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1.
PLoS One ; 17(9): e0274085, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36054125

RESUMO

This prospective study aims to establish reference ranges for vertebral heart score (VHS), vertebral left atrial size (VLAS), and radiographic left atrial dimension (RLAD) in pugs. The impact of clinical severity of Brachycephalic Obstructive Airway Syndrome (BOAS), gender, body condition score, and body weight on VHS, VLAS, and RLAD were investigated. Intra- and interobserver correlation was determined. Correlation of radiographic scores to echocardiographic left atrial dimension was inspected. Additionally, for VLAS and RLAD, correlation to VHS was examined. Additionally, an assessment of thoracic and vertebral malformations was performed. Forty-seven privately owned pugs underwent physical examination, echocardiography, and thoracic radiography to determine cardiac health. Thirty-two pugs were eligible for establishing reference ranges for VHS in right lateral radiographs, which was 11.25 ± 0.62 (95% range, 10.1-12.8). Reference ranges for VHS in left lateral, and for VLAS and RLAD in right lateral radiograph were determined in 30 pugs. The VHS in left lateral radiograph was 11.01 ± 0.70 (95% range, 9.4-12.6), VLAS was 1.96 ± 0.38 (95% range, 1.1-2.8), and RLAD was 1.59 ± 0.34 (95% range, 0.7-2.4). Clinical severity of BOAS did not show any impact on radiographic measurements. For VLAS, a significant correlation to VHS was detected by all observers. No other variables had a consistent influence on the radiographic scores given by all observers. Interobserver agreement was almost perfect for VHS (0.89 on right lateral and 0.91 on left lateral image), moderate for VLAS (0.49), and fair for RLAD (0.22). More than one third of the entire study population (18 of 47 pugs) showed at least one thoracic cavity or spine abnormality, often leading to considerable changes in vertebral body shape and size.


Assuntos
Obstrução das Vias Respiratórias , Boidae , Craniossinostoses , Doenças do Cão , Cardiopatias , Animais , Cães , Coração , Átrios do Coração/diagnóstico por imagem , Humanos , Estudos Prospectivos , Radiografia Torácica , Valores de Referência , Síndrome
2.
Vet Clin North Am Exot Anim Pract ; 25(3): 805-821, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36122952

RESUMO

Hematology and biochemistry testing of boas and pythons is a valuable topic for practicing clinicians and researchers alike. This article reviews blood cell morphology (with accompanying images) and reviews the literature for hematologic and biochemical material clinically relevant to the families Boidae and Pythonidae.


Assuntos
Boidae , Patologia Clínica , Animais
3.
Mar Pollut Bull ; 182: 113996, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35921734

RESUMO

The Florida Everglades is a unique and fragile coastal wetland ecosystem that is undergoing a decades-long, large-scale ecological restoration. This freshwater ecosystem in southern Florida has been stressed by diminishment of freshwater flow and water diversion due to agricultural activities and urbanization. The health of this vast ecosystem is also threatened by the presence of a large number of invasive species, including the Burmese python. These large constrictors were introduced to South Florida through the pet trade; first sightings in Everglades National Park occurred in the 1980s. Pythons are naturally camouflaged in the Everglades, which turns out to be an excellent environment for propagation of these huge predators. This top predator has severely disrupted the food web, consuming mammals, birds and even other reptiles. In this paper, the current population control efforts implemented by various management agencies are assessed. While more paid professional hunters should be retained to join the search and removal efforts, innovative control measures are necessary.


