Tesi: "Larves – Physiologie"

1

Holbach, Marine. "La sensibilité des larves de pectinidés aux conditions d'élevage : le flux ouvert comme alternative aux mortalités massives". Thesis, Brest, 2014. http://www.theses.fr/2014BRES0128/document.

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Abstract (sommario):

Dans de nombreux pays, l’aquaculture de pectinidés dépend aujourd’hui du succès de la production contrôlée de juvéniles. Néanmoins, les fortes variations des taux d’éclosion des oeufs et de la survie larvaire, enregistrées à ce jour, rendent cette production imprévisible. Les élevages larvaires en flux ouvert de coquilles Saint-Jacques (Pecten maximus) ont été développés en Norvège et présentent des résultats prometteurs. Malheureusement, les rendements de production encore faibles et l’impossibilité de travailler à fortes densités restent un frein majeur au développement de cette technique. En France, une technique en flux-ouvert, en petit volume (5 L), et à forte densité (≤ 300 larves mL-1) a été développée pour les ostréidés. Des expériences préliminaires visant à décliner ce système d’élevage aux larves de P. maximus se sont avérées infructueuses : retard de croissance et forte mortalité en quelques jours. Il est reconnu que les larves de pectinidés doivent faire face à des contraintes diverses en écloserie : bactériologiques, physiologiques et environnementales. Elles sont également plus sensibles que les larves des autres espèces de bivalves comme par exemple l’huître japonaise (Crassostrea gigas). Il apparait donc nécessaire aujourd’hui d’identifier plus clairement l’origine des phénomènes perturbant le bon développement des larves en flux ouvert afin d’améliorer la qualité des élevages et les rendements larvaires. Grâce à l’étude et à la compréhension des mécanismes physiologiques impliqués dans la lutte contre le stress des larves de P. maximus en flux ouvert, ce projet de doctorat donne des clés permettant d’améliorer cette technique d’élevage tout en limitant l’utilisation de produits chimiques en milieu contrôlé
In many countries, aquaculture of pectinids depends on the success of artificial spat production in hatchery. This production is always unpredictable due to the variability of hatching rate and larval survival. Flow-through larval rearing systems were developed in Norway for the King scallop Pecten maximus and showed promising results. Unfortunately the system needs to be optimized since the larval yields and the densities used are still relatively low. In France, a small-scale (5 L) and high-density (≤ 300 larva mL-1) flow-through larval rearing system was successfully developed for oysters. First trials in such system and in similar conditions with P.maximus failed as we registered slower growth and high mortality rate in only a few days. It is known that pectinids larvae are more sensitive to environmental conditions than the oyster Crassostrea gigas, for example.Nowadays, it is important to identify and to understand the phenomena disturbing larval development in flowthrough system to improve larval quality and production yields. This doctoral project provided some indications how improving P. maximus flowthrough rearing system while limiting the use of antibiotic through a better understanding the physiological mechanisms involved in the larval response to a stressful environment

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2

Beniers, Julian. "Enzyme localization in the digestive tract of black soldier fly larvae, by freeze-substitution and glycol methacrylate inclusion". Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/69802.

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3

Mani-Ponset, Laurence. "Evolution des mécanismes nutritionnels au cours du développement postembryonnaire chez deux poissons téléostéens d'intérêt aquacole : le loup, "Dicentrarchus labrax" et le sandre, "Stizostedion lucioperca"". Montpellier 2, 1995. http://www.theses.fr/1995MON20192.

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Abstract (sommario):

L'etude comparee de l'evolution des mecanismes nutritionnels au cours des premiers jours de vie libre, chez des larves de loup et de sandre nourries de zooplancton ou a jeun, nous a conduit a nous pencher successivement sur la resorption de la vesicule vitelline, sur l'organogenese de l'intestin, du foie, du pancreas et du muscle squelettique ainsi que sur les metabolismes glucidique et lipidique durant les differentes periodes du developpement postembryonnaire. L'addition de glucose et d'insuline a l'eau d'elevage nous a permis de demontrer que ces molecules pouvaient etre absorbees et assimilees par les larves, ce qui offre des perspectives de recherche appliquee interessantes. L'ensemble de nos observations debouche sur le decoupage du developpement postembryonnaire en quatre phases physiologiques principales et la mise en evidence d'anomalies pathologiques liees a l'alimentation. Nos recherches s'appuient sur une investigation histologique faisant appel a la microscopie (photonique et electronique a transmission), a l'histochimie, a l'histoenzymologie et a l'immunofluorescence

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4

Rotllant, Estelrich Guiomar. "Ontogénèse anatomo-fonctionnelle des centres neuroendocrines pédonculaires chez le homard européen, "Homarus gammarus" (L. , 1758)". Montpellier 2, 1993. http://www.theses.fr/1993MON20079.

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Ce travail decrit l'ontogenese des centres neuroendocrines pedonculaires chez homarus gammarus au cours du developpement embryonnaire et postembryonnaire. La mise en place des structures du pedoncule oculaire a ete suivie par microscopie photonique et electronique; leur activite a ete etudiee par immunocytochimie et hybridation in situ. La formation des lobes procephaliques est progressive pendant le developpement embryonnaire. Le stade nauplius presente deux masses nerveuses, l'une a devenir visuel, l'autre a devenir neuroendocrine. L'organe de bellonci est observable des la moitie du metanauplius. Il presente une grande diversite ultrastructurale avec predominance de structures en corps en oignon, quel que soit le stade du developpement. Le complexe organe x de la medulla terminalis est present et fonctionnel des le debut du stade embryonnaire metanauplius. La glande du sinus en tant qu'organe neurohemal bien structure est observee pour la premiere fois des l'eclosion. La presence de vesicules d'exocytose des le premier stade larvaire atteste sa fonctionnalite. La synthese, le stockage et la liberation de deux neurohormones, l'hormone hyperglycemiante des crustaces (chh) et l'hormone inhibitrice des gonades (gih), sont demontres des l'eclosion

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5

Guissi, Abderrafie. "Influence des facteurs écologiques sur des populations larvaires de loup "Dicentrarchus labrax" (L. ) et de daurade "Sparus auratus" (Poissons Téléostéens) en élevage intensif". Montpellier 2, 1988. http://www.theses.fr/1988MON20239.

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L'influence de la salinite, de la temperature, du regime alimentaire, de l'intensite lumineuse et de la dimension des bassins d'elevages sur des populations larvaires du loup dicentrarchus labrax elevees dans differentes conditions hydrodynamiques sont etudiees. Ces facteurs manifestent de fortes interactions. L'influence comparative de la salinite sur les larves de loup et de daurade sparus auratus a ete etudiee. Les series experimentales menees a l'echelle pilote sur les larves de loup ont montre que les meilleurs resultats d'elevage sont obtenus dans les lots, eleves en eau courante et en grand bassin, maintenus a une temperature de 16#oc et a une salinite de 10-18& durant les 14 premiers jours et a 22c et 34& ensuite. Ceci a une intensite lumineuse constante des le stade embryonnaire. Une formule alimentaire impliquant des proies peu mobiles et un aliment compose a permis le sevrage des animaux au 20eme jour d'elevage. L'osmoregulation et le mecanisme d'inflation de la vessie natatoire ont ete examines. La dynamique des populations larvaires a ete abordee et un modele bioeconomique de gestion est propose

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6

Réalis-Doyelle, Emilie. "Influence de la température sur les premiers stades de vie de trois espèces de poissons dulcicoles : étude de la survie et de la plasticité phénotypique". Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0272/document.

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D’après le dernier rapport du groupe d'experts intergouvernemental sur l'évolution du climat (GIEC), le réchauffement climatique devrait se poursuivre au cours du siècle prochain. La température atmosphérique moyenne pourrait augmenter de 0,3°C à 4,8°C avec des valeurs extrêmes allant de 1°C à 6°C en 2100. Ces changements de température auront des conséquences directes et indirectes sur l’ensemble de la biodiversité et plus particulièrement sur les poissons qui sont des animaux poïkilothermes. Dans cette étude, trois espèces ont été choisies en prenant en compte leur stratégie de reproduction et leur différence de tolérance thermique : la truite commune (Salmo trutta), le brochet (Esox lucius) et la carpe commune (Cyprinus carpio). Nous avons, pour chacune des trois espèces, appliqué les mêmes différences de température par rapport à leur température de référence (-4, -2, Tref, +2, +4°C) et étudié les effets sur la survie et le développement des embryons et des larves au cours de l’ensemble de la période d’alimentation endogène. Ce travail a confirmé la loi générale de l’impact de la température sur la période d’incubation (Q10 ~3). La truite commune montre une forte diminution de sa survie lors d’une augmentation de quatre degrés, néanmoins les larves survivantes sont plus grandes et ont un contenu énergétique plus important. La survie des larves de brochet augmente avec la température, ces larves sont les plus grandes et leur contenu énergétique est plus important à la température la plus élevée. La survie de la carpe n’est pas affectée par la température ; néanmoins les larves élevées à basse température sont les plus petites et présentent un faible contenu énergétique. Les résultats de survie pour les premiers stades de vie sont en concordance avec les modélisations des aires de répartition actuelle. Dans le futur, la prise en compte de la niche thermique théorique des premiers stades de vie pourrait permettre d’affiner les prévisions des aires de répartition
According to the latest report of the Intergovernmental Panel on Climate Change (IPCC), global warming is expected to continue over the next century, the average temperature could increase by 0.3 ° C to 4.8 ° C with extreme values ranging from 1 ° C to 6 ° C by 2100. These temperature changes will have direct and indirect consequences on the overall biodiversity and specifically fish which are poikilotherms. In this study three species were selected taking into account their reproductive strategy and their thermal tolerance: brown trout (Salmo trutta), pike (Esox lucius) and common carp (Cyprinus carpio). We have applied for all three species the same temperature range of from their referential temperature (-4, -2, Tref °C, +2, + 4 ° C). To carry out this study, we investigated biological traits related to survival and development during the endogenous feeding period. This work confirmed the general law of the impact of temperature during incubation phase (Q10 ~ 3). For brown trout, the results show a collapse of its population with an increase of four degrees; nevertheless surviving larvae were the longest and had a more energetic content. The survival rate of pike larvae increased when temperature increased, these larvae were the longest and the had more energetic content. The survival of the carp was not affected by temperature; nevertheless, at the lowest temperature (16°C), the larvae were smaller and had a lower energetic content. The survival results for the early stages of life are an agreement with the current distribution models. In view of this study the theoretical thermal niche species of early live stage should be undertaken to continue to refine prediction models from range

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7

Xia, Junnan. "The largest subunit of RNA polymerase II (rpb1) as a phylogenetic marker of seed plant species". Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26812.

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The phylogeny of land plants, especially angiosperms, has been perplexing scientists for more than 125 years. The aim of this study was to help elucidate unanswered phylogenetic issues using rpb1 genes from twenty-six land plant species (8 gymnosperm species, 17 angiosperm species and Psilotum, a fernally, as the outgroup). The sixteen rpb1 genes which were sequenced in this study had very similar lengths and contained no base compositional bias. Synonymous substitutions of rpb1 sequences were saturated when compared to the outgroup. The third codon positions of these genes contained misleading phylogenetic information. The topology of trees based on first and second codon positions were in line with that of protein trees. Both angiosperms and gymnosperms were monophyletic. Amborella was found at the base of the angiosperm tree, followed by Nymphae, then Illicium. These data rejected the anthophyte hypothesis, weakly supported the gnepine hypothesis, but did not resolve the interrelationship among eumagnoliids and eudicots. rpb1 genes were combined with the 18S ribosomal RNA gene and chloroplast atpB and rbcL genes to obtain more robust phylogenies. This combined data set produced a topology similar to that of the first and second positions of rpb1 genes except that they better resolved the interrelationship among eumagnoliids and eudicots. We conclude that our rpb1 sequences evolve too slowly to provide enough phylogenetic information to fully resolve the phylogeny of seed plants and that other gene sequences will need to be added to these data sets to obtain a well-resolved phylogenetic tree of seed plants.

