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Helmstetter Cécile - One of the best experts on this subject based on the ideXlab platform.
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Réponses morpho-fonctionnelles du système digestif du Python de Birmanie (Python Molurus bivittatus) au jeûne et à la réalimentation
Université Louis Pasteur, 2008Co-Authors: Helmstetter CécileAbstract:Le jeûne et la régulation des fonctions digestives sont des thèmes qui ont été longuement étudiés chez les Vertébrés supérieurs. La description des étonnantes capacités de jeûne du Python de Birmanie, Python Molurus, a ainsi soulevé de nombreuses interrogations et laissé supposer l’existence de réponses physiologiques ajustées à la privation d’aliments différentes de celles des Mammifères. Cette thèse s’inscrit dans ce contexte d’exploration fonctionnelle du système digestif de Python Molurus bivittatus. Elle a en effet pour objet de décrire les adaptations morpho-fonctionnelles requises par le jeûne et la réalimentation, d’en déterminer les mécanismes sous-jacents et de comprendre quelles en sont les portées écologiques…[etc.
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Réponses morpho-fonctionnelles du système digestif du Python de Birmanie (Python Molurus bivittatus) au jeûne et à la réalimentation
2008Co-Authors: Helmstetter CécileAbstract:Le jeûne et la régulation des fonctions digestives sont des thèmes qui ont été longuement étudiés chez les Vertébrés supérieurs. La description des étonnantes capacités de jeûne du Python de Birmanie, Python Molurus, a ainsi soulevé de nombreuses interrogPas de résum
J.a.j. Breeuwer - One of the best experts on this subject based on the ideXlab platform.
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Molecular genetic evidence for parthenogenesis in the Burmese Python, Python Molurus bivittatus
Heredity, 2003Co-Authors: T V M Groot, E Bruins, J.a.j. BreeuwerAbstract:Parthenogenesis among reptiles is rare. Only a few species have the ability to reproduce asexually. Most of these are obligate parthenogenetic species that consist (almost) entirely of females, which can reproduce solely through parthenogenesis. Rarer are sexual species that only sporadically reproduce through parthenogenesis. A female Python Molurus bivittatus (Reptilia, Boidae) from the Artis Zoo, Amsterdam, produced eggs in five consecutive years that contained embryos while she was isolated from males. These eggs might be fertilized with stored sperm, or might be the product of parthenogenesis. Parthenogenesis has not been shown for the Boidae family before. We performed parentship analyses on the snake and seven of her embryos using microsatellites and AFLP. Four microsatellite loci developed for this species combined with three loci developed previously for different snake species revealed too little variation to discriminate between sperm retention and parthenogenesis. With AFLP we were able to confirm that the Artis Zoo female reproduced parthenogenetically. Because the offspring are genetically identical to their mother, whereas in previous studies on sporadic parthenogenesis in snakes a loss of genetic information was reported, we conclude that the meiotic pathways that produce the diploid egg cells are different.
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Molecular genetic evidence for parthenogenesis in the Burmese Python, Python Molurus bivittatus. Heredity
2003Co-Authors: T V M Groot, E Bruins, J.a.j. BreeuwerAbstract:Parthenogenesis among reptiles is rare. Only a few species have the ability to reproduce asexually. Most of these are obligate parthenogenetic species that consist (almost) entirely of females, which can reproduce solely through parthenogenesis. Rarer are sexual species that only spor-adically reproduce through parthenogenesis. A female Python Molurus bivittatus (Reptilia, Boidae) from the Artis Zoo, Amsterdam, produced eggs in five consecutive years that contained embryos while she was isolated from males. These eggs might be fertilized with stored sperm, or might be the product of parthenogenesis. Parthenogenesis has not been shown for the Boidae family before. We performed parentship analyses on the snake and seven of her embryos using microsatellites and AFLP. Four microsatellite loci developed for this species combined with three loci devel-oped previously for different snake species revealed too little variation to discriminate between sperm retention and parthenogenesis. With AFLP we were able to confirm that the Artis Zoo female reproduced parthenogenetically. Be-cause the offspring are genetically identical to their mother, whereas in previous studies on sporadic parthenogenesis in snakes a loss of genetic information was reported, we conclude that the meiotic pathways that produce the diploid egg cells are different
Frank J Mazzotti - One of the best experts on this subject based on the ideXlab platform.
