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Ecologia alimentar da toninha Pontoporia blainvillei (Cetacea); Feeding ecology of franciscana dolphin Pontoporia blainvillei (Cetacea)

Silva, Barbara Henning
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/12/2011 PT
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Originalmente, a teoria de nicho ecológico fundamenta-se em indivíduos de uma espécie sendo ecologicamente equivalentes por utilizarem os recursos de forma similar. Portanto, o nicho de uma espécie é definido em termos do uso médio de recursos. Porém, a qualidade e abundância de recursos consumidos, sexo, idade ou morfotipo do consumidor influenciam o comportamento alimentar individual. Estudos recentes sobre forrageamento ótimo tem foco de interesse na variação interindividual no uso de recursos. Ao longo da sua área de distribuição são reconhecidas populações da toninha Pontoporia blainvillei (Cetacea) e no litoral paulista, possivelmente hajam três subpopulações dessa espécie: norte, centro e sul. Meu primeiro objetivo foi investigar se há variação na dieta entre essas três subpopulações de toninha. Adicionalmente, investiguei quais fatores entre sazonalidade, sexo e idade dos indivíduos poderiam estruturar a dieta em uma dessas subpopulações (central). Utilizei 58 indivíduos provenientes de captura acidental no litoral paulista, com representantes das regiões norte, centro e sul. A amostra incluiu juvenis e adultos de ambos os sexos, capturados em todas as estações do ano. Identifiquei as espécies nos conteúdos estomacais usando os otólitos de peixes e os bicos de lulas. Estimei o tamanho das presas utilizando regressões com as medidas dessas estruturas e investiguei a estruturação da dieta usando um índice de variação da dieta. Houve uma clara variação na dieta ente as subpopulações paulistas...

Chitinolytic activities in the gut of Aedes aegypti (Diptera : Culicidae) larvae and their role in digestion of chitin-rich structures

Souza-Neto, J. A.; Gusmao, D. S.; Lemos, FJA
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 717-724
ENG
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Mosquito larvae are believed to be capable of digesting chitin, an insoluble polysaccharide of N-acetylglucosamine, for their nutritional benefit. Studies based on physiological and biochemical assays were conducted in order to detect the presence of chitinase activities in the gut of the detritus-feeding Aedes aegypti larvae. Larvae placed for 24 h in suspensions of chitin azure were able to digest the ingested chitin. Semi-denaturing PAGE using glycol chitin and two fluorogenic substrate analogues showed the presence of two distinct chitinase activities: an endochitinase that catalyzed the hydrolysis of chitin and an endochitinase that cleaved the short substrates [4MU(GlcNAc)(3)] and [4MU(GlcNAc)(2)] that hydrolyzed the chitobioside [4MU(GlcNAc)(2)]. The endochitinase had an extremely broad pH-activity against glycol chitin and chitin azure, pH ranging from 4.0 to 10.0. When the substrate [4MU(GlcNAc)(3)] was used, two activities were observed at pH ranges 4.0-6.0 and 8.0-10.0. Chitinase activity against [4MU(GlcNAc)(3)] was detected throughout the gut with the highest specific activity in the hindgut. The pH of the gut contents was determined by observing color changes in gut after feeding the larvae with color indicator dyes. It was observed a correlation between the pH observed in the gut of feeding larvae (pH 10-6.0) and the optimum pH for gut chitinase activities. In this work...

High prokaryotic biodiversity associated with gut contents of the holothurian Molpadia musculus from the Nazare Canyon (NE Atlantic)

Amaro, Teresa; Luna, Gian Marco; Danovaro, Roberto; Billett, David S. M.; Cunha, Marina R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
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Sediments in the Nazare Canyon (NE Atlantic) are inhabited by unexpectedly high abundances of the deposit-feeding holothurian Molpadia musculus. The energetic demand of such a large megafaunal biomass is presumably high and requires the efficient exploitation of the food inputs coming from the photic zone. We hypothesise the existence of cooperative interactions between these deep-sea holothurians and prokaryotes in their guts. To investigate these interactions, sediment samples and holothurians were collected at ca. 3500 m depth using a Remote Operated Vehicle (ROV) and an incubation chamber used to "harvest" faeces from the holothurian. In all of these samples (ingested sediment from different sectors of the holothurian gut content, faeces and sediments) we determined total prokaryotic abundance, the relative abundance of Bacteria and Archaea (by means of Catalysed Reporter Deposition-Fluorescence in situ Hybridisation) and bacterial diversity (by means of fingerprinting techniques: ARISA and T-RFLP). Prokaryotic abundances and bacterial diversity in the holothurian gut were very high (up to 10(5) bacterial Operational Taxonomic Units) and significantly greater than in surrounding bottom sediments. Archaea represented a key component within the gut of the holothurians and in certain tracts dominated the prokaryotic assemblage. We also found that ca. 40% of bacterial OTUs were associated uniquely with the gut contents (i.e....