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8

Kumlu, Metin. "Physiology of decapod crustacean larvae with special reference to diet". Thesis, Bangor University, 1995. https://research.bangor.ac.uk/portal/en/theses/physiology-of-decapod-crustacean-larvae-with-special-reference-to-diet(d94eed97-fc95-4a40-b6f6-99a809b481a9).html.

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This study investigates the factors affecting larval and postlarval survival and growth of some de capod crustaceans with special emphasis on diets. Investigations were concentrated on the influence o live and artificial diets on larval growth, survival, development and trypsM activity of a cominerciall, important marine penaeid shrimp Penaeus indicus and a freshwater prawn Macrobrachium rosenber gij. In addition, feeding behaviour, gastroevacuation time, trypsM activity of other decapod species wen also studied. Live mixed microalgae Tetraselmis chuii and Skeletonema costatum at 60-70 cells PI-1 promote( highest larval survival, fastest growth and development in P. indicus in comparison to single algal spe cies. Rhinomonas reticulata neither alone nor in combination with other algal species was suitable a! food for the shrimp larvae, A water salinity (S) of 25 ppt was optimal for larval and postlarval cultun of this penaeid species. Postlarvae (PL) of P. indicus reared at lower salinities between PL7 and PL& (20-30 ppt) had a significantly (P<0.05) higher survival and a better growth than those at higher wate salinities. Early PL resisted sudden salinity change of 10 ppt, but required an adaptation period fo greater salinity changes, 10 ppt S was lethal to animals at around PL40-45. A free-living nematode Panagrellus redivivus was found to be a suitable alternative for live algai and Artemia in the culture of P. indicus. The nematodes gave good survival, but lower growth than al gaelArtemia from PZI to PLI. Larval growth and survival were significantly improved when the larvai were fed on either nematodes plus algal co-feeds or liPid-enriched nematodes. Pigmented- (astaxanthin nematodes also improved survival and colour of P. indicus larvae in comparison to non-pigmented ones Conventional live diets were also completely replaced using microencapsulated diets (MED) fo the culture of P. indicus, Like the nematodes, MED as a sole feed resulted In lower survival, slowe growth and development in comparison to algaelArtemia. Addition of 15 cells gl-1 frozen algae signifi cantly improved growth and survival during larval development. The larvae fed MED plus algal co feeds had significantly (P<0.05) higher trypsm activity than those fed MED as a sole feed. Similarly provision of 15 cells gl-' algae with nematodes for only 24h or 48h resulted in significant increase H trypsin activity and improved survival and growth to levels comparable to those obtained from al gaelArtemia. It appears that the presence of an algal diet is necessary to induce larval trypsin activity Mi P. indicus at early protozoeal stages, but algae do not influence trypsin at mysts stages. Results sugges that both nematodes and formulated diets lack gut enzyme stimulants and are less digestible than al gaelArtemia diets. When freeze-dried algal materials were incorporated into MED, it was found tha algal substances which trigger larval digestive enzymes were retained within the capsules. Whether thi will improve growth and survival of penaeid larvae remains to be examined. In contrast to penaeid larvae, a complete replacement of live Artemia with nematodes or artificia diets was not possible for the culture of caridean M rosenbergii and PaIdemon elegans larvae. Fo both species, only a partial replacement was achieved from Z4/5 to metamorphosis by using formulateA diets. It was found that these larvae have very low trypsin activity levels between ZI and Z4/5, but th, levels increase sharply afterwards, coinciding with a vast increase in the hepatopancreas. This sharl increase in digestive enzyme activities and longer food retention time enable these larvae to survive oj less digestible formulated diets. A comparison of specific trypsin activity in several larval decapod crustaceans shows a pattein with high levels in herbivores, low levels in carnivores and intermediate levels M omnivores. Herbivor penaeid larvae (P. indicus) and copepods (Temora longicornis and Centropages typicus) rely on hig digestive enzyme activities to extract nutrients from less digestible algae, whereas carnivorous larvaE the lobsters (Homarus gammarus and Nephrops norvegicus) and carideans (M. rosenbergii and .1 elegans) have limited enzymatic capacity and hence require large and easily digestible prey, but rests long starvation periods. Omnivorous mysis penaeid larvae and Carcinus maenas have intermediat levels of digestive enzymes and are able to transfer from herbivorous to omnivorous feeding. To datE only decapod larvae which show high trypsm activity can be successfidly reared to metamorphosis o: formulated feeds. Inclusion of algal material, as a gut enzyme stimulant, for penaeid protozoeal stage and pre-digested ingredients for later stages into feeds are proposed.

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9

Timmins, William Andrew. "Control of feeding in Manduca sexta larvae". Thesis, University of Bath, 1988. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380387.

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10

Salze, Guillaume Pierre. "Nutritional control of gene expression, larval development and physiology in fish". Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/29655.

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During preliminary research on cobia (Rachycentron canadum, L.) it became increasingly clear that more in-depth information was required to provide enabling techniques for the cobia aquaculture industry to develop more rapidly. A unifying theme in many of the more important issues facing cobia aquaculture is nutrition. This led to nutritional investigations with larval and juvenile fish highlighting the impacts of dietary ingredients on animal performance. Indeed, nutrition can be viewed as a central lever of action through which many aspects of the physiology and the environmental (water) quality of the animal can be controlled. The first project focused on studying the larval development of cobia, a fish species highly suitable for aquaculture for which the industry is nascent. I described the time-course of development of external sensory organs, gut morphology and relevant digestive enzymes under controlled conditions using electron microscopy, histology and spectrophotometric assays. The developmental sequence of larval cobia could be separated in two phases, with a transition period between 12 and 14 days post hatch (dph). This transition is characterized by the formation of the intestinal loop, the establishment of basic cranial neuromast configuration, leading to the initiation of the onset of pancreatic enzymes and the increase of growth rate. In addition, the effects of dietary taurine supplementation and incorporation of mannan oligosaccharides (MOS) into live feeds on cobia larvae development was examined. Fish fed supplementary MOS did not grow faster but displayed higher microvilli length and density. In addition, MOS-fed fish were more resistant to salinity stress. The dietary supplementation of taurine resulted in a dramatic increase in survival, growth and development rates, and enzymatic activities. The second project aimed at refining cobia juvenile nutrition, assessing fish meal and fish oil replacements. Novel sources, including soy protein and oil, were investigated with and without amino acid and MOS supplementations, yielding promising results. Indeed, both fish meal and fish oil were replaced completely and successfully in feeds for juvenile cobia. In addition, novel ingredients (e.g. marine algae meals and soy protein concentrate) were identified to effectively achieve such replacement. The third and last project dealt with nutrient-gene interactions, specifically centering attention on immunostimulants for which the underlying mechanisms of action remain poorly characterized. Here, dietary MOS, nucleotides and selenomethionine (Se-met) were offered to zebrafish whose transcriptome was analyzed by microarray. The immune system, humoral or cellular, innate or adaptive, exhibited different patterns of response according to the immunostimulating nutrient used. In addition, various genes involved in cell cycle and cytokinesis were concomitantly expressed. An intriguing observation related to the insulinomimetic effect of Se-met. In other words, Se-met impacted pathways normally regulated by insulin, such as the MAPK and PI3K pathways. Some Insulin-like Growth Factors (IGF) and IGF bindgin proteins were up-regulated. Additional research is however necessary prior to advocating for the use of these additives, in order to further investigate their respective pros and cons.
Ph. D.

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11

Salley, Sam. "Development of the statocyst of the queen conch larva, Strombus gigas L. (Gastropoda: Prosobranchia)". Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66034.

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12

Rushmore, Margaret E. "Effects of Sedimentation on the Physiology and Oxidative Stress of Two Common Scleractinian Corals". NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/414.

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Abstract (sommario):

This study examined the effect of a growing environmental stressor, sedimentation, on the physiology and oxidative stress throughout the different life stages of two common scleractinian corals Montastraea cavernosa and Porites astreoides. Physiology, oxidative stress, and settlement success of newly released P. astreoides larvae were measured after exposure to various turbidity treatments. No significant effects were seen on larval settlement and photosynthetic efficiency, however carbonyl content and catalase activity were significantly higher in 2015 compared to 2014; highlighting a possible inter-annual variability in susceptibility. Larval settlement deterrence in the presence of a layer of accumulated fine- or coarse-grained sediment was examined and showed significant differences between treatments but not between sediment grain sizes. Ultimately showing that any sediment can deter settlement. The deleterious effects of sediment accumulation on the survival of newly settled spat was examined by smothering with varying layers of fine- or coarse- grained sediment. Survival was significantly different by treatment with coarse-grained sediment showing decreased survival with increasing accumulation. In adult P. astreoides fragments photosynthetic efficiency significantly decreased after being exposed to layers of accumulated sediment, with recovery monitoring after exposure revealing that over time photosynthetic efficiency did not recover to pre-exposure levels. However, in M. cavernosa the photosynthetic efficiency of fragments exposed to high sedimentation saw significant recovery after exposure. Significant differences among oxidative stress biomarkers (catalase activity and carbonyl content) were seen among exposed P. astreoides fragments, however no significance was seen in M. cavernosa. Tissue mortality was also assessed with P. astreoides fragments having significantly higher mortality compared to M. cavernosa. These results highlight the negative effects of sedimentation on scleractinian corals throughout their life history stages, increasing our need for a more thorough understanding of this growing environmental stressor.

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13

Ho, Dao H. "Morphological and physiological developmental consequences of parental effects in the chicken embryo (Gallus gallus domesticus) and the zebrafish larva (Danio rerio)". Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc9086/.

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Cardiac, metabolic and growth response of early-stage chicken embryos to perturbations in yolk environment was investigated. Also, effects of parental hypoxia exposure on hypoxia resistance, thermal tolerance and body length of zebrafish larvae were investigated. In the first study, thyroxine, triiodothyronine and testosterone produced differential effects on heart rate and development rate of chicken embryos during the first 4 days of development. Triiodothyronine caused a dose-dependent increase in heart rate when applied at 40 or 70 hours of age, while thyroxine caused a dose-dependent increase in heart rate when applied at 40 hours only. Testosterone and propyl-thiouracil (deiodinase antagonist) did not have an effect on heart rate. Development rate was not changed by thyroxine, triiodothyronine, testosterone or propyl-thiouracil, which suggested that heart rate changes did not result from changes in embryo maturity. In the second study, chicken embryos exposed to yolks of different bird species during early-stage embryonic development showed changes in heart rate, mass-specific oxygen consumption and body mass that scaled with the egg mass, incubation period length, and yolk triiodothyronine and testosterone levels of the species from which yolk was derived. In the third study, this phenomenon was investigated between layer and broiler chickens. Heart rate, oxygen consumption and body mass of broiler and layer embryos were significantly changed by a breed-specific change in yolk environment. Yolk triiodothyronine and testosterone concentrations of broiler and layer eggs did not suggest that these hormones were responsible for physiological and morphological changes observed. The final study demonstrated that hypoxia resistance and body lengths, but not thermal tolerance of zebrafish larvae was increased by parental hypoxia exposure.

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14

Chast, François. "Etude biopharmaceutique du système naso-lacrymal au moyen de l'administration ophtalmique et nasale de morphine". Paris 5, 1991. http://www.theses.fr/1991PA05P606.

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15

Ng, Karen Karpui. "Malpighian tubules of A. dorsalis mosquito larvae : general characteristics and mechanism of magnesium transport". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24873.

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Abstract (sommario):

Malpighian tubules of A. dorsalis mosquito larvae, studied in vitro, actively transported magnesium at high rates against concentration gradients as large as 16-fold and transepithelial potential gradients of approximately -l5mV. Fluid secretion rates, determined over 90 minute periods, in the presence and absence of cAMP, indicated that A. dorsalis tubules were viable and had secretion rates of the same magnitude as those reported for A. taeniorhynchus tubules. Having characterized the in vitro preparation of Malpighian tubules, the main hypothesis that Mg²⁺ transport is driven predominately by counter transport with Na⁺ was tested. This hypothesis was not supported by kinetic, Na-substitution, or inhibitor studies. Kinetic and Bumetanide studies suggest backflux of K drives J mg; however, this was not consistently found in other studies.
Science, Faculty of
Zoology, Department of
Graduate

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16

Thompson, Ernst Frederick. "Towards the development of a larval feeding strategy for the white-margined sole (Dagetichthys marginatus)". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1012982.