Assuntos
Boidae , Animais , Ecossistema , Florida , Espécies Introduzidas , Mamíferos , Áreas Alagadas
4.
J Comp Pathol ; 196: 26-40, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36008042

RESUMO

There is general awareness of artificial selection and its potential implications on the health and welfare of animals. Despite growing popularity and increasing numbers of reptile breeds of atypical colour and pattern variants, only a few studies have investigated the appearance and causes of diseases associated with colour morphs. Ball pythons (Python regius) are among the most frequently bred reptiles and breeders have selected for a multitude of different colour and pattern morphs. Among those colour variants, the spider morph of the ball python is frequently associated with wobble syndrome. The aim of this study was to determine whether a morphological variant can be found and associated with the clinical occurrence of wobble syndrome in spider ball pythons, using computed tomography and magnetic resonance imaging as in-vivo diagnostic methods. Data from five spider and three wild type ball pythons was assessed and evaluated comparatively. We were able to identify distinctive structural differences in inner ear morphology in spider ball pythons, which were highly likely related to wobble syndrome. To our knowledge, this is the first report of these anomalies and provides a basis for further anatomical and genetic studies and discussion of the implications for animal welfare in reptile breeding.


Assuntos
Boidae , Aranhas , Animais , Imageamento por Ressonância Magnética/veterinária , Tomografia Computadorizada por Raios X
5.
PLoS One ; 17(8): e0262788, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35969602

RESUMO

Spider morph ball pythons are a frequently-bred designer morph with striking alterations of the skin color pattern. We created high-resolution µCT-image series through the otic region of the skulls, used 3D-reconstruction software for rendering anatomical models, and compared the anatomy of the semicircular ducts, sacculus and ampullae of wildtype Python regius (ball python) with spider morph snakes. All spider morph snakes showed the wobble condition (i.e., twisting movements of the head, impaired locomotion, difficulty striking or constricting prey items). We describe the inner ear structures in wildtype and spider morph snakes and report a deviant morphology of semicircular canals, ampullae and sacculus in the latter. We also report about associated differences in the desmal skull bones of spider morph snakes, which were characterized by wider semicircular canals, ampullae widened and difficult to discern in µCT, a deformed crus communis, and a small sacculus with a highly deviant X-ray morphology as compared to wildtype individuals. We observed considerable intra- and interindividual variability of these features. This deviant morphology in spider morph snakes could easily be associated with an impairment of sense of equilibrium and the observed neurological wobble condition. Limitations in sample size prevent statistical analyses, but the anatomical evidence is strong enough to support an association between the wobble condition and a malformation of the inner ear structures. A link between artificially selected alterations in pattern and specific color design with neural-crest associated developmental malformations of the statoacoustic organ as known from other vertebrates is discussed.


Assuntos
Boidae , Aranhas , Animais , Boidae/anatomia & histologia , Orelha , Canais Semicirculares , Crânio/anatomia & histologia
6.
Microbiol Spectr ; 10(4): e0158522, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35862992

RESUMO

Mammarenaviruses establish a persistent infection in their rodent and bat hosts, and the evidence suggests that reptarenaviruses and hartmaniviruses found in captive snakes act similarly. In snakes, reptarenaviruses cause boid inclusion body disease (BIBD), which is often associated with secondary infections. Snakes with BIBD usually carry more than a single pair of reptarenavirus S and L segments and occasionally demonstrate hartmanivirus coinfection. Here, we reported the generation of cell lines persistently infected with a single or two reptarenavirus(es) and a cell line with persistent reptarenavirus-hartmanivirus coinfection. By RT-PCR we demonstrated that the amount of viral RNA within the persistently infected cells remains at levels similar to those observed following initial infection. Using antibodies against the glycoproteins (GPs) and nucleoprotein (NP) of reptarenaviruses, we studied the levels of viral protein in cells passaged 10 times after the original inoculation and observed that the expression of GPs declines dramatically during persistent infection, unlike the expression of NP. Immunofluorescence (IF) staining served to demonstrate differences in the distribution of NP within the persistently infected compared to freshly infected cells. IF staining of cells inoculated with the viruses secreted from the persistently infected cell lines produced similar NP staining compared to cells infected with a traditionally passaged virus, suggesting that the altered NP expression pattern of persistently infected cells does not relate to changes in the virus. The cell cultures described herein can serve as tools for studying the coinfection and superinfection interplay between reptarenaviruses and studying the BIBD pathogenesis mechanisms. IMPORTANCE Mammarenaviruses cause a persistent infection in their natural rodent and bat hosts. Reptarenaviruses cause boid inclusion body disease (BIBD) in constrictor snakes, but it is unclear whether snakes are the natural host of these viruses. In this study, we showed that reptarenaviruses established a persistent infection in cultured Boa constrictor cells and that the persistently infected cells continued to produce infectious virus. Our results showed that persistent infection results from subsequent passaging of cells inoculated with a single reptarenavirus, two reptarenaviruses, or even when inoculating the cells with reptarenavirus and hartmanivirus (another arenavirus genus). The results further suggested that coinfection would not result in overt competition between the different reptarenaviruses, thus helping to explain the frequent reptarenavirus coinfections in snakes with BIBD. The established cell culture models of persistent infection could help to elucidate the role of coinfection and superinfection and potential immunosuppression as the pathogenic mechanisms behind BIBD.