1-O-Alkylglyceryl Ether Lipids of the Gut Walls and Contents of an Abyssal Holothurian (Oneirophanta mutabilis)

Santos,Vera L. C. S.; Billett,David S. M.; Wolff,George A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2002 EN
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A study of the glyceryl ether composition of free lipids of gut walls and contents of an abyssal holothurian species, Oneirophanta mutabilis has been carried out. A series of saturated and unsaturated 1-O-alkylglyceryl ethers with alkyl side chains ranging from C15 to C21 were detected inthe gut walls and contents of O. mutabilis. Glyceryl ethers accounted for 5-12% of the total free lipids contents. Foregut, midgut and hindgut walls and contents have identical 1-O-alkylglyceryl ether compositions. The C16:0, C16:1, C17:0, C18:0 and C18:1 are the main glyceryl ethers with C18:0 being dominant. The total organic carbon (TOC) and nitrogen (N) contents were also evaluated in gut contents of the digestive tract of O. mutabalis and these decreased from foregut to hindgut. The average assimilation efficiencies were estimated to be 40 and 55% for TOC and N respectively.

Feeding habits of Chironomid larvae (Insecta: Diptera) from a stream in the Floresta da Tijuca, Rio de Janeiro, Brazil

Henriques-Oliveira,A. L.; Nessimian,J. L.; Dorvillé,L. F. M.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2003 EN
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Chironomids larvae are frequently one of the most abundant and diverse groups of insects in several kinds of aquatic environments. Also, they play a major role in the aquatic food webs, representing a major link among producers and secondary consumers. This work investigates the feeding behavior of the chironomid larvae present in the Rio da Fazenda, situated in the Parque Nacional da Tijuca, Rio de Janeiro, Brazil, between August 1994 and May 1995. Algae, fungi, pollen, leaf and wood fragments, animal remains, detritus and silt were the main gut contents found in the larvae studied. The main food item ingested by the larvae was detritus, except for the Stenochironomus whose main food source was leaf and wood fragments. Tanypodinae exhibited a large quantity of animal remains of several kinds in the diet. During the period studied it was observed that the diet of 16 genera (out of 24 studied) varied. Tanypodinae had mainly coarse particulate organic matter (> 1 mm) in the gut contents, while Chironominae and Orthocladiinae had fine particulate organic matter (< 1 mm).

Cladocerans from gut contents of fishes associated to macrophytes from Taquari River Basin, MS, Brazil

Güntzel,Adriana Maria; Melo,Ilze Katsue Morita; Roche,Kennedy Francis; Silva,Valéria Flávia Batista da; Pompiani,Priscila Gusmão
Fonte: Associação Brasileira de Limnologia Publicador: Associação Brasileira de Limnologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2012 EN
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AIM: The aim of this study was to identify the cladocerans species from the gut contents of fishes sampled in an oxbow lake from Taquari River Basin, MS, with the specific view of investigating the importance of these crustaceans in the fishes diets; METHODS: Sampling was carried out in April and August of 2005 (dry season) and January of 2006 (wet season). The fish were captured with a sieve. In the laboratory, individuals were identified and stomachs were removed and weighed. The stomach contents were identified, and a Feeding Index calculated; RESULTS: The items most consumed by fishes were filamentous algae, Cladocera and detritus. The Cladocera were especially important in the August and January samples, and consisted primarily of Chydoridae; cladocerans were most consumed by species of Serrapinnus and by Mesonauta festivus. Fish fed more in April, with decreases occurring in stomach fullness on the other two sampling dates. CONCLUSIONS: Cladocerans associated with macrophytes may be an important food source for small fish individuals in marginal lakes from Taquari River Basin. The relative importance of the Chydoridae in the guts may have been due to the high relative abundance and species richness of this group in the environment. A short discussion on fish feeding habits was included in the text.