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Abstract (sommario):

The major bottleneck during the domestication of the white-margined sole Dagetichthys marginatus in South Africa has been low larval survival. The cause of this is not clear but considering current literature on flatfish culture and more specifically soleid culture, nutritional deficiencies are hypothesized to be the main possible cause. Following the importance of nutrition, the first aim of the research was to use an ontogenetic developmental approach to develop a species specific larval feeding strategy. Ontogenetic development of D. marginatus showed that weaning will take place at much later ages than other soleids currently being farmed. This makes the partial replacement of Artemia with a suitable inert diet in co-feeding strategies very important to cut the cost associated of live food production. This leads on to the second aim, in which an 'in vitro' approach was used to model the digestibility of Artemia, which could ultimately contribute towards designing inert feeds with similar digestibility characteristics to Artemia in the future. Obtaining nutrients from food is closely linked to the functional status of the digestive tract, the support organs and the external morphological characteristics required for the ingestion of live or inert feeds. Considering both morphological and physiological ontogenetic development, it is clear that D. marginatus follow a similar pattern to other soleids. Larvae can successfully feed on Artemia as early as 3 days after hatching but exhibit a slow metamorphosis into the juvenile stage when compared to other soleids. The absence of any detectable acidic protease activity during the first 45 days of development and the importance of exogenous enzymes from Artemia all points to limited capacity to digest artificial diets. Prior to modelling the 'in vitro' digestion of Artemia, digestive enzyme activity at different pH's were modelled using functional forms from the normal distributive category of functions.
As there is no substantiated information for the general effects of pH on enzyme activity in the literature for finfish larvae, three species occurring in the same bio-geographical region of Dagetichthys marginatus, namely Sarpa salpa, Diplodus sargus capensis and Argyrosomus japonicus were used to investigate this effect. The fitted parameters, namely the optimal pH and sigma (the slope around the optimal pH) showed two interesting results. When using a negative log likelihood ratio test to test for differences between species for a particular enzyme, the optimal pH for alkaline proteases (7.67), lipase (8.03), amylase (7.69) and phosphatase (9.84) activity was the same for all three species. Furthermore, the study illustrated the potential to detect dietary shifts during ontogenetic development based on changes in enzyme activity around the optimal pH using the sigma parameter. Sarpa salpa showed increased amylase activity and a decrease in protease activity around the optimal pH with increased size, corresponding to a change in diet from zooplankton to algae. The 'in vitro' modelling approach taken in this study was based on known enzyme interactions and dynamics which makes the results very interpretable. from Artemia is achieved based on gut evacuation time and enzyme levels. This 'in vitro' study furthermore clearly indicates the importance of exogenous enzymes from Artemia, contributing as much as 54 percent to protein digestion and 64 – 72 percent to carbohydrate digestion. This was however, only an initial investigation, and further expansion of the model is required to achieve a complete understanding of Artemia digestion and ultimately partial replacement with artificial diets. A feeding strategy for D. marginatus should therefore follow those of other farmed soleids, although there will be a general delay in implementation due to slower development. Problems can thus be solved and improvements made by transferring technology from other soleids to D. marginatus.

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17

Palenske, Nicole Marie. "Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae". Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc11016/.

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Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in chronic heart rate were dependent upon stage of development and exposure concentration. This research indicates that the toxicity of amphibian larvae exposed to triclosan, triclocarban, and caffeine appears to be dependent upon species and developmental stage, with early developmental stages being most sensitive to contaminant exposure.

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Johnston, Matthew D. "Feeding and digestion in the phyllosoma larvae of ornate spiny lobster, Panulirus ornatus (Fabricius) and the implications for their culture". University of Western Australia. School of Animal Biology, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0150.

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[Truncated abstract] In this thesis I investigated the ingestive and digestive morphology and digestive physiology during development of phyllosomata of the ornate spiny lobster, Panulirus ornatus. This knowledge was applied to develop a suitable formulated diet to be fed in combination with Artemia or used as a supplement to reduce production costs. The major impediment to closure of the life cycle of spiny lobsters has been an inadequate dietary regime, stemming from a lack of information on their feeding biology and ingestive and digestive capabilities. Of all spiny lobster species, P. ornatus is the best candidate for aquaculture in Australia having the shortest larval development phase (46 months) and fast growth rate, attaining 1 kg within 2 years of hatch. Currently, Artemia and fresh feeds such as mussel are used routinely as hatchery feeds. However, the development of a formulated diet that is palatable and delivers the correct balance of nutrients is seen as a highly attractive and cost effective alternative. An appropriate formulated diet for aquaculture of phyllosomata of spiny lobsters can be developed more effectively when the ingestive and digestive morphology, physiology and feeding behaviour are fully understood. ... Partial replacement trials revealed that P. ornatus phyllosoma are stimulated to feed by visual cues. Furthermore, 75% of the entire Artemia ration can be replaced with a formulated diet without having any adverse effects on survival and growth of early-stage phyllosomata. Weaning P. ornatus phyllosomata onto 100% formulated diet during stages II-III resulted in reduced survival but demonstrated that diets containing 44-50% crude protein with a diverse range of marine protein sources provides optimum survival and growth. This thesis has identified both physical and nutritional components that will contribute to the successful development of formulated diets for aquaculture of this species. Ultimately, although formulated diets are ingested and provide more than adequate survival when fed in combination with Artemia during early ontogeny, greater success and the possibility of totally replacing Artemia may occur after day 32 (stage IV) due to an increased efficiency to capture and manipulate larger sized particles externally and a greater capacity to triturate prey and sort and filter particles internally. Furthermore, a general increase in specific activity of digestive enzymes at stage IV suggests the possibility of a greater capacity to digest and assimilate nutrients.

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19

Gore, Matthew R. "Influence of parental swimming stamina on the cardiac and metabolic performance of larval zebrafish (Danio rerio)". Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3669/.

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Superior swimming stamina in adult fish is presumably passed on to their offspring, but the ontogeny of the appearance of superior stamina and the requisite enhanced cardio-respiratory support for locomotion in larval fishes has not been determined. Is the expression of the suite of parental traits enabling superior swimming stamina in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in their larvae? To answer this, adults were classified into three groups based on swimming stamina, followed by measurement of length, mass, and width. Larval offspring from the two parental groups -high stamina larvae (HSL) and low stamina larvae (LSL)- were reared at 27°C in aerated water (21% O2). Routine and active heart rate, routine and active mass specific oxygen consumption were recorded through 21dpf, and cost of transport (COT) and factorial aerobic scope were derived from oxygen consumption measurements. Routine heart rate at 2dpf of LSL was 164 ± 1 b·min-1, compared to only 125 ± 2 b·min-1 for HSL. Routine heart rate subsequently peaked at 203 ± 1 b·min-1 at 5dpf in the HSL group, compared to 207 ± 1 b·min-1, at 4dpf in the LSP larvae. Active heart rate at 5 dpf of LSL was 218 ± 2 b·min-1 compared to 216 ± 2 b·min-1 for HSL. Active heart rate increased slightly to 227 ± 2 b·min-1 for LSL before decreasing again, while active heart rate remained relatively constant for HSL. Routine O2 consumption at 2dpf of HSL was 0.09 μmol·mg-1·hr-1, compared to 0.03 μmol·mg-1·hr-1 in LSL. Routine O2 consumption subsequently peaked at 0.70 μmol·mg-1·hr-1 at 9dpf in the HSL, compared to 0.71 μmol·mg-1·hr-1, at 9dpf in the LSL. These values dramatically decreased before leveling off at around 0.20 μmol·mg-1·hr-1 and 0.15 μmol·mg-1·h-1, respectively. Active O2 consumption at 5dpf for HSL was 0.38 μmol·mg-1·hr-1, compared to 0.57 μmol·mg-1·hr-1 for LSL. Active O2 consumption subsequently peaked at 0.97 μmol·mg-1·hr-1 at 10dpf in HSL, compared to 1.19 μmol·mg-1·hr-1 at 7dpf in LSL. These values also dramatically decreased and leveled off. Significant differences (p < 0.05) in heart rate and oxygen consumption persisted through 21dpf. The onset of differences observed in routine and active heart rate in early larvae, correlated with parent stamina, show that juvenile or adult features are not required as a precondition for the emergence of phenotypic physiological differences.

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20

Terras, Fériel. "Développement d’une méthode de mesure et d’analyse du transport intraneuronal dans le cerveau de larve de poissons-zèbre par suivi de nanocristaux non-linéaires en microscopie de second-harmonique : application à l’étude d’anomalies de transport chez des poissons portant une mutation retrouvée dans des neuropathies humaines". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASP050.

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Le transport moléculaire dans les neurones joue un rôle essentiel dans leur développement et la maintenance de leurs fonctions, en raison notamment de leurs longues arborescences. Les conséquences d’anomalies du transport axonal ont été associées de longue date à la maladie d’Alzheimer telle que le gonflement des axones consécutif à l’accumulation des organelles transportés, mais il y a peu d’outils permettant l’étude fine sur le long terme de ce transport en culture et encore moins in vivo.L’équipe dans laquelle cette thèse a été réalisée a développé une méthode de mesure du transport intraneuronal en culture de neurone de souris reposant sur le suivi d’endosomes ayant internalisé spontanément des nanodiamants fluorescents. Elle a également démontré la grande sensibilité de cette méthode à détecter des facteurs de risques génétiques de maladies neuropsychiatriques.L’objectif de ma thèse a été d’étendre cette méthode de mesure au circuit neuronal intègre du cerveau de larves de poisson zèbre. Pour ce faire j’ai utilisé des nanocristaux (NCs) à réponse optique non-linéaires, pouvant être excité dans une fenêtre de transparence des tissus, à une longueur d’onde ≈1 µm, et générant un signal de second harmonique (SHG). Nous avons utilisé le microscope multiphoton de la plateforme Emerg’In (INRAE, Jouy-en-Josas) qui est installée au sein d’une pisciculture et dispose de scanners galvanométriques résonants et de détecteurs hybrides, ce qui nous a permis de maintenir une cadence de 20 champs par seconde malgré la nécessité de balayer le faisceau laser, contrairement aux études en culture, menées en champ large.Nous avons mis au point un nouveau protocole de mesure, depuis l’injection des NC jusqu’à l’extraction des paramètres de transport à partir des données vidéos. Pour cela, j’ai optimisé et automatisé les analyses des données en développant deux programmes écrits en Python : l’un permettant de reconstruire automatiquement les trajectoires des NCs de manière la plus fidèle possible et l’autre permettant de segmenter les trajectoires en phases de mouvement et de pauses afin d’en extraire des paramètres de transport.J’ai appliqué ces nouveaux outils à l’étude, sur un modèle transgénique de poisson zèbre, de l’impact fonctionnel d’une mutation présente dans des neuropathies dont une paraplégie spastique héréditaire et la maladie de Charcot-Marie-Tooth périphérique. Chez des patients atteints par l’une de ces maladies, plusieurs mutations ont été identifiées sur le gène KIF5A codant pour la chaine lourde du moteur moléculaire kinésine 1 qui assure des déplacements antérogrades (du corps cellulaire vers la périphérie). Nous avons mesuré le transport d’endosomes dans les axones de neurones du cerveau de larve de poissons zèbres transgéniques portant une mutation sur kif5a, et avons observé des modifications subtiles de ce transport. Pour cela, plus de 500 trajectoires d’endosomes (acquises à une profondeur de ≈100 µm sous la surface de la tête) ont été analysées, issues de 40 larves.En guise de contrôle, nous avons également étudié le transport endosomal dans des mutants privés des moteurs dynéines, les seuls à assurer le transport rétrograde, et avons observé que le transport bidirectionnel était totalement arrêté dans les mutants.La méthodologie mise en place peut servir à cribler des anomalies fonctionnelles résultant de facteurs génétiques de troubles neurologiques ou neurodégénératifs
Molecular transport in neurons plays an essential role in their development and the maintenance of their functions, due in particular to their long branches. The consequences of axonal transport abnormalities have long been associated with Alzheimer's disease, such as the swelling of axons caused by the accumulation of transported organelles. However, there are few tools allowing the detailed long-term study of this transport in culture and even less in vivo.The team in which this work was conducted has developed a method for measuring intraneuronal transport in mouse cultured neurons based on the tracking of endosomes having spontaneously internalized fluorescent nanodiamonds. This technique was able to detect genetic risk factors of neuropsychiatric diseases, proving its high sensitivity.The objective of my thesis was to extend this measurement method to the neuronal circuit of the zebrafish larvae’s brain. For this purpose, I have used nanocrystals (NCs) with non-linear optical response, which can be excited in a tissue transparency window at a wavelength ≈1 µm, and generate a second harmonic signal. We have used the multiphoton microscope of the Emerg'In facility (INRAE, Jouy-en-Josas), which is installed next to a fish farming and has resonant galvanometric scanners and hybrid detectors, which allowed us to maintain a frame rate of 20 fps despite the need to scan the laser beam, unlike in culture studies conducted in wide field.We have developed a new measurement protocol, from the injection of the NC to the extraction of transport parameters from the videos data. To do this, I have optimized and automated the data analysis by developing two programs written in Python: one that automatically reconstructs the trajectories of the NCs as faithfully as possible and the other that segments the trajectories into motion and pause phases in order to extract transport parameters.I have applied these new tools to study, in a transgenic zebrafish model, the functional impact of a mutation present in neuropathies including hereditary spastic paraplegia and peripheral Charcot-Marie-Tooth disease. In patients suffering from one of these diseases, several mutations have been identified in the KIF5A gene coding for the heavy chain of the kinesin 1 molecular motor which ensures anterograde movements (from the cell body to the periphery). We have measured endosome transport in axons of neurons in the brain of transgenic zebrafish larvae bearing a mutation on kif5a, and we observed subtle changes in this transport. More than 500 endosome trajectories (acquired at a depth of ≈100 µm below the surface of the head) were analyzed from 40 larvae.As a control, we also studied endosomal transport in mutants deprived of dynein motors, the only ones to ensure retrograde transport, and observed that bi-directional transport was totally stopped in the mutants.This methodology can be used to screen for functional abnormalities resulting from genetic factors of neurological or neurodegenerative disorders

