the Indian meal moth, Plodia interpunctella (Hübner), can invade or penetrate packaging materials and infest food products. Energy bars with three polypropylene packaging types were challenged with eggs (first instars), third instars, and fifth instars of P. interpunctella to determine package resistance at 28 °C and 65% r.h. The packing types were also challenged with two male and two female pupae of P. interpunctella under similar conditions in order to determine which package provided the greatest protection against larval penetration. Samples infested with eggs, third instars, and pupae were evaluated after 21 days and 42 days to count the number of larvae, pupae, and adults found inside the packages. Packages challenged with fifth instars were observed after 21 days to count the number of larvae, pupae, and adults inside each package. The number and diameter of the holes were determined in each package, followed by the amount of damage sustained to the energy bar. Third and fifth instars showed a higher tendency to penetrate all of the packaging types. First instars showed a reduction in package penetration ability compared with third and fifth instars. The increase in exposure time resulted in an increase in the damage sustained to the energy bars. Among packaging types, the thickest package (Test A) was most resilient to penetration by all of the larval stages. In conclusion, energy bar manufacturers need to invest more effort into improving packaging designs, creating thicker gauge films, or advancing odor barrier technology, in order to prevent penetration and infestation by P. interpunctella larvae.

  9. Evaluating Penetration Ability of Plodia interpunctella (Hübner (Lepidoptera: Pyralidae Larvae into Multilayer Polypropylene Packages

    Directory of Open Access Journals (Sweden)

    Deanna S. Scheff

    2018-04-01

    Full Text Available The larvae of the Indian meal moth, Plodia interpunctella (Hübner, can invade or penetrate packaging materials and infest food products. Energy bars with three polypropylene packaging types were challenged with eggs (first instars, third instars, and fifth instars of P. interpunctella to determine package resistance at 28 °C and 65% r.h. The packing types were also challenged with two male and two female pupae of P. interpunctella under similar conditions in order to determine which package provided the greatest protection against larval penetration. Samples infested with eggs, third instars, and pupae were evaluated after 21 days and 42 days to count the number of larvae, pupae, and adults found inside the packages. Packages challenged with fifth instars were observed after 21 days to count the number of larvae, pupae, and adults inside each package. The number and diameter of the holes were determined in each package, followed by the amount of damage sustained to the energy bar. Third and fifth instars showed a higher tendency to penetrate all of the packaging types. First instars showed a reduction in package penetration ability compared with third and fifth instars. The increase in exposure time resulted in an increase in the damage sustained to the energy bars. Among packaging types, the thickest package (Test A was most resilient to penetration by all of the larval stages. In conclusion, energy bar manufacturers need to invest more effort into improving packaging designs, creating thicker gauge films, or advancing odor barrier technology, in order to prevent penetration and infestation by P. interpunctella larvae.

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. Cs-134 transfer from water or food to the Ciprinid Tinca tinca Linnaeus: uptake and loss kinetics

    International Nuclear Information System (INIS)

    Corisco, J.A.G.; Carreiro, M.C.V.

    1991-01-01

    Experiments with 134 Cs and the fish Tinca tinca Linnaeus (fam. Cyprinidae), as a part of a more extensive work, concerning a simplified freshwater trophic chain using water from Fratel dam, (at Tejo River), were undertaken. Direct uptake from water, during a period of about 30 days, leads to a kinetics expressed by the power function: CF (t) = 0.58 t 0.781 (t in days), the concentration factor (CF) referred to wet weight. Retention study, showed the existence of two biological half-lives, Tb 1 = 7 days and Tb 2 = 87 days, which might concern respectively, the 134 Cs desorption from the transit organs and the loss of the assimilated isotope from the storage organs. In the accumulation through the food chain, using planktonic crustacean Daphnia magna Straus (Cladocera) as prey, a transfer factor (TF) related to wet weight of both fish and prey, is estimated through the power function: TF (t) = 0.022 t 0.578 (t in days). Finally, the retention study following the food pathway contamination, stresses the existence of one long term component, with half-life Tb = 61 days. The transfer factor kinetics seems to point out to a rather slow process, leading to lower 134 Cs concentration values, than the contamination through the water. The loss of the assimilated 134 Cs, uptaken through both pathways, water or food, is a slow process. The longer biological half-life is very important in Radiological Protection, once it may be attributed to the radionuclide loss from the muscular mass. (author)

  15. Biochemical abnormalities induced by abamectin in sixth instar larvae of the red flour beetle, tribolium castaneum (herbst)

    International Nuclear Information System (INIS)

    Hussain, R.

    2014-01-01

    The sub lethal effects of abamectin (Sure 1.8 EC) were studied on malathion-resistant (PAK) and organophosphate susceptible (FSS-II) strains of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) larvae in the laboratory. The objective was to examine changes in production or activities of carboxylesterase (CE), total esterases (TE), alpha-amylase, glucoamylase, alkaline phosphatase (AkP), acidic phosphatase (AcP), total protein, soluble protein and free amino acids (FAA). The sixth instar larvae of T. castaneum were released and exposed for 48h without food on abamectin treated glass petri dishes. The surviving ones were then homogenized in saline and centrifuged prior to biochemical analyses. Results showed differences in the activities of enzymes and quantities of total protein, soluble protein and FAA between strains and among concentrations. Abamectin, at LC and LC , changed the activities 10 20/levels of TE, CE, AcP, total protein and FAA in the larvae of both the strains. The activities of alpha-amylase, glucoamylase and AkP remained non-significant at both doses in the two strains. In PAK strain larvae, the TE activity was inhibited with depletion of total protein contents and elevation of FAA contents. In FSS-II larvae, the effect of abamectin on levels of alpha-amylase, glucoamylase, AkP, total protein and soluble protein remained non-significant. The activities of TE and AcP were reduced at both doses, while activities/levels of CE reduced at LC and FAA increased 10 at LC . It is concluded that abamectin affected the overall body 20 functioning of PAK strain more as compared to FSS-II strain considering disturbances caused in the levels/activities of biochemical components. (author)

  16. Behaviour and physiology shape the growth accelerations associated with predation risk, high temperatures and southern latitudes in Ischnura damselfly larvae.

    Science.gov (United States)

    Stoks, Robby; Swillen, Ine; De Block, Marjan

    2012-09-01

    1. To better predict effects of climate change and predation risk on prey animals and ecosystems, we need studies documenting not only latitudinal patterns in growth rate but also growth plasticity to temperature and predation risk and the underlying proximate mechanisms: behaviour (food intake) and digestive physiology (growth efficiency). The mechanistic underpinnings of predator-induced growth increases remain especially poorly understood. 2. We reared larvae from replicated northern and southern populations of the damselfly Ischnura elegans in a common garden experiment manipulating temperature and predation risk and quantified growth rate, food intake and growth efficiency. 3. The predator-induced and temperature-induced growth accelerations were the same at both latitudes, despite considerably faster growth rates in the southern populations. While the higher growth rates in the southern populations and the high rearing temperature were driven by both an increased food intake and a higher growth efficiency, the higher growth rates under predation risk were completely driven by a higher growth efficiency, despite a lowered food intake. 4. The emerging pattern that higher growth rates associated with latitude, temperature and predation risk were all (partly or completely) mediated by a higher growth efficiency has two major implications. First, it indicates that energy allocation trade-offs and the associated physiological costs play a major role both in shaping large-scale geographic variation in growth rates and in shaping the extent and direction of growth rate plasticity. Secondly, it suggests that the efficiency of energy transfer in aquatic food chains, where damselfly larvae are important intermediate predators, will be higher in southern populations, at higher temperatures and under predation risk. This may eventually contribute to the lengthening of food chains under these conditions and highlights that the prey identity may determine the influence of

  17. 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...

  18. Crescimento e estruturas do sistema digestório de larvas de pacu alimentadas com dieta microencapsulada produzida experimentalmente Growth and structure of the digestive system of pacu larvae fed microencapsulated diet produced experimentally

    Directory of Open Access Journals (Sweden)

    Olívia Cristina Camilo Menossi

    2012-01-01

    diets and an experimental microencapsulated diet produced by internal gelation were evaluated. Four-day old pacu larvae received the following treatments: only artemia nauplii in increasing amount during the experiment (positive control; larvae maintained at fasting (negative control; three types of formulated diets throughout the experiment (experimental microencapsulated diet, commercial diet NRD1.2/2.0, Inve, USA, and diet Poli-Peixe 450F, PoliNutri, Brazil; and three weaning protocols in which artemia nauplii were given from the 1st to 6th days, six days of co-feeding (artemia nauplii + the respective formulated diet, and only respective diets formulated after this period. The experiment was conducted for 23 days in a completely randomized design, with periodical evaluations of growth and digestive system. Survival rate was determined at the end of the experiment.The best performances of growth and survival, as well as the organogenesis of the digestive tract, were verified for the animals which received live feed. The larvae at weaning treatments induced intermediate growth and survival, which did not differ statistically between them. Considering the treatments that received only formulated diets as first feed, the PoliNutri diet was the unique that showed alive larvae at the end of experiment. None of the formulated diets are adequate as initial exogenous food for pacu larvae. During the weaning, the microencapsulated experimental diet provides growth and survival performances similar to those obtained with the commercial diets.

  19. 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...

  20. 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.

  1. 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

  2. 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.

  3. Substituição de alimento vivo por alimento inerte na larvicultura intensiva do tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v30i4.3835 Replacement of live food for inert food on larviculture of tambacu (♀ Colossoma macropomum X ♂ Piaractus mesopotamicus - DOI: 10.4025/actascianimsci.v30i4.3835

    Directory of Open Access Journals (Sweden)

    Levy de Carvalho Gomes

    2009-03-01

    Full Text Available Com este trabalho objetivou-se avaliar a substituição de náuplios de Artemia salina por alimentos inertes durante a larvicultura do tambacu. Na primeira fase, com duração de 12 dias, as larvas foram alimentadas com: náuplio de Artemia salina, cyclop-eeze e ovo de Artemia salina. Na segunda fase, com duração de dez dias, foram utilizadas larvas alimentadas com náuplios de Artemia salina provenientes da primeira fase e testados os mesmos três alimentos. A qualidade da água manteve-se em condições adequadas para a larvicultura nas duas fases. As larvas da primeira fase alimentadas com náuplios de Artemia salina obtiveram os melhores resultados em crescimento, sobrevivência e desempenho produtivo. Na segunda fase, o crescimento, a sobrevivência e o desempenho produtivo das larvas alimentadas com náuplios de Artemia salina e ovo de Artemia salina foram semelhantes. Nas duas fases, o custo com alimento foi mais baixo nas larvas alimentadas com náuplios de Artemia salina. Os resultados obtidos mostram que nas duas fases de larvicultura testadas a oferta de náuplios de Artemia salina é a melhor estratégia alimentar por proporcionar boa sobrevivência, crescimento e bom desempenho produtivo, além de menor custo.The aim of this work was to evaluate the replacement of Artemia salina nauplii by inert food during larviculture of tambacu. On the first phase with duration of 12 days, the larvae were fed with one of the following foods: Artemia salina nauplii, cyclop-eeze or Artemia salina egg. On the second phase, with 10 days of duration, larvae fed with Artemia salina nauplii were utilized in the first experiment and the same food treatments were tested. Water quality was adequate for larvae rearing in both phases. The larvae from the first phase that fed with Artemia salina nauplii presented better growth, survival rate and yield. On the second phase, the growth, survival and yield of larvae fed with Artemia salina nauplii and eggs

  4. Growth and Survival Rate of Tilapia (Oreochromis niloticus Larvae Fed by Daphnia magna Cultured With Organic Fertilizer Resulted From Probiotic Bacteria Fermentation

    Directory of Open Access Journals (Sweden)

    Vivi Endar Herawati

    2015-10-01

    Full Text Available Daphnia magna is a potential feed for fish. The aim of this research was to find the best treatment and effect of D. magna culture addition from fermented organic fertilizer, to growth and survival rate of Oreochromis niloticus larvae. There were five treatments, each with three repetitions used in the study. All treatments used chicken dung, and different combinations of rice bran, coconut oilcake waste and tilapia larvae. Feeding on tilapia was given by ad libitum method for five times a day until 14 days. Water quality during the research was maintained at temperature 28–29°C, DO 0.3 ppm and pH 8.1–8.2. Observed variables include relative growth rate, survival rate, food consumption rate and water quality. Our results showed that D. magna cultured by fermented organic fertilizer for tilapia larvae (O. niloticus had high significant effect (p < 0.01 on the relative growth rate and survival rate. Treatment of D. magna cultured by 1.2 g/L chicken manure, 0.9 g/L rice bran and 0.3 g/L coconut oilcake showed the highest value on the relative growth rate (10.86%; survival rate (98.46% and food consumption at first week (106.43% and second week (152.76%.