The Earthworm Gut: an Ideal Habitat for Ingested N2O-Producing Microorganisms

Horn, Marcus A.; Schramm, Andreas; Drake, Harold L.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /03/2003 EN
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The in vivo production of nitrous oxide (N2O) by earthworms is due to their gut microbiota, and it is hypothesized that the microenvironment of the gut activates ingested N2O-producing soil bacteria. In situ measurement of N2O and O2 with microsensors demonstrated that the earthworm gut is anoxic and the site of N2O production. The gut had a pH of 6.9 and an average water content of approximately 50%. The water content within the gut decreased from the anterior end to the posterior end. In contrast, the concentration of N2O increased from the anterior end to the mid-gut region and then decreased along the posterior part of the gut. Compared to the soil in which worms lived and fed, the gut of the earthworm was highly enriched in total carbon, organic carbon, and total nitrogen and had a C/N ratio of 7 (compared to a C/N ratio of 12 in soil). The aqueous phase of gut contents contained up to 80 mM glucose and numerous compounds that were indicative of anaerobic metabolism, including up to 9 mM formate, 8 mM acetate, 3 mM lactate, and 2 mM succinate. Compared to the soil contents, nitrite and ammonium were enriched in the gut up to 10- and 100-fold, respectively. The production of N2O by soil was induced when the gut environment was simulated in anoxic microcosms for 24 h (the approximate time for passage of soil through the earthworm). Anoxia...

The beta-glucosidase in the gut contents of the snail Achatina achatina.

Umezurike, G M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/08/1976 EN
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1. The enzyme beta-glucosidase (beta-D-glucoside glucohydrolase, EC 3.2.1.21) from the gut contents of active Achatina achatina exists in two molecular forms, beta-glucosidase C (mol.wt. about 82000) and D (mol.wt. about 41000). 2. Only the lower-molecular-weight species was found in the gut contents of aestivating snails or in extracts from their digestive glands and washed gut walls. 3. On re-activation of some aestivating snails, betion of ATP and Mg2+ to the isolated gut contents or to extracts from washed gut walls led to the formation of higher-molecular-weight forms of the enzyme, beta-glucosidase A (mol.wt. about 329000) and beta-glucosidase B (mol.wt. about 165000). 5. All these forms of the enzyme have similar pH optimum (pH 5.0-5.6). 6. The Michaelis constants (Km) and heat stability of the enzyme increased with increasing molecular complexity.

Mechanism of inhibition of microsomal mixed-function oxidation by the gut-contents inhibitor of the southern armyworm (Prodenia eridania)

Orrenius, S.; Berggren, M.; Moldéus, P.; Krieger, R. I.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1971 EN
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A potent inhibitor of microsomal mixed-function oxidation reactions in insects had previously been isolated and partially purified from the gut contents of Prodenia eridania and shown to be associated with proteinase activity. Incubation of rat liver microsomal fraction with low concentrations of this inhibitor led to solubilization of NADPH–cytochrome c reductase, which was paralleled by the inactivation of reduction of cytochrome P-450 by NADPH and by the inhibition of NADPH-linked benzo[3,4]pyrene hydroxylation and aminopyrine demethylation. There was little or no effect on cytochromes b5 and P-450, nor was the capacity of the latter catalyst to combine with exogenous substrates decreased. Contrary to the findings with NADPH, preincubation of microsomal fraction with the inhibitor did not cause a significant decrease in the rate of cytochrome P-450 reduction by NADH, supporting the assumption that different catalysts are involved in the electron transfer from NADH and NADPH to cytochrome P-450. The findings indicate the importance of taking the possible presence of endogenous inhibitors into consideration when evaluating low or absent mixed-function oxidation activities found in insect systems in vitro.

The gradient of electrical potential difference and of sodium and potassium of the gut contents along the caecum and colon of normal and sodium-depleted rats

Edmonds, C. J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1967 EN
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1. The Na, K and water content of stools, and of gut contents removed from the terminal ileum, caecum and colon were determined in normal and Na-depleted rats and the p.d. across the colon wall measured at the site of removal of each specimen.