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Invasive Species Distribution Notes Reproduction of the Burmese Python (Python Molurus bivittatus) in southern Florida
2015Co-Authors: Kenneth L. Krysko, Ray W Snow, James C. Nifong, Kevin M. Enge, Frank J MazzottiAbstract:Python Molurus bivittatus is the largest exotic herpetofaunal species documented as being established in the United States. From 1995 through July 2005, 160 P. m. bivittatus were removed from Everglades National Park (ENP) and surrounding areas in southern Florida (Snow et al., 2007b). Although the first juvenile sized (82.5 cm Total Length, TL) P. m. bivittatus was found in December 1995, the first evidence of reproduction was not documented until the collection of four neonate
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a field test of attractant traps for invasive burmese Pythons Python Molurus bivittatus in southern florida
Wildlife Research, 2011Co-Authors: Robert N. Reed, Kristen M Hart, Ray W Snow, Michael S Cherkiss, Frank J Mazzotti, Gordon H Rodda, Rondald Rozar, Scott M GoetzAbstract:Context. Invasive Burmese Pythons (Python Molurus bivittatus) are established over thousands of square kilometres of southern Florida, USA, and consume a wide range of native vertebrates. Few tools are available to control the Python population, and none of the available tools have been validated in the field to assess capture success as a proportion of Pythons available to be captured. Aims. Our primary aim was to conduct a trap trial for capturing invasive Pythons in an area east of Everglades National Park,wheremanyPythonshadbeencapturedinpreviousyears,toassesstheefficacyoftrapsforpopulationcontrol.Wealso aimed to compare results of visual surveys with trap capture rates, to determine capture rates of non-target species, and to assess capture rates as a proportion of resident Pythons in the study area. Methods.Weconductedamedium-scale(6053trapnights)experimentusingtwotypesofattractanttrapsbaitedwithlive ratsintheFrogPondareaeastofEvergladesNationalPark.Wealsoconductedstandardisedandopportunisticvisualsurveys inthetrappingarea.Followingthetrap trial,theareawasdischarrowedtoexposePythonsandallowcalculationof anindex of the number of resident Pythons. Key results. We captured three Pythons and 69 individuals of various rodent, amphibian, and reptile species in traps. Eleven Pythons were discovered during disc harrowing operations, as were large numbers of rodents. Conclusions. The trap trial captured a relatively small proportion of the Pythons that appeared to be present in the study area, although previous research suggests that trap capture rates improve with additional testing of alternative trap designs. Potential negative impacts to non-target species were minimal. Low Python capture rates may have been associated with extremely high local prey abundances during the trap experiment. Implications. Results of this trial illustrate many of the challenges in implementing and interpreting results from tests of control tools for large cryptic predators such as Burmese Pythons.
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birds consumed by the invasive burmese Python Python Molurus bivittatus in everglades national park florida usa
The Wilson Journal of Ornithology, 2011Co-Authors: Carla J Dove, Ray W Snow, Michael R Rochford, Frank J MazzottiAbstract:We identified 25 species of birds representing nine avian Orders from remains in digestive tracts of 85 Burmese Pythons (Python Molurus bivittatus) collected in Everglades National Park, Florida, USA, from 2003 to 2008. Four species of birds identified in this study are of special concern in Florida and a fifth, the Wood Stork (Mycteria americana), is listed as federally endangered. This represents the first detailed analysis of the avian component of the diet of the introduced Burmese Python, now established in Everglades National Park, Florida and highlights the potential for considerable negative impact of this invasive species on native bird populations. Received 9 June 2010. Accepted 27 September 2010.
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thermoregulation by a brooding burmese Python Python Molurus bivittatus in florida
Southeastern Naturalist, 2010Co-Authors: Ray W Snow, Alexander J Wolf, Brian W Greeves, Michael S Cherkiss, Robert L Hill, Frank J MazzottiAbstract:Abstract We report an observation of shivering thermogenesis and insulation by a brooding Python Molurus bivittatus (Burmese Python) just outside the northern boundary of Everglades National Park, FL. Temperature data loggers were placed in and around the brooding female's nest, and video was taken of the female performing shivering thermogenesis. Nest temperatures were maintained both warmer and cooler than ambient temperatures. This observation of thermoregulation through shivering thermogenesis and clutch insulation is the first documented instance of a Burmese Python exhibiting this behavior in the wild.