  5. Keefektivan Beauveria bassiana (Bals. Vuill. isolat Indigenous pagaralam sumatera selatan pada media beras terhadap larva Plutella xylostella Linn. (Lepidoptera: Yponomeutidae

    Directory of Open Access Journals (Sweden)

    Yulia Pudjiastuti

    2017-02-01

    Full Text Available The objective of study was to investigate the effectiveness of Beauveria bassiana isolate cultured in half-ripe rice media against third-instar larvae of Plutella xylostella. The research used 10 isolates consisted of 4 isolates that were originnally collected from Pagaralam i.e. PD1 (isolated from P. xylostella cadaver, PD2, PD8, PD9B (from Crysodeixis chalcites cadaver, and 6 isolates from other areas as comparison, i.e. CCW3 (from Crysodeixis chalcites cadaver, BBL (from Hypothenemus hampei cadaver, CH (from Conomorpha cramerella cadaver, CPJW (from H. hampei cadavi, WC (from Nilaparvata lugens cadaver, and WSJT (from Leptocorixa acuta cadaver. The parameters that were measured were mortality of larvae, time of death and behaviour of larvae after application. Result of the test showed that B. bassiana isolated from L. acuta (WSJT isolate caused the highest mortality i.e. 73.34 %, with the highest spore density 5.6x107 spore ml-1 (in half-rice media and 3.0x107 spore ml-1 (GYA media. The lowest LT50 was 19.27 hours, and was obtained from the application of PD9B. After application of B. bassiana, the behaviour of larvae was slightly change from a healthy one to less in consuming of food and then die.

  6. [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.

  7. 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...

  8. An unusual food plant for Cydia pomonella (Linnaeus (Lepidoptera, Tortricidae in Mexico

    Directory of Open Access Journals (Sweden)

    Alejandro Salinas-Castro

    2014-09-01

    Full Text Available An unusual food plant for Cydia pomonella (Linnaeus (Lepidoptera, Tortricidae in Mexico. Larvae of Cydia pomonella (Linnaeus, 1758 were discovered on floral cones of Magnolia schiedeana (Schltdl, 1864 near the natural reserve of La Martinica, Veracruz, México. Magnolia represents an unusual host for this moth species, which is known throughout the world as the "codling moth", a serious pest of fruits of Rosaceae, especially apples. The larvae were identified using taxonomic keys, and identification was corroborated using molecular markers. Further sampling resulted in no additional larvae, hence, the observation was probably that of an ovipositional error by the female, and M. schiedeana is not at risk of attack by this important moth pest.

  9. Reduced uptake of mass treatment for schistosomiasis control in absence of food

    DEFF Research Database (Denmark)

    Muhumuza, Simon; Olsen, Annette; Katahoire, Anne

    2015-01-01

    the other, in addition to the education messages, received a pre-treatment snack shortly before mass treatment. The uptake of praziquantel in the snack schools was 94 % compared to 79 % in the non-snack schools. During mass treatment in 2014, no snack was provided. We compared the uptake of praziquantel....... mansoni infection. RESULTS: Uptake of praziquantel reduced from 93.9 to 78.0 % (p = 0.002) in the snack schools but was unchanged in the non-schools 78.7 and 70.4 % (p = 0.176). The occurence of side-effects attributable to praziquantel increased from 34.4 to 61.2 % (p = 0.001) in the snack schools...... but was unchanged in the non-snack schools; 46.9 and 53.2 % (p = 0.443). Although the prevalence of S. mansoni infection increased in both the snack and non-snack schools, the differences did not reach statistical significance;1.3 and 7.5 % (p = 0.051) and 14.1 and 22.0 % (p = 0.141), respectively. Similarly...

  10. Effects of host plant and larval density on intraspecific competition in larvae of the emerald ash borer (Coleoptera: Buprestidae).

    Science.gov (United States)

    Duan, Jian J; Larson, Kristi; Watt, Tim; Gould, Juli; Lelito, Jonathan P

    2013-12-01

    Competition for food, mates, and space among different individuals of the same insect species can affect density-dependent regulation of insect abundance or population dynamics. The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of North American ash (Fraxinus spp.) trees, with its larvae feeding in serpentine galleries between the interface of sapwood and phloem tissues of ash trees. Using artificial infestation of freshly cut logs of green ash (Fraxinus pennsylvanica Marshall) and tropical ash (Fraxinus uhdei [Wenzig] Lingelsh) with a series of egg densities, we evaluated the mechanism and outcome of intraspecific competition in larvae of A. planipennis in relation to larval density and host plant species. Results from our study showed that as the egg densities on each log (1.5-6.5 cm in diameter and 22-25 cm in length) increased from 200 to 1,600 eggs per square meter of surface area, larval survivorship declined from ≍68 to 10% for the green ash logs, and 86 to 55% for tropical ash logs. Accordingly, larval mortality resulting from cannibalism, starvation, or both, significantly increased as egg density increased, and the biomass of surviving larvae significantly decreased on both ash species. When larval density was adjusted to the same level, however, larval mortality from intraspecific competition was significantly higher and mean biomasses of surviving larvae was significantly lower in green ash than in tropical ash. The role of intraspecific competition of A. planipennis larvae in density-dependent regulation of its natural population dynamics is discussed.

  11. Uptake of phenolic compounds from plant foods in human intestinal ...

    Indian Academy of Sciences (India)

    Gavirangappa Hithamani

    Open-pan boiling reduced the uptake of quercetin from the onion. Among pure phenolic ... vegetable, is a major source of flavonoid in the diet (Galdón et al. 2008). ..... inflammatory and anti-atherosclerotic properties of red wine polyphenolic ... quercetin and quercetin-rich red onion extract on skeletal muscle mitochondria ...

  12. The role of pH in structuring communities of Maine wetland macrophytes and chironomid larvae (Diptera)

    Science.gov (United States)

    Woodcock, T.S.; Longcore, J.R.; McAuley, D.G.; Mingo, T.M.; Bennatti, C.R.; Stromborg, K.L.

    2005-01-01

    Aquatic vascular plants, or macrophytes, are an important habitat component for many wetland organisms, and larvae of chironomid midges are ubiquitous components of wetland fauna. Many chironomids are primary consumers of algae and detritus and form an essential energetic link between allochthonous and autochthonous primary production and higher trophic levels, while others are predators and feed on smaller invertebrates. Live macrophytes serve mostly as habitat, whereas plant detritus serves as both habitat and as a food source. Assemblages of macrophytes and chironomid larvae were surveyed in ten Maine wetlands, five with low pH (5.5), and explained in terms of physical and chemical habitat variables. Macrophyte richness was significantly greater, and richness of chironomid larvae was lower, in low pH wetlands. There was no difference in chironomid abundance related to pH. However, community structure was related to pH, suggesting that competitive dominance of a few taxa was responsible for lower richness in low pH wetlands, whereas competition was weaker in high pH wetlands, making coexistence of more chironomid taxa possible. An examination of individual chironomid taxa by stepwise multiple regression showed that distribution of most taxa was controlled by water chemistry variables and macrophyte habit (i.e., floating, submergent).

  13. Larval development and metamorphosis of Balanus albicostatus (Cirripedia: Thoracica); implications of temperature, food concentration and energetics

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Khandeparker, L.; Shirayama, Y.

    The influence of food concentrations (0.5, 1 and 2 x 105 cells ml sup(-1)) and temperatures (20 and 30 degrees C) on the survival, development, organic carbon and nitrogen content of Balanus albicostatus larvae was evaluated The effect of food...

  14. 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.

  15. Methylmercury enters an aquatic food web through acidophilic microbial mats in Yellowstone National Park, Wyoming.

    Science.gov (United States)

    Boyd, Eric S; King, Susan; Tomberlin, Jeffery K; Nordstrom, D Kirk; Krabbenhoft, David P; Barkay, Tamar; Geesey, Gill G

    2009-04-01

    Microbial mats are a visible and abundant life form inhabiting the extreme environments in Yellowstone National Park (YNP), WY, USA. Little is known of their role in food webs that exist in the Park's geothermal habitats. Eukaryotic green algae associated with a phototrophic green/purple Zygogonium microbial mat community that inhabits low-temperature regions of acidic (pH approximately 3.0) thermal springs were found to serve as a food source for stratiomyid (Diptera: Stratiomyidae) larvae. Mercury in spring source water was taken up and concentrated by the mat biomass. Monomethylmercury compounds (MeHg(+)), while undetectable or near the detection limit (0.025 ng l(-1)) in the source water of the springs, was present at concentrations of 4-7 ng g(-1) dry weight of mat biomass. Detection of MeHg(+) in tracheal tissue of larvae grazing the mat suggests that MeHg(+) enters this geothermal food web through the phototrophic microbial mat community. The concentration of MeHg(+) was two to five times higher in larval tissue than mat biomass indicating MeHg(+) biomagnification occurred between primary producer and primary consumer trophic levels. The Zygogonium mat community and stratiomyid larvae may also play a role in the transfer of MeHg(+) to species in the food web whose range extends beyond a particular geothermal feature of YNP.

  16. 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...

  17. 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...

  18. Metamorphosis alters contaminants and chemical tracers in insects: implications for food webs.

    Science.gov (United States)

    Kraus, Johanna M; Walters, David M; Wesner, Jeff S; Stricker, Craig A; Schmidt, Travis S; Zuellig, Robert E

    2014-09-16

    Insects are integral to most freshwater and terrestrial food webs, but due to their accumulation of environmental pollutants they are also contaminant vectors that threaten reproduction, development, and survival of consumers. Metamorphosis from larvae to adult can cause large chemical changes in insects, altering contaminant concentrations and fractionation of chemical tracers used to establish contaminant biomagnification in food webs, but no framework exists for predicting and managing these effects. We analyzed data from 39 studies of 68 analytes (stable isotopes and contaminants), and found that metamorphosis effects varied greatly. δ(15)N, widely used to estimate relative trophic position in biomagnification studies, was enriched by ∼ 1‰ during metamorphosis, while δ(13)C used to estimate diet, was similar in larvae and adults. Metals and polycyclic aromatic hydrocarbons (PAHs) were predominantly lost during metamorphosis leading to ∼ 2 to 125-fold higher larval concentrations and higher exposure risks for predators of larvae compared to predators of adults. In contrast, manufactured organic contaminants (such as polychlorinated biphenyls) were retained and concentrated in adults, causing up to ∼ 3-fold higher adult concentrations and higher exposure risks to predators of adult insects. Both food web studies and contaminant management and mitigation strategies need to consider how metamorphosis affects the movement of materials between habitats and ecosystems, with special regard for aquatic-terrestrial linkages.

  19. A review and model assessment of 32P and 33P uptake to biota in freshwater systems

    International Nuclear Information System (INIS)

    Smith, J.T.; Bowes, M.J.; Cailes, C.R.

    2011-01-01

    Bioaccumulation of key short-lived radionuclides such as 131 I and 32,33 P may be over-estimated since concentration ratios (CRs) are often based on values for the corresponding stable isotope which do not account for radioactive decay during uptake via the food chain. This study presents estimates for bioaccumulation of radioactive phosphorus which account for both radioactive decay and varying ambient levels of stable P in the environment. Recommended interim CR values for radioactive forms of P as a function of bioavailable stable phosphorus in the water body are presented. Values of CR are presented for three different trophic levels of the aquatic food chain; foodstuffs from all three trophic levels may potentially be consumed by humans. It is concluded that current recommended values of the CR are likely to be significantly over-estimated for radioactive phosphorus in many freshwater systems, particularly lowland rivers. Further research is recommended to field-validate these models and assess their uncertainty. The relative importance of food-chain uptake and direct uptake from water are also assessed from a review of the literature. It can be concluded that food-chain uptake is the dominant accumulation pathway in fish and hence accumulation factors for radioactive phosphorus in farmed fish are likely to be significantly lower than those for wild fish. - Highlights: → A model is developed for radiophosphorus uptake to fish. → Concentration ratios for 32,33 P in fish may be over-estimated in freshwater systems. → New recommended values for 32,33 P concentration ratios are given. → Farmed fish are likely to have much lower 32,33 P uptake than wild fish.

  20. 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

  1. 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.

  2. 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...

  3. 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.

  4. Life history traits and the activity of antioxidative enzymes in Lymantria dispar L. (lepidoptera, lymantriidae) larvae exposed to benzo[a]pyrene.

    Science.gov (United States)

    Ilijin, Larisa; Mrdaković, Marija; Todorović, Dajana; Vlahović, Milena; Gavrilović, Anja; Mrkonja, Aleksandra; Perić-Mataruga, Vesna

    2015-11-01

    Increased presence of benzo[a]pyrene in the environment underlines the need for development of sensitive biomarkers for monitoring. Antioxidative enzymes could be used as early-warning signals because of their sensitivity and applicability. The activity of 2 antioxidative enzymes, superoxide dismutase (SOD) and catalase (CAT), were measured in midgut tissues of fifth instar Lymantria dispar larvae exposed to different concentrations of benzo[a]pyrene: 2 ng, 10 ng, 20 ng, 100 ng, 200 ng, and 2000 ng benzo[a]pyrene/g dry food weight. Larval development, larval mass, and relative growth rate were also monitored. The authors detected prolonged larval development, as well as reduced larval mass and relative growth rate in larvae exposed to all benzo[a]pyrene concentrations. The L. dispar midgut SOD activity was significantly increased, and 2 SOD isoforms were detected on native polyacrylamide gel electrophoresis in larvae fed on artificial diet supplemented with benzo[a]pyrene. In contrast, the control group had only 1 isoform. Catalase activity was significantly increased in all benzo[a]pyrene-treated larvae. Native gel electrophoresis showed that a switch in active CAT isoforms occurred after benzo[a]pyrene treatment. Thus, SOD and CAT in polyphagous herbivorous L. dispar larvae are very sensitive to low concentrations of benzo[a]pyrene. Therefore, they could be used as biomarkers for exposure and effects of this toxic polycyclic aromatic hydrocarbon. © 2015 SETAC.