Gut Contents as Direct Indicators for Trophic Relationships in the Cambrian Marine Ecosystem

Vannier, Jean
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 26/12/2012 EN
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Present-day ecosystems host a huge variety of organisms that interact and transfer mass and energy via a cascade of trophic levels. When and how this complex machinery was established remains largely unknown. Although exceptionally preserved biotas clearly show that Early Cambrian animals had already acquired functionalities that enabled them to exploit a wide range of food resources, there is scant direct evidence concerning their diet and exact trophic relationships. Here I describe the gut contents of Ottoia prolifica, an abundant priapulid worm from the middle Cambrian (Stage 5) Burgess Shale biota. I identify the undigested exoskeletal remains of a wide range of small invertebrates that lived at or near the water sediment interface such as hyolithids, brachiopods, different types of arthropods, polychaetes and wiwaxiids. This set of direct fossil evidence allows the first detailed reconstruction of the diet of a 505-million-year-old animal. Ottoia was a dietary generalist and had no strict feeding regime. It fed on both living individuals and decaying organic matter present in its habitat. The feeding behavior of Ottoia was remarkably simple, reduced to the transit of food through an eversible pharynx and a tubular gut with limited physical breakdown and no storage. The recognition of generalist feeding strategies...

Molecular and microscopic analysis of the gut contents of abundant rove beetle species (Coleoptera, Staphylinidae) in the boreal balsam fir forest of Quebec, Canada

Klimaszewski, Jan; Morency, Marie-Josee; Labrie, Philippe; Séguin, Armand; Langor, David; Work, Timothy; Bourdon, Caroline; Thiffault, Evelyne; Paré, David; Newton, Alfred F.; Thayer, Margaret K.
Fonte: Pensoft Publishers Publicador: Pensoft Publishers
Tipo: Artigo de Revista Científica
Publicado em 20/11/2013 EN
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Experimental research on beetle responses to removal of logging residues following clearcut harvesting in the boreal balsam fir forest of Quebec revealed several abundant rove beetle (Staphylinidae) species potentially important for long-term monitoring. To understand the trophic affiliations of these species in forest ecosystems, it was necessary to analyze their gut contents. We used microscopic and molecular (DNA) methods to identify the gut contents of the following rove beetles: Atheta capsularis Klimaszewski, Atheta klagesi Bernhauer, Oxypoda grandipennis (Casey), Bryophacis smetanai Campbell, Ischnosoma longicorne (Mäklin), Mycetoporus montanus Luze, Tachinus frigidus Erichson, Tachinus fumipennis (Say), Tachinus quebecensis Robert, and Pseudopsis subulata Herman. We found no apparent arthropod fragments within the guts; however, a number of fungi were identified by DNA sequences, including filamentous fungi and budding yeasts [Ascomycota: Candida derodonti Suh & Blackwell (accession number FJ623605), Candida mesenterica (Geiger) Diddens & Lodder (accession number FM178362), Candida railenensis Ramirez and Gonzáles (accession number JX455763), Candida sophie-reginae Ramirez & González (accession number HQ652073), Candida sp. (accession number AY498864)...

Bacterial Community Composition in the Gut Content and Ambient Sediment of Sea Cucumber Apostichopus japonicus Revealed by 16S rRNA Gene Pyrosequencing

Gao, Fei; Li, Fenghui; Tan, Jie; Yan, Jingping; Sun, Huiling
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 26/06/2014 EN
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The composition of the bacterial communities in the contents of the foregut and hindgut of the sea cucumber Apostichopus japonicus and in the ambient surface sediment was surveyed by 16S rRNA gene 454-pyrosequencing. A total of 188,623 optimized reads and 15,527 operational taxonomic units (OTUs) were obtained from the ten gut contents samples and four surface sediment samples. The sequences in the sediments, foregut contents, and hindgut contents were assigned to 38.0±4.7, 31.2±6.2 and 27.8±6.5 phyla, respectively. The bacterial richness and Shannon diversity index were both higher in the ambient sediments than in the gut contents. Proteobacteria was the predominant phylum in both the gut contents and sediment samples. The predominant classes in the foregut, hindgut, and ambient sediment were Holophagae and Gammaproteobacteria, Deltaproteobacteria and Gammaproteobacteria, and Gammaproteobacteria and Deltaproteobacteria, respectively. The potential probiotics, including sequences related to Bacillus, lactic acid bacteria (Lactobacillus, Lactococcus, and Streptococcus) and Pseudomonas were detected in the gut of A. japonicus. Principle component analysis and heatmap figure showed that the foregut, hindgut, and ambient sediment respectively harbored different characteristic bacterial communities. Selective feeding of A. japonicus may be the primary source of the different bacterial communities between the foregut contents and ambient sediments.