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Ajibewa, Tiwaloluwa Adedamola. "Role of anxiety on vascular dysfunction". Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3035.

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High anxiety is associated with an increased risk of developing cardiovascular disease (CVD), in particular, atherosclerotic coronary artery disease. However, the mechanisms by which anxiety contributes to the development of CVD are unclear. Unlike other common psychiatric disorders such as depression, anxiety and its effects on CVD risk has not been studied extensively. Moreover, whether elevated anxiety is associated with arterial stiffness and vascular endothelial dysfunction, biomarkers of CVD risk, in healthy adults and whether a psychological intervention designed to lower anxiety levels in healthy adults with moderate to high baseline anxiety levels ameliorates vascular dysfunction remains unclear. The purpose of this study was twofold; first to determine the extent to which moderate to high anxiety levels are associated with vascular dysfunction including aortic stiffness as measured by carotid-femoral pulse wave velocity (cf-PWV), carotid artery stiffness via ultrasound-based β-stiffness index, and forearm resistance artery function measured as peak forearm blood flow using venous occlusion plethysmograph (VOP). Secondly, to determine whether the empirically validated Acceptance and Commitment Training (ACT) anxiety intervention improved vascular function after 12 weeks and if this was associated with reductions in anxiety in adults with moderate to high baseline anxiety levels. Our results indicated that there was no association between increased anxiety levels and any of the three vascular outcomes of interest. Conversely, there was an association between the ACT intervention participation and improvement in forearm resistance artery function independent of age, sex, education, race/ethnicity, BMI and STAI Trait anxiety. Taken together, these data suggest that although higher State and Trait anxiety was not associated with aortic stiffness, carotid stiffness or forearm resistance artery function, and the ACT intervention was associated with improved peripheral resistance artery function. Additional studies are needed to determine whether this effect occurs earlier than 12 weeks and sustained longer that 12 weeks, and whether it occurs in adults with CVD risk factors (i.e. atherosclerosis), non-white racial/ethnic backgrounds and in resistance vessel function in response to intra-arterial vasoactive agonists such as acetylcholine.

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22

Freitas, Daniela Reis Joaquim de. "Caracterização de resposta a estresse oxidativo e mecanismos de morte celular em Boophilus microplus". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/8336.

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O carrapato bovino Boophilus microplus está presente em áreas tropicais e subtropicais no mundo e é um ectoparasito hematófago que causa inúmeras perdas à bovinocultura, através da espoliação ao bovino ou das doenças que transmite como vetor. Atualmente, o principal método de controle empregado baseia-se em produtos químicos, que são onerosos e contaminam o ambiente. Estudos a respeito da ecologia, comportamento e fisiologia de B. microplus são importantes para o desenvolvimento de novos métodos de controle do carrapato. A resposta ao estresse oxidadivo e a morte celular programada, examinadas neste estudo, permitem compreender melhor os mecanismos fisiológicos usados pelo carrapato adulto e seus ovos e larvas para sobreviver no ambiente. A resposta a estresse oxidativo foi analisada em ovos e larvas. A atividade de GST e outras moléculas envolvidas em mecanismos de proteção contra estresse oxidativo variaram dependendo do tempo transcorrido após a postura e eclosão. A cinética do consumo de oxigênio apresentou correlação positiva com o aumento na atividade de GST durante a embriogênese. Um alto conteúdo de substâncias reativas ao ácido tiobarbitúrico foi observado em extratos de ovos e larvas, indicando que carrapatos apresentam alto estresse oxidativo durante a embriogênese e desenvolvimento larval. Além disso, a atividade de GST apresentou forte correlação com peroxidação de lipídeos, uma indicação de seu papel na defesa antioxidante em ovos. Com o objetivo de melhor caracterizar o processo de morte celular, que elimina tecidos não mais necessários e leva à degeneração de glândulas salivares, ovários e singânglios, foi feita uma investigação usando ensaios de visualização de fragmentação de DNA em gel de agarose, teste cometa e TUNEL e a ativação da via apoptótica foi analisada usando ensaio de caspase. A fragmentação de DNA e a atividade enzimática de caspase-3 foram observadas em glândulas salivares e ovários 48 e 72 h após a remoção do carrapato do hospedeiro; em singânglios estes parâmetros foram mantidos em baixos níveis após 48 h. Estes resultados obtidos sugerem que há um controle refinado de manutenção de tecido através de apoptose.
The cattle tick Boophilus microplus is present in tropical and subtropical areas in the world and it is a haematophagous ectoparasite that causes several losses to cattle breeding, through the bovine exploiting and diseases transmitted. Currently, the main control method is based on chemicals, which are expensive and contaminate the environment. Studies about ecology, behavior and physiology of B. microplus are important to develop new methods for the tick control. The data examined in this study allow understanding the physiologic mechanisms used by the tick, eggs and larvae to survive in the environment. For this, the oxidative stress response in eggs and larvae and the cell death in different tissues of adult tick females during the pre-oviposition period were analyzed. The oxidative stress response was analyzed in eggs and larvae and the results showed that the GST activity and other molecules involved in mechanism of protection against oxidative stress varied depending on the time elapsed after oviposition and eclosion. A positive correlation was observed between the oxygen consumption kinetics and the increase in GST activity during embryogenesis. A high content of thiobarbituric acid reactive substances were observed in egg and larva extracts, indicating that ticks face high oxidative stress during embryogenesis and aging. In addition, GST activity presented strong positive correlation with lipid peroxidation, an indication that it plays a role in oxidant defences in eggs. In order to better characterize the cell death process that eliminates unnecessary tissues, the degeneration of salivary glands, ovaries and synganglia was investigated using DNA fragmentation in agarose gel, comet and TUNEL assays, and apoptosis activation pathway by the caspase assay. DNA fragmentation and enzymatic activity of caspase-3 were observed in salivary glands and ovaries at 48 and 72 h after tick removal from the host; in synganglia these parameters were maintained at low levels upon 48 h. These results obtained suggest that there is a refined control of tissue maintenance through apoptosis.

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23

Signor, Altevir [UNESP]. "Levedura íntegra e leverura autolisada como pronutriente em dieta para reprodutores de Tílápia do Nilo (Oreochromis niloticus)". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/104127.

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Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-27Bitstream added on 2014-06-13T21:05:27Z : No. of bitstreams: 1 signor_a_dr_botfmvz.pdf: 560532 bytes, checksum: 83329148a6a5185429d5e4c31d176bfc (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Universidade Estadual Paulista (UNESP)
A composição nutricional da levedura a destaca como alimento funcional. O presente trabalho objetivou avaliar a ação da levedura (Saccharomyces cerevisiae) nas respostas reprodutivas de fêmeas de tilápia do Nilo. No Estudo-I 105 fêmeas da linhagem GIFT foram distribuídas em 15 aquários de 500L (três tratamentos e cinco repetições com sete peixes/aquário). No Estudo-II foram utilizados 63 fêmeas e 21 machos da linhagem GIFT distribuídos em três aquários com capacidade de 7000L de água/cada (21 fêmeas e sete machos/aquário). Em ambos os Estudos, os reprodutores foram alimentados ad libitum com dietas isoprotéica e isoenergética contendo 2,0% de levedura íntegra, 2,0% de levedura autolisada ou ausente de inclusão. O Estudo-I foi realizado na UNESP – AquaNutri, Campus de Botucatu e o Estudo-II foi conduzido no Caunesp - Tilapilcultura Campus de Jaboticabal. Avaliou-se nas fêmeas o desempenho produtivo, status nutricional e composição química das gônadas e, o desempenho reprodutivo e o desenvolvimento inicial das larvas. Os dados foram submetidos à análise de variância e quando significativo aplicou-se o teste de comparações múltiplas de médias. A suplementação de levedura íntegra ou autolisada na dieta das reprodutoras, não melhorou o desempenho produtivo e não influenciou o desempenho reprodutivo das fêmeas. Entretanto, melhorou o desenvolvimento larval 72h após eclosão, com melhor desenvolvimento nas larvas dos reprodutores alimentados com a dieta suplementada com 2,0% de levedura íntegra.
The nutritional composition yeast detach how functional food. The research present objective evaluates the action yeast (Saccharomyces cerevisiae) in the response reproductive of females of Nile tilapia. In Study-I 105 females of GIFT lineage was randomized in 15 500L-aquarius (three treatments and five repetition with seven fish/aquarium). In Study-II was utilized 63 females and 21 males of GIFT lineage was randomized in three 7000L-aquarium (21 female and seven male for aquarium). The spawning was feed ad libitum with diet isoproteic and isoenergetic with 2,0% whole yeast and autolised yeast or supplementation absent. In Study-I were realize in UNESP – AquaNutri Campus de Botucatu and Study-II in Caunesp – Tilapicultura Campus de Jaboticabal. Was evaluation in female productive performance, nutritional status and chemistry composition of gonad (Study-I) and reproductive performance of spawning and development larvae (Study-II). The data was submitted variance analyses and multiple comparison test of mean. The supplemented whole yeast or autolised yeast in diet of spawning didn’t improvement productive performance and didn’t influence reproductive performance of female. Therefore improved of development larvae at 72h after eclosion with improved development in larvae of spawning feed with diet 2,0% whole yeast.

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24

Signor, Altevir 1976. "Levedura íntegra e leverura autolisada como pronutriente em dieta para reprodutores de Tílápia do Nilo (Oreochromis niloticus) /". Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/104127.