  5. TEKNOLOGI PEMELIHARAAN LARVA KERAPU SUNU (Plectropomus leopardus SECARA MASSAL

    Directory of Open Access Journals (Sweden)

    Titiek Aslianti

    2016-12-01

    Seed production technology of leopard coral trout, Plectropomus leopardus by improving hatchery management had been conducted in order to increase survival rate and to produce seed continuity. The initial feeding can successfully support in larval rearing. Feed organism as rotifer, trochophore gonad, egg yolk emulsion, and artificial feed emulsion, had been used as an initial feed. The twelve of concrete tanks with 6 m3 capacity were stocked with coral trout eggs at density 100,000—150,000 eggs/tank. Artemia nauplii, artificial feed, and mysid as feed, start on larvae D20 up to juvenile stage (D45. Growth rate and survival rate were observed and calculated when the experiment was terminated. The data was analyzed by descriptive. Nutrition value of food was analyzed by proximate and fatty acid composition. The others parameters such as deformity and water quality were observed. The result showed that artificial feed emulsion and egg yolk emulsion as an initial feeding can be improve the growth rate and increase survival rate of larvae. The range of total length, body weight and survival rate of the seed i.e. 1.95—2.85 cm; 0.64—0.73 g, and 0.25%— 3.97% with the daily growth rate 3,9%—4,22%, respectively. No back bone deformity in the seed, that is 21—23 segments with interspaces of segments 0.030—0.036 mm.

  6. The role of iron uptake in pathogenicity and symbiosis in Photorhabdus luminescens TT01

    Directory of Open Access Journals (Sweden)

    Joyce Susan A

    2010-06-01

    Full Text Available Abstract Background Photorhabdus are Gram negative bacteria that are pathogenic to insect larvae whilst also having a mutualistic interaction with nematodes from the family Heterorhabditis. Iron is an essential nutrient and bacteria have different mechanisms for obtaining both the ferrous (Fe2+ and ferric (Fe3+ forms of this metal from their environments. In this study we were interested in analyzing the role of Fe3+ and Fe2+ iron uptake systems in the ability of Photorhabdus to interact with its invertebrate hosts. Results We constructed targeted deletion mutants of exbD, feoABC and yfeABCD in P. luminescens TT01. The exbD mutant was predicted to be crippled in its ability to obtain Fe3+ and we show that this mutant does not grow well in iron-limited media. We also show that this mutant was avirulent to the insect but was unaffected in its symbiotic interaction with Heterorhabditis. Furthermore we show that a mutation in feoABC (encoding a predicted Fe2+ permease was unaffected in both virulence and symbiosis whilst the divalent cation transporter encoded by yfeABCD is required for virulence in the Tobacco Hornworm, Manduca sexta (Lepidoptera but not in the Greater Wax Moth, Galleria mellonella (Lepidoptera. Moreover the Yfe transporter also appears to have a role during colonization of the IJ stage of the nematode. Conclusion In this study we show that iron uptake (via the TonB complex and the Yfe transporter is important for the virulence of P. luminescens to insect larvae. Moreover this study also reveals that the Yfe transporter appears to be involved in Mn2+-uptake during growth in the gut lumen of the IJ nematode. Therefore, the Yfe transporter in P. luminescens TT01 is important during colonization of both the insect and nematode and, moreover, the metal ion transported by this pathway is host-dependent.

  7. 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.

  8. Biological uptake and transfer of radium-226: a review

    International Nuclear Information System (INIS)

    Williams, A.R.

    1982-01-01

    The theoretical basis of the biological uptake of radium is poorly developed. The simple linear concentration factor model has been used almost exclusively and often without any appreciation of its limitations. An analysis of the available data reveals that this model can be adequately validated only for freshwater algae. Deviations from this model are due to non-linearity of uptake response to increased radium concentration in the medium, to the lack of equilibrium being established within the time scale of the food-chain transfer, and to the existence of multiple sources (e.g. food and water) in some of the food-chain compartments. These theoretical weaknesses and the large errors of prediction indicate a need for more rigorous theoretical and experimental work. This need is further supported by the revised dose limits for the long-lived daughter products of uranium recently recommended by the International Commission on Radiological Protection (ICRP). These revised limits suggest that 226 Ra may no longer be a singularly critical nuclide, and thus dose assessment models will have to incorporate more radionuclide transfer terms, for which the errors are additive, and so should be made as low as possible. (author)

  9. Multilocus sequence typing, biochemical and antibiotic resistance characterizations reveal diversity of North American strains of the honey bee pathogen Paenibacillus larvae.

    Science.gov (United States)

    Krongdang, Sasiprapa; Evans, Jay D; Pettis, Jeffery S; Chantawannakul, Panuwan

    2017-01-01

    Paenibacillus larvae is a Gram positive bacterium and the causative agent of the most widespread fatal brood disease of honey bees, American foulbrood (AFB). A total of thirty-three independent Paenibacillus larvae isolates from various geographical origins in North America and five reference strains were investigated for genetic diversity using multilocus sequence typing (MLST). This technique is regarded to be a powerful tool for epidemiological studies of pathogenic bacteria and is widely used in genotyping assays. For MLST, seven housekeeping gene loci, ilvD (dihydroxy-acid dyhydrogenase), tri (triosephosphate isomerase), purH (phospharibosyl-aminoimidazolecarboxamide), recF (DNA replication and repair protein), pyrE (orotate phosphoribosyltransferase), sucC (succinyl coenzyme A synthetase β subunit) and glpF (glycerol uptake facilitator protein) were studied and applied for primer designs. Previously, ERIC type DNA fingerprinting was applied to these same isolates and the data showed that almost all represented the ERIC I type, whereas using BOX-PCR gave an indication of more diversity. All isolates were screened for resistance to four antibiotics used by U.S. beekeepers, showing extensive resistance to tetracycline and the first records of resistance to tylosin and lincomycin. Our data highlight the intraspecies relationships of P. larvae and the potential application of MLST methods in enhancing our understanding of epidemiological relationships among bacterial isolates of different origins.

  10. Multilocus sequence typing, biochemical and antibiotic resistance characterizations reveal diversity of North American strains of the honey bee pathogen Paenibacillus larvae.

    Directory of Open Access Journals (Sweden)

    Sasiprapa Krongdang

    Full Text Available Paenibacillus larvae is a Gram positive bacterium and the causative agent of the most widespread fatal brood disease of honey bees, American foulbrood (AFB. A total of thirty-three independent Paenibacillus larvae isolates from various geographical origins in North America and five reference strains were investigated for genetic diversity using multilocus sequence typing (MLST. This technique is regarded to be a powerful tool for epidemiological studies of pathogenic bacteria and is widely used in genotyping assays. For MLST, seven housekeeping gene loci, ilvD (dihydroxy-acid dyhydrogenase, tri (triosephosphate isomerase, purH (phospharibosyl-aminoimidazolecarboxamide, recF (DNA replication and repair protein, pyrE (orotate phosphoribosyltransferase, sucC (succinyl coenzyme A synthetase β subunit and glpF (glycerol uptake facilitator protein were studied and applied for primer designs. Previously, ERIC type DNA fingerprinting was applied to these same isolates and the data showed that almost all represented the ERIC I type, whereas using BOX-PCR gave an indication of more diversity. All isolates were screened for resistance to four antibiotics used by U.S. beekeepers, showing extensive resistance to tetracycline and the first records of resistance to tylosin and lincomycin. Our data highlight the intraspecies relationships of P. larvae and the potential application of MLST methods in enhancing our understanding of epidemiological relationships among bacterial isolates of different origins.

  11. Limnoperna fortunei Dunker, 1857 larvae in different environments of a Neotropical floodplain: relationships of abiotic variables and phytoplankton with different stages of development

    Directory of Open Access Journals (Sweden)

    J. Ernandes-Silva

    Full Text Available Abstract Limnoperna fortunei Dunker, 1857 is an Asian invasive freshwater bivalve. Although there need to contain their spread, studies about the biology of the larvae are scarce. We correlated the larval stages of L. fortunei with biotic factors such as phytoplankton and main abiotic variables in lotic environments of the Upper Paraná River floodplain. The four samples were taken quarterly during the year 2012. The Principal component analysis (PCA showed only spatial differences, as did a Canonical Correspondence Analysis (CCA. High densities of larvae were recorded in all samples the Paraná River and Baía River only in December, especially those in their initial stage. In the biovolume of Class of algae, Bacillarophyceae showed the highest value, but Chlorophycea who was strongly correlated with the density of D-stage larvae. The large variety of phytoplankton, especially microplankton Chlorophyceae, high values of PO4, NH4 and temperature were positively correlated with high densities of D-stage larvae. We conclude that high temperature, and food availability, indicated by phytoplankton community, favored the reproduction of L. fortunei and enhance the ability of specie dispersion due to the increase in the emission of propagules. Therefore, studies that address the biology of golden mussel larvae should be performed in order to prevent its spread.

  12. 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...

  13. 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.

  14. [Composition, distribution and abundance of gastropod larvae in the South of Quintana Roo,Mexico and north of Belice].

    Science.gov (United States)

    Oliva Rivera, J; de Jesús Navarrete, A

    2000-12-01

    To know the composition, abundance and distribution of gastropod larvae, monthly samplings were carried out in the south of Quintana Roo, Mexico and north of Belize, from April to December, 1996. Collections were made in six sites at Chinchorro Bank, four in the South Coast and six at Hol-Chan, Belize, between the 10 and 20 hrs. At each station 2.5 m3 of seawater were pumped through a 202 microns mesh; 27 species were identified. The most abundant species were: South Coast, Rissoina sp. 1., Limacina sp. 1 and Natica sp. 1, Chinchorro Bank, Limacina sp. 1, Creseis acicula, Cerithiopsis hero and Rissoina sp. 1 and Hol-Chan, Limacina sp. 2, Alaba incerta and Rissoina sp. 1. The highest abundance was in rainy season. Apparently the presence of winds, coastal currents and food availability, control the distribution and abundance of larvae.

  15. 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.

  16. 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.

  17. 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.

  18. /sup 75/Se-methionine uptake in the pancreas. An experimental investigation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Lewander, R [Danderyds Sjukhus, Stockholm (Sweden)

    1975-11-01

    Measurements of the uptake of /sup 75/Se-methionine in the abdominal visceral organs of mice indicate that amino acids (Aminosol) significantly increase the accumulation of the isotope in pancreas. Similarly, a beneficial effect is observed on the distribution of activity between pancreas and blood, while withdrawal of food adversely affects the uptake in the pancreas and gastro-intestinal tract.

  19. Effect of Different Medium on Survival Rate and Growth of Chironomus sp. Larvae

    Directory of Open Access Journals (Sweden)

    . Widanarni

    2007-07-01

    Full Text Available In the ornamental fish and fish for food culture, feeding by natural feed is very suitable since they are easy to digest and their size is suitable with  to larval mouth.  One of natural foods is blood worm Chironomus sp. larvae that has high protein content (till  65.2% of  protein. Until now, blood worm is obtained from nature and their stock depends on the weather.  That problem  may be overcome by culturing blood worm in appropriate culture medium.  Naturally, Chironomus sp. grows well in the water containing sago waste.  This study was carried out to examine the growth of Chironomus sp. reared in the medium containing mud, solid sago waste, solid tapioca wastes and water with no waste in depth of 0.5 cm. After 35-day rearing, survival rate of Chironomus sp was different among the treatments, while growth in length was similar. The best survival rate, 58.93% was obtained in the media containing solid sago waste.   Keywords: Chironomus, blood worm, sago waste, tapioca waste   ABSTRAK Dalam usaha budidaya ikan hias maupun ikan konsumsi, pemberian pakan alami sangat cocok karena mudah dicerna dan sesuai dengan bukaan mulut larva. Salah satu contoh pakan alami adalah Chironomus sp. (blood worm yang mempunyai kandungan protein mencapai 65,2%. Selama ini cacing darah diperoleh dari alam dan suplainya tergantung pada kondisi musim. Hal ini mungkin dapat diatasi dengan membudidayakan cacing darah dengan  media yang sesuai sebagai tempat hidupnya. Secara alami, Chironomus sp. dapat tumbuh dan berkembang dengan baik pada limbah sagu. Penelitian ini dilakukan untuk mengetahui pertumbuhan Chironomus sp. yang dipelihara pada media berupa lumpur, limbah sagu padat, limbah tapioka padat dan air tanpa limbah dengan ketebalan media 0,5 cm. Setelah 35 hari masa pemeliharaan, diketahui bahwa penggunaan media limbah padat sagu, limbah padat tapioka, lumpur dan air tanpa limbah pada pemeliharaan Chironomus sp. masing-masing menghasilkan tingkat

  20. Postprandial triacylglycerol uptake in the legs is increased during exercise and post-exercise recovery

    DEFF Research Database (Denmark)

    Enevoldsen, L H; Simonsen, L; Bülow, J

    2005-01-01

    plasma triacylglycerol (TAG) uptake and clearance in the exercising legs immediately and for at least 4 h post-exercise, while food intake per se did not change leg plasma TAG uptake or clearance for up to 6 h. It is hypothesized that the effect of exercise on leg plasma TAG metabolism is a result...

  1. 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],...

  2. 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],...

  3. 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],...

  4. 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],...

  5. 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],...

  6. 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],...

  7. 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],...

  8. 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],...

  9. 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],...