Discrimination of grasshopper (Orthoptera: Acrididae) diet and niche overlap using next-generation sequencing of gut contents

McClenaghan, Beverly; Gibson, Joel F; Shokralla, Shadi; Hajibabaei, Mehrdad
Fonte: John Wiley & Sons, Ltd Publicador: John Wiley & Sons, Ltd
Tipo: Artigo de Revista Científica
EN
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Species of grasshopper have been divided into three diet classifications based on mandible morphology: forbivorous (specialist on forbs), graminivorous (specialist on grasses), and mixed feeding (broad-scale generalists). For example, Melanoplus bivittatus and Dissosteira carolina are presumed to be broad-scale generalists, Chortophaga viridifasciata is a specialist on grasses, and Melanoplus femurrubrum is a specialist on forbs. These classifications, however, have not been verified in the wild. Multiple specimens of these four species were collected, and diet analysis was performed using DNA metabarcoding of the gut contents. The rbcLa gene region was amplified and sequenced using Illumina MiSeq sequencing. Levins’ measure and the Shannon–Wiener measure of niche breadth were calculated using family-level identifications and Morisita’s measure of niche overlap was calculated using operational taxonomic units (OTUs). Gut contents confirm both D. carolina and M. bivittatus as generalists and C. viridifasciata as a specialist on grasses. For M. femurrubrum, a high niche breadth was observed and species of grasses were identified in the gut as well as forbs. Niche overlap values did not follow predicted patterns, however, the low values suggest low competition between these species.

First gut contents in a Cretaceous sea turtle

Kear, Benjamin Philip
Fonte: Royal Society Publicador: Royal Society
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
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Modern sea turtles utilize a variety of feeding strategies ranging from herbivory to omnivory. In contrast, the diets of fossil sea turtles are poorly known. This study reports the first direct evidence: inoceramid bivalve shell pieces (encased in phosphatic material) preserved within the body cavities of several small protostegid turtles (cf. Notochelone) from the Lower Cretaceous of Australia. The shell fragments are densely packed and approximately 5–20 mm across. Identical shell accumulations have been found within coprolite masses from the same deposits; these are of a correct size to have originated from Notochelone, and indicate that benthic molluscs were regular food items. The thin, flexible inoceramid shells (composed of organic material integrated into a prismatic calcite framework) appear to have been bitten into segments and ingested, presumably in conjunction with visceral/mantle tissues and encrusting organisms. Although protostegids have been elsewhere interpreted as potential molluscivores, their primitive limb morphology is thought to have limited them to surface feeding. However, the evidence here that at least some forms were able to utilize benthic invertebrate prey indicates that, like modern sea turtles, protostegids probably exhibited a much broader range of feeding habits.; © 2005 The Royal Society

Cryptic dietary components reduce dietary overlap among sympatric butterflyfishes (Chaetodontidae)

Nagelkerken, I.; van der Velde, G.; Wartenbergh, S.; Nugues, M.; Pratchett, M.
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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This study used three different methods to ascertain dietary composition for 21 Chaetodontidae species co-occurring on a single fringing reef in Derawan Island, East Kalimantan, Indonesia. The combination of in situ feeding observations, examination of gut contents and stable-isotope analyses was expected to identify previously unresolved prey items that contribute to dietary separation. In situ feeding observations identified five species that feed predominantly on anthozoans (Chaetodon baronessa, Chaetodon bennetti, Chaetodon lunulatus, Chaetodon punctatofasciatus and Chaetodon speculum). Stable-isotope ratios for these species, as well as for Chaetodon ornatissimus (for which no feeding observations were completed), were very similar and consistent with diets comprising mostly anthozoans. Feeding observations, however, showed that they mostly fed on different coral species, while the identifiable portion of their gut contents showed clear separation based on cryptic dietary components. For example, C. baronessa and C. bennetti appeared to ingest annelid worms during the course of coral feeding, whereas gut contents of C. punctatofasciatus and C. speculum were dominated by crustaceans. In situ feeding observations further identified the following groups: coral–bottom feeders...

Unusual gut contents in a Cretaceous ichthyosaur.