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Resumo: A composição nutricional da levedura a destaca como alimento funcional. O presente trabalho objetivou avaliar a ação da levedura (Saccharomyces cerevisiae) nas respostas reprodutivas de fêmeas de tilápia do Nilo. No Estudo-I 105 fêmeas da linhagem GIFT foram distribuídas em 15 aquários de 500L (três tratamentos e cinco repetições com sete peixes/aquário). No Estudo-II foram utilizados 63 fêmeas e 21 machos da linhagem GIFT distribuídos em três aquários com capacidade de 7000L de água/cada (21 fêmeas e sete machos/aquário). Em ambos os Estudos, os reprodutores foram alimentados ad libitum com dietas isoprotéica e isoenergética contendo 2,0% de levedura íntegra, 2,0% de levedura autolisada ou ausente de inclusão. O Estudo-I foi realizado na UNESP - AquaNutri, Campus de Botucatu e o Estudo-II foi conduzido no Caunesp - Tilapilcultura Campus de Jaboticabal. Avaliou-se nas fêmeas o desempenho produtivo, status nutricional e composição química das gônadas e, o desempenho reprodutivo e o desenvolvimento inicial das larvas. Os dados foram submetidos à análise de variância e quando significativo aplicou-se o teste de comparações múltiplas de médias. A suplementação de levedura íntegra ou autolisada na dieta das reprodutoras, não melhorou o desempenho produtivo e não influenciou o desempenho reprodutivo das fêmeas. Entretanto, melhorou o desenvolvimento larval 72h após eclosão, com melhor desenvolvimento nas larvas dos reprodutores alimentados com a dieta suplementada com 2,0% de levedura íntegra.
Abstract: The nutritional composition yeast detach how functional food. The research present objective evaluates the action yeast (Saccharomyces cerevisiae) in the response reproductive of females of Nile tilapia. In Study-I 105 females of GIFT lineage was randomized in 15 500L-aquarius (three treatments and five repetition with seven fish/aquarium). In Study-II was utilized 63 females and 21 males of GIFT lineage was randomized in three 7000L-aquarium (21 female and seven male for aquarium). The spawning was feed ad libitum with diet isoproteic and isoenergetic with 2,0% whole yeast and autolised yeast or supplementation absent. In Study-I were realize in UNESP - AquaNutri Campus de Botucatu and Study-II in Caunesp - Tilapicultura Campus de Jaboticabal. Was evaluation in female productive performance, nutritional status and chemistry composition of gonad (Study-I) and reproductive performance of spawning and development larvae (Study-II). The data was submitted variance analyses and multiple comparison test of mean. The supplemented whole yeast or autolised yeast in diet of spawning didn't improvement productive performance and didn't influence reproductive performance of female. Therefore improved of development larvae at 72h after eclosion with improved development in larvae of spawning feed with diet 2,0% whole yeast.
Orientador: Luiz Edivaldo Pezzato
Coorientador: Margarida Maria Barros
Coorientador: Teresa Cristina Dias Ribeiro Koberstein
Doutor

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Roth, Emily Nicole. "An Investigation of the Influence of Students’ Academic Year, Students’ Declared Major, and Quiz Format on Academic Achievement in a Large Enrollment Undergraduate Human Gross Anatomy Course". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429870248.

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26

Sanz, Leon Paula. "Development of a computational and neuroinformatics framework for large-scale brain modelling". Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5036/document.

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Abstract (sommario):

The central theme of this thesis is the development of both a generalised computational model for large-scale brain networks and the neuroinformatics platform that enables a systematic exploration and analysis of those models. In this thesis we describe the mathematical framework of the computational model at the core of the tool The Virtual brain (TVB), designed to recreate collective whole brain dynamics by virtualising brain structure and function, allowing simultaneous outputs of a number of experimental modalities such as electro- and magnetoencephalography (EEG, MEG) and functional Magnetic Resonance Imaging (fMRI). The implementation allows for a systematic exploration and manipulation of every underlying component of a large-scale brain network model (BNM), such as the neural mass model governing the local dynamics or the structural connectivity constraining the space time structure of the network couplings. We also review previous studies related to brain network models and multimodal neuroimaging integration and detail how they are related to the general model presented in this work. Practical examples describing how to build a minimal *in silico* primate brain model are given. Finally, we explain how the resulting software tool, TVB, facilitates the collaboration between experimentalists and modellers by exposing both a comprehensive simulator for brain dynamics and an integrative framework for the management, analysis, and simulation of structural and functional data in an accessible, web-based interface
The central theme of this thesis is the development of both a generalised computational model for large-scale brain networks and the neuroinformatics platform that enables a systematic exploration and analysis of those models. In this thesis we describe the mathematical framework of the computational model at the core of the tool The Virtual brain (TVB), designed to recreate collective whole brain dynamics by virtualising brain structure and function, allowing simultaneous outputs of a number of experimental modalities such as electro- and magnetoencephalography (EEG, MEG) and functional Magnetic Resonance Imaging (fMRI). The implementation allows for a systematic exploration and manipulation of every underlying component of a large-scale brain network model (BNM), such as the neural mass model governing the local dynamics or the structural connectivity constraining the space time structure of the network couplings. We also review previous studies related to brain network models and multimodal neuroimaging integration and detail how they are related to the general model presented in this work. Practical examples describing how to build a minimal *in silico* primate brain model are given. Finally, we explain how the resulting software tool, TVB, facilitates the collaboration between experimentalists and modellers by exposing both a comprehensive simulator for brain dynamics and an integrative framework for the management, analysis, and simulation of structural and functional data in an accessible, web-based interface

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27

Adam, Emma N. "DIFFERENTIAL GENE EXPRESSION IN EQUINE CARTILAGINOUS TISSUES AND INDUCED CHONDROCYTES". UKnowledge, 2016. http://uknowledge.uky.edu/gluck_etds/25.

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Degenerative joint disease, or osteoarthritis, is a major cause of lameness and morbidity in horses, humans, and dogs. There are no truly satisfactory cures for this widespread problem and current treatments all have limitations or unwanted side effects. New cell-based strategies to repair joint surface lesions have generated a high level of interest, but have yet to achieve the full restoration of articular cartilage structure and function. Currently used therapy cells include autologous chondrocytes and adult mesenchymal cells such as bone marrow derived cells and adipose derived cells. Unfortunately, the resultant repair tissue is biomechanically inferior fibrocartilage. A critical gap in knowledge in this regard is a limited understanding of the specific cellular phenotype of normal, robust articular chondrocytes. This thesis examines the global mRNA transcriptome of equine articular cartilage to test the hypothesis that adult articular chondrocytes have a unique gene expression profile. In the first part of the study, RNA-sequencing was used to compare the mRNA transcriptome of normal adult articular cartilage with five other cartilaginous tissues. From these comparisons, locus level gene expression and alternative splicing patterns have been identified that clearly distinguish articular cartilage. In the second part of the study, fetal (interzone, cartilage anlagen chondrocytes, dermal fibroblasts) and adult (bone marrow derived, adipose derived, articular chondrocytes, dermal fibroblasts) primary cells were grown in culture and stimulated to differentiate into chondrocytes. The chondrogenic differentiation potential as assessed by matrix proteoglycan and the expression of cartilage biomarker genes was highly variable among cell types. Together, these results advance our understanding of the specific phenotype of articular chondrocytes and the potential of prospective therapeutic progenitor cells to differentiate into articular chondrocytes. This new knowledge will improve efforts to optimize cell-based therapies for osteoarthritis and the repair of joint cartilage lesions.

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28

Fedorka, Carleigh Elizabeth. "AN INVESTIGATION INTO SPECIFIC SEMINAL PLASMA PROTEINS AND THEIR EFFECT ON THE INNATE IMMUNE RESPONSE TO BREEDING IN THE MARE". UKnowledge, 2017. http://uknowledge.uky.edu/gluck_etds/29.

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The mare experiences a transient innate immune response to breeding, the resolution of which is crucial for optimal fertility. The majority of mares are able to modulate this inflammation in a timely fashion, but a subpopulation exists which fail to do so and are considered susceptible to persistent breeding-induced endometritis (PBIE). Seminal plasma has been shown to modulate aspects of this inflammation. Recently, two seminal plasma proteins have garnered interest for their immune modulating properties: cysteine-rich secretory protein-3 (CRISP-3) and lactoferrin. These proteins have been found to alter the binding between sperm and neutrophils based on sperm viability in vitro, but minimal work has evaluated their effect on endometrial mRNA expression of cytokines and inflammation in response to breeding. Experiments were performed to analyze the expression of equine CRISP-3. Found to be primarily synthesized in the ampulla of the vas deferens and to a lesser extent in the vesicular gland, CRISP-3 expression was only seen in the postpubertal stallion. Due to the effect of sperm viability on protein function in vitro, varying sperm populations were analyzed for their effect on gene expression in the uterus. It was determined that viable sperm suppressed the gene expression of the inflammatory modulating cytokine interleukin-6 (IL-6) in comparison to dead sperm. Next, the effect of CRISP-3 and lactoferrin on endometrial gene expression in the normal and susceptible mare was investigated. Neither protein had a significant effect on the mRNA expression of inflammatory cytokines in the normal mares at six hours post-breeding. In contrast, lactoferrin was found to significantly suppress the expression of the pro-inflammatory cytokine tumor necrosis factor (TNF)-α in susceptible mares. Due to this, lactoferrin was further analyzed as an immunomodulant for the treatment of PBIE. Susceptible mares were infused with varying doses of lactoferrin at six hours post-breeding. Although not in a dose-dependent fashion, lactoferrin was found to decrease both fluid retention and neutrophil migration, in addition to suppressing the expression of the pro-inflammatory cytokine interferon gamma (IFNγ) and increasing the gene expression of the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1RN). In conclusion, CRISP-3 expression occurs in secretory aspects of the male reproductive tract, and appears to be up regulated after sexual maturation. Viability of spermatozoa affects the immune response to breeding and should be taken into consideration for experimental design and interpretation of data. The seminal plasma proteins CRISP-3 and lactoferrin have minimal effect on endometrial gene expression in normal mares, but lactoferrin suppresses the expression of TNF in susceptible mares. Finally, lactoferrin was found to function as a potent anti-inflammatory for the persistent inflammation seen in susceptible mares when administered post-breeding. This protein should be further investigated as a potential therapeutic for the treatment of persistent breeding-induced endometritis.

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29

Barnes, Amber K. "Zebrafish as a Model for Prenatal Alcohol Exposure: An Investigation Into Behavioral and Developmental Effects". University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1354306697.

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30

Tibayrenc, Pierre. "Mesures d'états au sein d'une population de levures : application à l'étude de la réponse de S. cerevisiae à différents stress technologiques liés à la production de bioéthanol". Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20027/document.

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Dans une démarche d'optimisation et de maîtrise d'un bioprocédé, une préoccupation importante concerne la mesure et le suivi de l'état des cellules. Au cours de cette thèse, des mesures in situ et/ou permettant de mettre en évidence une variabilité phénotypique au sein d'une population de levures ont été recherchées. La spectroscopie d'impédance, basée sur la capacité des cellules viables à se polariser sous l'effet d'un champ électrique, a été retenue pour estimer l'état des cellules en-ligne. Pour effectuer des mesures de morphologie et de viabilité à l'échelle de la cellule, un système complet de microscopie et d'analyse d'image automatisées a été développé, en parallèle de l'utilisation d'un compteur de cellules de type Coulter. Enfin, des suivis individuels de croissance sur milieu gélosé ont été réalisés afin de caractériser la population en termes de temps de latence et de vitesse de croissance. Le procédé modèle de cette étude est la production de bioéthanol, qui expose les levures utilisées (S. cerevisiae) à d'importantes contraintes physicochimiques (température, acétate, furfural,...) qui affectent leur état physiologique et limitent l'efficacité de l'étape de fermentation. La population, homogène sur le plan cinétique dans des conditions de culture non stressantes, devient hétérogène lorsqu'une perturbation est appliquée. La mesure de cette hétérogénéité peut être utilisée comme marqueur de la sévérité du stress subi. Au cours des phases de déclin, la mort s'accompagne d'une diminution de la taille des cellules et d'une modification de leur aspect en microscopie. Ces changements permettent d'estimer la proportion de cellules viables à partir des distributions de taille obtenues avec le compteur d'une part, et l'analyse des images de microscopie d'autre part. La spectroscopie d'impédance donne une estimation fiable de la fraction volumique de cellules viables et permet de mesurer la capacitance membranaire Cm, ainsi que la conductivité intracellulaire sin, des paramètres liés à l'état de la membrane et du cytoplasme. Cm, constante tant que les cellules sont viables, s'annule à leur mort, tandis que sin varie selon la phase de culture et en réponse aux stress
For bioprocess control and optimization, biomass monitoring and physiological state evaluation is an important issue. During this work, in situ and at-line measurements have been used to evaluate cell state and detect a phenotypic variability within a yeast population. Dielectric spectroscopy, based on the polarization of viable cell membranes exposed to an electrical field, has been selected to infer cell state on-line. In parallel with the use of a Coulter-type cell counter, a dedicated system of automated microscopy and image analysis has been developed to measure cell morphology and viability. Single-cell growth on agar medium was monitored to characterize individual cells with regard to lag-time and initial growth rate. Bioethanol production with S. cerevisiae has been chosen as a model process since the yeast cells are exposed to strong physicochemical stresses (temperature, acetate, furfural,?) which affect their physiological state and impair fermentation efficiency. The cell population, kinetically homogeneous during stress-free fermentations, became heterogeneous when a perturbation was applied. The mean and the variance of lag-time distributions were related to the stress severity. During the decline phase, cell death went along with a decrease in cell size and changes of their microscopy aspect. These changes were significant enough to infer the proportion of viable cells directly from the size distributions obtained with the cell counter or from microscopy image analysis. Dielectric spectroscopy gave reliable estimates of the viable cell volume fraction and enabled the measurements of membrane capacitance Cm and intracellular conductivity sin, parameters related to membrane and cytoplasm states. The Cm value remained constant as long as the cells were viable and dropped to zero at cell death, while sin varied significantly depending on the growth phase and in response to stress

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31

Wang, Ruoya. "Novel theoretical and experimental frameworks for multiscale quantification of arterial mechanics". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47718.

