Download or read book Carbohydrate Metabolism During Prolonged Fasting in the Northern Elephant Seal written by Cory D. Champagne and published by . This book was released on 2011 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Changes in standard metabolism during long term fasting in northern elephant seal pups Mirounga angustirostris written by L.D. REA and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thyroidal Regulation of Substrate Metabolism in Fasting Northern Elephant Seal Pups written by and published by . This book was released on 2016 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: To a number of physiological and pathological human conditions, there are a variety of natural animal models that can be studied in an effort to obtain greater knowledge and insight into the progression of the disease, as well as enable more accurate and successful therapeutic strategies. The northern elephant seal, specifically the fasting pups, have been established as a powerful, natural model for a number of human diseases, including the onset and development of insulin resistance. Thyroidal regulation has been implicated to change or be changed during the progression of the disease. Therefore, the aim of this dissertation is to elucidate how the two are regulating one another, and specifically what the contributions of an active thyroidal system are, to the regulation of substrate metabolism, especially lipid. In the first chapter, we demonstrated that despite a prolonged fasting period, northern elephant seal pups do not down-regulate thyroid hormone-mediated events, but rather increase all components that would result in increased cellular metabolism. In the second chapter we showed that fasting duration increases the sensitivity of adipose TH-mediated mechanisms to insulin, some of which may be mediated by increased glucose. The third chapter underscored the physiological relevance of an increased thyroidal status, which very clearly is substantially up-regulated with fasting duration, as the thyroid gland evidently increases its production of thyroid hormones with fasting duration. The fourth chapter reveals the contribution of this perplexing physiological response to fasting and its capacity to not only drive lipid metabolism but also lead the system into a necessary state of insulin resistance. Evolution has led some species to develop unique adaptations to environmental influences and lifestyles that are fascinating, perplexing and, if only understood, bare solutions to widespread health issues. Elephant seals are such a species. Despite prolonged fasting their metabolism neither slows down nor reduces its sensitivity to stimulation, as is common, to avoid resource depletion. Instead we find the opposite. Increased thyroid hormone levels and dynamic response to thyroid gland stimulation reveal how the seals thrive on a fasting-driven body fat diet. These studies have the potential to elucidate new therapeutic targets for hormone treatment of human obesity and related metabolic dysfunctions.
Download or read book Glucose Metabolism in Fasting Elephant Seal Pups written by Edward Oliver Keith and published by . This book was released on 1984 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparative Physiology of Fasting Starvation and Food Limitation written by Marshall D. McCue and published by Springer Science & Business Media. This book was released on 2012-05-17 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: All animals face the possibility of food limitation and ultimately starvation-induced mortality. This book summarizes state of the art of starvation biology from the ecological causes of food limitation to the physiological and evolutionary consequences of prolonged fasting. It is written for an audience with an understanding of general principles in animal physiology, yet offers a level of analysis and interpretation that will engage seasoned scientists. Each chapter is written by active researchers in the field of comparative physiology and draws on the primary literature of starvation both in nature and the laboratory. The chapters are organized among broad taxonomic categories, such as protists, arthropods, fishes, reptiles, birds, and flying, aquatic, and terrestrial mammals including humans; particularly well-studied animal models, e.g. endotherms are further organized by experimental approaches, such as analyses of blood metabolites, stable isotopes, thermobiology, and modeling of body composition.
Download or read book Elephant Seals written by Burney J. Le Beouf and published by Univ of California Press. This book was released on 2023-11-10 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: The largest of all seals, elephant seals rank among the most impressive of marine mammals. They are renowned for their spectacular recovery from near-extinction at the end of the nineteenth century when seal hunters nearly eliminated the entire northern species. No other vertebrate has come so close to extinction and made such a complete recovery. The physiological extremes that elephant seals can tolerate are also remarkable: females fast for a month while lactating, and the largest breeding males fast for over one hundred days during the breeding seasons, at which times both sexes lose forty percent of their body weight. Elephant seals dive constantly during their long foraging migrations, spending more time under water than most whales and diving deeper and longer than any other marine mammal. This first book-length discussion of elephant seals brings together worldwide expertise from scientists who describe and debate recent research, including the history and status of various populations, their life-history tactics, and other findings obtained with the help of modern microcomputer diving instruments attached to free-ranging seals. Essential for all marine mammalogists for its information and its methodological innovations, Elephant Seals will also illuminate current debates about species extinctions and possible means of preventing them. This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1994.