Assuntos
Arenaviridae , Boidae , Quirópteros , Coinfecção , Superinfecção , Animais , Arenaviridae/genética , Linhagem Celular
7.
Parasitol Int ; 91: 102617, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35777656

RESUMO

Tongue worms (Subclass: Pentastomida) are endoparasites found in carnivorous reptiles, fish, amphibians, birds, and mammals. Several pentastomids cause pentastomiasis, a zoonotic disease. We encountered tongue worm infection in two reptiles imported into Japan: a Wahlberg's velvet gecko (Homopholis wahlbergii) bred in Germany and a wild-caught green tree python (Morelia viridis) from the Republic of Indonesia. The infecting tongue worms were identified as Raillietiella sp. and Armillifer sp. in the gecko and python, respectively, based on morphological and molecular analyses. Gecko is a newly recorded definitive host harboring Raillietiella tongue worm. Live tongue worms were first detected in domestic reptiles in Japan, and this indicates a risk that these tongue worms could be spread to other animals, as well as humans. Therefore, the diagnosis and treatment of infected pets are of importance. In the case of the two infected reptiles, the availability of fecal egg examination for diagnosis was shown. In addition, the effectiveness of treatment with 200 µg/kg/day ivermectin orally once weekly was demonstrated, without no side-effects and no re-detection of eggs after the cessation of treatment.


Assuntos
Boidae , Lagartos , Pentastomídeos , Anfíbios , Animais , Humanos , Mamíferos , Zoonoses/tratamento farmacológico , Zoonoses/parasitologia
8.
BMC Vet Res ; 18(1): 291, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883142

RESUMO

BACKGROUND: Environmental nontuberculous mycobacteria species that are not members of the M. tuberculosis complex, are ordinary inhabitants of a wide variety of environmental reservoirs and their role in human and animal diseases has been fully recognized. Even if spontaneous mycobacterial infections have been reported in a wide variety of reptiles, this is the first report of systemic fatal mycobacteriosis sustained by Mycobacterium goodii in a pet reptile.  CASE PRESENTATION: An adult, wild caught (WC), male Kenyan sand boa (Eryx colubrinus loveridgei) age unknown, was presented for clinical examination due to decreased activity level, decreased appetite and diarrhea. Blood tests showed unreliable results. Coprologic exam showed a moderate to severe presence of flagellates. X rays and ultrasound showed moderate presence of air and faeces in the large intestine. The snake was hospitalized and oral metronidazole was chosen as antiprotozoal agent in association with subcutaneous warm fluids. The snake was discharged after 2 weeks therapy in good clinical condition. Faecal exam resulted negative. One month after, the snake was quickly hospitalized again because of a recrudescence of symptoms. Biochemistry showed severe increase of AST, ALT and biliary acids. Severe leucocytosis and moderate to severe anemia were highlighted. Ultrasound examination revealed a severe diffused alteration of the liver parenchyma and a fine needle aspiration was performed. The cytological diagnosis was mixed inflammation, with a numerous of unstained rod-shaped bacteria both inside macrophages and free in the sample. The snake's condition rapidly deteriorated and euthanasia was performed. The histology of the coelomic organs confirmed a systemic mycobacteriosis. Real-time PCR identified the mycobacteria as Mycobacterium goodii. CONCLUSIONS: Species from the genus Mycobacterium are among the most important micro-organism including the causative agents of tuberculosis. Even if the general incidence of disease in reptiles due to mycobacteria is comparatively low, they can serve as reservoirs of many ubiquitous mycobacteria species. Mycobacterium goodii is a rapidly growing non-tuberculous mycobacterium that has recently been associated with severe infections in animals and humans. Although in this case the pathogenesis was not completely clear, we highlight the zoonotic risk of mycobacteriosis in exotic animals especially in WC specimens.