  10. 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],...

  11. 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],...

  12. 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],...

  13. 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],...

  14. 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],...

  15. 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],...

  16. 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],...

  17. 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],...

  18. 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],...

  19. 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],...

  20. 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],...

  1. 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],...

  2. 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],...

  3. 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],...

  4. 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],...

  5. 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],...

  6. 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],...

  7. 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],...

  8. 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],...

  9. 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],...

  10. 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],...

  11. 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],...

  12. Life-table studies revealed significant effects of deforestation on the development and survivorship of Anopheles minimus larvae.

    Science.gov (United States)

    Wang, Xiaoming; Zhou, Guofa; Zhong, Daibin; Wang, Xiaoling; Wang, Ying; Yang, Zhaoqing; Cui, Liwang; Yan, Guiyun

    2016-06-06

    Many developing countries are experiencing rapid ecological changes such as deforestation and shifting agricultural practices. These environmental changes may have an important consequence on malaria due to their impact on vector survival and reproduction. Despite intensive deforestation and malaria transmission in the China-Myanmar border area, the impact of deforestation on malaria vectors in the border area is unknown. We conducted life table studies on Anopheles minimus larvae to determine the pupation rate and development time in microcosms under deforested, banana plantation, and forested environments. The pupation rate of An. minimus was 3.8 % in the forested environment. It was significantly increased to 12.5 % in banana plantations and to 52.5 % in the deforested area. Deforestation reduced larval-to-pupal development time by 1.9-3.3 days. Food supplementation to aquatic habitats in forested environments and banana plantations significantly increased larval survival rate to a similar level as in the deforested environment. Deforestation enhanced the survival and development of An. minimus larvae, a major malaria vector in the China-Myanmar border area. Experimental determination of the life table parameters on mosquito larvae under a variety of environmental conditions is valuable to model malaria transmission dynamics and impact by climate and environmental changes.

  13. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    Energy Technology Data Exchange (ETDEWEB)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca

    2015-04-15

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml{sup −1} BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout.

  14. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    International Nuclear Information System (INIS)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M.

    2015-01-01

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml −1 BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout

  15. Prevalence and intensity of third stage Gnathostoma spinigerum larvae in swamp eels sold in three large markets in Bangkok, Thailand.

    Science.gov (United States)

    Saksirisampant, Wilai; Nuchprayoon, Surang; Wiwanitkit, Viroj; Kraivichian, Kanyarat; Suwansaksri, Jamsai

    2002-01-01

    Gnathostoma spinigerum is a common human tissue parasite in Thailand. The swamp eel is the major intermediate or paratenic host for this parasite. The high prevalence of the infective third stage larvae (L3) of this parasite in the rainy season has been noted in previous studies. During June 1999 (rainy season), we performed a cross-sectional survey of the prevalence and the intensity of G. spinigerum L3s in the livers of swamp eels that were obtained from three large Bangkok markets (Klong Toey, Pran Nok, and Tevej). Of a total of 785 livers, G. spinigerum L3s were found in 97: an infection rate of 12%. The prevalence rates in Klong Toey, Pran Nok, and Tevej markets were 13%, 10% and 14% respectively. There was no significant difference in the proportion of infected eels between the markets (p > 0.05). The intensity of L3 burden in the livers ranged from 1-17 larvae, with an average of 2.60 +/- 0.24 larvae (mean +/- SE). In this study a high prevalence of G. spinigerum L3s was found; there was no significant difference in the intensity of larvae in swamp eels between markets. These findings emphasize the importance of public health education: people need to be aware of the dangers of consuming raw or undercooked food.

  16. 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.

  17. 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.

  18. Tyramine functions as a toxin in honey bee larvae during Varroa-transmitted infection by Melissococcus pluton.

    Science.gov (United States)

    Kanbar, G; Engels, W; Nicholson, G J; Hertle, R; Winkelmann, G

    2004-05-01

    From wounds of honey bee pupae, caused by the mite Varroa destructor, coccoid bacteria were isolated and identified as Melissococcus pluton. The bacterial isolate was grown anaerobically in sorbitol medium to produce a toxic compound that was purified on XAD columns, gelfiltration and preparative HPLC. The toxic agent was identified by GC-MS and FTICR-MS as tyramine. The toxicity of the isolated tyramine was tested by a novel mobility test using the protozoon Stylonychia lemnae. A concentration of 0.2 mg/ml led to immediate inhibition of mobility. In addition the toxicity was studied on honey bee larvae by feeding tyramine/water mixtures added to the larval jelly. The lethal dosis of tyramine on 4-5 days old bee larvae was determined as 0.3 mg/larvae when added as a volume of 20 microl to the larval food in brood cells. Several other biogenic amines, such as phenylethylamine, histamine, spermine, cadaverine, putrescine and trimethylamine, were tested as their hydrochloric salts for comparison and were found to be inhibitory in the Stylonychia mobility test at similar concentrations. A quantitative hemolysis test with human red blood cells revealed that tyramine and histamine showed the highest membranolytic activity, followed by the phenylethylamine, trimethylamine and spermine, while the linear diamines, cadaverine and putrescine, showed a significantly lower hemolysis when calculated on a molar amine basis. The results indicate that tyramine which is a characteristic amine produced by M. pluton in culture, is the causative agent of the observed toxic symptoms in bee larvae. Thus this disease, known as European foulbrood, is possibly an infection transmitted by the Varroa destructor mite.

  19. 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.

  20. 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.

  1. 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.

  2. Indian meal moth (Plodia interpunctella)-resistant food packaging film development using microencapsulated cinnamon oil.

    Science.gov (United States)

    Kim, In-Hah; Song, Ah Young; Han, Jaejoon; Park, Ki Hwan; Min, Sea C

    2014-10-01

    Insect-resistant laminate films containing microencapsulated cinnamon oil (CO) were developed to protect food products from the Indian meal moth (Plodia interpunctella). CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to a low-density polyethylene (LDPE) film as an ink coating. The coated LDPE surface was laminated with a polypropylene film. The laminate film impeded the invasion of moth larvae and repelled the larvae. The periods of time during which cinnamaldehyde level in the film remained above a minimum repelling concentration, predicted from the concentration profile, were 21, 21, and 10 d for cookies, chocolate, and caramel, respectively. Coating with microencapsulated ink did not alter the tensile or barrier properties of the laminate film. Microencapsulation effectively prevented volatilization of CO. The laminate film can be produced by modern film manufacturing lines and applied to protect food from Indian meal moth damage. The LDPE-PP laminate film developed using microencapsulated cinnamon oil was effective to protect the model foods from the invasion of Indian meal moth larvae. The microencapsulated ink coating did not significantly change the tensile and barrier properties of the LDPE-PP laminate film, implying that replacement of the uncoated with coated laminate would not be an issue with current packaging equipment. The films showed the potential to be produced in commercial film production lines that usually involve high temperatures because of the improved thermal stability of cinnamon oil due to microencapsulation. The microencapsulated system may be extended to other food-packaging films for which the same ink-printing platform is used. © 2014 Institute of Food Technologists®

  3. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio Using a GFP-Tagged Yersinia ruckeri.

    Directory of Open Access Journals (Sweden)

    Rozalia Korbut

    Full Text Available Immersion-vaccines (bacterins are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr. During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant received a bath in the bacterin for up to 30 minutes. Samples were taken after 1 min, 15 min, 30 min, 2 h, 12 h and 24 h. At each sampling point fish were used for live imaging of the uptake using a fluorescence stereomicroscope and for immunohistochemistry (IHC. In adult fish, the bacterin could be traced within 30 min in scale pockets, skin, oesophagus, intestine and fins. Within two hours post bath (pb Yr-antigens were visible in the spleen and at 24 h in liver and kidney. Bacteria were associated with the gills, but uptake at this location was limited. Antigens were rarely detected in the blood and never in the nares. In juvenile fish uptake of the bacterin was seen in the intestine 30 min pb and in the nares 2 hpb but never in scale pockets. Antigens were detected in the spleen 12 hpb. Zebrafish larvae exhibited major Yr uptake only in the mid-intestine enterocytes 24 hpb. The different life stages of zebrafish varied with regard to uptake locations, however the gut was consistently a major uptake site. Zebrafish and rainbow trout tend to have similar uptake mechanisms following immersion or bath vaccination, which points towards zebrafish as a suitable model organism for this aquacultured species.

  4. 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

  5. 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.

  6. Pesticide uptake in potatoes: model and field experiments.

    Science.gov (United States)

    Juraske, Ronnie; Vivas, Carmen S Mosquera; Velásquez, Alexander Erazo; Santos, Glenda García; Moreno, Mónica B Berdugo; Gomez, Jaime Diaz; Binder, Claudia R; Hellweg, Stefanie; Dallos, Jairo A Guerrero

    2011-01-15

    A dynamic model for uptake of pesticides in potatoes is presented and evaluated with measurements performed within a field trial in the region of Boyacá, Colombia. The model takes into account the time between pesticide applications and harvest, the time between harvest and consumption, the amount of spray deposition on soil surface, mobility and degradation of pesticide in soil, diffusive uptake and persistence due to crop growth and metabolism in plant material, and loss due to food processing. Food processing steps included were cleaning, washing, storing, and cooking. Pesticide concentrations were measured periodically in soil and potato samples from the beginning of tuber formation until harvest. The model was able to predict the magnitude and temporal profile of the experimentally derived pesticide concentrations well, with all measurements falling within the 90% confidence interval. The fraction of chlorpyrifos applied on the field during plant cultivation that eventually is ingested by the consumer is on average 10(-4)-10(-7), depending on the time between pesticide application and ingestion and the processing step considered.

  7. Larvas output and influence of human factor in reliability of meat inspection by the method of artificial digestion

    OpenAIRE

    Đorđević Vesna; Savić Marko; Vasilev Saša; Đorđević Milovan

    2013-01-01

    On the basis of the performed analyses of the factors that contributed the infected meat reach food chain, we have found out that the infection occurred after consuming the meat inspected by the method of collective samples artificial digestion by using a magnetic stirrer (MM). In this work there are presented assay results which show how modifications of the method, on the level of final sedimentation, influence the reliability of Trichinella larvas detect...

  8. 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.

  9. 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.

  10. 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.

  11. Uptake, translocation, and toxicity of gold nanorods in maize

    Science.gov (United States)

    Moradi Shahmansouri, Nastaran

    Nanomaterials are widely used in many different products, such as electronics, cosmetics, industrial goods, biomedical uses, and other material applications. The heavy emission of nanomaterials into the environment has motived increasing concern regarding the effects on ecosystems, food chains, and, human health. Plants can tolerate a certain amount of natural nanomaterials, but large amounts of ENMs released from a variety of industries could be toxic to plants and possibly threaten the ecosystem. Employing phytoremediation as a contamination treatment method may show promise. However a pre-requisite to successful treatment is a better understanding of the behavior and effects of nanomaterials within plant systems. This study is designed to investigate the uptake, translocation, bioavailability, and toxicity of gold nanorods in maize plants. Maize is an important food and feed crop that can be used to understand the potential hazardous effects of nanoparticle uptake and distribution in the food chain. The findings could be an important contribution to the fields of phytoremediation, agri-nanotechnology, and nanoparticle toxicity on plants. In the first experiment, hydroponically grown maize seedlings were exposed to similar doses of commercial non-coated gold nanorods in three sizes, 10x34 nm, 20x75 nm, and 40x96 nm. The three nanorod species were suspended in solutions at concentrations of 350 mg/l, 5.8 mg/l, and 14 mg/l, respectively. Maize plants were exposed to all three solutions resulting in considerably lower transpiration and wet biomass than control plants. Likewise, dry biomass was reduced, but the effect is less pronounced than that of transpiration and wet biomass. The reduced transpiration and water content, which eventually proved fatal to exposed plants, were most likely a result of toxic effect of gold nanorod, which appeared to physically hinder the root system. TEM images proved that maize plants can uptake gold particles and accumulate them in

  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. Habitat selection by chironomid larvae: fast growth requires fast food.

    NARCIS (Netherlands)

    de Haas, E.M.; Wagner, C.; Koelmans, A.A.; Kraak, M.H.S.; Admiraal, W.

    2006-01-01

    1. Sediments have been considered as a habitat, a cover from predators and a source of food, but also as a source of potential toxic compounds. Therefore, the choice of a suitable substrate is essential for the development of chironomids. 2. For the midge Chironomus riparius (Meigen 1804) the growth

  16. 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)

  17. Implications for food safety of the uptake by tomato of 25 trace-elements from a phosphogypsum amended soil from SW Spain

    International Nuclear Information System (INIS)

    Enamorado, Santiago; Abril, José M.; Delgado, Antonio; Más, José L.; Polvillo, Oliva; Quintero, José M.