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assessing the impacts of Pythons in the greater everglades examination of diet and thermal biology of Python Molurus bivittatus
2010Co-Authors: Kristen M Hart, Frank J Mazzotti, Mchael E Dorcas, Skip SnowAbstract:The Burmese Python (Python Molurus bivittatus), a native to Southeast Asia, can reach a length greater than twenty feet (Wall 1921, Pope 1961). This Python is a long lived (15 - 25 years) behavioral, habitat, and dietary generalist, capable of producing large clutches of eggs (8 - 107) (Lederer 1956, Branch and Erasmus 1984). Observations of Burmese Pythons exist in the United States primarily from locations within Everglades National Park (ENP), including; along the Main Park Road in the saline and freshwater glades, and mangroves, between Pay-hay-okee and Flamingo, the greater Long Pine Key area (including Hole-in-the-Donut), and the greater Shark Valley area along the Tamiami Trail (including L-67 Ext.). The non-native species has also been observed repeatedly on the eastern boundary of ENP, along canal levees, in the remote mangrove backcountry, and in Big Cypress National Preserve. From 2002 (when the numbers first began to climb) to 2005, 201 Pythons were captured and removed or found dead. In 2006-2007 alone, that number more than doubled to 418. Measured total length for snakes recovered ranged from 0.5 m to 4.5 m including five hatchling-sized animals recovered in the summer of 2004, and two hatchlings captured in 2005. In 2008, 343 Pythons were removed, and so far in 2009, 347 individuals have been removed. The non-native semi-aquatic Pythons's diet in southern Florida includes raccoon, rabbit, muskrat, squirrel, opossum, cotton rat, black rat, bobcat, house wren, pied-billed grebe, white ibis, limpkin, alligator and endangered Key Largo wood rat. As Python Molurus is known to eat birds, and also known to frequent wading bird colonies in their native range, the proximity of Python sightings to the Paurotis Pond and Tamiami West wood stork rookeries is troubling. The potential for Pythons to eat Mangrove Fox Squirrels and Cape Sable Seaside Sparrows and to compete with Indigos Snakes is also of concern. Burmese Pythons present a potential threat to successful ecological restoration of the greater Everglades (NRC 2005). Pythons are now established and breeding in South Florida. Python Molurus bivittatus has the potential to occupy the entire footprint of the Comprehensive Everglades Restoration Project (CERP), adversely impacting valued resources across the landscape. Proposed management and control actions must include research strategies and further evaluation of potential impacts of Pythons. The results of this project will be applied to develop a comprehensive, science-based control and containment program. The proposed project will also increase our understanding of the impacts of Burmese Pythons on native fauna in DOI and surrounding lands. Dealing with established exotic species requires that we understand their status and impacts, and how to remove them. A current priority item for determining status is finding out the extent of invasion by established species. Once we know where the threat is occurring, we need a better understanding of how the threat may manifest itself ecologically-that is, what are the impacts of invasion? We can hypothesize that Burmese Pythons compete with native snakes or affect populations of prey species; however, knowing with certainty that Pythons eat wood rats, for example, better focuses eradication efforts and spurs action. A study of diet of Burmese Pythons directly addresses this issue. Further, knowing how much Pythons eat through a bioenergetic model allows us to forecast with more certainty predation impacts on native fauna.
Eliton Da Silva Vasconcelos - One of the best experts on this subject based on the ideXlab platform.