Assuntos
Boidae , Infecções por Mycobacterium não Tuberculosas , Mycobacterium , Tuberculose , Animais , Humanos , Quênia , Masculino , Mycobacteriaceae , Infecções por Mycobacterium não Tuberculosas/veterinária , Tuberculose/veterinária
9.
Genes (Basel) ; 13(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35885968

RESUMO

The recent discovery of two independently evolved XX/XY sex determination systems in the snake genera Python and Boa sparked a new drive to study the evolution of sex chromosomes in poorly studied lineages of snakes, where female heterogamety was previously assumed. Therefore, we examined seven species from the genera Eryx, Cylindrophis, Python, and Tropidophis by conventional and molecular cytogenetic methods. Despite the fact that these species have similar karyotypes in terms of chromosome number and morphology, we detected variability in the distribution of heterochromatin, telomeric repeats, and rDNA loci. Heterochromatic blocks were mainly detected in the centromeric regions in all species, although accumulations were detected in pericentromeric and telomeric regions in a few macrochromosomes in several of the studied species. All species show the expected topology of telomeric repeats at the edge of all chromosomes, with the exception of Eryx muelleri, where additional accumulations were detected in the centromeres of three pairs of macrochromosomes. The rDNA loci accumulate in one pair of microchromosomes in all Eryx species and in Cylindrophis ruffus, in one macrochromosome pair in Tropidophis melanurus and in two pairs of microchromosomes in Python regius. Sex-specific differences were not detected, suggesting that these species likely have homomorphic, poorly differentiated sex chromosomes.


Assuntos
Boidae , Animais , Boidae/genética , Análise Citogenética , DNA Ribossômico/genética , Evolução Molecular , Feminino , Masculino , Cromossomos Sexuais
11.
PLoS One ; 17(6): e0266850, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35763487

RESUMO

The present study was carried out to provide insight into the body composition of snakes, which is an important basis for determination of nutrient requirement and physiological processes. Carcasses of 86 captive snakes (31 pythons, 32 colubrids and 23 boas) were available for analysis. Skins and vertebrae bones of 11 snakes and livers of 64 snakes were analysed separately from the carcasses. Crude nutrients, major minerals and trace elements were investigated. The content of crude nutrients of the whole body was similar to those of mammals and birds. Relatively high contents of copper, zinc and especially of iron (up to 23,973 mg/kg dry matter) were found in the body, particularly in the liver. There was an increase of the iron content of the whole body over age.