    2014-01-01

    Highlights: • Uptake of 25 trace-elements by tomato was studied in phosphogypsum-amended soils. • Cadmium had high transfer factors in tomato shoots (4.0) and fruits (1.5). • These two TF values of Cd increased to 5.7 and 2.5 after PG-inputs, respectively. • PG decreased the concentration of B, Cu, Sb, Cs, Ba, Tl and Th in fruits. • Assessment on trace elements in PG is needed to avoid exceeding legal limits in food. -- Abstract: Phosphogypsum (PG) has been usually applied as Ca-amendment to reclaim sodic soils such as those in the marshland area of Lebrija (SW Spain). This work aimed at the effects of PG amendments on the uptake of trace-elements by tomato and its implications for food safety. A completely randomized experiment was performed using a representative soil from Lebrija in a greenhouse involving six replicates and four PG treatments equivalent to 0, 20, 60, and 200 Mg ha −1 . Soil-to-plant transfer factors (TFs) were determined for Be, B, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, Pb, Th and U. The highest TF in shoots was observed for Cd (4.0; 1.5 in fruits), its concentration being increased with increasing PG doses due to its content in this metal (2.1 mg Cd kg −1 PG). Phosphogypsum applying decreased the concentrations of Mn, Co and Cu in shoots; and of B, Cu, Sb, Cs, Ba, Tl and Th in fruits, however enhanced the accumulation of Se in fruits. Although Cd concentrations in tomato were below the maximum allowed levels in control pots (0 Mg PG ha −1 ), PG amendments above 60 Mg ha −1 exceeded such limits

  18. Implications for food safety of the uptake by tomato of 25 trace-elements from a phosphogypsum amended soil from SW Spain

    Energy Technology Data Exchange (ETDEWEB)

    Enamorado, Santiago [Departamento de Física Aplicada I, Universidad de Sevilla, EPS, c/Virgen de África n° 7, D.P. 41011, Seville (Spain); Abril, José M., E-mail: jmabril@us.es [Departamento de Física Aplicada I, Universidad de Sevilla, EPS, c/Virgen de África n° 7, D.P. 41011, Seville (Spain); Delgado, Antonio [Departamento de Ciencias Agroforestales, Universidad de Sevilla, ETSIA, Ctra. Utrera km. 1, D.P. 41013, Seville (Spain); Más, José L. [Departamento de Física Aplicada I, Universidad de Sevilla, EPS, c/Virgen de África n° 7, D.P. 41011, Seville (Spain); Polvillo, Oliva [Agricultural Research Service of the University of Seville (SIA-CITIUS), Ctra. Utrera Km. 1, D.P. 41013, Seville (Spain); Quintero, José M. [Departamento de Ciencias Agroforestales, Universidad de Sevilla, ETSIA, Ctra. Utrera km. 1, D.P. 41013, Seville (Spain)

    2014-02-15

    Highlights: • Uptake of 25 trace-elements by tomato was studied in phosphogypsum-amended soils. • Cadmium had high transfer factors in tomato shoots (4.0) and fruits (1.5). • These two TF values of Cd increased to 5.7 and 2.5 after PG-inputs, respectively. • PG decreased the concentration of B, Cu, Sb, Cs, Ba, Tl and Th in fruits. • Assessment on trace elements in PG is needed to avoid exceeding legal limits in food. -- Abstract: Phosphogypsum (PG) has been usually applied as Ca-amendment to reclaim sodic soils such as those in the marshland area of Lebrija (SW Spain). This work aimed at the effects of PG amendments on the uptake of trace-elements by tomato and its implications for food safety. A completely randomized experiment was performed using a representative soil from Lebrija in a greenhouse involving six replicates and four PG treatments equivalent to 0, 20, 60, and 200 Mg ha{sup −1}. Soil-to-plant transfer factors (TFs) were determined for Be, B, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, Pb, Th and U. The highest TF in shoots was observed for Cd (4.0; 1.5 in fruits), its concentration being increased with increasing PG doses due to its content in this metal (2.1 mg Cd kg{sup −1} PG). Phosphogypsum applying decreased the concentrations of Mn, Co and Cu in shoots; and of B, Cu, Sb, Cs, Ba, Tl and Th in fruits, however enhanced the accumulation of Se in fruits. Although Cd concentrations in tomato were below the maximum allowed levels in control pots (0 Mg PG ha{sup −1}), PG amendments above 60 Mg ha{sup −1} exceeded such limits.

  19. ANALISIS COMPOSICIONAL, MICROBIOLÓGICO Y DIGESTIBILIDAD DE LA PROTEÍNA DE LA HARINA DE LARVAS DE Hermetia illuscens L (DIPTERA:STRATIOMYIIDAE EN ANGELÓPOLIS-ANTIOQUIA, COLOMBIA COMPOSITIONAL, MICROBIOLOGICAL AND PROTEIN DIGESTIBILITY ANALYSIS OF THE LARVA MEAL OF Hermetia illuscens L. (Diptera:Stratiomyiidae AT ANGELÓPOLIS - ANTIOQUIA, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Gloria Patricia Arango Gutiérrez

    2004-12-01

    Full Text Available Se estudió el valor nutritivo de la harina de las larvas de Hermetia illuscens L. a partir del análisis composicional, prueba de digestibilidad y calidad microbiológica de esta, comparada con una materia prima convencional como la harina de pescado y con otro díptero como es la Musca domestica L. ya que comparten hábitat y ha sido estudiado como materia prima. La harina de las larvas de la mosca negra soldado, por su análisis proximal puede ser considerada un ingrediente proteico. Además presenta una alta digestibilidad. Las características bromatol��gicas asociadas a su calidad microbiológica la convierte en una materia prima promisoria en la alimentación animal.The nutritional value of the larva meal of Hermetia illuscens L. was investigated by means of compositional analysis, digestability tests and its microbiological quality, as compared to other conventional feeds such as fish meal and other Diptera such as Musca domestica L., given that they share the same habitat and have been studied as a food source. The meal of the soldier fly larva could be considered a proteinic ingredient based on its nutritional composition. Also, it had high digestibility. The bromatological characteristics associated with its microbiological quality makes it a promising feed for animal nutrition.

  20. Improving food security and nutrition through research | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Informing policy through agriculture and food security research. Improving the uptake of agricultural and food security research into policy and practice is a central objective of IDRC's Agriculture and Food Security program. To maximize the impact of proven solutions, the program set out to inform and engage both Canadian ...

  1. Biological activity of Ruta chalepensis (Rutaceae and Sechium pittieri (Cucurbitaceae extracts on Hypsipyla grandella (Lepidoptera: Pyralidae larvae

    Directory of Open Access Journals (Sweden)

    Fernando Mancebo

    2001-06-01

    Full Text Available Biological activity of a plant extract (common rue, Ruta chalepensis and a semi purifíed fraction (from "tacaco cimarrón", Sechium pittieri on mahogany shootborer larvas (Hypsipyla grandella was studied. A randomized complete block design, with four replications, was used. H. grandella third instar larvas were exposed for 24 h to Cedrela odorata leaf discs dipped in several treatment dissolutions of each extract (0.1, 0.32, 1.0, 3.20, and 10%; afterwards, each larva was transferred to a flask containing an artificial diet and was allowed to complete its development. Variables measured included food consumption (foliar area eaten in 24 h, mortality, and developmental effects (developmental time for each larval instar and the pupa, and pupal weight. The common rue extract showed a clear antifeedant activity at a concentration as low as 0.32%, whereas the "tacaco cimarrón" fraction caused toxicity, especially at the two highest concentrations (3.20 and 10%.Se estudió la actividad biológica de un extracto de follaje de ruda (Ruta chalepensis y de una fracción semipurificada de "tacaco cimarrón" (Sechium pittieri sobre las larvas del gusano barrenador de las meliáceas (Hypsipyla grandella. Se utilizó un diseño de bloques completos al azar, con cuatro repeticiones. Durante 24 h se expusieron larvas de tercer estadio de H. grandella a discos de follaje de Cedrela odorata impregnados con cada tratamiento. Estos consistieron en disoluciones de cada extracto (0.1, 0.32, 1.0, 3.20 y 10%; posteriormente cada larva se transfirió a un frasco que contenía dieta artificial, donde se le permitió completar su desarrollo. Las variables de respuesta fueron el consumo de alimento (área foliar comida en 24 h, la mortalidad y efectos sobre el desarrollo (tiempo de desarrollo de cada estadio larval y de la pupa, y el peso de la pupa. El extracto de ruda causó fagodisuasión a una concentración de apenas 0.32%, mientras que la fracción de "tacaco cimarr

  2. Application of Pb isotopes to track the sources and routes of metal uptake in the earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    Bader Albogami

    2014-12-01

    Full Text Available The aim of this work is to determine the important routes of metal uptake in earthworms to enable a better understanding of the primary source of metal uptake in the environment. Earthworms can take up chemicals from pore water and soil both by ingestion and through contact with their skin. However, it is unclear which pathway is the most important for metal uptake. An experiment was designed in which both soil chemistry and foods were artificially manipulated, producing different pools of soil lead (Pb with different isotope compositions at a range of Pb concentrations. Earthworms (Eiseniafetida were exposed to different lead concentrations through the addition of 500 mg/kg lead oxide (Pb3O4 to soil and 500 mg/kg lead nitrate to food (manure, with distinctly different isotopic compositions. Earthworms were also exposed to combinations of soil only and soil plus food in order to quantify the proportions of Pb taken up from each component. After acid digestion of the earthworm tissues, the Pb isotope composition of the accumulated lead in the earthworms was measured using a Thermo-fisher, iCAPQ, ICP-MS for 208Pb/206Pb and 207Pb/206Pb ratios measured relative to NIST SRM 981, allowing us to determine the pathway of lead uptake. Mixing calculations have been used to deconvolute the lead isotope signatures and identify the amount of lead taken up by the earthworms from the different soil pools. Differences in bioaccumulation factors and the relative amounts of lead accumulated from different pools changes as a function of concentration in the different pools. Earthworms were shown to uptake lead from bothsoil and food sources through ingestion route. Our findings suggest that a major pathway of lead uptake in earthworm species is heavily influenced by their ecology.

  3. Free Amino Acid Enriched Rotifer for Larval Grouper Cromileptes altivelis (Pengkayaan Rotifer dengan Asam Amino Bebas Untuk Larva Kerapu Bebek Cromileptes altivelis

    Directory of Open Access Journals (Sweden)

    Dedi Jusadi

    2015-12-01

    , taurin lebih baik dibanding glutamin karena memberi efek ke pertumbuhan ikan yang lebih cepat. Kata kunci: taurin, glutamin, kerapu bebek, Cromileptes altivelis. The hatchery production of grouper faced to the problem of low surival rate, especially during the first feeding period. During this period, the digestive organ of larvae was underdeveloped, and the nutrient in live food was not readily absorbed by larvae. Feeding on free amino acids, such as taurine or glutamine, enriched rotifer would be enhanced the nutrient readily absorbed thereby resulting to the improvement of growth and survival rate of larvae. A duplicate experiment was conducted to evaluate the effect of rotifer enriched with free amino acid of glutamine or taurine, on the growth and survival rate of larval grouper Cromileptes altivelis. One day old larvae were cultured in 500 l fiberglass containing 330 l of sea water with a density of 10 ind.L-1. Larvae were fed on rotifer enriched with either 0.5 g glutamine, 0.5 g taurine, or without glutamine nor taurine. Larvae were fed on rotifer twice a day at 08.00 and 14.00, and cultured for 16 days. One h after feeding, rotifer content in the gut of larvae were observed. Results showed that larvae fed on rotifer enriched with 0.5 g taurine or 0.5 g glutamie had higher rotifer content in the gut than that in the other group. Larvae fed on rotifer enriched with 0.5 g glutamine or 0.5 g taurine had the same survival rate (P>0.05, 19.2±2.25% and 24.5±1.20%, respectively; these values were significantly higher than that in the other group which was 13.0±1.70%.  The total length of larvae fed on rotifer enriched with 0.5 g taurine (5.5±0.18 mm significantly was the biggest compared than others; while those fed on rotifer enriched with 0.5 g glutamine (5.3±0.12 mm was bigger than fish fed on rotifer without glutamine nor taurine (5.0±0.16 mm. Thus, it can be concluded that survival rate and growth of larvae were improved when feeding on rotifer enriched with

  4. 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

  5. Review of Black Soldier Fly (Hermetia illucens) as Animal Feed and Human Food.

    Science.gov (United States)

    Wang, Yu-Shiang; Shelomi, Matan

    2017-10-18

    Food futurists accept that sustainability-minded humanity will increasingly incorporate insects as alternative protein. The most studied and easily reared species are not necessarily the most sustainable, acceptable, or delicious. Here, we review the literature on the black soldier fly, Hermetia illucens, which is capable of efficiently converting a wide variety of organic materials, from food waste to manure, into insect biomass. They can be grown and harvested without dedicated facilities and are not pestiferous. Their larvae are 42% crude protein and 29% fat, although they are higher in saturated fats than most insects. They do not concentrate pesticides or mycotoxins. They are already grown and recommended for use as animal feed, but with regional legal restrictions on how this is done. For commercial use in human foods, larvae could potentially be milled and converted into a textured protein with a strong flavor. Their biggest advantage over other insects is their ability to convert waste into food, generating value and closing nutrient loops as they reduce pollution and costs. This general advantage is also their greatest disadvantage, for the social stigmas and legal prohibitions against eating organisms that eat waste are added to extant taboos facing insect consumption.

  6. 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

  7. Uptake of Hg2+ by picocyanobacteria in natural water from four Andean lakes

    Directory of Open Access Journals (Sweden)

    Diéguez M.C.