Kear, Benjamin P; Boles, Walter E; Smith, Elizabeth T
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 07/11/2003 EN
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Despite ichthyosaurs being one of the most extensively studied Mesozoic marine reptile groups, there is little documented direct evidence of dietary habits in most taxa. Here, we report the discovery of hatchling-sized marine protostegid turtle remains and an enantiornithine bird (in association with actinopterygian fish and phosphatic nodules) within the body cavity of a gravid female ichthyosaur (Platypterygius longmani) from the Lower Cretaceous of Australia; this is the first evidence, to our knowledge, of feeding by ichthyosaurs upon both turtles and birds. The exceptionally preserved gut contents show little evidence of digestion, suggesting consumption shortly before the ichthyosaur's death. Poor swimming ability may have made hatchling turtles easy prey that could have been either swallowed whole or processed by shake feeding. Ingestion of bird remains probably occurred through scavenging. Opportunistic feeding on vertebrates is at odds with existing interpretations of dietary habits in Cretaceous ichthyosaurs, which favour predation primarily upon cephalopods. Such specialization is considered a contributing factor in the group's ultimate extinction. However, the evidence here that at least some forms were able to use a wide range of available food types suggests that the decline of ichthyosaurs in the mid-Cretaceous may be linked to other factors such as competition with ecologically analogous pursuit predators.

Effectiveness of Annealing Blocking Primers versus Restriction Enzymes for Characterization of Generalist Diets: Unexpected Prey Revealed in the Gut Contents of Two Coral Reef Fish Species

Leray, Matthieu; Agudelo, Natalia; Mills, Suzanne C.; Meyer, Christopher P.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 08/04/2013 EN
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46.3%
Characterization of predator-prey interactions is challenging as researchers have to rely on indirect methods that can be costly, biased and too imprecise to elucidate the complexity of food webs. DNA amplification and sequencing techniques of gut and fecal contents are promising approaches, but their success largely depends on the ability to amplify the taxonomic array of prey consumed and then match prey amplicons with reference sequences. When little a priori information on diet is available or a generalist predator is targeted, versatile primer sets (also referred to as universal or general primers) as opposed to group- or species-specific primer sets are the most powerful to unveil the full range of prey consumed. However, versatile primers are likely to preferentially amplify the predominant, less degraded predator DNA if no manipulation is performed to exclude this confounding DNA template. In this study we compare two approaches that eliminate the confounding predator template: restriction digestion and the use of annealing blocking primers. First, we use a preliminary DNA barcode library provided by the Moorea BIOCODE project to 1) evaluate the cutting frequency of commercially available restriction enzymes and 2) design predator specific annealing blocking primers. We then compare the performance of the two predator removal strategies for the detection of prey templates using two versatile primer sets from the gut contents of two generalist coral reef fish species sampled in Moorea. Our study demonstrates that blocking primers should be preferentially used over restriction digestion for predator DNA removal as they recover greater prey diversity. We also emphasize that a combination of versatile primers may be required to best represent the breadth of a generalist's diet.

New 14C Ages on Cellulose from Diprotodon gut contents: Explorations in Oxidisation Chemistry and Combustion

Gillespie, Richard; Fifield, L Keith; Levchenko, Vladimir Alexander; Wells, Roderick
Fonte: University of Arizona Publicador: University of Arizona
Tipo: Artigo de Revista Científica
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46.14%
We report radiocarbon ages on cellulose isolated from the gut contents of a Diprotodon found at Lake Callabonna, South Australia. The maximum age obtained corresponds to a minimum age of >53,400 BP for this extinct giant marsupial. This is older than, and

Aspectos de comportamento alimentar e dieta da tartaruga marinha, Chelonia mydas no litoral norte paulista; Some aspects on feeding behaviour of the green turtle, Chelonia mydas, in the northern littoral of State of São Paulo

Sazima, Ivan; Sazima, Marlies
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/1983 POR
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Feeding behavior of immature green turtles, Chelonia mydas, has been observed on rocky shores along the northern part of State of São Paulo, southeastern Brazil. This turtle forages on underwater ledges, at depths of 1 to 3 m and grazes on benthic algae. The turtle seems to visually scan the algae during feeding and moves slowly, walking from one patch of vegetation to another. Gut contents of four individuals (331-452 mmCCL) consisted mainly of red and brown algae. Comparisons between gut contents and algae growing at the grazing sites, together with scanning behavior suggest selective feeding. Syntopic large herbivorous fishes of the genera Kyphosus, Sparisma, and Acanthurus showed little feeding overlap with the green turtle.