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The mechanical behavior of the arterial wall is determined by the composition and structure of its internal constituents as well as the applied traction-forces, such as pressure and axial stretch. The purpose of this work is to develop new theoretical frameworks and experimental methodologies to further the understanding of arterial mechanics and role of the various intrinsic and extrinsic mechanically motivating factors. Specifically, residual deformation, matrix organization, and perivascular support are investigated in the context of their effects on the overall and local mechanical behavior of the artery. We propose new kinematic frameworks to determine the displacement field due to residual deformations previously unknown, which include longitudinal and shearing residual deformations. This allows for improved predictions of the local, intramural stresses of the artery. We found distinct microstructural differences between the femoral and carotid arteries from non-human primates. These arteries are functionally and mechanically different, but are geometrically and compositionally similar, thereby suggesting differences in their microstructural alignments, particularly of their collagen fibers. Finally, we quantified the mechanical constraint of perivascular support on the coronary artery by mechanically testing the artery in-situ before and after surgical exposure.

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32

Cabana, Tanguy. "Large deviations for the dynamics of heterogeneous neural networks". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066551/document.

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Cette thèse porte sur l'obtention rigoureuse de limites de champ moyen pour la dynamique continue de grands réseaux de neurones hétérogènes. Nous considérons des neurones à taux de décharge, et sujets à un bruit Brownien additif. Le réseau est entièrement connecté, avec des poids de connections dont la variance décroît comme l'inverse du nombre de neurones conservant un effet non trivial dans la limite thermodynamique. Un second type d'hétérogénéité, interprété comme une position spatiale, est considéré au niveau de chaque cellule. Pour la pertinence biologique, nos modèles incluent ou bien des délais, ainsi que des moyennes et variances de connections, dépendants de la distance entre les cellules, ou bien des synapses dépendantes de l'état des deux neurones post- et présynaptique. Ce dernier cas s'applique au modèle de Kuramoto pour les oscillateurs couplés. Quand les poids synaptiques sont Gaussiens et indépendants, nous prouvons un principe de grandes déviations pour la mesure empirique de l'état des neurones. La bonne fonction de taux associée atteint son minimum en une unique mesure de probabilité, impliquant convergence et propagation du chaos sous la loi "averaged". Dans certains cas, des résultats "quenched" sont obtenus. La limite est solution d'une équation implicite, non Markovienne, dans laquelle le terme d'interactions est remplacé par un processus Gaussien qui dépend de la loi de la solution du réseau entier. Une universalité de cette limite est prouvée, dans le cas de poids synaptiques non-Gaussiens avec queues sous-Gaussiennes. Enfin, quelques résultats numérique sur les réseau aléatoires sont présentés, et des perspectives discutées
This thesis addresses the rigorous derivation of mean-field results for the continuous time dynamics of heterogeneous large neural networks. In our models, we consider firing-rate neurons subject to additive noise. The network is fully connected, with highly random connectivity weights. Their variance scales as the inverse of the network size, and thus conserves a non-trivial role in the thermodynamic limit. Moreover, another heterogeneity is considered at the level of each neuron. It is interpreted as a spatial location. For biological relevance, a model considered includes delays, mean and variance of connections depending on the distance between cells. A second model considers interactions depending on the states of both neurons at play. This last case notably applies to Kuramoto's model of coupled oscillators. When the weights are independent Gaussian random variables, we show that the empirical measure of the neurons' states satisfies a large deviations principle, with a good rate function achieving its minimum at a unique probability measure, implying averaged convergence of the empirical measure and propagation of chaos. In certain cases, we also obtained quenched results. The limit is characterized through a complex non Markovian implicit equation in which the network interaction term is replaced by a non-local Gaussian process whose statistics depend on the solution over the whole neural field. We further demonstrate the universality of this limit, in the sense that neuronal networks with non-Gaussian interconnections but sub-Gaussian tails converge towards it. Moreover, we present a few numerical applications, and discuss possible perspectives

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33

Olughu, Williams C. "The systematic consideration of the large-scale fed-batch fermentation inhomogeneities using a genetically modified C. glutamicum strain as a model organism". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/34284.

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The loss of efficiency and performance of bioprocesses on scale-up is well known, but not fully understood. This work addresses this problem, by studying the effect of some fermentation gradients (pH, glucose and oxygen) at a larger scale in a bench-scale two compartment reactor (PFR + STR) using the cadaverine-producing recombinant bacterium, Corynebacterium glutamicum DM1945 Δact3 Ptuf-ldcC_OPT. The initial scale down strategy increased the magnitude of these gradients by only increasing the mean cell residence time in the plug flow reactor (τ_PFR). The cell growth and product related rate constants were compared as the τ_PFR was increased; differences were significant in some cases, but only up to 2 min residence time. For example, losses in cadaverine productivity when compared to the control fed-batch fermentation on average for the τ_PFR of 1 min, 2 min and 5 min were 25 %, 42 % and 46 % respectively. This indicated that the increasing the τ_PFR alone does not necessarily increase the magnitude of fermentation gradients. The new scale-down strategy developed here, increased the magnitude of fermentation gradients by not only increasing the τ_PFR, but also considering the mean frequency at which the bacterial cells entered the PFR section (f_m). The f_m was kept constant by reducing the broth volume in the STR. Hence, the bacterial cells also spent shorter times in the well mixed STR, as the τ_PFR was increased (hypothesised as giving the bacterial cells less time to recover the non-ideal PFR section of the SDR). On adoption of this strategy cadaverine productivity decreases for the τ_PFR of 1 min, 2 min and 5 min were 25 %, 32 % and 53 % respectively. Thus, highlighting that loss in performance is most likely to occur as the magnitude of heterogeneity within the fermentation environment increases. However, Corynebacterium glutamicum DM1945 Δact3 Ptuf-ldcC_OPT did show some resilience in its biomass productivity. It was only marginally affected in the harshest of conditions simulated here.

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34

Dos, Ramos Catarino Ana Isabel. "Temperate and cold water sea urchin species in an acidifying world: coping with change?" Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209914.

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Abstract (sommario):

Anthropogenic carbon dioxide (CO2) emissions are increasing the atmospheric CO2 concentration and the oceans are absorbing around 1/3 them. The CO2 hydrolysis increases the H+ concentration, decreasing the pH, while the proportions of the HCO3- and CO32- ions are also affected. This process already led to a decrease of 0.1 pH units in surface seawater. According to "business-as-usual" models, provided by the Intergovernmental Panel on Climate Change (IPCC), the pH is expected to decrease 0.3-0.5 units by 2100 and 0.7-0.8 by 2300. As a result the surface ocean carbonates chemistry will also change: with increasing pCO2, dissolved inorganic carbon will increase and the equilibrium of the carbonate system will shift to higher CO2 and HCO3– levels, while CO32– concentration will decrease. Surface seawaters will progressively become less saturated towards calcite and aragonite saturation state and some particular polar and cold water regions could even become completely undersaturated within the next 50 years.

Responses of marine organisms to environmental hypercapnia, i.e. to an excess of CO2 in the aquatic environment, can be extremely variable and the degree of sensitivity varies between species and life stages. Sea urchins are key stone species in many marine ecosystems. They are considered to be particularly vulnerable to ocean acidification effects not only due to the nature of their skeleton (magnesium calcite) whose solubility is similar or higher than that of aragonite, but also because they lack an efficient ion regulatory machinery, being therefore considered poor acid-base regulators. Populations from polar regions are expected to be at an even higher risk since the carbonate chemical changes in surface ocean waters are happening there at a faster rate.

The goal of this work was to study the effects of low seawater pH exposure of different life stages of sea urchins, in order to better understand how species from different environments and/or geographic origins would respond and if there would be scope for possible adaptation and/or acclimatization.

In a first stage we investigated the effects of ocean acidification on the early stages of an intertidal species from temperate regions, the Atlantic Paracentrotus lividus sea urchin, and of a sub-Antarctic species, Arbacia dufresnei. The fertilization, larval development and larval growth were studied on specimens submitted through different pH experimental treatments. The fertilization rate of P. lividus gametes whose progenitors came from a tide pool with high pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress. Larval size in both species decreased significantly in low pH treatments. However, smaller A. dufresnei echinoplutei were isometric to those of control treatments, showing that size reduction was most likely due to a slower growth rate. In the pH 7.4 (predicted for 2300) treatment, P. lividus presented significantly more abnormal forms than control ones, but A. dufresnei did not. The latter does not seem to be more vulnerable than temperate species, most likely due to acclimatization/adaptation to lower pH seasonal fluctuations experienced by individuals of this population during spring time.

In a second stage, adult physiological responses of P. lividus and A. dufresnei to low pH seawaters were studied. Intertidal field P. lividus specimens can experience pH fluctuations of 0.4 units during low tidal cycles, but their coelomic fluid pH will not change. During experimental exposure to low pH, the coelomic fluid (extracellular) pH of both species decreased after weeks of exposure to low seawater pH. However, it owned a certain buffer capacity (higher than that of seawater) which did not seem to be related to passive skeleton dissolution. In laboratory studies, the feeding rate of P. lividus, the RNA/DNA ratio (proxy for protein synthesis and thus metabolism) of both the gonads and the body wall of the studied species and the carbonic anhydrase activity in the body wall (an enzyme involved in calcification and respiratory processes) of A. dufresnei did not differ according to seawater pH. The same was true for spine regeneration (a proxy for calcification) of both species. This shows that both P. lividus and A. dufresnei are able to cope when exposed to mild hypercapnia (lowest investigated pH 7.4) for a mid-term period of time (weeks). In a different set of experiments, pH effects were tested on P. lividus individuals together with two temperatures (10ºC and 16ºC). The pH decrease of the coelomic fluid did not vary between temperatures, neither did its buffer response. The oxygen uptake rates of P. lividus (as a proxy for global metabolic state of the whole organism) increased in lower pH treatments (7.7 and 7.4) in organisms exposed to lower temperatures (10ºC), showing that this was upregulated and that organisms experienced a higher energetic demand to maintain normal physiological functions. For instance, gonad production (given by the RNA/DNA ratio) was not affected neither by temperature, nor pH.

Finally, possible morphological and chemical adaptations of cidaroid (“naked”) spines, which are not covered by epidermis, to low magnesium calcite saturation states were investigated. Deep sea field specimens from the Weddell Sea (Antarctica), Ctenocidaris speciosa were studied. Cidaroid spines have an exterior skeleton layer with a polycrystalline constitution that apparently protects the interior part of the monocrystaline skeleton, the stereom (tridimensional magnesium calcite lattice). The cortex of C. speciosa was by its turn divided into two layers. From these, it presented a thicker inner cortex layer and a lower Mg content in specimens collected below the aragonite saturation horizon. The naked cortex seems able to resist to low calcium carbonate saturation state. We suggest that this could be linked to the important organic matrix that surrounds the crystallites of the cortex.