    2014-07-01

    Full Text Available In lake food webs, planktonic bacteria and algae represent the greatest bioconcentration step for Hg2+ and monomethyl-Hg (MeHg. As they are the most abundant organisms in planktonic trophic webs and also the main food resource for herbivorous plankton, they can mobilize large amounts of Hg to higher trophic levels. In Andean Patagonian lakes (Argentina, dissolved organic matter (DOM concentration and character, coupled with photo-reactions, play a central role in the complexation of Hg2+ in the water column and can even regulate the uptake of Hg2+ by planktonic algae. In this investigation we evaluated the DOM character of natural waters (NW from four Andean lakes and studied its influence on the uptake of 197Hg2+ in a strain of the picocyanobacteria Synechococcus by using Hg2+ labeled with 197Hg2+. The uptake of radiolabeled Hg2+ by Synechococcus showed different magnitude in NW of lakes Moreno, El Trébol, Morenito and Escondido. Increasing lake DOM concentration reduced the bioavailability of Hg2+ as indicated by the lower uptakes rates found in NW with higher complexity and concentration of the DOM pool. Uptakes of Hg2+ by this picocyanobacteria contrasted among NW from pelagic (surface and bottom and littoral compartments of Lake Escondido which suggest that the entry of this metal may be highly variable even in the same environment. The study of the uptake of radiolabeled Hg2+ in a set of dilutions of NW from Lake Escondido demonstrated that the bioavailability of Hg2+ decrease with increasing DOM concentration.

  8. The B vitamins nicotinamide (B3) and riboflavin (B2) stimulate metamorphosis in larvae of the deposit-feeding polychaete Capitella teleta: implications for a sensory ligand-gated ion channel.

    Science.gov (United States)

    Burns, Robert T; Pechenik, Jan A; Biggers, William J; Scavo, Gia; Lehman, Christopher

    2014-01-01

    Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1-2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae.

  9. The B Vitamins Nicotinamide (B3) and Riboflavin (B2) Stimulate Metamorphosis in Larvae of the Deposit-Feeding Polychaete Capitella teleta: Implications for a Sensory Ligand-Gated Ion Channel

    Science.gov (United States)

    Burns, Robert T.; Pechenik, Jan A.; Biggers, William J.; Scavo, Gia; Lehman, Christopher

    2014-01-01

    Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1–2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae. PMID:25390040

  10. 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...

  11. 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.

  12. In vitro digestibility and fermentability of selected insects for dog foods

    NARCIS (Netherlands)

    Bosch, Guido; Vervoort, J. J M; Hendriks, W. H.

    2016-01-01

    Insects are considered as a sustainable protein source for future pet foods. Here we aimed to evaluate the protein quality of larvae of the black soldier fly (Hermetia illucens, BSF), housefly (Musca domestica, HF) and yellow mealworm (Tenebrio molitor, YMW) and to evaluate the fermentation

  13. 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.

  14. Plant uptake of pentachlorophenol from sludge-amended soils

    International Nuclear Information System (INIS)

    Bellin, C.A.; O'Connor, G.A.

    1990-01-01

    A greenhouse study was conducted to determine the effects of sludge on plant uptake of 14 C-pentachlorophenol (PCP). Plants included tall fescue (Festuca arundinacea Schreb.), lettuce (Latuca sativa L.), carrot (Daucus carota L.), and chile pepper (Capsicum annum L.). Minimal intact PCP was detected in the fescue and lettuce by gas chromatography/mass spectrometry (GC/MS) analysis. No intact PCP was detected in the carrot tissue extracts. Chile pepper was not analyzed for intact PCP because methylene chloride extracts contained minimal 14 C. The GC/MS analysis of soil extracts at harvest suggests a half-life of PCP of about 10 d independent of sludge rate or PCP loading rate. Rapid degradation of PCP in the soil apparently limited PCP availability to the plant. Bioconcentration factors (dry plant wt./initial soil PCP concentration) based on intact PCP were < 0.01 for all crops, suggesting little PCP uptake. Thus, food-chain crop PCP uptake in these alkaline soils should not limit land application of sludge

  15. Progress in food irradiation: Australia

    Energy Technology Data Exchange (ETDEWEB)

    Wills, P A

    1982-11-01

    Progress in food irradiation treatment of Australian commodities, such as meat, pepper, honey, fruit is described. Irradiation took place with /sup 60/Co gamma radiation while testing for radiation sensitivity of Staphyllococcus in meat, of Bacillus aureus in pepper, of Streptococcus plutin and Bacillus larvae in honey, and of the fruitfly Dacus tryoni infesting fruit. So far, two State Health Commissions in Australia have authorised irradiation of shrimps with their sale being restricted to the State authorising treatment.

  16. Progress in food irradiation: Australia

    International Nuclear Information System (INIS)

    Wills, P.A.

    1982-01-01

    Progress in food irradiation treatment of Australian commodities, such as meat, pepper, honey, fruit is described. Irradiation took place with 60 Co gamma radiation while testing for radiation sensitivity of Staphyllococcus in meat, of Bacillus aureus in pepper, of Streptococcus plutin and Bacillus larvae in honey, and of the fruitfly Dacus tryoni infesting fruit. Sofar, two State Health Commissions in Australia have authorised irradiation of shrimps with their sale being restricted to the State authorising treatment. (AJ) [de

  17. Uptake of allochthonous dissolved organic matter from soil and salmon in coastal temperate rainforest streams

    Science.gov (United States)

    Jason B. Fellman; Eran Hood; Richard T. Edwards; Jeremy B. Jones

    2009-01-01

    Dissolved organic matter (DOM) is an important component of aquatic food webs. We compare the uptake kinetics for NH4-N and different fractions of DOM during soil and salmon leachate additions by evaluating the uptake of organic forms of carbon (DOC) and nitrogen (DON), and proteinaceous DOM, as measured by parallel factor (PARAFAC) modeling of...

  18. 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.

  19. Performance of Helicoverpa armigera (Hübner (Lepidoptera: Noctuidae larvae in different food sources

    Directory of Open Access Journals (Sweden)

    Crislaine Sartori Suzana

    2015-12-01

    Full Text Available Recently observed in Brazil, Helicoverpa armigera became a relevant pest due to its rapid spread and the economic importance of crops in which it has established, such as soybean and maize. Understanding its establishment process in different regions and production systems, as well as the population dynamics of a polyphagous pest, as the basis for its management, depends on the knowledge of the effect of plant species as food sources on the pest biology. A laboratory experiment was conducted, supplying the caterpillars with reproductive organs of soybean, maize, canola, black oat, oat, turnip and ryegrass. It was concluded that the different food sources affect the larval development of H. armigera. Maize and wheat ears and canola siliques are the best food sources for the development of H. armigera. Ryegrass ears, on the other hand, are the worst ones. Black oat and oat panicles and turnip siliques are less suitable than soybean pods as food sources for the caterpillars.

  20. Subcellular partitioning of cadmium and zinc in mealworm beetle (Tenebrio molitor) larvae exposed to metal-contaminated flour.

    Science.gov (United States)

    Bednarska, Agnieszka J; Świątek, Zuzanna

    2016-11-01

    By studying the internal compartmentalization of metals in different subcellular fractions we are able to better understand the mechanisms of metal accumulation in organisms and the transfer of metals through trophic chains. We investigated the internal compartmentalization of cadmium (Cd) and zinc (Zn) in mealworm beetle (Tenebrio molitor) larvae by breeding them in flour contaminated with either Cd at 100, 300 and 600mgkg(-1), or Zn at 1000 and 2000mgkg(-1). We separated the cellular components of the larvae into 3 fractions: the S1 or cytosolic fraction containing organelles, heat-sensitive and heat-stable proteins, the S2 or cellular debris fraction and the G or metal-rich granule fraction. The concentration of Cd and Zn in each fraction was measured at 0, 7, 14 and 21 days of being fed the flour. The concentration of Cd in the flour affected the concentration of Cd measured in each larval subcellular fraction (p≤0.0001), while the concentration of Zn in the flour only affected the Zn concentration in the S2 and G fractions (p≤0.02). Both Cd and Zn concentrations in mealworms remained relatively constant during the exposure (days 7, 14 and 21) in all three fractions, but the Cd concentrations were much higher than those found in larvae before the exposure (day 0). The concentration of Cd in the flour, however, did not affect the percentage of Cd in the S1 fraction. The contribution of Cd in the G fraction to the total Cd amount was similar (30-40%) in all Cd treatments. The percentage of Zn in all three fractions was not affected by the concentration of Zn in the flour and the relative contributions of each subcellular fraction to the total burden of Zn remained generally constant for both control and treated larvae. In general, larvae sequestered approximately 30% of Cd and Zn in the S1 fraction, which is important for the transport of metals to higher trophic levels in a food web. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. 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

  2. Alternative supplementary biochemic food for growing up the fresh water lobster (Cherax quadricarinatus

    Directory of Open Access Journals (Sweden)

    PRABANG SETYONO

    2009-11-01

    Full Text Available Priyono E, Astirin OP, Setyono P. 2009. Alternative supplementary biochemic food for growing up the fresh water lobster (Cherax quadricarinatus. Nusantara Bioscience 1: 123-130. This research denotes to know the influence of biochemic composition to the rapid grow of fresh water lobster on the stadium of post larva (PL of 60 within three months. This research used the complete random planning dealing with 4 treatments and each treatment would get 3 times cycle. The treatments cover, group K tested animal was treted with 100% mill food containing 30% of protein. Group A is given with food and biochemic food containing 13,34% of protein. Group B is the treated with mill food which is mixed with biochemic food containing 10,7% of protein. While group C was tested by treating them with mill food and biochemic food containing 13,58%. After all the above mentioned would be set up within 3:1 comparation. The variable of this research were the length of the abdomen, cephalothorax, total length, and the wet weight. The data analysis is using ANOVA system on 95% power test completed by of SPSS version 13. The result of the research shows that mentioned treatments give us the same influence toward the growth of fresh water lobster. The composition of biochemic food with the containing protein around 10,7%,13.34% and 13,38% has given the same effect to the lobster growth on post larva 60 level. There is strong correlation between abdomen and cephalothorax and between the total length and the lobsters weight.Key words: Cherax quadricarinatus, suplementary food, water quality.Abstrak. Priyono E, Astirin OP, Setyono P. 2009. Alternatif penambahan suplemen hayati untuk meningkatkan pertumbuhan udang lobster air tawar (Cherax quadricarinatus. Nusantara Bioscience 1: 123-130. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian suplemen hayati sehingga dapat meningkatkan pertumbuhan lobster air tawar pada stadia post larva (PL 60 pada masa pertumbuhan 3

  3. Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae, a predator of container breeding mosquitoes

    Directory of Open Access Journals (Sweden)

    D Dominic Amalraj

    2005-12-01

    Full Text Available Food utilization by the larvae of Toxorhynchites splendens (Wiedemann was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston, and Culex quinquefasciatus (Say. Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id and food availability were higher when offered early instars of prey (first and second instars than late instars. Consumption rate (Cr of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

  4. 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)

  5. 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)

  6. Natural copepods are superior to enriched artemia nauplii as feed for halibut larvae (Hippoglossus hippoglossus) in terms of survival, pigmentation and retinal morphology: relation to dietary essential fatty acids.

    Science.gov (United States)

    Shields, R J; Bell, J G; Luizi, F S; Gara, B; Bromage, N R; Sargent, J R

    1999-06-01

    enriched Artemia as food for halibut larvae in terms of survival, eye development and pigmentation, and this superiority can be related to the level of DHA in the feed.

  7. In vitro digestibility and fermentability of selected insects for dog foods

    NARCIS (Netherlands)

    Bosch, G.; Vervoort, J.J.M.; Hendriks, W.H.

    2016-01-01

    Insects are considered as a sustainable protein source for future pet foods. Here we aimed to evaluate the protein quality of larvae of the black soldier fly (Hermetia illucens, BSF), housefly (Musca domestica, HF) and yellow mealworm (Tenebrio molitor, YMW) and to evaluate the fermentation

  8. 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

  9. 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

  10. 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.