Assuntos
Boidae , Animais , Composição Corporal , Cobre , Ferro , Mamíferos , Zinco
12.
Circ Res ; 130(12): 1994-2014, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679366

RESUMO

Acute and chronic animal models of exercise are commonly used in research. Acute exercise testing is used, often in combination with genetic, pharmacological, or other manipulations, to study the impact of these manipulations on the cardiovascular response to exercise and to detect impairments or improvements in cardiovascular function that may not be evident at rest. Chronic exercise conditioning models are used to study the cardiac phenotypic response to regular exercise training and as a platform for discovery of novel pathways mediating cardiovascular benefits conferred by exercise conditioning that could be exploited therapeutically. The cardiovascular benefits of exercise are well established, and, frequently, molecular manipulations that mimic the pathway changes induced by exercise recapitulate at least some of its benefits. This review discusses approaches for assessing cardiovascular function during an acute exercise challenge in rodents, as well as practical and conceptual considerations in the use of common rodent exercise conditioning models. The case for studying feeding in the Burmese python as a model for exercise-like physiological adaptation is also explored.


Assuntos
Boidae , Condicionamento Físico Animal , Animais , Boidae/genética , Fenômenos Fisiológicos Cardiovasculares , Modelos Animais , Condicionamento Físico Animal/fisiologia , Roedores
13.
Mol Phylogenet Evol ; 174: 107542, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35690376

RESUMO

The mountains of southern California represent unique, isolated ecosystems that support distinct high-elevation habitats found nowhere else in the area. Analyses of several moisture-dependent species across these sky-islands indicate they exist as locally endemic lineages that occur across these fragmented mountains ranges. The Rubber Boa is a semi-fossorial snake species that is widely distributed in the cooler and more moist ecoregions regions of western North America, including isolated populations across southern California mountain ranges. We developed a genomic and ecological dataset to examine genetic diversity within Rubber Boas and to determine if the endemic Southern Rubber Boa represents a distinct lineage. We quantified current and future habitat suitability under a range of climate change scenarios, and discuss the possible environmental threats facing these unique montane isolates. Our results support four major lineages within Rubber Boas, with genetic breaks that are consistent with biogeographic boundaries observed in other co-distributed, cool-temperature, moisture adapted species. Our data support previous studies that the Southern Rubber Boa is an independent evolutionary unit and now includes multiple locally endemic sky-island populations, restricted to isolated mountain tops and ranges across southern California. Analyses of future habitat suitability indicate that many of these sky-island populations will lose most of their suitable habitat over the next 70 years given predicted increases in drought, rising temperatures, and wildfires. Collectively these data emphasize the critical conservation needs of these montane ecosystems in southern California under current and projected climate change conditions.


Assuntos
Boidae , Animais , California , Ecossistema , Genômica , Filogenia , Borracha
14.
J Exp Biol ; 225(13)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642934

RESUMO

The walls of the mammalian aorta and pulmonary artery are characterized by diverging morphologies and mechanical properties, which have been correlated with high systemic and low pulmonary blood pressure, as a result of intraventricular pressure separation. However, the relationship between intraventricular pressure separation and diverging aortic and pulmonary artery wall morphologies and mechanical characteristics is not understood. The snake cardiovascular system poses a unique model for the study of this relationship, as representatives both with and without intraventricular pressure separation exist. In this study, we performed uniaxial tensile testing on vessel samples taken from the aortas and pulmonary arteries of the Madagascar ground boa, Acrantophis madagascariensis, a species without intraventricular pressure separation. We then compared these morphological and mechanical characteristics with samples from the ball python, Python regius, and the yellow anaconda, Eunectes notaeus - species with and without intraventricular pressure separation, respectively. Our data suggest that although the aortas and pulmonary arteries of A. madagascariensis respond similarly to the same intramural blood pressure, they diverge in morphology, and that this attribute extends to E. notaeus. In contrast, P. regius aortas and pulmonary arteries diverge both morphologically and in terms of their mechanical properties. Our data indicate that intraventricular pressure separation cannot fully explain diverging aortic and pulmonary artery morphologies. Following the law of Laplace, we propose that pulmonary arteries of small luminal diameter represent a mechanism to protect the fragile pulmonary vasculature by reducing the blood volume that passes through, to which genetic factors may contribute more strongly than physiological parameters.