Some echinoid species present adaptive features that enable them to deal with low pH stresses. This seems to be related to the environmental conditions to which populations are submitted to. Therefore, organisms already submitted to pH daily or seasonal fluctuations or living in environments undersaturated in calcium carbonate seem to be able to cope with environmental conditions expected in an acidified ocean. Under the realistic scenario of a decrease of ca. 0.4 units of pH by 2100, sea urchins, and echinoderms in general, appear to be robust for most studied processes. Even thought, this general response can depend on different parameters such as exposure time, pH level tested, the process and the life stage considered, our results show that there is scope for echinoids to cope with ocean acidification.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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35

Ngounga, Tatsiana Olyane. "Outils moléculaires de détection des virus géants de la famille des Mimiviridae et des Marseilleviridae : application à des échantillons environnementaux et humains". Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5075.

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Les virus géants d'amibes( Acanthamoeba) sont des virus à ADN double brin . Ces virus géants ont été isolés depuis 2008 essentiellement à partir de prélèvements d'eaux et sols) collectés dans diverses régions géographiques à travers le monde, ou à partir de prélèvements humains (selle, liquide broncho-alvéolaire et sang). Ils sont repartis en 4 familles virales dont les plus représentées sont les familles Mimiviridae et Marseilleviridae avec pour membres fondateurs respectifs Mimivirus et Marseillevirus et comptent à ce jour respectivement 44 et 20 isolats. Les virus géants d'amibes sont ubiquitaires dans notre biosphère, et les êtres humains y sont potentiellement exposés. Au cours de cette Thèse, nous avons premièrement écrit une revue de la littérature décrivant les outils de mise en évidence des virus géants d'amibes chez l'homme incluant la sérologie, la culture, la PCR ou l'hybridation de sondes fluorescentes in situ. Deuxièmement, nous avons conçu et évalué 5 systèmes de PCR en temps réel détectant les membres des groupes de mimivirus d'amibes, leurs virophages et les marseillevirus. Nous avons participé à un 3ème travail décrivant les différentes procédures d'isolement sur amibes utilisées jusqu'à présent dans notre laboratoire . Enfin, dans un 4ème travail préliminaire, nous avons recherché par PCR la présence des mimivirus et marseillevirus dans 701 plasmas de patients infectés par HIV-1.Au total, nos travaux ont décrit les mises au point, performances et limites des tests de PCR pour l'étude des virus géants, et ont contribué aux outils et fourni des éléments pour l'étude de l'implication des virus géants d'amibes en pathologie humaine
The giant viruses of amoebas( Acanthamoeba) are double stranded DNA viruses. These giant viruses have been isolated essentially from water and soil samples collected in various geographic regions around the world or from human samples (stool, blood and bronchoalveolar fluid). These giant viruses are divided into four viral families among which those comprising the largest number of representatives are the Mimiviridae and Marseilleviridae families, whose respective founders are Mimivirus and Marseillevirus and comprise 44 and 20 representative members, respectively. Giant viruses of amoeba are ubiquitous in our biosphere, which means that humans can be exposed to them. In this Thesis, we initially wrote a review of the literature describing the tools to detect the present of these giant viruses in humans, including serology, culture isolation, PCR and fluorescence in situ hybridization (FISH). Secondly, we designed and evaluated the performance of five real-time PCR systems targeting the members of the 3 groups of mimiviruses of amoeba, their virophages and the marseilleviruses. We were involved in a third work that described the different isolation procedures on amoebae used so far in our laboratory for giant viruses. Finally, in a fourth preliminary work, we looked by PCR for the presence of mimiviruses and marseilleviruses DNA in 701 plasma from patients infected with HIV-1. In summary, our work described the developed PCR assays for the study of giant viruses, and their performance and limitations, and it contributed to the tools and evidence for the study of the involvement of the giant amoeba virus in human pathology

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36

Morais, Sofia Jacinto. "Digestive physiology and food intake in marine fish larvae with respect to dietary neutral lipids". Doctoral thesis, 2005. http://hdl.handle.net/10400.1/768.

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Tese dout., Aquacultura, Universidade do Algarve, 2005
A growth depressing effect of high dietary neutral lipid levels in marine fish larvae has been reported. This may be the result of a decrease in the efficiency or activity of digestive enzymes, a reduction in absorption efficiency and/or a decrease in food intake. In this thesis, work was carried out on commercially valuable species (Atlantic herring, Senegalese sole, European seabass and gilthead seabream), to investigate the effects of neutral lipid level and source (fatty acid composition) on some of these key factors influencing larval growth. The results seem to collectively indicate that lipid transport from the enterocytes into the body may be more problematic in larval stages dealing with high neutral lipid diets than lipid digestion, although both factors are likely to intervene. Food intake did not appear to be strictly regulated by total lipid content of the diet and lipid source may have an important role in controlling ingestion. Therefore, the neutral lipid level in diets for marine fish larvae has a significant impact in several factors influencing growth but clearly it cannot be dissociated of its fatty acid composition, which appears to play a central role on the nutritional and physiological effects of dietary lipid, at the ingestion, digestion and absorption levels.
Fundação para a Ciência e a Tecnologia (FCT)

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37

Baßfeld, Eiko. "Imaging-Analyse dopaminerger Wirkungen am olfaktorischen Nerven von Xenopus-laevis-Larven". Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0001-BC25-7.

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38

Viegas, Ana Rita Gomes. "The effect of L-glutamine supplementation on the digestive physiology of Senegalese sole larvae, Solea senegalensis (Kaup, 1858)". Master's thesis, 2020. http://hdl.handle.net/10400.1/15260.

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Senegalese sole (Solea senegalensis) is an altricial species, which undergo dramatic transformations before metamorphosing into juvenile. Therefore, larvae must capture and process exogenous food even though the digestive tract may not be fully developed. The inadequate digestion/absorption of exogenous nutrients resulting from late maturation of the enterocytes at the intestinal epithelium has hampered a successful juvenile production of this promising flatfish species. Glutamine is a conditionally essential FAA which is involved in immune function and intestinal health, and has been widely used in aquaculture. A 22-day feeding trial was conducted to evaluate the effect of dietary L-glutamine supplementation on the growth performance, survival, metamorphosis, and digestive physiology during the early life stage of Senegalese sole. Two experimental diets were established with different levels of L-glutamine enrichments – 0.0 g l-1 (CTL) and 0.5 g l-1 (GLN). Experimental treatments were randomly assigned to triplicate groups stocked at a density of 0.26 individuals cm-2, reduced to 0.14 individuals cm-2 at 19 DAH, in each tank. The results showed that growth performance and enterocyte height of fish fed L-glutaminesupplemented diet were significantly increased compared to the control group (p<0.05). Survival and metamorphosis were not significantly different between dietary groups (p>0.05). Significant improvements were observed on specific activity of pepsin-like and amylase from CTL group, whereas BB aminopeptidase was highlighted in GLN group (p<0.05). Total activity of pepsin-like, amylase and acid phosphatase from CTL group was greater (p<0.05) than GLN group, whereas BB aminopeptidase total activity and IMI assayed through this enzyme showed better results in GLN group. Specific and total activity of trypsin, aminopeptidase, and intestinal and BB alkaline phosphatase did not differ between groups. Also, acid phosphatase specific activity was not affected by dietary L-glutamine. In conclusion, dietary L-glutamine supplementation could improve the growth performance and enterocyte height at the intestinal epithelium of sole post-larvae. Further studies are needed to clarify the effect of L-glutamine supplementation on enzymatic activity.
Com o contínuo aumento da população, um dos maiores desafios da atualidade baseia-se na procura de novas formas de satisfazer as necessidades alimentares, através de uma dieta saudável, rica em proteínas. Com a estabilização da produção pesqueira, resultante da sobre-exploração de grande parte dos recursos haliêuticos, e perante o progressivo aumento do consumo global de peixe, a aquacultura surge como uma alternativa viável para a produção de proteína de elevada qualidade nutricional, a um preço relativamente baixo. A produção de linguado do Senegal (Solea senegalensis) tem sido fomentada para a diversificação da aquacultura na Europa. Além de possuir um elevado valor nutritivo, esta espécie de elevado valor comercial apresenta um vasto leque de caraterísticas produtivas vantajosas, que tornam a sua produção economicamente competitiva. Devido aos avanços tecnológicos e científicos alcançados nas últimas décadas, entre os quais sobre a biologia reprodutiva, comportamento, requisitos nutricionais e fisiologia digestiva, o linguado senegalês tem vindo a exibir sinais de expansão na sua produção a nível industrial. Consequentemente, a produção de linguado senegalês tem vindo a apresentar uma elevada demanda de forma a atender as necessidades do mercado, que não são completamente satisfeitas pelas capturas pesqueiras. Posto isto, há uma necessidade urgente de aumentar a quantidade de larvas e juvenis de linguado senegalês de elevada qualidade, que passa por solucionar as complicações ainda existentes na fase larvar. A fase de transição larva-juvenil representa ainda um período crítico na produção de linguado marcado pela elevada taxa de mortalidade, especialmente aquando a metamorfose ou a passagem do alimento vivo para alimento inerte (desmame). Durante o desenvolvimento larvar, as elevadas exigências nutricionais, impostas pelo rápido crescimento e maturação dos tecidos, podem, por vezes, ser limitadas pela reduzida eficiência digestiva. A reduzida capacidade digestiva, que o linguado senegalês apresenta durante o desenvolvimento larvar, pode ser atribuída à maturação tardia do intestino, que ocorre por volta dos 25 dias após eclosão (DAE); três semanas após o início da alimentação exógena. Desta forma, há o interesse em promover um desenvolvimento mais rápido do trato digestivo nas larvas de linguado, na medida em que o epitélio intestinal, ao estar diretamente relacionado com a absorção e digestão dos nutrientes, poderá proporcionar melhores taxas de sobrevivência e assegurar um melhor desempenho produtivo. Vários estudos têm demonstrado o potencial da glutamina na fisiologia digestiva de diversos organismos aquáticos. Além de impedir a atrofia da mucosa intestinal, este aminoácido é capaz de promover a maturação intestinal através do aumento das vilosidades intestinais, bem como das células epiteliais (enterócitos) nelas presentes. Devido à versatilidade da glutamina e à miríade de efeitos benéficos associados, a sua utilização tem sido foco de investigação na área da nutrição e visa aumentar a produção comercial de organismos aquáticos. Na última década, a utilização da glutamina como suplemento dietético tem vindo a ser testada nas fases iniciais do desenvolvimento de algumas espécies, como a Tilápia do Nilo (Oreochromis niloticus) e linguado (Cynoglossus semilaevis). No âmbito desta necessidade de promover uma rápida maturação do trato digestivo do linguado senegalês, o presente estudo, integrado no projeto DIVERSIAQUAII, teve como principal objetivo avaliar o efeito da suplementação dietética com L-glutamina ao nível da fisiologia digestiva de pós-larvas de S. senegalensis. Para tal, foram estabelecidos dois grupos experimentais: Grupo controlo (CTL), no qual as pós-larvas de linguado senegalês foram alimentadas com metanáuplios de Artemia sp. enriquecidos com Red Pepper (BERNAQUA), uma emulsão comercial (1,0 ± 0,23 mg L-glutamina/g de peso seco de Artemia sp.); e o Grupo L-glutamina (GLN), no qual as pós-larvas de linguado senegalês foram alimentadas com metanáuplios de Artemia sp. enriquecidos com L-glutamina (em pó) (2,2 ± 0,06 mg Lglutamina/ g de peso seco de Artemia sp.). Um total de 13 140 larvas (peso seco inicial de 0,37 ± 0,05 mg) de linguado senegalês foram aleatoriamente distribuídas por 6 tanques retangulares (n=3, por cada tratamento experimental). A alimentação foi fornecida ad libitum cinco vezes ao dia, desde os 12 até aos 33 DAE. Durante o período experimental foram realizadas cinco amostragens, de forma a avaliar os seguintes parâmetros: comprimento total, peso seco, estado metamórfico, altura dos enterócitos, atividade específica e total das enzimas digestivas e das localizadas na borda em escova dos enterócitos. Com base nos dados de alguns destes parâmetros, foram também determinadas a taxa de crescimento relativa e o índice de maturação intestinal. A taxa de sobrevivência foi obtida com base nos registos de mortalidade registados diariamente. Relativamente ao comprimento total e peso seco, as pós-larvas de linguado senegalês alimentadas com Artemia sp. enriquecida com L-glutamina apresentaram valores superiores aos do grupo CTL. Da mesma forma, a taxa de crescimento relativa do grupo GLN foi significativamente maior a partir dos 26 DAE, comparativamente ao grupo CTL. No entanto, tanto a sobrevivência como os estados metamórficos não diferiram entre tratamentos experimentais. A suplementação com L-glutamina na dieta das pós-larvas de linguado senegalês promoveu melhorias na altura dos enterócitos do epitélio intestinal. Em relação aos dados obtidos através da análise enzimática, a atividade específica da pepsina e da amilase do grupo CTL destacaram-se positivamente, em comparação com o grupo GLN; enquanto a atividade específica da aminopeptidase, avaliada ao nível da borda em escova dos enterócitos, foi potenciada pela suplementação de L-glutamina na dieta. A atividade total da pepsina, amilase e fosfatase ácida, exibidas pelo grupo CTL, foi superior à das pós-larvas de linguado senegalês alimentadas com uma dieta suplementada com Lglutamina. A atividade total da aminopeptidase analisada ao nível da borda em escova dos enterócitos, bem como o índice de maturação intestinal calculado a partir desta enzima, foram promovidos pelo uso de L-glutamina como suplemento dietético no protocolo alimentar das pós-larvas de linguado. Tanto a atividade específica como a atividade total da tripsina, aminopeptidase e fosfatase alcalina (intestinal e da borda em escova dos enterócitos) não diferiram entre tratamentos experimentais. Da mesma forma, não foram observados efeitos da suplementação de L-glutamina na dieta ao nível da atividade específica da fosfatase ácida. Os resultados obtidos mostram, pela primeira vez, que em pós-larvas de linguado senegalês, o uso de L-glutamina como suplemento dietético pode promover melhorias ao nível do desempenho de crescimento. Além disso, com base nos dados histológicos, os resultados obtidos nesta tese suportam a possibilidade de a suplementação com L-glutamina acelerar a maturação do intestino durante o desenvolvimento larvar de S. senegalensis. Porém, é ainda necessário desenvolver outros estudos de forma a clarificar o efeito da suplementação com Lglutamina na atividade enzimática das pós-larvas de linguado senegalês.