  11. Effect of water management and silicon on germination, growth, phosphorus and arsenic uptake in rice.

    Science.gov (United States)

    Zia, Zahida; Bakhat, Hafiz Faiq; Saqib, Zulfiqar Ahmad; Shah, Ghulam Mustafa; Fahad, Shah; Ashraf, Muhammad Rizwan; Hammad, Hafiz Mohkum; Naseem, Wajid; Shahid, Muhammad

    2017-10-01

    Silicon (Si) is the 2nd most abundant element in soil which is known to enhance stress tolerance in wide variety of crops. Arsenic (As), a toxic metalloid enters into the human food chain through contaminated water and food or feed. To alleviate the deleterious effect of As on human health, it is a need of time to find out an effective strategy to reduce the As accumulation in the food chain. The experiments were conducted during September-December 2014, and 2016 to optimize Si concentration for rice (Oryza sativa L.) exposed to As stress. Further experiment were carried out to evaluate the effect of optimum Si on rice seed germination, seedling growth, phosphorus and As uptake in rice plant. During laboratory experiment, rice seeds were exposed to 150 and 300µM As with and without 3mM Si supplementation. Results revealed that As application, decreased the germination up to 40-50% as compared to control treatment. Arsenic stress also significantly (P management, significantly (P˂0.05) affected the plant growth, Si and As concentrations in the plant. Arsenic uptake was relatively less under aerobic conditions. The maximum As concentration (9.34 and 27.70mgkg DW -1 in shoot and root, respectively) was found in plant treated with 300µM As in absence of Si under anaerobic condition. Similarly, anaerobic condition resulted in higher As uptake in the plants. The study demonstrated that aerobic cultivation is suitable to decrease the As uptake and in rice exogenous Si supply is beneficial to decrease As uptake under both anaerobic and aerobic conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Infectivity of Oryctes Nudivirus Produced on Cell Culture Dsir Ha-1179 Against Larvae and Its Effects on Feeding of Neonates of Rhinoceros Beetle, Oryctes Rhinoceros

    International Nuclear Information System (INIS)

    Nur Ain Farhah Ros Saidon Khudri; Wahizatul Afzan Azmi; Ramle Moslim; Norman Kamarudin; Siti Ramlah Ahmad Ali

    2016-01-01

    The Oryctes nudivirus (OrNV) is a classical biocontrol agent for a major oil palm insect pest the rhinoceros beetle, Oryctes rhinoceros. The infectivity of three Malaysian indigenous types of OrNV types A, B and C were tested on larvae and neonates. On larvae, the peroral inoculation test technique indicated that the highest mortality of 100 % was achieved using type A produced from cell culture DSIR-HA-1179, while the highest infectivity of 41.7 % was recorded for type A prepared from infected guts. No differences in infectivity were observed on other treatments, which ranged from 13.1 % to 41.7 %. In the substrate contamination inoculation test technique, results showed that the level of infectivity was even lower in all OrNV treatments, ranging as low as 6.7 % to only 15.0 %. Low infectivity was mainly due to inactivation of virus inocula in the larval food substrates. Based on the results for both inoculation methods, the OrNV type C prepared from cell culture DSIR-HA-1179 was found more effective in controlling the L3 larvae than the other types of OrNV. The impact of OrNV infection on food consumption by the neonates was studied. The feeding of inoculated neonates with OrNV reduced rapidly, especially at the early stage of the experiment between eight days after treatment (DAT) to 16 DAT. At this period, the food consumption by all tested OrNV was rapidly reduced and maintained low until the experiment ended at 60 DAT. The highest feeding reduction rate was on neonates treated by type A (-0.074x) followed by neonates treated by type C (-0.053x) and type B (-0.035x). Therefore, it was suggested that besides on highly virulent, the selection of OrNV for field release should also based on high reduction rate on food consumption by the infected insects on plant hosts. (author)

  13. 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.

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. Role of biogenic amines in the post-mortem migration of Anisakis pegreffii (Nematoda: Anisakidae Dujardin, 1845) larvae into fish fillets.

    Science.gov (United States)

    Šimat, Vida; Miletić, Jelena; Bogdanović, Tanja; Poljak, Vedran; Mladineo, Ivona

    2015-12-02

    Infective third-stage larvae (L3) of nematode Anisakis spp. have been recognized as one of the major food-borne threats in lightly processed fish products in Europe, particularly in the Mediterranean region. Therefore, the effect of different storage temperatures of fish on larval post-mortem migration from visceral cavity into fillets is an important parameter to take into account when evaluating the risk for consumer safety. The European anchovy (Engraulis encrasicolus) were caught during fishing season, a subsample of fillets was checked for the presence of Anisakis larvae at capture (mean abundance=0.07), and the rest was stored at four different temperatures (-18, 0, 4 and 22°C) in order to count migrating larvae and measure the production of biogenic amines over a period of time. Larvae were identified by morphological features and molecular tools. Post-mortem migration was observed in fillets stored at 0 and 4°C after three and five days, respectively, but not at 22 and -18°C. In case of storage at 22°C for two days, at the onset of putrefaction of the visceral organs, larvae migrated out of the visceral cavity towards the fish surface. Measured pH and biogenic amine profile during storage indicated that certain biochemical conditions trigger larval migration into fillets. Likewise, migration was observed at pH ~6.4 when sensory degradation of the fish was markedly visible. Although larval migration was delayed for approximately four days at a temperature of fillet was high and statistically significant at both 0 (r=0.998, p<0.01) and 4°C (r=0.946, p<0.05). Out of eight biogenic amines measured, cadaverine and putrescine levels correlated the most with the post-mortem migration at 4°C, while tyramine levels were significant at both temperatures. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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

  1. 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.

  2. 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.

  3. Effect of an insect juvenile hormone analogue, Fenoxycarb on development and oxygen uptake by larval lobsters Homarus gammarus (L.).

    Science.gov (United States)

    Arnold, Katie E; Wells, Colin; Spicer, John I

    2009-04-01

    Little attention has been focused on the effect of anthropogenic compounds that disrupt the endocrine systems in crustaceans. Consequently, this study investigated the effects of the juvenile hormone analogue (JHA), Fenoxycarb on selected physiological and developmental processes of the zoeal stages in the European lobster, Homarus gammarus. Chronic exposure to Fenoxycarb (50microg L(-1)) resulted in a significant (p < 0.05) reduction in moult frequency and size at moult. Fenoxycarb exposure extended zoeal duration between zoea I to II (p<0.05) and resulted in total inhibition of the moult from zoea II to III. Significantly greater rates of O2 uptake were observed in Fenoxycarb-exposed larvae in comparison with controls (p<0.05). All rates of O2 uptake decreased significantly between 7 and 12d of exposure (p<0.05). At 12d, exposure to the solvent control no longer influenced rates of O2 uptake, but it was not possible to attribute increased O2 uptake to Fenoxycarb exposure directly, as treated individuals did not moult beyond zoea III. The low exposure concentrations of Fenoxycarb, comparable to those used in plant protection, resulted in endocrine disrupted responses in H. gammarus (albeit with little clear, demonstrable effect on metabolism) a finding that could have important ecological and commercial implications.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm)

    OpenAIRE

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju; Moon, Kyoung-Sik

    2014-01-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration tes...

  6. 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.

  7. 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)

  8. Comparative Study on Quality Parameters of Royal Jelly, Apilarnil and Queen Bee Larvae Triturate

    Directory of Open Access Journals (Sweden)

    Rodica MARGAOAN

    2017-05-01

    Full Text Available Given their beneficial effects in terms of health, the natural products, especially beehive products, have drawn the attention of consumers since long time ago. In order to guarantee the quality of these products on the market, their chemical composition needs to be analyzed. Thus, this current research had as objective the establishment of quality parameters for beehive brood food derived products: apilarnil and queen bee larvae triturate. These two products were compared with royal jelly which is the basis of brood food in the first 3 days of larval stage. The carbohydrates were determined by HPLC-IR and allowed the identification of seven carbohydrate compounds, predominantly glucose, fructose and sucrose. The lipid profile was analyzed by the Soxhlet method. The total protein content was determined by the Kjeldahl method. Free amino acids were analyzed by LC-MS. A total of 31 amino acids were identified of which nine are essential amino acids for humans.Â

  9. 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.

  10. Determining the diet of larvae of western rock lobster (Panulirus cygnus using high-throughput DNA sequencing techniques.

    Directory of Open Access Journals (Sweden)

    Richard O'Rorke

    Full Text Available The Western Australian rock lobster fishery has been both a highly productive and sustainable fishery. However, a recent dramatic and unexplained decline in post-larval recruitment threatens this sustainability. Our lack of knowledge of key processes in lobster larval ecology, such as their position in the food web, limits our ability to determine what underpins this decline. The present study uses a high-throughput amplicon sequencing approach on DNA obtained from the hepatopancreas of larvae to discover significant prey items. Two short regions of the 18S rRNA gene were amplified under the presence of lobster specific PNA to prevent lobster amplification and to improve prey amplification. In the resulting sequences either little prey was recovered, indicating that the larval gut was empty, or there was a high number of reads originating from multiple zooplankton taxa. The most abundant reads included colonial Radiolaria, Thaliacea, Actinopterygii, Hydrozoa and Sagittoidea, which supports the hypothesis that the larvae feed on multiple groups of mostly transparent gelatinous zooplankton. This hypothesis has prevailed as it has been tentatively inferred from the physiology of larvae, captive feeding trials and co-occurrence in situ. However, these prey have not been observed in the larval gut as traditional microscopic techniques cannot discern between transparent and gelatinous prey items in the gut. High-throughput amplicon sequencing of gut DNA has enabled us to classify these otherwise undetectable prey. The dominance of the colonial radiolarians among the gut contents is intriguing in that this group has been historically difficult to quantify in the water column, which may explain why they have not been connected to larval diet previously. Our results indicate that a PCR based technique is a very successful approach to identify the most abundant taxa in the natural diet of lobster larvae.

  11. Review of Black Soldier Fly (Hermetia illucens as Animal Feed and Human Food

    Directory of Open Access Journals (Sweden)

    Yu-Shiang Wang

    2017-10-01

    Full Text Available Food futurists accept that sustainability-minded humanity will increasingly incorporate insects as alternative protein. The most studied and easily reared species are not necessarily the most sustainable, acceptable, or delicious. Here, we review the literature on the black soldier fly, Hermetia illucens, which is capable of efficiently converting a wide variety of organic materials, from food waste to manure, into insect biomass. They can be grown and harvested without dedicated facilities and are not pestiferous. Their larvae are 42% crude protein and 29% fat, although they are higher in saturated fats than most insects. They do not concentrate pesticides or mycotoxins. They are already grown and recommended for use as animal feed, but with regional legal restrictions on how this is done. For commercial use in human foods, larvae could potentially be milled and converted into a textured protein with a strong flavor. Their biggest advantage over other insects is their ability to convert waste into food, generating value and closing nutrient loops as they reduce pollution and costs. This general advantage is also their greatest disadvantage, for the social stigmas and legal prohibitions against eating organisms that eat waste are added to extant taboos facing insect consumption.

  12. Effect of Musa spp. extract on eggs and larvae of gastrointestinal nematodes from infected sheep

    Directory of Open Access Journals (Sweden)

    Natalie Neuwirt

    2015-12-01

    Full Text Available Helminthes are listed as one of the main problems facing the development of goat and sheep production. Haemonchus contortus is the specie that causes greatest negative impact in ranching. Resistance to anti-parasitic drugs and demand for residue-free animal-derived food products has elevated the importance of herbal treatments. The aim of this study was to develop an extract of Musa spp. and assess by in vitro testing, the anthelmintic effect on eggs and larvae in the gastrointestinal nematodes in sheep. Stool samples from sheep naturally infected were used to obtain eggs and larvae and was then followed by a test of hatchability and a larval migration inhibition test. In vitro tests on the inhibition of larval hatchability at concentrations of 160 and 180 mg mL-1 of larval extracts and inhibition of migration at concentrations of 800 and 1000 mg mL-1 were observed. The results indicate that the use of banana leaf has an anthelmintic effect and that in vivo studies on the applicability of this technology to the field should be made to further understanding and bring more information to what has already been revealed in this study.

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    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

  15. Proximate composition, nutritionally valuable minerals and the effects of some salts on the functional properties of silkworm (anaphe infracta) larvae

    International Nuclear Information System (INIS)

    Adeyeye, E.L.

    2008-01-01

    The investigations of the silkworm (Anaphe ilifracta) larvae on dry weight basis showed that total ash, crude fat and fibre values were low while crude protein and carbohydrate values were high. Fe, In, Mg and P were high while Na, Cu, Ni, K, Ca, Mn, Co, Cr were low. The lowest gelation concentration varied between 6.0 in 1.0% Na/sub 2/ SO/sub 3/ and 140 in 20.0% NaCI, NaNO/sub 3/ and Na/sub 2/ CO/sub 3/ With low CV%. All the water absorption capacity values were generally high, the highest being in NaNO/sub 3/. The oil emulsion capacities were generally low whereas the oil emulsion stability was good in all the salts. The isoelectric point under pH solubility depended on the type of salt solution under consideration. These results make A infracta larvae useful in some food formulations. (author)

  16. 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.

  17. 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.)

  18. Fish protein hydrolysates: application in deep-fried food and food safety analysis.

    Science.gov (United States)

    He, Shan; Franco, Christopher; Zhang, Wei

    2015-01-01

    Four different processes (enzymatic, microwave-intensified enzymatic, chemical, and microwave-intensified chemical) were used to produce fish protein hydrolysates (FPH) from Yellowtail Kingfish for food applications. In this study, the production yield and oil-binding capacity of FPH produced from different processes were evaluated. Microwave intensification significantly increased the production yields of enzymatic process from 42% to 63%. It also increased the production yields of chemical process from 87% to 98%. The chemical process and microwave-intensified chemical process produced the FPH with low oil-binding capacity (8.66 g oil/g FPH and 6.25 g oil/g FPH), whereas the microwave-intensified enzymatic process produced FPH with the highest oil-binding capacity (16.4 g oil/g FPH). The FPH from the 4 processes were applied in the formulation of deep-fried battered fish and deep-fried fish cakes. The fat uptake of deep-fried battered fish can be reduced significantly from about 7% to about 4.5% by replacing 1% (w/w) batter powder with FPH, and the fat uptake of deep-fried fish cakes can be significantly reduced from about 11% to about 1% by replacing 1% (w/w) fish mince with FPH. Food safety tests of the FPH produced by these processes demonstrated that the maximum proportion of FPH that can be safely used in food formulation is 10%, due to its high content of histamine. This study demonstrates the value of FPH to the food industry and bridges the theoretical studies with the commercial applications of FPH. © 2015 Institute of Food Technologists®

  19. 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)

  20. 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...

  1. Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

    International Nuclear Information System (INIS)

    Wolfe, M. F.; Schwartz, G. J. B.; Singaram, S.; Tjeerdema, R. S.