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effects of feeding and digestion on myocardial contractility and expression of calcium handling proteins in burmese Pythons Python Molurus
Comparative Biochemistry and Physiology B, 2020Co-Authors: Eliton Da Silva Vasconcelos, Ana Lucia Kalinin, Rafael Correa Cipriano, Samuel Santos Beserra, Andre Guelli Lopes, Cleo Alcântara Da Costa Leite, Diana Amaral MonteiroAbstract:Abstract Pythons are important models of studies on postprandial metabolism because their physiological responses are exacerbated when digesting large prey. Prior studies of these animals have shown hypertrophy of the cardiac tissue 2 to 3 days after feeding, coinciding with the peak of the specific dynamic action (SDA), but the consequences of this remodeling in myocardial contractility have not been studied, which is the purpose of this work. Specimens of Python Molurus were divided into two groups: a Digesting group (2 days after feeding, at the peak of SDA), and a Fasting group (28 days after feeding). When compared to the Fasting group, the Digesting group showed higher relative ventricular mass and calcium-handling protein expression such as sarcoplasmic reticulum Ca2+-ATPase (SERCA), phospholamban (PLB), and the Na+/Ca2+ exchanger (NCX). Digesting Pythons also exhibited significant increases in the cardiac contraction force (Fc), rates of force development and relaxation, and cardiac pumping capacity. Therefore, the higher SERCA, PLB and NCX expression levels increased cytosolic Ca2+ transient amplitude, improving myofilament force. These changes are crucial to maintain cardiac output and a relatively high and continuous blood flow required by metabolic expenditure that occurs in postprandial animals.
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Análise da expressão de proteínas envolvidas no manejo de cálcio cardíaco nos répteis píton (Python Molurus), cascavel sul-americana (Crotalus durissus terrificus) e jacaré-de-papo-amarelo (Caiman latirostris) em jejum e nos períodos digestivo e pós-absortivo
Universidade Federal de São Carlos, 2014Co-Authors: Eliton Da Silva VasconcelosAbstract:As proteínas Ca2+-ATPase do Retículo Sarcoplasmático (SERCA2), Fosfolambam (PLB) e o Trocador Na+/Ca2+ (NCX) são fundamentais para o manejo do cálcio e a contratilidade miocárdica nos vertebrados. A elevação da taxa metabólica gerada a partir dos processos mecânicos e fisiológicos da digestão é conhecida como "ação dinâmica específica" (SDA) e representa o custo energético do processamento, digestão e absorção dos alimentos. Em vários grupos de répteis, a alimentação gera um rápido aumento nas taxas de troca gasosa, cujo pico ocorre geralmente um dia ou dois após a alimentação, antes de sofrer um declínio mais lento e retornar aos valores pré-prandiais. A ingestão de grandes massas de alimento demanda uma elevação metabólica e leva a uma compensação na massa ventricular e um aumento na força de contração do miocárdio, evitando uma sobrecarga no sistema cardiovascular. Durante o jejum ocorre depleção da estrutura corpórea podendo também atingir o músculo cardíaco. Para descrever a importância e as mudanças nas proteínas SERCA2, PLB e NCX diante os efeitos da alimentação/digestão nos répteis cascavel sul-americana (Crotalus durissus terrificus), na píton (Python Molurus) e também do jejum prolongado no jacaré-de-papo-amarelo (Caiman latirostris), utilizada a técnica molecular Western blotting. Observou-se a existência de homologia entre as proteínas dos répteis com relação aos mamíferos. A SDA levou a uma maior expressão da proteína SERCA2 nas três espécies de répteis. A SDA também pode ter induzido a expressão de uma isoforma e/ou uma menor fosforilação em alguns sítios ativos da SERCA2 no tecido ventricular de P. Molurus. Uma relação direta entre a expressão da SERCA2 com a expressão do PLB foi verificada somente em C. durissus, não havendo tal relação em P. Molurus e C. latirostris. As três espécies de répteis expressaram o PLB com mesma massa molecular, de 50 kDa, e diferente da do rato, que é de 25 kDa. A grande distância evolutiva que separa os répteis dos mamíferos pode ter ocasionado o surgimento de isoformas entre esses grupos, explicando tal diferença. O aumento da expressão do NCX em C. latirostris do grupo alimentar Digestão sugere uma maior mobilização do cálcio e um maior inotropismo de forma frequência-específica através dessa proteína. A maior expressão do NCX juntamente com a menor expressão da SERCA2 e do PLB em C. durissus no grupo alimentar Jejum em relação aos outros dois grupos alimentares sugere uma maior mobilização do cálcio pelo NCX nesse regime de alimentação, o que seria vantajoso do ponto de vista energético. A expressão do NCX com diferentes massas moleculares entre as três