Assuntos
Boidae , Animais , Aorta/fisiologia , Pressão Sanguínea , Boidae/fisiologia , Madagáscar , Mamíferos , Artéria Pulmonar/fisiologia , Pressão Ventricular
15.
Sci Rep ; 12(1): 7864, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550565

RESUMO

Design inspiration comes from the continuous stimulation of external information and the continuous accumulation of knowledge. In order to obtain an ideal design inspiration from nature, researchers have proposed a large number of biological information retrieval and knowledge acquisition methods. But how to purposefully acquire valuable biological knowledge in order to effectively stimulate design inspiration and produce the novel and feasible designs idea is still an urgent problem to be solved. This paper proposes a method for acquiring valuable biological knowledge to efficiently stimulate inspiration and quickly conceive solutions in engineering design. First, keywords, such as the functional requirements and key components of design objects, are selected as the engineering terminologies. Next, biological keywords related to the engineering terminologies are searched from the biological dictionary and biology websites. Then in order to retrieve enough biological knowledge, these biological keywords are expanded manually and automatically respectively based on Thesaurus Webpage and WordNet database, and expanded keywords are filtered according to repeated words and different forms of the same words. Finally, in the biological knowledge base, biological keywords that had been filtered are used to obtain biological knowledge with Python web crawler programming. Through an example of application for ship equipment, the effectiveness of the method is verified.


Assuntos
Boidae , Animais , Cognição , Bases de Dados Factuais , Armazenamento e Recuperação da Informação
16.
Behav Brain Res ; 429: 113910, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513170

RESUMO

Burmese pythons (Python molurus bivitattus) use a unique infrared (IR) targeting system to acquire prey, avoid predators and seek thermoregulatory sites through detection of IR energy in the environment. Previous studies of sensitivity of the python IR system that relied on analysis of complex, natural behaviors lacked robust, reliable responses in animals habituated to experiments, and in vitro electrophysiological study failed to test behavioral function of the implicated protein thermoreceptor, TRPA1. The present study used conditioned discrimination procedures to analyze behavioral sensitivity and signal transduction in the python IR system. Pythons trained to behaviorally discriminate thermal stimuli averaged 70% correct choices, but failed to make correct choices when pit organs were physically occluded with IR-blocking material. The pythons exhibited greater sensitivity to thermal stimuli than previously reported, evident by correct choices that exceeded chance in response to a 14 × 10-6 W cm-2 irradiance contrast, or 0.5 °C thermal differential. Finally, in a test of the behavioral role of the putative thermoreceptor protein TRPA1, despite pit organ treatment with a TRPA1 inhibitor, python performance exceeded chance and was similar to baseline discrimination and control trials. Collectively, the results suggest that the IR system is a high sensitivity, broad-spectrum thermosensor that may operate through different and/or multiple thermoreceptive proteins with overlapping spectral response profiles. The findings reported here provide a better understanding of the relationship between the brain, behavior and environment in driving survival and ecological success of the Burmese python, especially as an invasive megapredator in the southern United States.


Assuntos
Boidae , Animais , Boidae/fisiologia , Transdução de Sinais
18.
Magn Reson Med ; 88(2): 890-900, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35426467

RESUMO

PURPOSE: Hyperpolarized 13 C MRI is a powerful technique to study dynamic metabolic processes in vivo; but it has predominantly been used in mammals, mostly humans, pigs, and rodents. METHODS: In the present study, we use this technique to characterize the metabolic fate of hyperpolarized [1-13 C]pyruvate in Burmese pythons (Python bivittatus), a large species of constricting snake that exhibits a four- to tenfold rise in metabolism and large growth of the visceral organs within 24-48 h of ingestion of their large meals. RESULTS: We demonstrate a fivefold elevation of the whole-body lactate-to-pyruvate ratio in digesting snakes, pointing to a large rise in lactate production from pyruvate. Consistent with the well-known metabolic stimulation of digestion, measurements of mitochondrial respiration in hepatocytes in vitro indicate a marked postprandial upregulation of mitochondrial respiration. We observed that a low SNR of the hyperpolarized 13 C produced metabolites in the python, and this lack of signal was possibly due to the low metabolism of reptiles compared with mammals, preventing quantification of alanine and bicarbonate production with the experimental setup used in this study. Spatial quantification of the [1-13 C]lactate was only possible in postprandial snakes (with high metabolism), where a statistically significant difference between the heart and liver was observed. CONCLUSION: We confirm the large postprandial rise in the wet mass of most visceral organs, except for the heart, and demonstrated that it is possible to image the [1-13 C]pyruvate uptake and intracellular conversion to [1-13 C]lactate in ectothermic animals.