    1997-01-01

    Experiments were conducted to determine the impact of dispersing agents on petroleum hydrocarbons (PH) bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation and metabolic transformation of a model PH, ( 1 4C)naphthalene, were measured and compared with Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527, and undispersed preparations of PBCO. The model food chain consisted of a primary algae producer and a primary rotifer consumer. Results showed that uptake of naphthalene increased significantly in the presence of a dispersant in algae. A significant increase in uptake was also recorded in rotifers via trophic transfer. Trophic transfer played a significant, sometimes even dominant, role in uptake and bioaccumulation. 27 refs., 6 figs

  2. 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

  3. Análise da dieta das larvas de 4º estádio de Cricotopus sp. (Diptera: Chironomidae, em diferentes substratos artificiais e fases hídricas, no trecho superior do rio Paraná = Diet analysis of Cricotopus sp. larvae (Diptera: Chironomidae, fourth stage, in different artificial substrates and hydrological phases, in the upper Paraná river

    Directory of Open Access Journals (Sweden)

    Adriana Felix dos Anjos

    2009-10-01

    Full Text Available No Brasil, estudos sobre hábitos alimentares das larvas de Chironomidae ainda são escassos e estas informações são importantes para entender a estrutura trófica e a organização dos ecossistemas aquáticos. Neste estudo, teve-se como objetivo identificar osprincipais itens alimentares ingeridos por Cricotopus sp. e comparar as possíveis diferenças na dieta das larvas em diferentes substratos artificiais e fases hídricas. Foram utilizados quatro tipos de substratos artificiais: madeira em forma de X (MADX, placas de nitacetal em forma de X (NITX, PVC em forma de tubo (PVCT e metal galvanizado em forma de tubo (METT, cada um com três réplicas. As coletas foram realizadas quinzenalmente, entre os meses de agosto de 2004 e dezembro de 2005. A dieta de Cricotopus sp. foi constituída por detritos, algas e hifas de fungos. Detrito foi o principal item alimentar, com valores superiores a 50% do total consumido. Os resultados indicaram que Cricotopus sp. é uma espécie coletora e, independentemente do substrato, as larvas alimentam-se dos recursos disponíveis no ambiente. Entretanto, mudanças no regime hidrológico do rio Paraná podem influenciar a disponibilidade de alimento, principalmente algumas diatomaceas como Melosira sp., consumidas em maior quantidade apenas na fase de águas baixas.In Brazil, studies on the diet of Chironomidae larvae are still scarce and these data are important to understand the trophic structure and organization of aquatic ecosystems. In this study, we identified the main food items consumed by Cricotopus sp. and compared possible differences in the larval diet at different artificial substrates and hydrological phases. We used four types of artificial substrates: X-shaped wood (MADX; X-shaped nitacetal plates (NITX; tube-shaped PVC (PVCT and tube-shaped galvanizedmetal (METT, each with three replicates. Samplings were undertaken fortnightly, between August 2004 and December 2005. Cricotopus sp. diet was

  4. 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.

  5. Concentration of radionuclides by marine organisms and their food chain

    International Nuclear Information System (INIS)

    Nakahara, Motokazu

    1993-01-01

    Accumulation of radionuclides from seawater and from food by marine organisms was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were 57 Co, 95m Tc, 103 Ru, 137 Cs, 65 Zn and 54 Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into non-radioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except 137 Cs and 54 Mn. Retention of 137 Cs and 54 Mn in the organisms one day after feeding of radioactive food was lower than 25 % of the radioactivity dosed. (author)

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Efeito de níveis crescentes de levedura de álcool em rações contendo fígado bovino sobre a performance de larvas de jundiá (Rhamdia quelen Effect of crescent levels of yeast of alcohol used in rations containing bovine liver on larvae of (Rhamdia quelen performance

    Directory of Open Access Journals (Sweden)

    Rosamari Piaia

    1997-06-01

    Full Text Available O presente trabalho foi realizado com a finalidade de avaliar o efeito de diferentes níveis de levedura sobre o desempenho inicial de larvas de Rhamdia quelen durante as trêss primeiras semanas de vida. Um total de 3000 larvas foram distribuídas em quinze grupos, em um sistema de criação com reutilização de água, termoregulada. Utilizou-se cinco tratamentos com níveis crescentes de levedura (T1 - 50%, T2 - 60%, T3 - 70%, T4 - 80% e T5 - 90% em substituição ao fígado bovino fresco. Os níveis de proteína bruta (PB e energia digestível variaram de 41,36 a 26,56% de PB e 3197 a 2789kcal ED/kg. A granulometria dos alimentos testados foi de 100 a 200mi, 200 a 400mi e 400 a 600mi para as três semanas experimentais, respectivamente. O alimento foi fornecido a vontade entre 8 e 20 horas. Dentro dos limites de proteína estudados houve efeito positivo de níveis mais elevados de PB sobre os comprimentos total e padrão e peso individual. Porém houve um efeito negativo sobre a sobrevivência das larvas de jundiá Rhamdia quelen.The present study was developed with the purpose of evaluating the effects of different protein levels in initial performance of Rhamdia quelen larvae during the first three weeks of life. The sample contained 3000 larvae distributed in fifteen groups, maintained in controlled conditions of culture and utilizing termoregulatory water re-use system. Five crescent levels of yeast (T1 50%, T2 60%, T3 70%, T4 80% and T5 90% were used in rations in substituition of bovine liver. Levels of crude protein and digestible energy varied 41,36% to 26,56% CP and from 3197 to 2789 kcal ED/kg. The granulometry of tested food was of 100 a 200mu, 200 a 400mu and 400 a 600mu for three experimental weeks respectively. Food distribution provided at ease between 8 Am and 8 Pm. Within the net protein used in this research, there was found a positive effect for the highest protein levels for total, standard lenght and individual weight

  17. 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.

  18. 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.

  19. Prospect of Sea Cucumber Culture in Indonesia as Potential Food Sources

    OpenAIRE

    Pangkey, Henneke; Lantu, Sartje; Manuand, Lusia; Mokolensang, JeffrieFredrik

    2012-01-01

    Sea cucumber is one of the sea treasures which has been used not only as luxury food for certain countries but also as medicines. Sea cucumber has become one of the most important products and it has high price in International market.For this reason, the exploitation of sea cucumber turns out to be excessive and disturbs its sustainability. Aquaculture is the best way to prevent this problem. The success of sea cucumber culture is very depend on seed availability and suitable food for larvae...

  20. Comparative proteomics and expression analysis of five genes in Epicauta chinensis larvae from the first to fifth instar.

    Directory of Open Access Journals (Sweden)

    Qiurong Li

    Full Text Available Blister beetle is an important insect model for both medicinal and pure research. Previous research has mainly focused on its biology and biochemistry, but very little data is yet available in the molecular biology. This study uses differential proteomics technology to analyze the soluble proteins extracted from each of the 5 instars larvae of Epicauta chinensis. 42 of the differentially-expressed proteins were identified successfully by MALDI-TOF/TOF-MS. Some of these proteins' function and their expression profiles are analyzed. Our analysis revealed dynamics regulation of the following proteins: Axin-like protein pry-1 (APR-1, dihydrolipoyl dehydrogenase (DLD, vitellogenin (Vg and lysozyme C (Lmz-S. APR-1 negatively regulates the Wnt signaling pathway. Its overexpression could result in embryo, leg, eye and ovary ectopica or malformation. DLD catalyzes the pyruvate into acetyl-CoA, the latter is the starting material of juvenile hormone (JH and ipsdienol biosynthesis through the MVA pathway in insects. While Vg synthesis can be regulated by JH and stimulated by food factors. So DLD may affect the synthesis of JH, ipsdienol and Vg indirectly. The activity of lysozyme is an indicator of the immunity. Nutrition/food should be taken into account for its potential role during the development of larva in the future. Among the five genes and their corresponding proteins' expression, only hsc70 gene showed a good correspondence with the protein level. This reflects the fluctuating relationship between mRNA and protein levels.

  1. Aspectos biológicos da fase adulta de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae oriunda de larvas alimentadas com Planococcus citri (Risso, 1813 (Hemiptera: Pseudococcidae Biological aspects of the adult stage of Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae originating from the larvae fed Planococcus citri (Risso, 1813 (Hemiptera: Pseudococcidae

    Directory of Open Access Journals (Sweden)

    Gerane Celly Dias Bezerra

    2006-08-01

    in cages of PVC determining sex ratio, pre-oviposition period, daily and total oviposition for 40 days on end, longevity, embryonic period and survival rate of eggs. It was found that the nymphs at the three instars and adult females given as food did not affect sex ratio, pre-oviposition period, embryonic period and longevity of adults of C. externa. The daily and total egg production by C. externa was affected by the sort of food given to the predator during the larval stage, observing a greater production when the couples were fed at the larval stage with adults females of mealybug. By assessing egg production, a higher concentration of oviposition on the first ten days of the reproductive period was found, decreasing in the next evaluations. The survival rates of eggs not differ in function of feed in the different stages of development of prey that was consumed by differents predator larvae stage.

  2. 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).

  3. 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 ...

  4. 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.

  5. 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.

  6. 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

  7. [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.

  8. Dynamics of pesticide uptake into plants: From system functioning to parsimonious modeling

    DEFF Research Database (Denmark)

    Fantke, Peter; Wieland, Peter; Wannaz, Cedric

    2013-01-01

    Dynamic plant uptake models are suitable for assessing environmental fate and behavior of toxic chemicals in food crops. However, existing tools mostly lack in-depth analysis of system dynamics. Furthermore, no existing model is available as parameterized version that is easily applicable for use...

  9. 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.

  10. CONSIDERATIONS ON THE INFLUENCE OF COMPLEXATION IN THE COPPER UPTAKE AND TRANSLOCATION

    Directory of Open Access Journals (Sweden)

    SEMAGHIUL BIRGHILA

    2014-07-01

    Full Text Available The actual knowledge about food and the environment underlines the fact that agricultural and environmental sciences must solve various problems regarding copper uptake from soil to plants and its bioaccumulation, being important issues for copper concentration in crops and also for phytoremediation of polluted soils. We studied the relation between the form in which copper is applied to soil and the consequential copper bioavailability, uptake and translocation, using as examples simple and complex copper compounds. The copper concentration in basil plants harvested from soils treated with copper compounds and the calculated values of transfer coefficient, translocation factor, bioaccumulation factor, and uptake coefficient demonstrated that the ionic copper (from simple salts is not necessarily easier to uptake than complex ions, but is easier translocated in plants, while the copper given as complex ions is most likely to be retained by roots. The results indicated that the involvement of copper complexes in agricultural treatments is a solution for soils phytoremediation, concerning the phytostabilization technology.

  11. Effect of irradiated food on life cycle of Trogoderma granarium by gamma irradiations infesting stored barley (Hordum vulgare)

    International Nuclear Information System (INIS)

    Sisodiya, Manju; Singhvi, P.M.

    2012-01-01

    To study the effect of irradiated food on the life cycle of Trogoderma granarium crushed barley were irradiated by Gamma irradiations. Fresh eggs were collected from stock culture for getting newly hatched first instar larvae. Twenty, first instar larvae were collected and transferred to the culture tubes containing irradiated food. The larva was observed till the emergence of adults. To calculate the survivality of insects the newly emerged adults were counted daily till the last adult and the emerged beetles were removed. The observation was also made in regard to the time required for adult emergence. The test insect was reared on Gamma irradiated food and survival rate, developmental period and growth index were recorded in different does as 0.1, 0.2, 0.3, 0.4 and 0.5 KGy. The survival rate, developmental period and growth rate of test insect were recorded as 95%, 26.00 and 0.049 respectively at highest dose of 0.5 KGy. Where as 96.67%, 25.33 and 0.051 at lowest dose of 0.1 KGy was recorded. In control condition, they were 98.33%, 29.67 and 0.043 respectively. Irradiation against barley grains had no such effect on the developmental period, survival rate and growth index of Trogoderma granarium. It provides effective alternative to fumigants chemical pesticides which have numerous hazards and create environmental pollution. (author)

  12. The impact of food type, temperature and starvation on larval development of Balanus amphitrite Darwin (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, D.V.; Anil, A.C.

    The impact of diatom food species (Chaetoceros calcitrans and Skeletonema costatum), temperature and starvation on the larval development of Balanus amphitrite was evaluated. Starvation threshold levels for different ages of larvae (0- to 5-day...

  13. Gbu Glycine Betaine Porter and Carnitine Uptake in Osmotically Stressed Listeria monocytogenes Cells

    Science.gov (United States)

    Mendum, Mary Lou; Smith, Linda Tombras

    2002-01-01

    The food-borne pathogen Listeria monocytogenes grows actively under high-salt conditions by accumulating compatible solutes such as glycine betaine and carnitine from the medium. We report here that the dominant transport system for glycine betaine uptake, the Gbu porter, may act as a secondary uptake system for carnitine, with a Km of 4 mM for carnitine uptake and measurable uptake at carnitine concentrations as low as 10 μM. This porter has a Km for glycine betaine uptake of about 6 μM. The dedicated carnitine porter, OpuC, has a Km for carnitine uptake of 1 to 3 μM and a Vmax of approximately 15 nmol/min/mg of protein. Mutants lacking either opuC or gbu were used to study the effects of four carnitine analogs on growth and uptake of osmolytes. In strain DP-L1044, which had OpuC and the two glycine betaine porters Gbu and BetL, triethylglycine