Download or read book Prolonged Fasting in Pinnipeds written by Lorrie Darlene Rea and published by . This book was released on 1995 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Encyclopedia of Marine Mammals written by Bernd Würsig and published by Academic Press. This book was released on 2017-11-27 with total page 1190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia of Marine Mammals, Third Edition covers the ecology, behavior, conservation, evolution, form and function of whales, dolphins, seals, sea lions, manatees, dugongs, otters and polar bears. This edition provides new content on anthropogenic concerns, latest information on emerging threats such as ocean noise, and impacts of climate change. With authors and editors who are world experts, this new edition is a critical resource for all who are interested in marine mammals, especially upper level undergraduate and graduate students, researchers, and managers, and is a top reference for those in related fields, from oceanographers to environmental scientists. Significant content and topic updates, as well as the addition of new topics in such areas as anthropogenic disturbance Visual maps of the oceans and seas mentioned in contributions, helping to place the geographical features described in the text with clear, consistent species illustrations Written to help users learn new information or brush up on a topic quickly, with the references at the end of each entry to help guide readers into more specialist literature
Download or read book Physiology of Marine Mammals written by Michael Castellini and published by CRC Press. This book was released on 2023-07-05 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Suppose you were designing a marine mammal. What would they need to live in the ocean? How would you keep them warm? What design features would allow them to dive for very long periods to extreme depths? Do they need water to drink? How would they minimize the cost of swimming, and how would they find their prey in the deep and dark? These questions and more are examined in detail throughout Marine Mammal Physiology, which explores how marine mammals live in the sea from a physiological point of view. This undergraduate textbook considers the essential aspects of what makes a marine mammal different from terrestrial mammals, beyond just their environment. It focuses on the physiological and biochemical traits that have allowed this group of mammals to effectively exploit the marine environment that is so hostile to humans. The content of this book is organised around common student questions, taking the undergraduate's point of view as the starting point. Each chapter provides a set of PowerPoint slides for instructors to use in teaching and students to use as study guides. New "Study Questions" and "Critical Thinking Points" conclude each chapter, which are each motivated by a "Driving Question" such as "How do mammals stay warm in a cold ocean?" or "How do mammals survive the crushing pressures of the deep sea?" Full-colour images and comprehensive, accessible content make this the definitive textbook for marine mammal physiology.
Download or read book The physiological consequences of breath hold diving in marine mammals the Scholander legacy written by Andreas Fahlman and published by Frontiers E-books. This book was released on with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: Breath-hold diving marine mammals are able to remain submerged for prolonged periods of time and dive to phenomenal depths while foraging. A number of physiological, biochemical and behavioral traits have been suggested that enable this life style, including the diving response, lung collapse, increased O2 stores, diving induced hypometabolism, and stroke-and-glide behavior to reduce dive metabolic cost. Since the initial studies by Scholander in the 1940‘s, when most of the physiological and biochemical traits were suggested, few have received as much study as the diving response and O2 management. The calculated aerobic dive limit (cADL) was an important concept which allowed calculation of the aerobic dive duration, and was defined as the total O2 stores divided by the rate of O2 consumption (metabolic rate). The total O2 stores have been defined for several species, and studies in both forced and freely diving animals have refined the metabolic cost of diving. Currently there appears to be little consensus about whether marine mammals perform a significant proportion of dives exceeding the cADL or not and there may be large differences between species. The diving response is a conserved physiological trait believed to arise from natural selection. The response includes diving-induced bradycardia, peripheral vasoconstriction, and altered blood flow distribution. While the response results in reduced cardiac work, it is not clear whether this is required to reduce the overall metabolic rate. An alternate hypothesis is that the primary role of the diving bradycardia is to regulate the degree of hypoxia in skeletal muscle so that blood and muscle O2 stores can be used more efficiently. Scholander suggested that the respiratory anatomy of marine mammals resulted in alveolar collapse at shallow depths (lung collapse), thereby limiting gas exchange. This trait would limit uptake of N2 and thereby reduce the risk of inert gas bubble formation and decompression sickness. In his initial treatise, Scholander suggested that alveolar collapse probably made inert gas bubble formation unlikely during a single dive, but that repeated dives could result in significant accumulation that could be risky. Despite this, lung collapse has been quoted as the main adaptation by which marine mammals reduce N2 levels and inert gas bubble formation. It was surprising, therefore, when recent necropsy reports from mass stranded whales indicated DCS like symptoms. More recent studies have shown that live marine mammals appear to experience bubbles under certain circumstances. These results raise some interesting questions. For example, are marine mammals ever at risk of DCS, and if so could N2 accumulation limit dive performance? While an impressive number of studies have provided a theoretical framework that explains the mechanistic basis of the diving response, and O2 management, many questions remain, some widely-accepted ideas actually lack sufficient experimental confirmation, and a variety of marine mammal species, potentially novel models for elucidating new diving adaptations, are understudied. The aim of this Frontiers Topic is to provide a synthesis of the current knowledge about the physiological responses of marine mammals that underlie their varied dive behavior. We also include novel contributions that challenge current ideas and that probe new hypotheses, utilize new experimental approaches, and explore new model species. We show that the field has recently entered a phase of renewed discovery that is not only unraveling more secrets of the natural diving response but will drive new applications to aid human exploration of the ocean depths. We also welcome comparative analyses, especially contributions that compare marine mammals with human divers.