espécies estudadas, um menor número de regiões conservadas em animais filogeneticamente mais distantes, e a grande plasticidade do gene da proteína NCX em formar proteínas distintas, sugere a expressão de proteínas isoformas nos répteis estudados.The Sarcoplasmic reticulum calcium ATPase (SERCA), phospholamban (PLB) and the Na+-Ca2+ exchanger (NCX) proteins are essential for the cardiac calcium management and myocardial contractility in vertebrates. The increase in metabolic rate generated from mechanical and physiological process of digestion is known as specific dynamic action (SDA) and represents the energy cost of processing, digestion and absorption of food. In several groups of reptiles, feeding generates a rapid increase in rates of gas exchange, whose peak usually occurs one or two days after feeding, before suffering a slower decline and returning to preprandial values. Ingestion of large quantity of food demands a metabolic elevation and leads to indemnities related in ventricular mass and an increase in myocardial force contraction, avoiding an overload on the cardiovascular system. During the fasting, depletion of body mass occurs and it can also reach the heart muscle. To describe the importance and the changes in SERCA2, PLB and NCX proteins on the effects of feeding/digestion in reptiles broad-snouted caiman (Caiman latirostris), burmese phyton (Python Molurus) and also by prolonged fasting in South-American rattlesnake (Crotalus durissus terrificus) Western blotting technique was used. We observed the homology existence between the proteins of reptiles in relation to mammals. The SDA increased expression of SERCA2 protein in three species of reptiles. The SDA can also have unduced the expression of an isoform and/or reduced phosphorylation at some active sites of SERCA2 in ventricular tissue of P. Molurus. A direct relationship between the expression of SERCA2 with the PLB expression in C. durissus was observed. However in P. Molurus and C. latirostris this relation does not exist. The three reptiles expressed the PLB with molecular mass of 50 kDa, whereas the mouse expressed 25 kDa. The vast evolutionary distance that separates mammals of reptiles may have caused the rise of isoforms between these groups, explaining this difference. The increased expression of NCX along with lower expression of SERCA2 and PLB in C. durissus in food group Fasting compared to the other two groups suggests a higher calcium mobilization in this feeding regime, which would be advantageous from the energy point of view. The expression of NCX with different molecular mass between the three species, a smaller number of consensus regions with the animals phylogenetically more distant and the great plasticity of NCX gene to form distinct proteins, suggest the expression of proteins isoforms with the reptiles studied in this research
Johan L Van Leeuwen - One of the best experts on this subject based on the ideXlab platform.
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a three dimensional kinematic analysis of tongue flicking in Python Molurus
The Journal of Experimental Biology, 2004Co-Authors: Jurriaan H De Groot, Inke Van Der Sluijs, Peter Snelderwaard, Johan L Van LeeuwenAbstract:The forked snake tongue is a muscular organ without hard skeletal support. A functional interpretation of the variable arrangement of the intrinsic muscles along the tongue requires a quantitative analysis of the motion performance during tongue protrusion and flicking. Therefore, high-speed fluoroscopy and high-speed stereo photogrammetry were used to analyse the three-dimensional shape changes of the tongue in Python Molurus bivittatus (Boidae). The posterior protruding part of the tongue elongated up to 130% while the flicking anterior portion elongated maximally 60%. The differences in tongue strains relate to the absence or presence, respectively, of longitudinal muscle fibres in the peripheral tongue. Maximum overall protrusion velocity (4.3 m s(-1)) occurred initially when the tongue tip left the mouth. Maximum tongue length of approximately 0.01 body length (20 mm) was reached during the first tongue flick. These observations are discussed within the scope of the biomechanical constraints of hydrostatic tongue protrusion: a negative forward pressure gradient, longitudinal tongue compliance and axial tongue stiffness. The three-dimensional deformation varied along the tongue with a mean curvature of 0.06 mm(-1) and a maximum value of 0.5 mm(-1). At the basis of the anterior forked portion of the tongue tips, extreme curvatures up to 2.0 mm(-1) were observed. These quantitative results support previously proposed inferences about a hydrostatic elongation mechanism and may serve to evaluate future dynamic models of tongue flicking.