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39

Pérez-Domínguez, Rafael. "Effects of nursery-environment condition on habitat use, growth, survival and endocrine physiology during larval settlement in the red drum (Sciaenops ocellatus)". Thesis, 2004. http://www.lib.utexas.edu/etd/d/2004/perezdominguezr32844/perezdominguezr32844.pdf#page=3.

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40

Waheed, Ahmed. "The influence of social and environmental factors on the stress response and development in juvenile & larval lake sturgeon, Acipenser fulvescens". 2012. http://hdl.handle.net/1993/5087.

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This thesis has examined the influence of the environment on aspects of the acute stress response in juvenile and pro-larval Acipenser fulvescens.The acute stress response was examined in grouped and isolated juveniles. Catecholamines significantly increased in both treatments one minute post-stress and plasma glucose was significantly higher in isolated as compared to grouped fish one minute post-stress. In the second series of experiments fertilized eggs of A. fulvescens were raised at 9, 12 & 15°C. Chromaffin-like cells were studied using light and electron microscopy techniques. Development of renal tissue was also examined in these treatment groups. Two populations of chromaffin-like cells were identified, one in close association with the proximal tubule of the kidney, and the other in close association with the neural tube. Results suggest this latter population were immature pheochromoblast like-cells. Development of renal tissue followed a predictable pattern that was most rapid in the 15°C treatment.

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41

"TRPV4-TRPC1- BKca tri-complex mediates epoxyeicosatrienoic acid-induced membrane hyperpolarization". Thesis, 2011. http://library.cuhk.edu.hk/record=b6075501.

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Ma, Yan.
"Ca" in the title is subscript.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references (leaves 143-166).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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42

Applebaum, Scott Lee 1974. "Regulation of elements of the thyroid hormone and corticosteroid systems by stress, hormone treatment, and atrazine during ontogeny of red drum (Sciaenops ocellatus)". 2008. http://hdl.handle.net/2152/17730.

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Survival of teleost larvae requires growth and development which depend upon endocrine processes. In this dissertation I have examined the ontogeny of elements of the thyroid hormone (TH) and corticosteroid (CS) systems in red drum (Sciaenops ocellatus). Basal cortisol production was first detected 3 days post-hatch (DPH) and a cortisol stress response was present from 6 DPH forward. Changes in steroidogenic enzyme mRNA (CYP11B and CYP21) levels did not correlate with these events. The time necessary to reach peak cortisol levels as well as return to basal levels declined as larvae developed. A second set of studies examined ontogenetic patterns in levels of mRNAs encoding thyroid (soTR[alpha] and soTR[beta]) and corticosteroid (soGR) hormone receptors and assessed the regulation of these mRNAs by exogenous triiodothyronine (T3) and cortisol. soTR[alpha], soTR[beta] and soGR were expressed in all stages of red drum examined. soTR[alpha] levels increased during the time when surging TH levels have been reported. soTR[beta] levels did not differ significantly during development. soGR levels were strongly correlated with those of soTR[alpha]. T3 up-regulated soTR[alpha] and soTR[beta] levels in 7 DPH, but not older larvae. Cross-regulation of receptor mRNAs by exogenous treatment with T3 or cortisol was not observed. Finally, I assessed the influence of a common herbicide, atrazine, on receptor mRNA, TH levels and growth of red drum. In two experiments, red drum exposed to environmentally relevant levels of atrazine did not alter hormone receptor mRNA levels, or TH content. However, atrazine did depress growth in some instances. In conclusion, the expression patterns of hormone receptor mRNA in embryos suggests receptor proteins could be activated by maternal hormones prior to the onset of endogenous hormone production. A correlation between soTR[alpha] and soGR mRNA levels suggests coordinated function of TH and CS systems, although regulatory interactions between these systems were not evident under the conditions in this study. Patterns in soTR[alpha] and soTR[beta] mRNA levels support an important role for TH in the larval to juvenile transformation of red drum larvae. The results also support growing evidence indicating atrazine exposure effects larval growth and may impact their survival in the wild.
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43

Ziegler, Tracy Ann. "Larval Release Rhythms and Larval Behavior of Palinurid Lobsters a comparative study". Diss., 2007. http://hdl.handle.net/10161/456/1/D_Ziegler_Tracy_a_200712.pdf.

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44

Whale, John W. "Population genetic analysis of the black blow fly Phormia regina (Meigen) (Diptera: Calliphoridae)". Thesis, 2015. http://hdl.handle.net/1805/6722.

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Indiana University-Purdue University Indianapolis (IUPUI)
The black blow fly, Phormia regina (Diptera: Calliphoridae), is a widely abundant fly autochthonous to North America. Like many other Calliphorids, P. regina plays a key role in several disciplines particularly in estimating post-mortem intervals (PMI). The aim of this work was to better understand the population genetic structure of this important ecological species using microsatellites from populations collected in the U.S. during 2008 and 2013. Additionally, it sought to determine the effect of limited genetic diversity on a quantitative trait throughout immature development; larval length, a measurement used to estimate specimen age. Observed heterozygosity was lower than expected at five of the six loci and ranged from 0.529-0.880 compared to expected heterozygosity that ranged from 0.512-0.980, this is indicative of either inbreeding or the presence of null alleles. Kinship coefficients indicate that individuals within each sample are not strongly related to one another; values for the wild-caught populations ranged from 0.033-0.171 and a high proportion of the genetic variation (30%) can be found among samples within regions. The population structure of this species does not correlate well to geography; populations are different to one another resulting from a lack of gene flow irrespective of geographic distance, thus inferring temporal distance plays a greater role on the genetic variation of P. regina. Among colonized samples, flies lost much of their genetic diversity, ≥67% of alleles per locus were lost, and population samples became increasingly more related; kinship coefficient values increased from 0.036 for the wild-caught individuals to 0.261 among the F10 specimens. Colonized larvae also became shorter in length following repeated inbreeding events, with the longest recorded specimen in F1 18.75 mm in length while the longest larva measured in F11 was 1.5 mm shorter at 17.25 mm. This could have major implications in forensic entomology, as the largest specimen is often assumed to be the oldest on the corpse and is subsequently used to estimate a postmortem interval. The reduction in length ultimately resulted in a greater proportion of individuals of a similar length; the range of data became reduced. Consequently, the major reduction in genetic diversity indicates that the loss in the spread of length distributions of the larvae may have a genetic influence or control. Therefore, this data highlights the importance when undertaking either genetic or development studies, particularly of blow flies such as Phormia regina, that collections of specimens and populations take place not only from more than one geographic location, but more importantly from more than one temporal event.

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45

(10724124), Elizabeth B. Allmon. "Cardiotoxic effects of polycyclic aromatic hydrocarbons and abiotic stressors in early life stage estuarine teleosts". Thesis, 2021.

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Following the 2010 Deepwater Horizon oil spill, extensive research has been conducted on the toxicity of oil and polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment. The location and timing of the Deepwater Horizon surface slick coincided with the spawning seasons of many important pelagic and estuarine fish species. As such, there has been particular emphasis placed on the effects of PAHs on sensitive life history stages in fish, such as the embryonic and larval periods. Additionally, the spill occurred throughout the spring and summer months which, in estuaries, are marked by regular fluctuations in abiotic environmental factors such as dissolved oxygen, salinity, and temperature. Until recently, there has been little work done to elucidate the combined effects that PAHs from oil spills and adverse environmental conditions (hypoxia, increased salinity, and elevated temperatures).

Work presented in this dissertation uses next generation sequencing technology (RNA Seq) to determine differential gene expression in larval estuarine teleosts following exposure to adverse environmental conditions and PAHs. Downstream canonical pathway and toxicological function analysis were then applied to the identified differentially expressed genes (DEGs) to predict cardiotoxic responses at the organismal level. To verify the predicted responses, a phenotypic anchoring study was conducted and identified a cardiotoxic phenotype (pericardial edema) and reduced cardiac output in embryos exposed to oil. Finally, the mechano-genetic interplay governing the morphological development of the teleost heart was investigated and correlations between developmental gene expression and blood flow forces within the cardiovascular system were identified.

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Andere, Anne A. "De novo genome assembly of the blow fly Phormia regina (Diptera: Calliphoridae)". Thesis, 2014. http://hdl.handle.net/1805/5630.

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Indiana University-Purdue University Indianapolis (IUPUI)
Phormia regina (Meigen), commonly known as the black blow fly is a dipteran that belongs to the family Calliphoridae. Calliphorids play an important role in various research fields including ecology, medical studies, veterinary and forensic sciences. P. regina, a non-model organism, is one of the most common forensically relevant insects in North America and is typically used to assist in estimating postmortem intervals (PMI). To better understand the roles P. regina plays in the numerous research fields, we re-constructed its genome using next generation sequencing technologies. The focus was on generating a reference genome through de novo assembly of high-throughput short read sequences. Following assembly, genetic markers were identified in the form of microsatellites and single nucleotide polymorphisms (SNPs) to aid in future population genetic surveys of P. regina. A total 530 million 100 bp paired-end reads were obtained from five pooled male and female P. regina flies using the Illumina HiSeq2000 sequencing platform. A 524 Mbp draft genome was assembled using both sexes with 11,037 predicted genes. The draft reference genome assembled from this study provides an important resource for investigating the genetic diversity that exists between and among blow fly species; and empowers the understanding of their genetic basis in terms of adaptations, population structure and evolution. The genomic tools will facilitate the analysis of genome-wide studies using modern genomic techniques to boost a refined understanding of the evolutionary processes underlying genomic evolution between blow flies and other insect species.

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Tesi sul tema "Larves – Physiologie"

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