Assuntos
Boidae , Ácido Pirúvico , Animais , Boidae/metabolismo , Isótopos de Carbono/metabolismo , Digestão , Ácido Láctico/metabolismo , Imageamento por Ressonância Magnética/métodos , Mamíferos/metabolismo , Ácido Pirúvico/metabolismo , Suínos
19.
J Exp Biol ; 225(6)2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35325925

RESUMO

The evolution of constriction and of large prey ingestion within snakes are key innovations that may explain the remarkable diversity, distribution and ecological scope of this clade, relative to other elongate vertebrates. However, these behaviors may have simultaneously hindered lung ventilation such that early snakes may have had to circumvent these mechanical constraints before those behaviors could evolve. Here, we demonstrate that Boa constrictor can modulate which specific segments of ribs are used to ventilate the lung in response to physically hindered body wall motions. We show that the modular actuation of specific segments of ribs likely results from active recruitment or quiescence of derived accessory musculature. We hypothesize that constriction and large prey ingestion were unlikely to have evolved without modular lung ventilation because of their interference with lung ventilation, high metabolic demands and reliance on sustained lung convection. This study provides a new perspective on snake evolution and suggests that modular lung ventilation evolved during or prior to constriction and large prey ingestion, facilitating snakes' remarkable radiation relative to other elongate vertebrates.


Assuntos
Boidae , Animais , Boidae/fisiologia , Pulmão , Serpentes
20.
J Gen Physiol ; 154(4)2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35323838

RESUMO

As an opportunistic predator, the Burmese python (Python molurus bivittatus) consumes large and infrequent meals, fasting for up to a year. Upon consuming a large meal, the Burmese python exhibits extreme metabolic responses. To define the pathways that regulate these postprandial metabolic responses, we performed a comprehensive profile of plasma metabolites throughout the digestive process. Following ingestion of a meal equivalent to 25% of its body mass, plasma lipoproteins and metabolites, such as chylomicra and bile acids, reach levels observed only in mammalian models of extreme dyslipidemia. Here, we provide evidence for an adaptive response to postprandial nutrient overload by the python liver, a critical site of metabolic homeostasis. The python liver undergoes a substantial increase in mass through proliferative processes, exhibits hepatic steatosis, hyperlipidemia-induced insulin resistance indicated by PEPCK activation and pAKT deactivation, and de novo fatty acid synthesis via FASN activation. This postprandial state is completely reversible. We posit that Burmese pythons evade the permanent hepatic damage associated with these metabolic states in mammals using evolved protective measures to inactivate these pathways. These include a transient activation of hepatic nuclear receptors induced by fatty acids and bile acids, including PPAR and FXR, respectively. The stress-induced p38 MAPK pathway is also transiently activated during the early stages of digestion. Taken together, these data identify a reversible metabolic response to hyperlipidemia by the python liver, only achieved in mammals by pharmacologic intervention. The factors involved in these processes may be relevant to or leveraged for remediating human hepatic pathology.


Assuntos
Boidae , Adaptação Fisiológica , Animais , Boidae/metabolismo , Humanos , Fígado , Mamíferos , Nutrientes , Período Pós-Prandial/fisiologia
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