Download or read book The Regulation of Fuel Homeostasis in Young Northern Elephant Seals written by Vicky Lee Kirby and published by . This book was released on 1992 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Experimental Biology written by and published by . This book was released on 2008-08 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Transformational Power of Fasting written by Stephen Harrod Buhner and published by Simon and Schuster. This book was released on 2012-02-02 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fasting practices to reconnect with the sacred, regain a sense of your life’s purpose, and heal physically and emotionally • Details what to expect during your fast physically, emotionally, and spiritually • Provides step-by-step guidelines on preparing for the fast, how long you should fast, what you can and can’t do during the fast, and how to end your fast • Explains how fasting can help or heal many chronic conditions, such as type II diabetes, hypertension, cardiovascular disease, arthritis, psoriasis, and insomnia For millennia humans have fasted for spiritual, emotional, and physical reasons--as a way to heal their bodies, reconnect to the sacred, regain a sense of life’s purpose, and allow their souls to detoxify. We are evolutionarily designed to fast, and the body knows how to do it very well. Fasting allows the body and all its systems to rest, purify, and heal. During a fast, the body enters the same cleansing and healing cycle it normally enters during sleep. As a fast progresses, the body consumes everything that is not essential to bodily functioning--including bacteria, viruses, fibroid tumors, waste products in the blood, buildup around the joints, and stored fat--and the mind and heart release their toxic buildup as well. As Stephen Harrod Buhner reveals, in order to be truly transformed, you must first empty yourself. Offering step-by-step guidelines to fully prepare yourself for a deep fast, Buhner explores what to expect during and after spiritual, emotional, and physical fasting and detoxification. He details the necessary dietary and mental preparations leading up to your fast, what you can and can’t do during a fast, and how to end your fast. He also explains how to plan the length of your fast and how to choose between a water fast, a juice fast, or a mono-diet fast. Revealing how fasting can help or heal many chronic conditions, such as type II diabetes, childhood seizures, hypertension, cardiovascular disease, arthritis, psoriasis, insomnia, and fibromyalgia, Buhner shows fasting as a way to truly inhabit the body, to experience its sacredness, and to activate its deep capabilities for self-healing.
Download or read book Changes in Protein Metabolism and Water Conservation in Northern Elephant Seal Pups During the Postweaning Fast written by Sean Harrison Adams and published by . This book was released on 1991 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cumulated Index Medicus written by and published by . This book was released on 2000 with total page 1844 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Marine Mammals written by Randall W. Davis and published by Springer Nature. This book was released on 2019-11-14 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive book provides new insights into the morphological, metabolic, thermoregulatory, locomotory, diving, sensory, feeding, and sleep adaptations of Cetacea (whales and dolphins), Pinnipedia (seals, sea lions and walrus), Sirenia (manatees and dugongs) and sea otters for an aquatic life. Each chapter reviews the discoveries from previous studies and integrates recent research using new techniques and technology. Readers will gain an understanding of the remarkable adaptations that enable marine mammals to spend all or most of their lives at sea, often while hunting prey at depth.
Download or read book Integrating Emerging Technologies into Marine Megafauna Conservation Management written by Peter H. Dutton and published by Frontiers Media SA. This book was released on 2020-01-16 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
